src/sqlite3.c
changeset 130 507895068f83
child 491 d32c60ada438
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/sqlite3.c	Thu Mar 26 15:30:21 2015 +0100
     1.3 @@ -0,0 +1,148882 @@
     1.4 +/******************************************************************************
     1.5 +** This file is an amalgamation of many separate C source files from SQLite
     1.6 +** version 3.8.6.  By combining all the individual C code files into this 
     1.7 +** single large file, the entire code can be compiled as a single translation
     1.8 +** unit.  This allows many compilers to do optimizations that would not be
     1.9 +** possible if the files were compiled separately.  Performance improvements
    1.10 +** of 5% or more are commonly seen when SQLite is compiled as a single
    1.11 +** translation unit.
    1.12 +**
    1.13 +** This file is all you need to compile SQLite.  To use SQLite in other
    1.14 +** programs, you need this file and the "sqlite3.h" header file that defines
    1.15 +** the programming interface to the SQLite library.  (If you do not have 
    1.16 +** the "sqlite3.h" header file at hand, you will find a copy embedded within
    1.17 +** the text of this file.  Search for "Begin file sqlite3.h" to find the start
    1.18 +** of the embedded sqlite3.h header file.) Additional code files may be needed
    1.19 +** if you want a wrapper to interface SQLite with your choice of programming
    1.20 +** language. The code for the "sqlite3" command-line shell is also in a
    1.21 +** separate file. This file contains only code for the core SQLite library.
    1.22 +*/
    1.23 +#define SQLITE_CORE 1
    1.24 +#define SQLITE_AMALGAMATION 1
    1.25 +#ifndef SQLITE_PRIVATE
    1.26 +# define SQLITE_PRIVATE static
    1.27 +#endif
    1.28 +#ifndef SQLITE_API
    1.29 +# define SQLITE_API
    1.30 +#endif
    1.31 +/************** Begin file sqliteInt.h ***************************************/
    1.32 +/*
    1.33 +** 2001 September 15
    1.34 +**
    1.35 +** The author disclaims copyright to this source code.  In place of
    1.36 +** a legal notice, here is a blessing:
    1.37 +**
    1.38 +**    May you do good and not evil.
    1.39 +**    May you find forgiveness for yourself and forgive others.
    1.40 +**    May you share freely, never taking more than you give.
    1.41 +**
    1.42 +*************************************************************************
    1.43 +** Internal interface definitions for SQLite.
    1.44 +**
    1.45 +*/
    1.46 +#ifndef _SQLITEINT_H_
    1.47 +#define _SQLITEINT_H_
    1.48 +
    1.49 +/*
    1.50 +** These #defines should enable >2GB file support on POSIX if the
    1.51 +** underlying operating system supports it.  If the OS lacks
    1.52 +** large file support, or if the OS is windows, these should be no-ops.
    1.53 +**
    1.54 +** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
    1.55 +** system #includes.  Hence, this block of code must be the very first
    1.56 +** code in all source files.
    1.57 +**
    1.58 +** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
    1.59 +** on the compiler command line.  This is necessary if you are compiling
    1.60 +** on a recent machine (ex: Red Hat 7.2) but you want your code to work
    1.61 +** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
    1.62 +** without this option, LFS is enable.  But LFS does not exist in the kernel
    1.63 +** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
    1.64 +** portability you should omit LFS.
    1.65 +**
    1.66 +** The previous paragraph was written in 2005.  (This paragraph is written
    1.67 +** on 2008-11-28.) These days, all Linux kernels support large files, so
    1.68 +** you should probably leave LFS enabled.  But some embedded platforms might
    1.69 +** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
    1.70 +**
    1.71 +** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
    1.72 +*/
    1.73 +#ifndef SQLITE_DISABLE_LFS
    1.74 +# define _LARGE_FILE       1
    1.75 +# ifndef _FILE_OFFSET_BITS
    1.76 +#   define _FILE_OFFSET_BITS 64
    1.77 +# endif
    1.78 +# define _LARGEFILE_SOURCE 1
    1.79 +#endif
    1.80 +
    1.81 +/*
    1.82 +** For MinGW, check to see if we can include the header file containing its
    1.83 +** version information, among other things.  Normally, this internal MinGW
    1.84 +** header file would [only] be included automatically by other MinGW header
    1.85 +** files; however, the contained version information is now required by this
    1.86 +** header file to work around binary compatibility issues (see below) and
    1.87 +** this is the only known way to reliably obtain it.  This entire #if block
    1.88 +** would be completely unnecessary if there was any other way of detecting
    1.89 +** MinGW via their preprocessor (e.g. if they customized their GCC to define
    1.90 +** some MinGW-specific macros).  When compiling for MinGW, either the
    1.91 +** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
    1.92 +** defined; otherwise, detection of conditions specific to MinGW will be
    1.93 +** disabled.
    1.94 +*/
    1.95 +#if defined(_HAVE_MINGW_H)
    1.96 +# include "mingw.h"
    1.97 +#elif defined(_HAVE__MINGW_H)
    1.98 +# include "_mingw.h"
    1.99 +#endif
   1.100 +
   1.101 +/*
   1.102 +** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
   1.103 +** define is required to maintain binary compatibility with the MSVC runtime
   1.104 +** library in use (e.g. for Windows XP).
   1.105 +*/
   1.106 +#if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
   1.107 +    defined(_WIN32) && !defined(_WIN64) && \
   1.108 +    defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
   1.109 +    defined(__MSVCRT__)
   1.110 +# define _USE_32BIT_TIME_T
   1.111 +#endif
   1.112 +
   1.113 +/* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
   1.114 +** first in QNX.  Also, the _USE_32BIT_TIME_T macro must appear first for
   1.115 +** MinGW.
   1.116 +*/
   1.117 +/************** Include sqlite3.h in the middle of sqliteInt.h ***************/
   1.118 +/************** Begin file sqlite3.h *****************************************/
   1.119 +/*
   1.120 +** 2001 September 15
   1.121 +**
   1.122 +** The author disclaims copyright to this source code.  In place of
   1.123 +** a legal notice, here is a blessing:
   1.124 +**
   1.125 +**    May you do good and not evil.
   1.126 +**    May you find forgiveness for yourself and forgive others.
   1.127 +**    May you share freely, never taking more than you give.
   1.128 +**
   1.129 +*************************************************************************
   1.130 +** This header file defines the interface that the SQLite library
   1.131 +** presents to client programs.  If a C-function, structure, datatype,
   1.132 +** or constant definition does not appear in this file, then it is
   1.133 +** not a published API of SQLite, is subject to change without
   1.134 +** notice, and should not be referenced by programs that use SQLite.
   1.135 +**
   1.136 +** Some of the definitions that are in this file are marked as
   1.137 +** "experimental".  Experimental interfaces are normally new
   1.138 +** features recently added to SQLite.  We do not anticipate changes
   1.139 +** to experimental interfaces but reserve the right to make minor changes
   1.140 +** if experience from use "in the wild" suggest such changes are prudent.
   1.141 +**
   1.142 +** The official C-language API documentation for SQLite is derived
   1.143 +** from comments in this file.  This file is the authoritative source
   1.144 +** on how SQLite interfaces are suppose to operate.
   1.145 +**
   1.146 +** The name of this file under configuration management is "sqlite.h.in".
   1.147 +** The makefile makes some minor changes to this file (such as inserting
   1.148 +** the version number) and changes its name to "sqlite3.h" as
   1.149 +** part of the build process.
   1.150 +*/
   1.151 +#ifndef _SQLITE3_H_
   1.152 +#define _SQLITE3_H_
   1.153 +#include <stdarg.h>     /* Needed for the definition of va_list */
   1.154 +
   1.155 +/*
   1.156 +** Make sure we can call this stuff from C++.
   1.157 +*/
   1.158 +#if 0
   1.159 +extern "C" {
   1.160 +#endif
   1.161 +
   1.162 +
   1.163 +/*
   1.164 +** Add the ability to override 'extern'
   1.165 +*/
   1.166 +#ifndef SQLITE_EXTERN
   1.167 +# define SQLITE_EXTERN extern
   1.168 +#endif
   1.169 +
   1.170 +#ifndef SQLITE_API
   1.171 +# define SQLITE_API
   1.172 +#endif
   1.173 +
   1.174 +
   1.175 +/*
   1.176 +** These no-op macros are used in front of interfaces to mark those
   1.177 +** interfaces as either deprecated or experimental.  New applications
   1.178 +** should not use deprecated interfaces - they are support for backwards
   1.179 +** compatibility only.  Application writers should be aware that
   1.180 +** experimental interfaces are subject to change in point releases.
   1.181 +**
   1.182 +** These macros used to resolve to various kinds of compiler magic that
   1.183 +** would generate warning messages when they were used.  But that
   1.184 +** compiler magic ended up generating such a flurry of bug reports
   1.185 +** that we have taken it all out and gone back to using simple
   1.186 +** noop macros.
   1.187 +*/
   1.188 +#define SQLITE_DEPRECATED
   1.189 +#define SQLITE_EXPERIMENTAL
   1.190 +
   1.191 +/*
   1.192 +** Ensure these symbols were not defined by some previous header file.
   1.193 +*/
   1.194 +#ifdef SQLITE_VERSION
   1.195 +# undef SQLITE_VERSION
   1.196 +#endif
   1.197 +#ifdef SQLITE_VERSION_NUMBER
   1.198 +# undef SQLITE_VERSION_NUMBER
   1.199 +#endif
   1.200 +
   1.201 +/*
   1.202 +** CAPI3REF: Compile-Time Library Version Numbers
   1.203 +**
   1.204 +** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
   1.205 +** evaluates to a string literal that is the SQLite version in the
   1.206 +** format "X.Y.Z" where X is the major version number (always 3 for
   1.207 +** SQLite3) and Y is the minor version number and Z is the release number.)^
   1.208 +** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
   1.209 +** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
   1.210 +** numbers used in [SQLITE_VERSION].)^
   1.211 +** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
   1.212 +** be larger than the release from which it is derived.  Either Y will
   1.213 +** be held constant and Z will be incremented or else Y will be incremented
   1.214 +** and Z will be reset to zero.
   1.215 +**
   1.216 +** Since version 3.6.18, SQLite source code has been stored in the
   1.217 +** <a href="http://www.fossil-scm.org/">Fossil configuration management
   1.218 +** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
   1.219 +** a string which identifies a particular check-in of SQLite
   1.220 +** within its configuration management system.  ^The SQLITE_SOURCE_ID
   1.221 +** string contains the date and time of the check-in (UTC) and an SHA1
   1.222 +** hash of the entire source tree.
   1.223 +**
   1.224 +** See also: [sqlite3_libversion()],
   1.225 +** [sqlite3_libversion_number()], [sqlite3_sourceid()],
   1.226 +** [sqlite_version()] and [sqlite_source_id()].
   1.227 +*/
   1.228 +#define SQLITE_VERSION        "3.8.6"
   1.229 +#define SQLITE_VERSION_NUMBER 3008006
   1.230 +#define SQLITE_SOURCE_ID      "2014-08-15 11:46:33 9491ba7d738528f168657adb43a198238abde19e"
   1.231 +
   1.232 +/*
   1.233 +** CAPI3REF: Run-Time Library Version Numbers
   1.234 +** KEYWORDS: sqlite3_version, sqlite3_sourceid
   1.235 +**
   1.236 +** These interfaces provide the same information as the [SQLITE_VERSION],
   1.237 +** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
   1.238 +** but are associated with the library instead of the header file.  ^(Cautious
   1.239 +** programmers might include assert() statements in their application to
   1.240 +** verify that values returned by these interfaces match the macros in
   1.241 +** the header, and thus insure that the application is
   1.242 +** compiled with matching library and header files.
   1.243 +**
   1.244 +** <blockquote><pre>
   1.245 +** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
   1.246 +** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
   1.247 +** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
   1.248 +** </pre></blockquote>)^
   1.249 +**
   1.250 +** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
   1.251 +** macro.  ^The sqlite3_libversion() function returns a pointer to the
   1.252 +** to the sqlite3_version[] string constant.  The sqlite3_libversion()
   1.253 +** function is provided for use in DLLs since DLL users usually do not have
   1.254 +** direct access to string constants within the DLL.  ^The
   1.255 +** sqlite3_libversion_number() function returns an integer equal to
   1.256 +** [SQLITE_VERSION_NUMBER].  ^The sqlite3_sourceid() function returns 
   1.257 +** a pointer to a string constant whose value is the same as the 
   1.258 +** [SQLITE_SOURCE_ID] C preprocessor macro.
   1.259 +**
   1.260 +** See also: [sqlite_version()] and [sqlite_source_id()].
   1.261 +*/
   1.262 +SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
   1.263 +SQLITE_API const char *sqlite3_libversion(void);
   1.264 +SQLITE_API const char *sqlite3_sourceid(void);
   1.265 +SQLITE_API int sqlite3_libversion_number(void);
   1.266 +
   1.267 +/*
   1.268 +** CAPI3REF: Run-Time Library Compilation Options Diagnostics
   1.269 +**
   1.270 +** ^The sqlite3_compileoption_used() function returns 0 or 1 
   1.271 +** indicating whether the specified option was defined at 
   1.272 +** compile time.  ^The SQLITE_ prefix may be omitted from the 
   1.273 +** option name passed to sqlite3_compileoption_used().  
   1.274 +**
   1.275 +** ^The sqlite3_compileoption_get() function allows iterating
   1.276 +** over the list of options that were defined at compile time by
   1.277 +** returning the N-th compile time option string.  ^If N is out of range,
   1.278 +** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_ 
   1.279 +** prefix is omitted from any strings returned by 
   1.280 +** sqlite3_compileoption_get().
   1.281 +**
   1.282 +** ^Support for the diagnostic functions sqlite3_compileoption_used()
   1.283 +** and sqlite3_compileoption_get() may be omitted by specifying the 
   1.284 +** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
   1.285 +**
   1.286 +** See also: SQL functions [sqlite_compileoption_used()] and
   1.287 +** [sqlite_compileoption_get()] and the [compile_options pragma].
   1.288 +*/
   1.289 +#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
   1.290 +SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
   1.291 +SQLITE_API const char *sqlite3_compileoption_get(int N);
   1.292 +#endif
   1.293 +
   1.294 +/*
   1.295 +** CAPI3REF: Test To See If The Library Is Threadsafe
   1.296 +**
   1.297 +** ^The sqlite3_threadsafe() function returns zero if and only if
   1.298 +** SQLite was compiled with mutexing code omitted due to the
   1.299 +** [SQLITE_THREADSAFE] compile-time option being set to 0.
   1.300 +**
   1.301 +** SQLite can be compiled with or without mutexes.  When
   1.302 +** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
   1.303 +** are enabled and SQLite is threadsafe.  When the
   1.304 +** [SQLITE_THREADSAFE] macro is 0, 
   1.305 +** the mutexes are omitted.  Without the mutexes, it is not safe
   1.306 +** to use SQLite concurrently from more than one thread.
   1.307 +**
   1.308 +** Enabling mutexes incurs a measurable performance penalty.
   1.309 +** So if speed is of utmost importance, it makes sense to disable
   1.310 +** the mutexes.  But for maximum safety, mutexes should be enabled.
   1.311 +** ^The default behavior is for mutexes to be enabled.
   1.312 +**
   1.313 +** This interface can be used by an application to make sure that the
   1.314 +** version of SQLite that it is linking against was compiled with
   1.315 +** the desired setting of the [SQLITE_THREADSAFE] macro.
   1.316 +**
   1.317 +** This interface only reports on the compile-time mutex setting
   1.318 +** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
   1.319 +** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
   1.320 +** can be fully or partially disabled using a call to [sqlite3_config()]
   1.321 +** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
   1.322 +** or [SQLITE_CONFIG_MUTEX].  ^(The return value of the
   1.323 +** sqlite3_threadsafe() function shows only the compile-time setting of
   1.324 +** thread safety, not any run-time changes to that setting made by
   1.325 +** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
   1.326 +** is unchanged by calls to sqlite3_config().)^
   1.327 +**
   1.328 +** See the [threading mode] documentation for additional information.
   1.329 +*/
   1.330 +SQLITE_API int sqlite3_threadsafe(void);
   1.331 +
   1.332 +/*
   1.333 +** CAPI3REF: Database Connection Handle
   1.334 +** KEYWORDS: {database connection} {database connections}
   1.335 +**
   1.336 +** Each open SQLite database is represented by a pointer to an instance of
   1.337 +** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
   1.338 +** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
   1.339 +** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
   1.340 +** and [sqlite3_close_v2()] are its destructors.  There are many other
   1.341 +** interfaces (such as
   1.342 +** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
   1.343 +** [sqlite3_busy_timeout()] to name but three) that are methods on an
   1.344 +** sqlite3 object.
   1.345 +*/
   1.346 +typedef struct sqlite3 sqlite3;
   1.347 +
   1.348 +/*
   1.349 +** CAPI3REF: 64-Bit Integer Types
   1.350 +** KEYWORDS: sqlite_int64 sqlite_uint64
   1.351 +**
   1.352 +** Because there is no cross-platform way to specify 64-bit integer types
   1.353 +** SQLite includes typedefs for 64-bit signed and unsigned integers.
   1.354 +**
   1.355 +** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
   1.356 +** The sqlite_int64 and sqlite_uint64 types are supported for backwards
   1.357 +** compatibility only.
   1.358 +**
   1.359 +** ^The sqlite3_int64 and sqlite_int64 types can store integer values
   1.360 +** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
   1.361 +** sqlite3_uint64 and sqlite_uint64 types can store integer values 
   1.362 +** between 0 and +18446744073709551615 inclusive.
   1.363 +*/
   1.364 +#ifdef SQLITE_INT64_TYPE
   1.365 +  typedef SQLITE_INT64_TYPE sqlite_int64;
   1.366 +  typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
   1.367 +#elif defined(_MSC_VER) || defined(__BORLANDC__)
   1.368 +  typedef __int64 sqlite_int64;
   1.369 +  typedef unsigned __int64 sqlite_uint64;
   1.370 +#else
   1.371 +  typedef long long int sqlite_int64;
   1.372 +  typedef unsigned long long int sqlite_uint64;
   1.373 +#endif
   1.374 +typedef sqlite_int64 sqlite3_int64;
   1.375 +typedef sqlite_uint64 sqlite3_uint64;
   1.376 +
   1.377 +/*
   1.378 +** If compiling for a processor that lacks floating point support,
   1.379 +** substitute integer for floating-point.
   1.380 +*/
   1.381 +#ifdef SQLITE_OMIT_FLOATING_POINT
   1.382 +# define double sqlite3_int64
   1.383 +#endif
   1.384 +
   1.385 +/*
   1.386 +** CAPI3REF: Closing A Database Connection
   1.387 +**
   1.388 +** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
   1.389 +** for the [sqlite3] object.
   1.390 +** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
   1.391 +** the [sqlite3] object is successfully destroyed and all associated
   1.392 +** resources are deallocated.
   1.393 +**
   1.394 +** ^If the database connection is associated with unfinalized prepared
   1.395 +** statements or unfinished sqlite3_backup objects then sqlite3_close()
   1.396 +** will leave the database connection open and return [SQLITE_BUSY].
   1.397 +** ^If sqlite3_close_v2() is called with unfinalized prepared statements
   1.398 +** and/or unfinished sqlite3_backups, then the database connection becomes
   1.399 +** an unusable "zombie" which will automatically be deallocated when the
   1.400 +** last prepared statement is finalized or the last sqlite3_backup is
   1.401 +** finished.  The sqlite3_close_v2() interface is intended for use with
   1.402 +** host languages that are garbage collected, and where the order in which
   1.403 +** destructors are called is arbitrary.
   1.404 +**
   1.405 +** Applications should [sqlite3_finalize | finalize] all [prepared statements],
   1.406 +** [sqlite3_blob_close | close] all [BLOB handles], and 
   1.407 +** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
   1.408 +** with the [sqlite3] object prior to attempting to close the object.  ^If
   1.409 +** sqlite3_close_v2() is called on a [database connection] that still has
   1.410 +** outstanding [prepared statements], [BLOB handles], and/or
   1.411 +** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
   1.412 +** of resources is deferred until all [prepared statements], [BLOB handles],
   1.413 +** and [sqlite3_backup] objects are also destroyed.
   1.414 +**
   1.415 +** ^If an [sqlite3] object is destroyed while a transaction is open,
   1.416 +** the transaction is automatically rolled back.
   1.417 +**
   1.418 +** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
   1.419 +** must be either a NULL
   1.420 +** pointer or an [sqlite3] object pointer obtained
   1.421 +** from [sqlite3_open()], [sqlite3_open16()], or
   1.422 +** [sqlite3_open_v2()], and not previously closed.
   1.423 +** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
   1.424 +** argument is a harmless no-op.
   1.425 +*/
   1.426 +SQLITE_API int sqlite3_close(sqlite3*);
   1.427 +SQLITE_API int sqlite3_close_v2(sqlite3*);
   1.428 +
   1.429 +/*
   1.430 +** The type for a callback function.
   1.431 +** This is legacy and deprecated.  It is included for historical
   1.432 +** compatibility and is not documented.
   1.433 +*/
   1.434 +typedef int (*sqlite3_callback)(void*,int,char**, char**);
   1.435 +
   1.436 +/*
   1.437 +** CAPI3REF: One-Step Query Execution Interface
   1.438 +**
   1.439 +** The sqlite3_exec() interface is a convenience wrapper around
   1.440 +** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
   1.441 +** that allows an application to run multiple statements of SQL
   1.442 +** without having to use a lot of C code. 
   1.443 +**
   1.444 +** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
   1.445 +** semicolon-separate SQL statements passed into its 2nd argument,
   1.446 +** in the context of the [database connection] passed in as its 1st
   1.447 +** argument.  ^If the callback function of the 3rd argument to
   1.448 +** sqlite3_exec() is not NULL, then it is invoked for each result row
   1.449 +** coming out of the evaluated SQL statements.  ^The 4th argument to
   1.450 +** sqlite3_exec() is relayed through to the 1st argument of each
   1.451 +** callback invocation.  ^If the callback pointer to sqlite3_exec()
   1.452 +** is NULL, then no callback is ever invoked and result rows are
   1.453 +** ignored.
   1.454 +**
   1.455 +** ^If an error occurs while evaluating the SQL statements passed into
   1.456 +** sqlite3_exec(), then execution of the current statement stops and
   1.457 +** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
   1.458 +** is not NULL then any error message is written into memory obtained
   1.459 +** from [sqlite3_malloc()] and passed back through the 5th parameter.
   1.460 +** To avoid memory leaks, the application should invoke [sqlite3_free()]
   1.461 +** on error message strings returned through the 5th parameter of
   1.462 +** of sqlite3_exec() after the error message string is no longer needed.
   1.463 +** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
   1.464 +** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
   1.465 +** NULL before returning.
   1.466 +**
   1.467 +** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
   1.468 +** routine returns SQLITE_ABORT without invoking the callback again and
   1.469 +** without running any subsequent SQL statements.
   1.470 +**
   1.471 +** ^The 2nd argument to the sqlite3_exec() callback function is the
   1.472 +** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
   1.473 +** callback is an array of pointers to strings obtained as if from
   1.474 +** [sqlite3_column_text()], one for each column.  ^If an element of a
   1.475 +** result row is NULL then the corresponding string pointer for the
   1.476 +** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
   1.477 +** sqlite3_exec() callback is an array of pointers to strings where each
   1.478 +** entry represents the name of corresponding result column as obtained
   1.479 +** from [sqlite3_column_name()].
   1.480 +**
   1.481 +** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
   1.482 +** to an empty string, or a pointer that contains only whitespace and/or 
   1.483 +** SQL comments, then no SQL statements are evaluated and the database
   1.484 +** is not changed.
   1.485 +**
   1.486 +** Restrictions:
   1.487 +**
   1.488 +** <ul>
   1.489 +** <li> The application must insure that the 1st parameter to sqlite3_exec()
   1.490 +**      is a valid and open [database connection].
   1.491 +** <li> The application must not close the [database connection] specified by
   1.492 +**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
   1.493 +** <li> The application must not modify the SQL statement text passed into
   1.494 +**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
   1.495 +** </ul>
   1.496 +*/
   1.497 +SQLITE_API int sqlite3_exec(
   1.498 +  sqlite3*,                                  /* An open database */
   1.499 +  const char *sql,                           /* SQL to be evaluated */
   1.500 +  int (*callback)(void*,int,char**,char**),  /* Callback function */
   1.501 +  void *,                                    /* 1st argument to callback */
   1.502 +  char **errmsg                              /* Error msg written here */
   1.503 +);
   1.504 +
   1.505 +/*
   1.506 +** CAPI3REF: Result Codes
   1.507 +** KEYWORDS: {result code definitions}
   1.508 +**
   1.509 +** Many SQLite functions return an integer result code from the set shown
   1.510 +** here in order to indicate success or failure.
   1.511 +**
   1.512 +** New error codes may be added in future versions of SQLite.
   1.513 +**
   1.514 +** See also: [extended result code definitions]
   1.515 +*/
   1.516 +#define SQLITE_OK           0   /* Successful result */
   1.517 +/* beginning-of-error-codes */
   1.518 +#define SQLITE_ERROR        1   /* SQL error or missing database */
   1.519 +#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
   1.520 +#define SQLITE_PERM         3   /* Access permission denied */
   1.521 +#define SQLITE_ABORT        4   /* Callback routine requested an abort */
   1.522 +#define SQLITE_BUSY         5   /* The database file is locked */
   1.523 +#define SQLITE_LOCKED       6   /* A table in the database is locked */
   1.524 +#define SQLITE_NOMEM        7   /* A malloc() failed */
   1.525 +#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
   1.526 +#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
   1.527 +#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
   1.528 +#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
   1.529 +#define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
   1.530 +#define SQLITE_FULL        13   /* Insertion failed because database is full */
   1.531 +#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
   1.532 +#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
   1.533 +#define SQLITE_EMPTY       16   /* Database is empty */
   1.534 +#define SQLITE_SCHEMA      17   /* The database schema changed */
   1.535 +#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
   1.536 +#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
   1.537 +#define SQLITE_MISMATCH    20   /* Data type mismatch */
   1.538 +#define SQLITE_MISUSE      21   /* Library used incorrectly */
   1.539 +#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
   1.540 +#define SQLITE_AUTH        23   /* Authorization denied */
   1.541 +#define SQLITE_FORMAT      24   /* Auxiliary database format error */
   1.542 +#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
   1.543 +#define SQLITE_NOTADB      26   /* File opened that is not a database file */
   1.544 +#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
   1.545 +#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
   1.546 +#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
   1.547 +#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
   1.548 +/* end-of-error-codes */
   1.549 +
   1.550 +/*
   1.551 +** CAPI3REF: Extended Result Codes
   1.552 +** KEYWORDS: {extended result code definitions}
   1.553 +**
   1.554 +** In its default configuration, SQLite API routines return one of 30 integer
   1.555 +** [result codes].  However, experience has shown that many of
   1.556 +** these result codes are too coarse-grained.  They do not provide as
   1.557 +** much information about problems as programmers might like.  In an effort to
   1.558 +** address this, newer versions of SQLite (version 3.3.8 and later) include
   1.559 +** support for additional result codes that provide more detailed information
   1.560 +** about errors. These [extended result codes] are enabled or disabled
   1.561 +** on a per database connection basis using the
   1.562 +** [sqlite3_extended_result_codes()] API.  Or, the extended code for
   1.563 +** the most recent error can be obtained using
   1.564 +** [sqlite3_extended_errcode()].
   1.565 +*/
   1.566 +#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
   1.567 +#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
   1.568 +#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
   1.569 +#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
   1.570 +#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
   1.571 +#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
   1.572 +#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
   1.573 +#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
   1.574 +#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
   1.575 +#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
   1.576 +#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
   1.577 +#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
   1.578 +#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
   1.579 +#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
   1.580 +#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
   1.581 +#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
   1.582 +#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
   1.583 +#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
   1.584 +#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
   1.585 +#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
   1.586 +#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
   1.587 +#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
   1.588 +#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
   1.589 +#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
   1.590 +#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
   1.591 +#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
   1.592 +#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
   1.593 +#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
   1.594 +#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
   1.595 +#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
   1.596 +#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
   1.597 +#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
   1.598 +#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
   1.599 +#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
   1.600 +#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
   1.601 +#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
   1.602 +#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
   1.603 +#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
   1.604 +#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
   1.605 +#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
   1.606 +#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
   1.607 +#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
   1.608 +#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
   1.609 +#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
   1.610 +#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
   1.611 +#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
   1.612 +#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
   1.613 +#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
   1.614 +#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
   1.615 +#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
   1.616 +#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
   1.617 +#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
   1.618 +
   1.619 +/*
   1.620 +** CAPI3REF: Flags For File Open Operations
   1.621 +**
   1.622 +** These bit values are intended for use in the
   1.623 +** 3rd parameter to the [sqlite3_open_v2()] interface and
   1.624 +** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
   1.625 +*/
   1.626 +#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
   1.627 +#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
   1.628 +#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
   1.629 +#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
   1.630 +#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
   1.631 +#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
   1.632 +#define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
   1.633 +#define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
   1.634 +#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
   1.635 +#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
   1.636 +#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
   1.637 +#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
   1.638 +#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
   1.639 +#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
   1.640 +#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
   1.641 +#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
   1.642 +#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
   1.643 +#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
   1.644 +#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
   1.645 +#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
   1.646 +
   1.647 +/* Reserved:                         0x00F00000 */
   1.648 +
   1.649 +/*
   1.650 +** CAPI3REF: Device Characteristics
   1.651 +**
   1.652 +** The xDeviceCharacteristics method of the [sqlite3_io_methods]
   1.653 +** object returns an integer which is a vector of these
   1.654 +** bit values expressing I/O characteristics of the mass storage
   1.655 +** device that holds the file that the [sqlite3_io_methods]
   1.656 +** refers to.
   1.657 +**
   1.658 +** The SQLITE_IOCAP_ATOMIC property means that all writes of
   1.659 +** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
   1.660 +** mean that writes of blocks that are nnn bytes in size and
   1.661 +** are aligned to an address which is an integer multiple of
   1.662 +** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
   1.663 +** that when data is appended to a file, the data is appended
   1.664 +** first then the size of the file is extended, never the other
   1.665 +** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
   1.666 +** information is written to disk in the same order as calls
   1.667 +** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
   1.668 +** after reboot following a crash or power loss, the only bytes in a
   1.669 +** file that were written at the application level might have changed
   1.670 +** and that adjacent bytes, even bytes within the same sector are
   1.671 +** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
   1.672 +** flag indicate that a file cannot be deleted when open.  The
   1.673 +** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
   1.674 +** read-only media and cannot be changed even by processes with
   1.675 +** elevated privileges.
   1.676 +*/
   1.677 +#define SQLITE_IOCAP_ATOMIC                 0x00000001
   1.678 +#define SQLITE_IOCAP_ATOMIC512              0x00000002
   1.679 +#define SQLITE_IOCAP_ATOMIC1K               0x00000004
   1.680 +#define SQLITE_IOCAP_ATOMIC2K               0x00000008
   1.681 +#define SQLITE_IOCAP_ATOMIC4K               0x00000010
   1.682 +#define SQLITE_IOCAP_ATOMIC8K               0x00000020
   1.683 +#define SQLITE_IOCAP_ATOMIC16K              0x00000040
   1.684 +#define SQLITE_IOCAP_ATOMIC32K              0x00000080
   1.685 +#define SQLITE_IOCAP_ATOMIC64K              0x00000100
   1.686 +#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
   1.687 +#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
   1.688 +#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
   1.689 +#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
   1.690 +#define SQLITE_IOCAP_IMMUTABLE              0x00002000
   1.691 +
   1.692 +/*
   1.693 +** CAPI3REF: File Locking Levels
   1.694 +**
   1.695 +** SQLite uses one of these integer values as the second
   1.696 +** argument to calls it makes to the xLock() and xUnlock() methods
   1.697 +** of an [sqlite3_io_methods] object.
   1.698 +*/
   1.699 +#define SQLITE_LOCK_NONE          0
   1.700 +#define SQLITE_LOCK_SHARED        1
   1.701 +#define SQLITE_LOCK_RESERVED      2
   1.702 +#define SQLITE_LOCK_PENDING       3
   1.703 +#define SQLITE_LOCK_EXCLUSIVE     4
   1.704 +
   1.705 +/*
   1.706 +** CAPI3REF: Synchronization Type Flags
   1.707 +**
   1.708 +** When SQLite invokes the xSync() method of an
   1.709 +** [sqlite3_io_methods] object it uses a combination of
   1.710 +** these integer values as the second argument.
   1.711 +**
   1.712 +** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
   1.713 +** sync operation only needs to flush data to mass storage.  Inode
   1.714 +** information need not be flushed. If the lower four bits of the flag
   1.715 +** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
   1.716 +** If the lower four bits equal SQLITE_SYNC_FULL, that means
   1.717 +** to use Mac OS X style fullsync instead of fsync().
   1.718 +**
   1.719 +** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
   1.720 +** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
   1.721 +** settings.  The [synchronous pragma] determines when calls to the
   1.722 +** xSync VFS method occur and applies uniformly across all platforms.
   1.723 +** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
   1.724 +** energetic or rigorous or forceful the sync operations are and
   1.725 +** only make a difference on Mac OSX for the default SQLite code.
   1.726 +** (Third-party VFS implementations might also make the distinction
   1.727 +** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
   1.728 +** operating systems natively supported by SQLite, only Mac OSX
   1.729 +** cares about the difference.)
   1.730 +*/
   1.731 +#define SQLITE_SYNC_NORMAL        0x00002
   1.732 +#define SQLITE_SYNC_FULL          0x00003
   1.733 +#define SQLITE_SYNC_DATAONLY      0x00010
   1.734 +
   1.735 +/*
   1.736 +** CAPI3REF: OS Interface Open File Handle
   1.737 +**
   1.738 +** An [sqlite3_file] object represents an open file in the 
   1.739 +** [sqlite3_vfs | OS interface layer].  Individual OS interface
   1.740 +** implementations will
   1.741 +** want to subclass this object by appending additional fields
   1.742 +** for their own use.  The pMethods entry is a pointer to an
   1.743 +** [sqlite3_io_methods] object that defines methods for performing
   1.744 +** I/O operations on the open file.
   1.745 +*/
   1.746 +typedef struct sqlite3_file sqlite3_file;
   1.747 +struct sqlite3_file {
   1.748 +  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
   1.749 +};
   1.750 +
   1.751 +/*
   1.752 +** CAPI3REF: OS Interface File Virtual Methods Object
   1.753 +**
   1.754 +** Every file opened by the [sqlite3_vfs.xOpen] method populates an
   1.755 +** [sqlite3_file] object (or, more commonly, a subclass of the
   1.756 +** [sqlite3_file] object) with a pointer to an instance of this object.
   1.757 +** This object defines the methods used to perform various operations
   1.758 +** against the open file represented by the [sqlite3_file] object.
   1.759 +**
   1.760 +** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 
   1.761 +** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
   1.762 +** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
   1.763 +** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
   1.764 +** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
   1.765 +** to NULL.
   1.766 +**
   1.767 +** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
   1.768 +** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
   1.769 +** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
   1.770 +** flag may be ORed in to indicate that only the data of the file
   1.771 +** and not its inode needs to be synced.
   1.772 +**
   1.773 +** The integer values to xLock() and xUnlock() are one of
   1.774 +** <ul>
   1.775 +** <li> [SQLITE_LOCK_NONE],
   1.776 +** <li> [SQLITE_LOCK_SHARED],
   1.777 +** <li> [SQLITE_LOCK_RESERVED],
   1.778 +** <li> [SQLITE_LOCK_PENDING], or
   1.779 +** <li> [SQLITE_LOCK_EXCLUSIVE].
   1.780 +** </ul>
   1.781 +** xLock() increases the lock. xUnlock() decreases the lock.
   1.782 +** The xCheckReservedLock() method checks whether any database connection,
   1.783 +** either in this process or in some other process, is holding a RESERVED,
   1.784 +** PENDING, or EXCLUSIVE lock on the file.  It returns true
   1.785 +** if such a lock exists and false otherwise.
   1.786 +**
   1.787 +** The xFileControl() method is a generic interface that allows custom
   1.788 +** VFS implementations to directly control an open file using the
   1.789 +** [sqlite3_file_control()] interface.  The second "op" argument is an
   1.790 +** integer opcode.  The third argument is a generic pointer intended to
   1.791 +** point to a structure that may contain arguments or space in which to
   1.792 +** write return values.  Potential uses for xFileControl() might be
   1.793 +** functions to enable blocking locks with timeouts, to change the
   1.794 +** locking strategy (for example to use dot-file locks), to inquire
   1.795 +** about the status of a lock, or to break stale locks.  The SQLite
   1.796 +** core reserves all opcodes less than 100 for its own use.
   1.797 +** A [file control opcodes | list of opcodes] less than 100 is available.
   1.798 +** Applications that define a custom xFileControl method should use opcodes
   1.799 +** greater than 100 to avoid conflicts.  VFS implementations should
   1.800 +** return [SQLITE_NOTFOUND] for file control opcodes that they do not
   1.801 +** recognize.
   1.802 +**
   1.803 +** The xSectorSize() method returns the sector size of the
   1.804 +** device that underlies the file.  The sector size is the
   1.805 +** minimum write that can be performed without disturbing
   1.806 +** other bytes in the file.  The xDeviceCharacteristics()
   1.807 +** method returns a bit vector describing behaviors of the
   1.808 +** underlying device:
   1.809 +**
   1.810 +** <ul>
   1.811 +** <li> [SQLITE_IOCAP_ATOMIC]
   1.812 +** <li> [SQLITE_IOCAP_ATOMIC512]
   1.813 +** <li> [SQLITE_IOCAP_ATOMIC1K]
   1.814 +** <li> [SQLITE_IOCAP_ATOMIC2K]
   1.815 +** <li> [SQLITE_IOCAP_ATOMIC4K]
   1.816 +** <li> [SQLITE_IOCAP_ATOMIC8K]
   1.817 +** <li> [SQLITE_IOCAP_ATOMIC16K]
   1.818 +** <li> [SQLITE_IOCAP_ATOMIC32K]
   1.819 +** <li> [SQLITE_IOCAP_ATOMIC64K]
   1.820 +** <li> [SQLITE_IOCAP_SAFE_APPEND]
   1.821 +** <li> [SQLITE_IOCAP_SEQUENTIAL]
   1.822 +** </ul>
   1.823 +**
   1.824 +** The SQLITE_IOCAP_ATOMIC property means that all writes of
   1.825 +** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
   1.826 +** mean that writes of blocks that are nnn bytes in size and
   1.827 +** are aligned to an address which is an integer multiple of
   1.828 +** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
   1.829 +** that when data is appended to a file, the data is appended
   1.830 +** first then the size of the file is extended, never the other
   1.831 +** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
   1.832 +** information is written to disk in the same order as calls
   1.833 +** to xWrite().
   1.834 +**
   1.835 +** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
   1.836 +** in the unread portions of the buffer with zeros.  A VFS that
   1.837 +** fails to zero-fill short reads might seem to work.  However,
   1.838 +** failure to zero-fill short reads will eventually lead to
   1.839 +** database corruption.
   1.840 +*/
   1.841 +typedef struct sqlite3_io_methods sqlite3_io_methods;
   1.842 +struct sqlite3_io_methods {
   1.843 +  int iVersion;
   1.844 +  int (*xClose)(sqlite3_file*);
   1.845 +  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
   1.846 +  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
   1.847 +  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
   1.848 +  int (*xSync)(sqlite3_file*, int flags);
   1.849 +  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
   1.850 +  int (*xLock)(sqlite3_file*, int);
   1.851 +  int (*xUnlock)(sqlite3_file*, int);
   1.852 +  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
   1.853 +  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
   1.854 +  int (*xSectorSize)(sqlite3_file*);
   1.855 +  int (*xDeviceCharacteristics)(sqlite3_file*);
   1.856 +  /* Methods above are valid for version 1 */
   1.857 +  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
   1.858 +  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
   1.859 +  void (*xShmBarrier)(sqlite3_file*);
   1.860 +  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
   1.861 +  /* Methods above are valid for version 2 */
   1.862 +  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
   1.863 +  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
   1.864 +  /* Methods above are valid for version 3 */
   1.865 +  /* Additional methods may be added in future releases */
   1.866 +};
   1.867 +
   1.868 +/*
   1.869 +** CAPI3REF: Standard File Control Opcodes
   1.870 +** KEYWORDS: {file control opcodes} {file control opcode}
   1.871 +**
   1.872 +** These integer constants are opcodes for the xFileControl method
   1.873 +** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
   1.874 +** interface.
   1.875 +**
   1.876 +** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
   1.877 +** opcode causes the xFileControl method to write the current state of
   1.878 +** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
   1.879 +** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
   1.880 +** into an integer that the pArg argument points to. This capability
   1.881 +** is used during testing and only needs to be supported when SQLITE_TEST
   1.882 +** is defined.
   1.883 +** <ul>
   1.884 +** <li>[[SQLITE_FCNTL_SIZE_HINT]]
   1.885 +** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
   1.886 +** layer a hint of how large the database file will grow to be during the
   1.887 +** current transaction.  This hint is not guaranteed to be accurate but it
   1.888 +** is often close.  The underlying VFS might choose to preallocate database
   1.889 +** file space based on this hint in order to help writes to the database
   1.890 +** file run faster.
   1.891 +**
   1.892 +** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
   1.893 +** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
   1.894 +** extends and truncates the database file in chunks of a size specified
   1.895 +** by the user. The fourth argument to [sqlite3_file_control()] should 
   1.896 +** point to an integer (type int) containing the new chunk-size to use
   1.897 +** for the nominated database. Allocating database file space in large
   1.898 +** chunks (say 1MB at a time), may reduce file-system fragmentation and
   1.899 +** improve performance on some systems.
   1.900 +**
   1.901 +** <li>[[SQLITE_FCNTL_FILE_POINTER]]
   1.902 +** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
   1.903 +** to the [sqlite3_file] object associated with a particular database
   1.904 +** connection.  See the [sqlite3_file_control()] documentation for
   1.905 +** additional information.
   1.906 +**
   1.907 +** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
   1.908 +** No longer in use.
   1.909 +**
   1.910 +** <li>[[SQLITE_FCNTL_SYNC]]
   1.911 +** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
   1.912 +** sent to the VFS immediately before the xSync method is invoked on a
   1.913 +** database file descriptor. Or, if the xSync method is not invoked 
   1.914 +** because the user has configured SQLite with 
   1.915 +** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 
   1.916 +** of the xSync method. In most cases, the pointer argument passed with
   1.917 +** this file-control is NULL. However, if the database file is being synced
   1.918 +** as part of a multi-database commit, the argument points to a nul-terminated
   1.919 +** string containing the transactions master-journal file name. VFSes that 
   1.920 +** do not need this signal should silently ignore this opcode. Applications 
   1.921 +** should not call [sqlite3_file_control()] with this opcode as doing so may 
   1.922 +** disrupt the operation of the specialized VFSes that do require it.  
   1.923 +**
   1.924 +** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
   1.925 +** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
   1.926 +** and sent to the VFS after a transaction has been committed immediately
   1.927 +** but before the database is unlocked. VFSes that do not need this signal
   1.928 +** should silently ignore this opcode. Applications should not call
   1.929 +** [sqlite3_file_control()] with this opcode as doing so may disrupt the 
   1.930 +** operation of the specialized VFSes that do require it.  
   1.931 +**
   1.932 +** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
   1.933 +** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
   1.934 +** retry counts and intervals for certain disk I/O operations for the
   1.935 +** windows [VFS] in order to provide robustness in the presence of
   1.936 +** anti-virus programs.  By default, the windows VFS will retry file read,
   1.937 +** file write, and file delete operations up to 10 times, with a delay
   1.938 +** of 25 milliseconds before the first retry and with the delay increasing
   1.939 +** by an additional 25 milliseconds with each subsequent retry.  This
   1.940 +** opcode allows these two values (10 retries and 25 milliseconds of delay)
   1.941 +** to be adjusted.  The values are changed for all database connections
   1.942 +** within the same process.  The argument is a pointer to an array of two
   1.943 +** integers where the first integer i the new retry count and the second
   1.944 +** integer is the delay.  If either integer is negative, then the setting
   1.945 +** is not changed but instead the prior value of that setting is written
   1.946 +** into the array entry, allowing the current retry settings to be
   1.947 +** interrogated.  The zDbName parameter is ignored.
   1.948 +**
   1.949 +** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
   1.950 +** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
   1.951 +** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
   1.952 +** write ahead log and shared memory files used for transaction control
   1.953 +** are automatically deleted when the latest connection to the database
   1.954 +** closes.  Setting persistent WAL mode causes those files to persist after
   1.955 +** close.  Persisting the files is useful when other processes that do not
   1.956 +** have write permission on the directory containing the database file want
   1.957 +** to read the database file, as the WAL and shared memory files must exist
   1.958 +** in order for the database to be readable.  The fourth parameter to
   1.959 +** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
   1.960 +** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
   1.961 +** WAL mode.  If the integer is -1, then it is overwritten with the current
   1.962 +** WAL persistence setting.
   1.963 +**
   1.964 +** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
   1.965 +** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
   1.966 +** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
   1.967 +** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
   1.968 +** xDeviceCharacteristics methods. The fourth parameter to
   1.969 +** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
   1.970 +** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
   1.971 +** mode.  If the integer is -1, then it is overwritten with the current
   1.972 +** zero-damage mode setting.
   1.973 +**
   1.974 +** <li>[[SQLITE_FCNTL_OVERWRITE]]
   1.975 +** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
   1.976 +** a write transaction to indicate that, unless it is rolled back for some
   1.977 +** reason, the entire database file will be overwritten by the current 
   1.978 +** transaction. This is used by VACUUM operations.
   1.979 +**
   1.980 +** <li>[[SQLITE_FCNTL_VFSNAME]]
   1.981 +** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
   1.982 +** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
   1.983 +** final bottom-level VFS are written into memory obtained from 
   1.984 +** [sqlite3_malloc()] and the result is stored in the char* variable
   1.985 +** that the fourth parameter of [sqlite3_file_control()] points to.
   1.986 +** The caller is responsible for freeing the memory when done.  As with
   1.987 +** all file-control actions, there is no guarantee that this will actually
   1.988 +** do anything.  Callers should initialize the char* variable to a NULL
   1.989 +** pointer in case this file-control is not implemented.  This file-control
   1.990 +** is intended for diagnostic use only.
   1.991 +**
   1.992 +** <li>[[SQLITE_FCNTL_PRAGMA]]
   1.993 +** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 
   1.994 +** file control is sent to the open [sqlite3_file] object corresponding
   1.995 +** to the database file to which the pragma statement refers. ^The argument
   1.996 +** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
   1.997 +** pointers to strings (char**) in which the second element of the array
   1.998 +** is the name of the pragma and the third element is the argument to the
   1.999 +** pragma or NULL if the pragma has no argument.  ^The handler for an
  1.1000 +** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
  1.1001 +** of the char** argument point to a string obtained from [sqlite3_mprintf()]
  1.1002 +** or the equivalent and that string will become the result of the pragma or
  1.1003 +** the error message if the pragma fails. ^If the
  1.1004 +** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 
  1.1005 +** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
  1.1006 +** file control returns [SQLITE_OK], then the parser assumes that the
  1.1007 +** VFS has handled the PRAGMA itself and the parser generates a no-op
  1.1008 +** prepared statement.  ^If the [SQLITE_FCNTL_PRAGMA] file control returns
  1.1009 +** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
  1.1010 +** that the VFS encountered an error while handling the [PRAGMA] and the
  1.1011 +** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
  1.1012 +** file control occurs at the beginning of pragma statement analysis and so
  1.1013 +** it is able to override built-in [PRAGMA] statements.
  1.1014 +**
  1.1015 +** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
  1.1016 +** ^The [SQLITE_FCNTL_BUSYHANDLER]
  1.1017 +** file-control may be invoked by SQLite on the database file handle
  1.1018 +** shortly after it is opened in order to provide a custom VFS with access
  1.1019 +** to the connections busy-handler callback. The argument is of type (void **)
  1.1020 +** - an array of two (void *) values. The first (void *) actually points
  1.1021 +** to a function of type (int (*)(void *)). In order to invoke the connections
  1.1022 +** busy-handler, this function should be invoked with the second (void *) in
  1.1023 +** the array as the only argument. If it returns non-zero, then the operation
  1.1024 +** should be retried. If it returns zero, the custom VFS should abandon the
  1.1025 +** current operation.
  1.1026 +**
  1.1027 +** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
  1.1028 +** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
  1.1029 +** to have SQLite generate a
  1.1030 +** temporary filename using the same algorithm that is followed to generate
  1.1031 +** temporary filenames for TEMP tables and other internal uses.  The
  1.1032 +** argument should be a char** which will be filled with the filename
  1.1033 +** written into memory obtained from [sqlite3_malloc()].  The caller should
  1.1034 +** invoke [sqlite3_free()] on the result to avoid a memory leak.
  1.1035 +**
  1.1036 +** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
  1.1037 +** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
  1.1038 +** maximum number of bytes that will be used for memory-mapped I/O.
  1.1039 +** The argument is a pointer to a value of type sqlite3_int64 that
  1.1040 +** is an advisory maximum number of bytes in the file to memory map.  The
  1.1041 +** pointer is overwritten with the old value.  The limit is not changed if
  1.1042 +** the value originally pointed to is negative, and so the current limit 
  1.1043 +** can be queried by passing in a pointer to a negative number.  This
  1.1044 +** file-control is used internally to implement [PRAGMA mmap_size].
  1.1045 +**
  1.1046 +** <li>[[SQLITE_FCNTL_TRACE]]
  1.1047 +** The [SQLITE_FCNTL_TRACE] file control provides advisory information
  1.1048 +** to the VFS about what the higher layers of the SQLite stack are doing.
  1.1049 +** This file control is used by some VFS activity tracing [shims].
  1.1050 +** The argument is a zero-terminated string.  Higher layers in the
  1.1051 +** SQLite stack may generate instances of this file control if
  1.1052 +** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
  1.1053 +**
  1.1054 +** <li>[[SQLITE_FCNTL_HAS_MOVED]]
  1.1055 +** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
  1.1056 +** pointer to an integer and it writes a boolean into that integer depending
  1.1057 +** on whether or not the file has been renamed, moved, or deleted since it
  1.1058 +** was first opened.
  1.1059 +**
  1.1060 +** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
  1.1061 +** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
  1.1062 +** opcode causes the xFileControl method to swap the file handle with the one
  1.1063 +** pointed to by the pArg argument.  This capability is used during testing
  1.1064 +** and only needs to be supported when SQLITE_TEST is defined.
  1.1065 +**
  1.1066 +** </ul>
  1.1067 +*/
  1.1068 +#define SQLITE_FCNTL_LOCKSTATE               1
  1.1069 +#define SQLITE_GET_LOCKPROXYFILE             2
  1.1070 +#define SQLITE_SET_LOCKPROXYFILE             3
  1.1071 +#define SQLITE_LAST_ERRNO                    4
  1.1072 +#define SQLITE_FCNTL_SIZE_HINT               5
  1.1073 +#define SQLITE_FCNTL_CHUNK_SIZE              6
  1.1074 +#define SQLITE_FCNTL_FILE_POINTER            7
  1.1075 +#define SQLITE_FCNTL_SYNC_OMITTED            8
  1.1076 +#define SQLITE_FCNTL_WIN32_AV_RETRY          9
  1.1077 +#define SQLITE_FCNTL_PERSIST_WAL            10
  1.1078 +#define SQLITE_FCNTL_OVERWRITE              11
  1.1079 +#define SQLITE_FCNTL_VFSNAME                12
  1.1080 +#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
  1.1081 +#define SQLITE_FCNTL_PRAGMA                 14
  1.1082 +#define SQLITE_FCNTL_BUSYHANDLER            15
  1.1083 +#define SQLITE_FCNTL_TEMPFILENAME           16
  1.1084 +#define SQLITE_FCNTL_MMAP_SIZE              18
  1.1085 +#define SQLITE_FCNTL_TRACE                  19
  1.1086 +#define SQLITE_FCNTL_HAS_MOVED              20
  1.1087 +#define SQLITE_FCNTL_SYNC                   21
  1.1088 +#define SQLITE_FCNTL_COMMIT_PHASETWO        22
  1.1089 +#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
  1.1090 +
  1.1091 +/*
  1.1092 +** CAPI3REF: Mutex Handle
  1.1093 +**
  1.1094 +** The mutex module within SQLite defines [sqlite3_mutex] to be an
  1.1095 +** abstract type for a mutex object.  The SQLite core never looks
  1.1096 +** at the internal representation of an [sqlite3_mutex].  It only
  1.1097 +** deals with pointers to the [sqlite3_mutex] object.
  1.1098 +**
  1.1099 +** Mutexes are created using [sqlite3_mutex_alloc()].
  1.1100 +*/
  1.1101 +typedef struct sqlite3_mutex sqlite3_mutex;
  1.1102 +
  1.1103 +/*
  1.1104 +** CAPI3REF: OS Interface Object
  1.1105 +**
  1.1106 +** An instance of the sqlite3_vfs object defines the interface between
  1.1107 +** the SQLite core and the underlying operating system.  The "vfs"
  1.1108 +** in the name of the object stands for "virtual file system".  See
  1.1109 +** the [VFS | VFS documentation] for further information.
  1.1110 +**
  1.1111 +** The value of the iVersion field is initially 1 but may be larger in
  1.1112 +** future versions of SQLite.  Additional fields may be appended to this
  1.1113 +** object when the iVersion value is increased.  Note that the structure
  1.1114 +** of the sqlite3_vfs object changes in the transaction between
  1.1115 +** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
  1.1116 +** modified.
  1.1117 +**
  1.1118 +** The szOsFile field is the size of the subclassed [sqlite3_file]
  1.1119 +** structure used by this VFS.  mxPathname is the maximum length of
  1.1120 +** a pathname in this VFS.
  1.1121 +**
  1.1122 +** Registered sqlite3_vfs objects are kept on a linked list formed by
  1.1123 +** the pNext pointer.  The [sqlite3_vfs_register()]
  1.1124 +** and [sqlite3_vfs_unregister()] interfaces manage this list
  1.1125 +** in a thread-safe way.  The [sqlite3_vfs_find()] interface
  1.1126 +** searches the list.  Neither the application code nor the VFS
  1.1127 +** implementation should use the pNext pointer.
  1.1128 +**
  1.1129 +** The pNext field is the only field in the sqlite3_vfs
  1.1130 +** structure that SQLite will ever modify.  SQLite will only access
  1.1131 +** or modify this field while holding a particular static mutex.
  1.1132 +** The application should never modify anything within the sqlite3_vfs
  1.1133 +** object once the object has been registered.
  1.1134 +**
  1.1135 +** The zName field holds the name of the VFS module.  The name must
  1.1136 +** be unique across all VFS modules.
  1.1137 +**
  1.1138 +** [[sqlite3_vfs.xOpen]]
  1.1139 +** ^SQLite guarantees that the zFilename parameter to xOpen
  1.1140 +** is either a NULL pointer or string obtained
  1.1141 +** from xFullPathname() with an optional suffix added.
  1.1142 +** ^If a suffix is added to the zFilename parameter, it will
  1.1143 +** consist of a single "-" character followed by no more than
  1.1144 +** 11 alphanumeric and/or "-" characters.
  1.1145 +** ^SQLite further guarantees that
  1.1146 +** the string will be valid and unchanged until xClose() is
  1.1147 +** called. Because of the previous sentence,
  1.1148 +** the [sqlite3_file] can safely store a pointer to the
  1.1149 +** filename if it needs to remember the filename for some reason.
  1.1150 +** If the zFilename parameter to xOpen is a NULL pointer then xOpen
  1.1151 +** must invent its own temporary name for the file.  ^Whenever the 
  1.1152 +** xFilename parameter is NULL it will also be the case that the
  1.1153 +** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
  1.1154 +**
  1.1155 +** The flags argument to xOpen() includes all bits set in
  1.1156 +** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
  1.1157 +** or [sqlite3_open16()] is used, then flags includes at least
  1.1158 +** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 
  1.1159 +** If xOpen() opens a file read-only then it sets *pOutFlags to
  1.1160 +** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
  1.1161 +**
  1.1162 +** ^(SQLite will also add one of the following flags to the xOpen()
  1.1163 +** call, depending on the object being opened:
  1.1164 +**
  1.1165 +** <ul>
  1.1166 +** <li>  [SQLITE_OPEN_MAIN_DB]
  1.1167 +** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
  1.1168 +** <li>  [SQLITE_OPEN_TEMP_DB]
  1.1169 +** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
  1.1170 +** <li>  [SQLITE_OPEN_TRANSIENT_DB]
  1.1171 +** <li>  [SQLITE_OPEN_SUBJOURNAL]
  1.1172 +** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
  1.1173 +** <li>  [SQLITE_OPEN_WAL]
  1.1174 +** </ul>)^
  1.1175 +**
  1.1176 +** The file I/O implementation can use the object type flags to
  1.1177 +** change the way it deals with files.  For example, an application
  1.1178 +** that does not care about crash recovery or rollback might make
  1.1179 +** the open of a journal file a no-op.  Writes to this journal would
  1.1180 +** also be no-ops, and any attempt to read the journal would return
  1.1181 +** SQLITE_IOERR.  Or the implementation might recognize that a database
  1.1182 +** file will be doing page-aligned sector reads and writes in a random
  1.1183 +** order and set up its I/O subsystem accordingly.
  1.1184 +**
  1.1185 +** SQLite might also add one of the following flags to the xOpen method:
  1.1186 +**
  1.1187 +** <ul>
  1.1188 +** <li> [SQLITE_OPEN_DELETEONCLOSE]
  1.1189 +** <li> [SQLITE_OPEN_EXCLUSIVE]
  1.1190 +** </ul>
  1.1191 +**
  1.1192 +** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
  1.1193 +** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
  1.1194 +** will be set for TEMP databases and their journals, transient
  1.1195 +** databases, and subjournals.
  1.1196 +**
  1.1197 +** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
  1.1198 +** with the [SQLITE_OPEN_CREATE] flag, which are both directly
  1.1199 +** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
  1.1200 +** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
  1.1201 +** SQLITE_OPEN_CREATE, is used to indicate that file should always
  1.1202 +** be created, and that it is an error if it already exists.
  1.1203 +** It is <i>not</i> used to indicate the file should be opened 
  1.1204 +** for exclusive access.
  1.1205 +**
  1.1206 +** ^At least szOsFile bytes of memory are allocated by SQLite
  1.1207 +** to hold the  [sqlite3_file] structure passed as the third
  1.1208 +** argument to xOpen.  The xOpen method does not have to
  1.1209 +** allocate the structure; it should just fill it in.  Note that
  1.1210 +** the xOpen method must set the sqlite3_file.pMethods to either
  1.1211 +** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
  1.1212 +** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
  1.1213 +** element will be valid after xOpen returns regardless of the success
  1.1214 +** or failure of the xOpen call.
  1.1215 +**
  1.1216 +** [[sqlite3_vfs.xAccess]]
  1.1217 +** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
  1.1218 +** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
  1.1219 +** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
  1.1220 +** to test whether a file is at least readable.   The file can be a
  1.1221 +** directory.
  1.1222 +**
  1.1223 +** ^SQLite will always allocate at least mxPathname+1 bytes for the
  1.1224 +** output buffer xFullPathname.  The exact size of the output buffer
  1.1225 +** is also passed as a parameter to both  methods. If the output buffer
  1.1226 +** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
  1.1227 +** handled as a fatal error by SQLite, vfs implementations should endeavor
  1.1228 +** to prevent this by setting mxPathname to a sufficiently large value.
  1.1229 +**
  1.1230 +** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
  1.1231 +** interfaces are not strictly a part of the filesystem, but they are
  1.1232 +** included in the VFS structure for completeness.
  1.1233 +** The xRandomness() function attempts to return nBytes bytes
  1.1234 +** of good-quality randomness into zOut.  The return value is
  1.1235 +** the actual number of bytes of randomness obtained.
  1.1236 +** The xSleep() method causes the calling thread to sleep for at
  1.1237 +** least the number of microseconds given.  ^The xCurrentTime()
  1.1238 +** method returns a Julian Day Number for the current date and time as
  1.1239 +** a floating point value.
  1.1240 +** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
  1.1241 +** Day Number multiplied by 86400000 (the number of milliseconds in 
  1.1242 +** a 24-hour day).  
  1.1243 +** ^SQLite will use the xCurrentTimeInt64() method to get the current
  1.1244 +** date and time if that method is available (if iVersion is 2 or 
  1.1245 +** greater and the function pointer is not NULL) and will fall back
  1.1246 +** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
  1.1247 +**
  1.1248 +** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
  1.1249 +** are not used by the SQLite core.  These optional interfaces are provided
  1.1250 +** by some VFSes to facilitate testing of the VFS code. By overriding 
  1.1251 +** system calls with functions under its control, a test program can
  1.1252 +** simulate faults and error conditions that would otherwise be difficult
  1.1253 +** or impossible to induce.  The set of system calls that can be overridden
  1.1254 +** varies from one VFS to another, and from one version of the same VFS to the
  1.1255 +** next.  Applications that use these interfaces must be prepared for any
  1.1256 +** or all of these interfaces to be NULL or for their behavior to change
  1.1257 +** from one release to the next.  Applications must not attempt to access
  1.1258 +** any of these methods if the iVersion of the VFS is less than 3.
  1.1259 +*/
  1.1260 +typedef struct sqlite3_vfs sqlite3_vfs;
  1.1261 +typedef void (*sqlite3_syscall_ptr)(void);
  1.1262 +struct sqlite3_vfs {
  1.1263 +  int iVersion;            /* Structure version number (currently 3) */
  1.1264 +  int szOsFile;            /* Size of subclassed sqlite3_file */
  1.1265 +  int mxPathname;          /* Maximum file pathname length */
  1.1266 +  sqlite3_vfs *pNext;      /* Next registered VFS */
  1.1267 +  const char *zName;       /* Name of this virtual file system */
  1.1268 +  void *pAppData;          /* Pointer to application-specific data */
  1.1269 +  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
  1.1270 +               int flags, int *pOutFlags);
  1.1271 +  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
  1.1272 +  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
  1.1273 +  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
  1.1274 +  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
  1.1275 +  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
  1.1276 +  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
  1.1277 +  void (*xDlClose)(sqlite3_vfs*, void*);
  1.1278 +  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
  1.1279 +  int (*xSleep)(sqlite3_vfs*, int microseconds);
  1.1280 +  int (*xCurrentTime)(sqlite3_vfs*, double*);
  1.1281 +  int (*xGetLastError)(sqlite3_vfs*, int, char *);
  1.1282 +  /*
  1.1283 +  ** The methods above are in version 1 of the sqlite_vfs object
  1.1284 +  ** definition.  Those that follow are added in version 2 or later
  1.1285 +  */
  1.1286 +  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
  1.1287 +  /*
  1.1288 +  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
  1.1289 +  ** Those below are for version 3 and greater.
  1.1290 +  */
  1.1291 +  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
  1.1292 +  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
  1.1293 +  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
  1.1294 +  /*
  1.1295 +  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
  1.1296 +  ** New fields may be appended in figure versions.  The iVersion
  1.1297 +  ** value will increment whenever this happens. 
  1.1298 +  */
  1.1299 +};
  1.1300 +
  1.1301 +/*
  1.1302 +** CAPI3REF: Flags for the xAccess VFS method
  1.1303 +**
  1.1304 +** These integer constants can be used as the third parameter to
  1.1305 +** the xAccess method of an [sqlite3_vfs] object.  They determine
  1.1306 +** what kind of permissions the xAccess method is looking for.
  1.1307 +** With SQLITE_ACCESS_EXISTS, the xAccess method
  1.1308 +** simply checks whether the file exists.
  1.1309 +** With SQLITE_ACCESS_READWRITE, the xAccess method
  1.1310 +** checks whether the named directory is both readable and writable
  1.1311 +** (in other words, if files can be added, removed, and renamed within
  1.1312 +** the directory).
  1.1313 +** The SQLITE_ACCESS_READWRITE constant is currently used only by the
  1.1314 +** [temp_store_directory pragma], though this could change in a future
  1.1315 +** release of SQLite.
  1.1316 +** With SQLITE_ACCESS_READ, the xAccess method
  1.1317 +** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
  1.1318 +** currently unused, though it might be used in a future release of
  1.1319 +** SQLite.
  1.1320 +*/
  1.1321 +#define SQLITE_ACCESS_EXISTS    0
  1.1322 +#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
  1.1323 +#define SQLITE_ACCESS_READ      2   /* Unused */
  1.1324 +
  1.1325 +/*
  1.1326 +** CAPI3REF: Flags for the xShmLock VFS method
  1.1327 +**
  1.1328 +** These integer constants define the various locking operations
  1.1329 +** allowed by the xShmLock method of [sqlite3_io_methods].  The
  1.1330 +** following are the only legal combinations of flags to the
  1.1331 +** xShmLock method:
  1.1332 +**
  1.1333 +** <ul>
  1.1334 +** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
  1.1335 +** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
  1.1336 +** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
  1.1337 +** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
  1.1338 +** </ul>
  1.1339 +**
  1.1340 +** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
  1.1341 +** was given no the corresponding lock.  
  1.1342 +**
  1.1343 +** The xShmLock method can transition between unlocked and SHARED or
  1.1344 +** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
  1.1345 +** and EXCLUSIVE.
  1.1346 +*/
  1.1347 +#define SQLITE_SHM_UNLOCK       1
  1.1348 +#define SQLITE_SHM_LOCK         2
  1.1349 +#define SQLITE_SHM_SHARED       4
  1.1350 +#define SQLITE_SHM_EXCLUSIVE    8
  1.1351 +
  1.1352 +/*
  1.1353 +** CAPI3REF: Maximum xShmLock index
  1.1354 +**
  1.1355 +** The xShmLock method on [sqlite3_io_methods] may use values
  1.1356 +** between 0 and this upper bound as its "offset" argument.
  1.1357 +** The SQLite core will never attempt to acquire or release a
  1.1358 +** lock outside of this range
  1.1359 +*/
  1.1360 +#define SQLITE_SHM_NLOCK        8
  1.1361 +
  1.1362 +
  1.1363 +/*
  1.1364 +** CAPI3REF: Initialize The SQLite Library
  1.1365 +**
  1.1366 +** ^The sqlite3_initialize() routine initializes the
  1.1367 +** SQLite library.  ^The sqlite3_shutdown() routine
  1.1368 +** deallocates any resources that were allocated by sqlite3_initialize().
  1.1369 +** These routines are designed to aid in process initialization and
  1.1370 +** shutdown on embedded systems.  Workstation applications using
  1.1371 +** SQLite normally do not need to invoke either of these routines.
  1.1372 +**
  1.1373 +** A call to sqlite3_initialize() is an "effective" call if it is
  1.1374 +** the first time sqlite3_initialize() is invoked during the lifetime of
  1.1375 +** the process, or if it is the first time sqlite3_initialize() is invoked
  1.1376 +** following a call to sqlite3_shutdown().  ^(Only an effective call
  1.1377 +** of sqlite3_initialize() does any initialization.  All other calls
  1.1378 +** are harmless no-ops.)^
  1.1379 +**
  1.1380 +** A call to sqlite3_shutdown() is an "effective" call if it is the first
  1.1381 +** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
  1.1382 +** an effective call to sqlite3_shutdown() does any deinitialization.
  1.1383 +** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
  1.1384 +**
  1.1385 +** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
  1.1386 +** is not.  The sqlite3_shutdown() interface must only be called from a
  1.1387 +** single thread.  All open [database connections] must be closed and all
  1.1388 +** other SQLite resources must be deallocated prior to invoking
  1.1389 +** sqlite3_shutdown().
  1.1390 +**
  1.1391 +** Among other things, ^sqlite3_initialize() will invoke
  1.1392 +** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
  1.1393 +** will invoke sqlite3_os_end().
  1.1394 +**
  1.1395 +** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
  1.1396 +** ^If for some reason, sqlite3_initialize() is unable to initialize
  1.1397 +** the library (perhaps it is unable to allocate a needed resource such
  1.1398 +** as a mutex) it returns an [error code] other than [SQLITE_OK].
  1.1399 +**
  1.1400 +** ^The sqlite3_initialize() routine is called internally by many other
  1.1401 +** SQLite interfaces so that an application usually does not need to
  1.1402 +** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
  1.1403 +** calls sqlite3_initialize() so the SQLite library will be automatically
  1.1404 +** initialized when [sqlite3_open()] is called if it has not be initialized
  1.1405 +** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
  1.1406 +** compile-time option, then the automatic calls to sqlite3_initialize()
  1.1407 +** are omitted and the application must call sqlite3_initialize() directly
  1.1408 +** prior to using any other SQLite interface.  For maximum portability,
  1.1409 +** it is recommended that applications always invoke sqlite3_initialize()
  1.1410 +** directly prior to using any other SQLite interface.  Future releases
  1.1411 +** of SQLite may require this.  In other words, the behavior exhibited
  1.1412 +** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
  1.1413 +** default behavior in some future release of SQLite.
  1.1414 +**
  1.1415 +** The sqlite3_os_init() routine does operating-system specific
  1.1416 +** initialization of the SQLite library.  The sqlite3_os_end()
  1.1417 +** routine undoes the effect of sqlite3_os_init().  Typical tasks
  1.1418 +** performed by these routines include allocation or deallocation
  1.1419 +** of static resources, initialization of global variables,
  1.1420 +** setting up a default [sqlite3_vfs] module, or setting up
  1.1421 +** a default configuration using [sqlite3_config()].
  1.1422 +**
  1.1423 +** The application should never invoke either sqlite3_os_init()
  1.1424 +** or sqlite3_os_end() directly.  The application should only invoke
  1.1425 +** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
  1.1426 +** interface is called automatically by sqlite3_initialize() and
  1.1427 +** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
  1.1428 +** implementations for sqlite3_os_init() and sqlite3_os_end()
  1.1429 +** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
  1.1430 +** When [custom builds | built for other platforms]
  1.1431 +** (using the [SQLITE_OS_OTHER=1] compile-time
  1.1432 +** option) the application must supply a suitable implementation for
  1.1433 +** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
  1.1434 +** implementation of sqlite3_os_init() or sqlite3_os_end()
  1.1435 +** must return [SQLITE_OK] on success and some other [error code] upon
  1.1436 +** failure.
  1.1437 +*/
  1.1438 +SQLITE_API int sqlite3_initialize(void);
  1.1439 +SQLITE_API int sqlite3_shutdown(void);
  1.1440 +SQLITE_API int sqlite3_os_init(void);
  1.1441 +SQLITE_API int sqlite3_os_end(void);
  1.1442 +
  1.1443 +/*
  1.1444 +** CAPI3REF: Configuring The SQLite Library
  1.1445 +**
  1.1446 +** The sqlite3_config() interface is used to make global configuration
  1.1447 +** changes to SQLite in order to tune SQLite to the specific needs of
  1.1448 +** the application.  The default configuration is recommended for most
  1.1449 +** applications and so this routine is usually not necessary.  It is
  1.1450 +** provided to support rare applications with unusual needs.
  1.1451 +**
  1.1452 +** The sqlite3_config() interface is not threadsafe.  The application
  1.1453 +** must insure that no other SQLite interfaces are invoked by other
  1.1454 +** threads while sqlite3_config() is running.  Furthermore, sqlite3_config()
  1.1455 +** may only be invoked prior to library initialization using
  1.1456 +** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
  1.1457 +** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
  1.1458 +** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
  1.1459 +** Note, however, that ^sqlite3_config() can be called as part of the
  1.1460 +** implementation of an application-defined [sqlite3_os_init()].
  1.1461 +**
  1.1462 +** The first argument to sqlite3_config() is an integer
  1.1463 +** [configuration option] that determines
  1.1464 +** what property of SQLite is to be configured.  Subsequent arguments
  1.1465 +** vary depending on the [configuration option]
  1.1466 +** in the first argument.
  1.1467 +**
  1.1468 +** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
  1.1469 +** ^If the option is unknown or SQLite is unable to set the option
  1.1470 +** then this routine returns a non-zero [error code].
  1.1471 +*/
  1.1472 +SQLITE_API int sqlite3_config(int, ...);
  1.1473 +
  1.1474 +/*
  1.1475 +** CAPI3REF: Configure database connections
  1.1476 +**
  1.1477 +** The sqlite3_db_config() interface is used to make configuration
  1.1478 +** changes to a [database connection].  The interface is similar to
  1.1479 +** [sqlite3_config()] except that the changes apply to a single
  1.1480 +** [database connection] (specified in the first argument).
  1.1481 +**
  1.1482 +** The second argument to sqlite3_db_config(D,V,...)  is the
  1.1483 +** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 
  1.1484 +** that indicates what aspect of the [database connection] is being configured.
  1.1485 +** Subsequent arguments vary depending on the configuration verb.
  1.1486 +**
  1.1487 +** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
  1.1488 +** the call is considered successful.
  1.1489 +*/
  1.1490 +SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
  1.1491 +
  1.1492 +/*
  1.1493 +** CAPI3REF: Memory Allocation Routines
  1.1494 +**
  1.1495 +** An instance of this object defines the interface between SQLite
  1.1496 +** and low-level memory allocation routines.
  1.1497 +**
  1.1498 +** This object is used in only one place in the SQLite interface.
  1.1499 +** A pointer to an instance of this object is the argument to
  1.1500 +** [sqlite3_config()] when the configuration option is
  1.1501 +** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].  
  1.1502 +** By creating an instance of this object
  1.1503 +** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
  1.1504 +** during configuration, an application can specify an alternative
  1.1505 +** memory allocation subsystem for SQLite to use for all of its
  1.1506 +** dynamic memory needs.
  1.1507 +**
  1.1508 +** Note that SQLite comes with several [built-in memory allocators]
  1.1509 +** that are perfectly adequate for the overwhelming majority of applications
  1.1510 +** and that this object is only useful to a tiny minority of applications
  1.1511 +** with specialized memory allocation requirements.  This object is
  1.1512 +** also used during testing of SQLite in order to specify an alternative
  1.1513 +** memory allocator that simulates memory out-of-memory conditions in
  1.1514 +** order to verify that SQLite recovers gracefully from such
  1.1515 +** conditions.
  1.1516 +**
  1.1517 +** The xMalloc, xRealloc, and xFree methods must work like the
  1.1518 +** malloc(), realloc() and free() functions from the standard C library.
  1.1519 +** ^SQLite guarantees that the second argument to
  1.1520 +** xRealloc is always a value returned by a prior call to xRoundup.
  1.1521 +**
  1.1522 +** xSize should return the allocated size of a memory allocation
  1.1523 +** previously obtained from xMalloc or xRealloc.  The allocated size
  1.1524 +** is always at least as big as the requested size but may be larger.
  1.1525 +**
  1.1526 +** The xRoundup method returns what would be the allocated size of
  1.1527 +** a memory allocation given a particular requested size.  Most memory
  1.1528 +** allocators round up memory allocations at least to the next multiple
  1.1529 +** of 8.  Some allocators round up to a larger multiple or to a power of 2.
  1.1530 +** Every memory allocation request coming in through [sqlite3_malloc()]
  1.1531 +** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0, 
  1.1532 +** that causes the corresponding memory allocation to fail.
  1.1533 +**
  1.1534 +** The xInit method initializes the memory allocator.  For example,
  1.1535 +** it might allocate any require mutexes or initialize internal data
  1.1536 +** structures.  The xShutdown method is invoked (indirectly) by
  1.1537 +** [sqlite3_shutdown()] and should deallocate any resources acquired
  1.1538 +** by xInit.  The pAppData pointer is used as the only parameter to
  1.1539 +** xInit and xShutdown.
  1.1540 +**
  1.1541 +** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
  1.1542 +** the xInit method, so the xInit method need not be threadsafe.  The
  1.1543 +** xShutdown method is only called from [sqlite3_shutdown()] so it does
  1.1544 +** not need to be threadsafe either.  For all other methods, SQLite
  1.1545 +** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
  1.1546 +** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
  1.1547 +** it is by default) and so the methods are automatically serialized.
  1.1548 +** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
  1.1549 +** methods must be threadsafe or else make their own arrangements for
  1.1550 +** serialization.
  1.1551 +**
  1.1552 +** SQLite will never invoke xInit() more than once without an intervening
  1.1553 +** call to xShutdown().
  1.1554 +*/
  1.1555 +typedef struct sqlite3_mem_methods sqlite3_mem_methods;
  1.1556 +struct sqlite3_mem_methods {
  1.1557 +  void *(*xMalloc)(int);         /* Memory allocation function */
  1.1558 +  void (*xFree)(void*);          /* Free a prior allocation */
  1.1559 +  void *(*xRealloc)(void*,int);  /* Resize an allocation */
  1.1560 +  int (*xSize)(void*);           /* Return the size of an allocation */
  1.1561 +  int (*xRoundup)(int);          /* Round up request size to allocation size */
  1.1562 +  int (*xInit)(void*);           /* Initialize the memory allocator */
  1.1563 +  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
  1.1564 +  void *pAppData;                /* Argument to xInit() and xShutdown() */
  1.1565 +};
  1.1566 +
  1.1567 +/*
  1.1568 +** CAPI3REF: Configuration Options
  1.1569 +** KEYWORDS: {configuration option}
  1.1570 +**
  1.1571 +** These constants are the available integer configuration options that
  1.1572 +** can be passed as the first argument to the [sqlite3_config()] interface.
  1.1573 +**
  1.1574 +** New configuration options may be added in future releases of SQLite.
  1.1575 +** Existing configuration options might be discontinued.  Applications
  1.1576 +** should check the return code from [sqlite3_config()] to make sure that
  1.1577 +** the call worked.  The [sqlite3_config()] interface will return a
  1.1578 +** non-zero [error code] if a discontinued or unsupported configuration option
  1.1579 +** is invoked.
  1.1580 +**
  1.1581 +** <dl>
  1.1582 +** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
  1.1583 +** <dd>There are no arguments to this option.  ^This option sets the
  1.1584 +** [threading mode] to Single-thread.  In other words, it disables
  1.1585 +** all mutexing and puts SQLite into a mode where it can only be used
  1.1586 +** by a single thread.   ^If SQLite is compiled with
  1.1587 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
  1.1588 +** it is not possible to change the [threading mode] from its default
  1.1589 +** value of Single-thread and so [sqlite3_config()] will return 
  1.1590 +** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
  1.1591 +** configuration option.</dd>
  1.1592 +**
  1.1593 +** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
  1.1594 +** <dd>There are no arguments to this option.  ^This option sets the
  1.1595 +** [threading mode] to Multi-thread.  In other words, it disables
  1.1596 +** mutexing on [database connection] and [prepared statement] objects.
  1.1597 +** The application is responsible for serializing access to
  1.1598 +** [database connections] and [prepared statements].  But other mutexes
  1.1599 +** are enabled so that SQLite will be safe to use in a multi-threaded
  1.1600 +** environment as long as no two threads attempt to use the same
  1.1601 +** [database connection] at the same time.  ^If SQLite is compiled with
  1.1602 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
  1.1603 +** it is not possible to set the Multi-thread [threading mode] and
  1.1604 +** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
  1.1605 +** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
  1.1606 +**
  1.1607 +** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
  1.1608 +** <dd>There are no arguments to this option.  ^This option sets the
  1.1609 +** [threading mode] to Serialized. In other words, this option enables
  1.1610 +** all mutexes including the recursive
  1.1611 +** mutexes on [database connection] and [prepared statement] objects.
  1.1612 +** In this mode (which is the default when SQLite is compiled with
  1.1613 +** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
  1.1614 +** to [database connections] and [prepared statements] so that the
  1.1615 +** application is free to use the same [database connection] or the
  1.1616 +** same [prepared statement] in different threads at the same time.
  1.1617 +** ^If SQLite is compiled with
  1.1618 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
  1.1619 +** it is not possible to set the Serialized [threading mode] and
  1.1620 +** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
  1.1621 +** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
  1.1622 +**
  1.1623 +** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
  1.1624 +** <dd> ^(This option takes a single argument which is a pointer to an
  1.1625 +** instance of the [sqlite3_mem_methods] structure.  The argument specifies
  1.1626 +** alternative low-level memory allocation routines to be used in place of
  1.1627 +** the memory allocation routines built into SQLite.)^ ^SQLite makes
  1.1628 +** its own private copy of the content of the [sqlite3_mem_methods] structure
  1.1629 +** before the [sqlite3_config()] call returns.</dd>
  1.1630 +**
  1.1631 +** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
  1.1632 +** <dd> ^(This option takes a single argument which is a pointer to an
  1.1633 +** instance of the [sqlite3_mem_methods] structure.  The [sqlite3_mem_methods]
  1.1634 +** structure is filled with the currently defined memory allocation routines.)^
  1.1635 +** This option can be used to overload the default memory allocation
  1.1636 +** routines with a wrapper that simulations memory allocation failure or
  1.1637 +** tracks memory usage, for example. </dd>
  1.1638 +**
  1.1639 +** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
  1.1640 +** <dd> ^This option takes single argument of type int, interpreted as a 
  1.1641 +** boolean, which enables or disables the collection of memory allocation 
  1.1642 +** statistics. ^(When memory allocation statistics are disabled, the 
  1.1643 +** following SQLite interfaces become non-operational:
  1.1644 +**   <ul>
  1.1645 +**   <li> [sqlite3_memory_used()]
  1.1646 +**   <li> [sqlite3_memory_highwater()]
  1.1647 +**   <li> [sqlite3_soft_heap_limit64()]
  1.1648 +**   <li> [sqlite3_status()]
  1.1649 +**   </ul>)^
  1.1650 +** ^Memory allocation statistics are enabled by default unless SQLite is
  1.1651 +** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
  1.1652 +** allocation statistics are disabled by default.
  1.1653 +** </dd>
  1.1654 +**
  1.1655 +** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
  1.1656 +** <dd> ^This option specifies a static memory buffer that SQLite can use for
  1.1657 +** scratch memory.  There are three arguments:  A pointer an 8-byte
  1.1658 +** aligned memory buffer from which the scratch allocations will be
  1.1659 +** drawn, the size of each scratch allocation (sz),
  1.1660 +** and the maximum number of scratch allocations (N).  The sz
  1.1661 +** argument must be a multiple of 16.
  1.1662 +** The first argument must be a pointer to an 8-byte aligned buffer
  1.1663 +** of at least sz*N bytes of memory.
  1.1664 +** ^SQLite will use no more than two scratch buffers per thread.  So
  1.1665 +** N should be set to twice the expected maximum number of threads.
  1.1666 +** ^SQLite will never require a scratch buffer that is more than 6
  1.1667 +** times the database page size. ^If SQLite needs needs additional
  1.1668 +** scratch memory beyond what is provided by this configuration option, then 
  1.1669 +** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
  1.1670 +**
  1.1671 +** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
  1.1672 +** <dd> ^This option specifies a static memory buffer that SQLite can use for
  1.1673 +** the database page cache with the default page cache implementation.  
  1.1674 +** This configuration should not be used if an application-define page
  1.1675 +** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option.
  1.1676 +** There are three arguments to this option: A pointer to 8-byte aligned
  1.1677 +** memory, the size of each page buffer (sz), and the number of pages (N).
  1.1678 +** The sz argument should be the size of the largest database page
  1.1679 +** (a power of two between 512 and 32768) plus a little extra for each
  1.1680 +** page header.  ^The page header size is 20 to 40 bytes depending on
  1.1681 +** the host architecture.  ^It is harmless, apart from the wasted memory,
  1.1682 +** to make sz a little too large.  The first
  1.1683 +** argument should point to an allocation of at least sz*N bytes of memory.
  1.1684 +** ^SQLite will use the memory provided by the first argument to satisfy its
  1.1685 +** memory needs for the first N pages that it adds to cache.  ^If additional
  1.1686 +** page cache memory is needed beyond what is provided by this option, then
  1.1687 +** SQLite goes to [sqlite3_malloc()] for the additional storage space.
  1.1688 +** The pointer in the first argument must
  1.1689 +** be aligned to an 8-byte boundary or subsequent behavior of SQLite
  1.1690 +** will be undefined.</dd>
  1.1691 +**
  1.1692 +** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
  1.1693 +** <dd> ^This option specifies a static memory buffer that SQLite will use
  1.1694 +** for all of its dynamic memory allocation needs beyond those provided
  1.1695 +** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
  1.1696 +** There are three arguments: An 8-byte aligned pointer to the memory,
  1.1697 +** the number of bytes in the memory buffer, and the minimum allocation size.
  1.1698 +** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
  1.1699 +** to using its default memory allocator (the system malloc() implementation),
  1.1700 +** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
  1.1701 +** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
  1.1702 +** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
  1.1703 +** allocator is engaged to handle all of SQLites memory allocation needs.
  1.1704 +** The first pointer (the memory pointer) must be aligned to an 8-byte
  1.1705 +** boundary or subsequent behavior of SQLite will be undefined.
  1.1706 +** The minimum allocation size is capped at 2**12. Reasonable values
  1.1707 +** for the minimum allocation size are 2**5 through 2**8.</dd>
  1.1708 +**
  1.1709 +** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
  1.1710 +** <dd> ^(This option takes a single argument which is a pointer to an
  1.1711 +** instance of the [sqlite3_mutex_methods] structure.  The argument specifies
  1.1712 +** alternative low-level mutex routines to be used in place
  1.1713 +** the mutex routines built into SQLite.)^  ^SQLite makes a copy of the
  1.1714 +** content of the [sqlite3_mutex_methods] structure before the call to
  1.1715 +** [sqlite3_config()] returns. ^If SQLite is compiled with
  1.1716 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
  1.1717 +** the entire mutexing subsystem is omitted from the build and hence calls to
  1.1718 +** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
  1.1719 +** return [SQLITE_ERROR].</dd>
  1.1720 +**
  1.1721 +** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
  1.1722 +** <dd> ^(This option takes a single argument which is a pointer to an
  1.1723 +** instance of the [sqlite3_mutex_methods] structure.  The
  1.1724 +** [sqlite3_mutex_methods]
  1.1725 +** structure is filled with the currently defined mutex routines.)^
  1.1726 +** This option can be used to overload the default mutex allocation
  1.1727 +** routines with a wrapper used to track mutex usage for performance
  1.1728 +** profiling or testing, for example.   ^If SQLite is compiled with
  1.1729 +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
  1.1730 +** the entire mutexing subsystem is omitted from the build and hence calls to
  1.1731 +** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
  1.1732 +** return [SQLITE_ERROR].</dd>
  1.1733 +**
  1.1734 +** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
  1.1735 +** <dd> ^(This option takes two arguments that determine the default
  1.1736 +** memory allocation for the lookaside memory allocator on each
  1.1737 +** [database connection].  The first argument is the
  1.1738 +** size of each lookaside buffer slot and the second is the number of
  1.1739 +** slots allocated to each database connection.)^  ^(This option sets the
  1.1740 +** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
  1.1741 +** verb to [sqlite3_db_config()] can be used to change the lookaside
  1.1742 +** configuration on individual connections.)^ </dd>
  1.1743 +**
  1.1744 +** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
  1.1745 +** <dd> ^(This option takes a single argument which is a pointer to
  1.1746 +** an [sqlite3_pcache_methods2] object.  This object specifies the interface
  1.1747 +** to a custom page cache implementation.)^  ^SQLite makes a copy of the
  1.1748 +** object and uses it for page cache memory allocations.</dd>
  1.1749 +**
  1.1750 +** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
  1.1751 +** <dd> ^(This option takes a single argument which is a pointer to an
  1.1752 +** [sqlite3_pcache_methods2] object.  SQLite copies of the current
  1.1753 +** page cache implementation into that object.)^ </dd>
  1.1754 +**
  1.1755 +** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
  1.1756 +** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
  1.1757 +** global [error log].
  1.1758 +** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
  1.1759 +** function with a call signature of void(*)(void*,int,const char*), 
  1.1760 +** and a pointer to void. ^If the function pointer is not NULL, it is
  1.1761 +** invoked by [sqlite3_log()] to process each logging event.  ^If the
  1.1762 +** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
  1.1763 +** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
  1.1764 +** passed through as the first parameter to the application-defined logger
  1.1765 +** function whenever that function is invoked.  ^The second parameter to
  1.1766 +** the logger function is a copy of the first parameter to the corresponding
  1.1767 +** [sqlite3_log()] call and is intended to be a [result code] or an
  1.1768 +** [extended result code].  ^The third parameter passed to the logger is
  1.1769 +** log message after formatting via [sqlite3_snprintf()].
  1.1770 +** The SQLite logging interface is not reentrant; the logger function
  1.1771 +** supplied by the application must not invoke any SQLite interface.
  1.1772 +** In a multi-threaded application, the application-defined logger
  1.1773 +** function must be threadsafe. </dd>
  1.1774 +**
  1.1775 +** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
  1.1776 +** <dd>^(This option takes a single argument of type int. If non-zero, then
  1.1777 +** URI handling is globally enabled. If the parameter is zero, then URI handling
  1.1778 +** is globally disabled.)^ ^If URI handling is globally enabled, all filenames
  1.1779 +** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
  1.1780 +** specified as part of [ATTACH] commands are interpreted as URIs, regardless
  1.1781 +** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
  1.1782 +** connection is opened. ^If it is globally disabled, filenames are
  1.1783 +** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
  1.1784 +** database connection is opened. ^(By default, URI handling is globally
  1.1785 +** disabled. The default value may be changed by compiling with the
  1.1786 +** [SQLITE_USE_URI] symbol defined.)^
  1.1787 +**
  1.1788 +** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
  1.1789 +** <dd>^This option takes a single integer argument which is interpreted as
  1.1790 +** a boolean in order to enable or disable the use of covering indices for
  1.1791 +** full table scans in the query optimizer.  ^The default setting is determined
  1.1792 +** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
  1.1793 +** if that compile-time option is omitted.
  1.1794 +** The ability to disable the use of covering indices for full table scans
  1.1795 +** is because some incorrectly coded legacy applications might malfunction
  1.1796 +** when the optimization is enabled.  Providing the ability to
  1.1797 +** disable the optimization allows the older, buggy application code to work
  1.1798 +** without change even with newer versions of SQLite.
  1.1799 +**
  1.1800 +** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
  1.1801 +** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
  1.1802 +** <dd> These options are obsolete and should not be used by new code.
  1.1803 +** They are retained for backwards compatibility but are now no-ops.
  1.1804 +** </dd>
  1.1805 +**
  1.1806 +** [[SQLITE_CONFIG_SQLLOG]]
  1.1807 +** <dt>SQLITE_CONFIG_SQLLOG
  1.1808 +** <dd>This option is only available if sqlite is compiled with the
  1.1809 +** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
  1.1810 +** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
  1.1811 +** The second should be of type (void*). The callback is invoked by the library
  1.1812 +** in three separate circumstances, identified by the value passed as the
  1.1813 +** fourth parameter. If the fourth parameter is 0, then the database connection
  1.1814 +** passed as the second argument has just been opened. The third argument
  1.1815 +** points to a buffer containing the name of the main database file. If the
  1.1816 +** fourth parameter is 1, then the SQL statement that the third parameter
  1.1817 +** points to has just been executed. Or, if the fourth parameter is 2, then
  1.1818 +** the connection being passed as the second parameter is being closed. The
  1.1819 +** third parameter is passed NULL In this case.  An example of using this
  1.1820 +** configuration option can be seen in the "test_sqllog.c" source file in
  1.1821 +** the canonical SQLite source tree.</dd>
  1.1822 +**
  1.1823 +** [[SQLITE_CONFIG_MMAP_SIZE]]
  1.1824 +** <dt>SQLITE_CONFIG_MMAP_SIZE
  1.1825 +** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
  1.1826 +** that are the default mmap size limit (the default setting for
  1.1827 +** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
  1.1828 +** ^The default setting can be overridden by each database connection using
  1.1829 +** either the [PRAGMA mmap_size] command, or by using the
  1.1830 +** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
  1.1831 +** cannot be changed at run-time.  Nor may the maximum allowed mmap size
  1.1832 +** exceed the compile-time maximum mmap size set by the
  1.1833 +** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
  1.1834 +** ^If either argument to this option is negative, then that argument is
  1.1835 +** changed to its compile-time default.
  1.1836 +**
  1.1837 +** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
  1.1838 +** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
  1.1839 +** <dd>^This option is only available if SQLite is compiled for Windows
  1.1840 +** with the [SQLITE_WIN32_MALLOC] pre-processor macro defined.
  1.1841 +** SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
  1.1842 +** that specifies the maximum size of the created heap.
  1.1843 +** </dl>
  1.1844 +*/
  1.1845 +#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
  1.1846 +#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
  1.1847 +#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
  1.1848 +#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
  1.1849 +#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
  1.1850 +#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
  1.1851 +#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
  1.1852 +#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
  1.1853 +#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
  1.1854 +#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
  1.1855 +#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
  1.1856 +/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 
  1.1857 +#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
  1.1858 +#define SQLITE_CONFIG_PCACHE       14  /* no-op */
  1.1859 +#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
  1.1860 +#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
  1.1861 +#define SQLITE_CONFIG_URI          17  /* int */
  1.1862 +#define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
  1.1863 +#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
  1.1864 +#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
  1.1865 +#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
  1.1866 +#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
  1.1867 +#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
  1.1868 +
  1.1869 +/*
  1.1870 +** CAPI3REF: Database Connection Configuration Options
  1.1871 +**
  1.1872 +** These constants are the available integer configuration options that
  1.1873 +** can be passed as the second argument to the [sqlite3_db_config()] interface.
  1.1874 +**
  1.1875 +** New configuration options may be added in future releases of SQLite.
  1.1876 +** Existing configuration options might be discontinued.  Applications
  1.1877 +** should check the return code from [sqlite3_db_config()] to make sure that
  1.1878 +** the call worked.  ^The [sqlite3_db_config()] interface will return a
  1.1879 +** non-zero [error code] if a discontinued or unsupported configuration option
  1.1880 +** is invoked.
  1.1881 +**
  1.1882 +** <dl>
  1.1883 +** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
  1.1884 +** <dd> ^This option takes three additional arguments that determine the 
  1.1885 +** [lookaside memory allocator] configuration for the [database connection].
  1.1886 +** ^The first argument (the third parameter to [sqlite3_db_config()] is a
  1.1887 +** pointer to a memory buffer to use for lookaside memory.
  1.1888 +** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
  1.1889 +** may be NULL in which case SQLite will allocate the
  1.1890 +** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
  1.1891 +** size of each lookaside buffer slot.  ^The third argument is the number of
  1.1892 +** slots.  The size of the buffer in the first argument must be greater than
  1.1893 +** or equal to the product of the second and third arguments.  The buffer
  1.1894 +** must be aligned to an 8-byte boundary.  ^If the second argument to
  1.1895 +** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
  1.1896 +** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
  1.1897 +** configuration for a database connection can only be changed when that
  1.1898 +** connection is not currently using lookaside memory, or in other words
  1.1899 +** when the "current value" returned by
  1.1900 +** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
  1.1901 +** Any attempt to change the lookaside memory configuration when lookaside
  1.1902 +** memory is in use leaves the configuration unchanged and returns 
  1.1903 +** [SQLITE_BUSY].)^</dd>
  1.1904 +**
  1.1905 +** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
  1.1906 +** <dd> ^This option is used to enable or disable the enforcement of
  1.1907 +** [foreign key constraints].  There should be two additional arguments.
  1.1908 +** The first argument is an integer which is 0 to disable FK enforcement,
  1.1909 +** positive to enable FK enforcement or negative to leave FK enforcement
  1.1910 +** unchanged.  The second parameter is a pointer to an integer into which
  1.1911 +** is written 0 or 1 to indicate whether FK enforcement is off or on
  1.1912 +** following this call.  The second parameter may be a NULL pointer, in
  1.1913 +** which case the FK enforcement setting is not reported back. </dd>
  1.1914 +**
  1.1915 +** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
  1.1916 +** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
  1.1917 +** There should be two additional arguments.
  1.1918 +** The first argument is an integer which is 0 to disable triggers,
  1.1919 +** positive to enable triggers or negative to leave the setting unchanged.
  1.1920 +** The second parameter is a pointer to an integer into which
  1.1921 +** is written 0 or 1 to indicate whether triggers are disabled or enabled
  1.1922 +** following this call.  The second parameter may be a NULL pointer, in
  1.1923 +** which case the trigger setting is not reported back. </dd>
  1.1924 +**
  1.1925 +** </dl>
  1.1926 +*/
  1.1927 +#define SQLITE_DBCONFIG_LOOKASIDE       1001  /* void* int int */
  1.1928 +#define SQLITE_DBCONFIG_ENABLE_FKEY     1002  /* int int* */
  1.1929 +#define SQLITE_DBCONFIG_ENABLE_TRIGGER  1003  /* int int* */
  1.1930 +
  1.1931 +
  1.1932 +/*
  1.1933 +** CAPI3REF: Enable Or Disable Extended Result Codes
  1.1934 +**
  1.1935 +** ^The sqlite3_extended_result_codes() routine enables or disables the
  1.1936 +** [extended result codes] feature of SQLite. ^The extended result
  1.1937 +** codes are disabled by default for historical compatibility.
  1.1938 +*/
  1.1939 +SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
  1.1940 +
  1.1941 +/*
  1.1942 +** CAPI3REF: Last Insert Rowid
  1.1943 +**
  1.1944 +** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
  1.1945 +** has a unique 64-bit signed
  1.1946 +** integer key called the [ROWID | "rowid"]. ^The rowid is always available
  1.1947 +** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
  1.1948 +** names are not also used by explicitly declared columns. ^If
  1.1949 +** the table has a column of type [INTEGER PRIMARY KEY] then that column
  1.1950 +** is another alias for the rowid.
  1.1951 +**
  1.1952 +** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the 
  1.1953 +** most recent successful [INSERT] into a rowid table or [virtual table]
  1.1954 +** on database connection D.
  1.1955 +** ^Inserts into [WITHOUT ROWID] tables are not recorded.
  1.1956 +** ^If no successful [INSERT]s into rowid tables
  1.1957 +** have ever occurred on the database connection D, 
  1.1958 +** then sqlite3_last_insert_rowid(D) returns zero.
  1.1959 +**
  1.1960 +** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
  1.1961 +** method, then this routine will return the [rowid] of the inserted
  1.1962 +** row as long as the trigger or virtual table method is running.
  1.1963 +** But once the trigger or virtual table method ends, the value returned 
  1.1964 +** by this routine reverts to what it was before the trigger or virtual
  1.1965 +** table method began.)^
  1.1966 +**
  1.1967 +** ^An [INSERT] that fails due to a constraint violation is not a
  1.1968 +** successful [INSERT] and does not change the value returned by this
  1.1969 +** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
  1.1970 +** and INSERT OR ABORT make no changes to the return value of this
  1.1971 +** routine when their insertion fails.  ^(When INSERT OR REPLACE
  1.1972 +** encounters a constraint violation, it does not fail.  The
  1.1973 +** INSERT continues to completion after deleting rows that caused
  1.1974 +** the constraint problem so INSERT OR REPLACE will always change
  1.1975 +** the return value of this interface.)^
  1.1976 +**
  1.1977 +** ^For the purposes of this routine, an [INSERT] is considered to
  1.1978 +** be successful even if it is subsequently rolled back.
  1.1979 +**
  1.1980 +** This function is accessible to SQL statements via the
  1.1981 +** [last_insert_rowid() SQL function].
  1.1982 +**
  1.1983 +** If a separate thread performs a new [INSERT] on the same
  1.1984 +** database connection while the [sqlite3_last_insert_rowid()]
  1.1985 +** function is running and thus changes the last insert [rowid],
  1.1986 +** then the value returned by [sqlite3_last_insert_rowid()] is
  1.1987 +** unpredictable and might not equal either the old or the new
  1.1988 +** last insert [rowid].
  1.1989 +*/
  1.1990 +SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
  1.1991 +
  1.1992 +/*
  1.1993 +** CAPI3REF: Count The Number Of Rows Modified
  1.1994 +**
  1.1995 +** ^This function returns the number of database rows that were changed
  1.1996 +** or inserted or deleted by the most recently completed SQL statement
  1.1997 +** on the [database connection] specified by the first parameter.
  1.1998 +** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
  1.1999 +** or [DELETE] statement are counted.  Auxiliary changes caused by
  1.2000 +** triggers or [foreign key actions] are not counted.)^ Use the
  1.2001 +** [sqlite3_total_changes()] function to find the total number of changes
  1.2002 +** including changes caused by triggers and foreign key actions.
  1.2003 +**
  1.2004 +** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
  1.2005 +** are not counted.  Only real table changes are counted.
  1.2006 +**
  1.2007 +** ^(A "row change" is a change to a single row of a single table
  1.2008 +** caused by an INSERT, DELETE, or UPDATE statement.  Rows that
  1.2009 +** are changed as side effects of [REPLACE] constraint resolution,
  1.2010 +** rollback, ABORT processing, [DROP TABLE], or by any other
  1.2011 +** mechanisms do not count as direct row changes.)^
  1.2012 +**
  1.2013 +** A "trigger context" is a scope of execution that begins and
  1.2014 +** ends with the script of a [CREATE TRIGGER | trigger]. 
  1.2015 +** Most SQL statements are
  1.2016 +** evaluated outside of any trigger.  This is the "top level"
  1.2017 +** trigger context.  If a trigger fires from the top level, a
  1.2018 +** new trigger context is entered for the duration of that one
  1.2019 +** trigger.  Subtriggers create subcontexts for their duration.
  1.2020 +**
  1.2021 +** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
  1.2022 +** not create a new trigger context.
  1.2023 +**
  1.2024 +** ^This function returns the number of direct row changes in the
  1.2025 +** most recent INSERT, UPDATE, or DELETE statement within the same
  1.2026 +** trigger context.
  1.2027 +**
  1.2028 +** ^Thus, when called from the top level, this function returns the
  1.2029 +** number of changes in the most recent INSERT, UPDATE, or DELETE
  1.2030 +** that also occurred at the top level.  ^(Within the body of a trigger,
  1.2031 +** the sqlite3_changes() interface can be called to find the number of
  1.2032 +** changes in the most recently completed INSERT, UPDATE, or DELETE
  1.2033 +** statement within the body of the same trigger.
  1.2034 +** However, the number returned does not include changes
  1.2035 +** caused by subtriggers since those have their own context.)^
  1.2036 +**
  1.2037 +** See also the [sqlite3_total_changes()] interface, the
  1.2038 +** [count_changes pragma], and the [changes() SQL function].
  1.2039 +**
  1.2040 +** If a separate thread makes changes on the same database connection
  1.2041 +** while [sqlite3_changes()] is running then the value returned
  1.2042 +** is unpredictable and not meaningful.
  1.2043 +*/
  1.2044 +SQLITE_API int sqlite3_changes(sqlite3*);
  1.2045 +
  1.2046 +/*
  1.2047 +** CAPI3REF: Total Number Of Rows Modified
  1.2048 +**
  1.2049 +** ^This function returns the number of row changes caused by [INSERT],
  1.2050 +** [UPDATE] or [DELETE] statements since the [database connection] was opened.
  1.2051 +** ^(The count returned by sqlite3_total_changes() includes all changes
  1.2052 +** from all [CREATE TRIGGER | trigger] contexts and changes made by
  1.2053 +** [foreign key actions]. However,
  1.2054 +** the count does not include changes used to implement [REPLACE] constraints,
  1.2055 +** do rollbacks or ABORT processing, or [DROP TABLE] processing.  The
  1.2056 +** count does not include rows of views that fire an [INSTEAD OF trigger],
  1.2057 +** though if the INSTEAD OF trigger makes changes of its own, those changes 
  1.2058 +** are counted.)^
  1.2059 +** ^The sqlite3_total_changes() function counts the changes as soon as
  1.2060 +** the statement that makes them is completed (when the statement handle
  1.2061 +** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
  1.2062 +**
  1.2063 +** See also the [sqlite3_changes()] interface, the
  1.2064 +** [count_changes pragma], and the [total_changes() SQL function].
  1.2065 +**
  1.2066 +** If a separate thread makes changes on the same database connection
  1.2067 +** while [sqlite3_total_changes()] is running then the value
  1.2068 +** returned is unpredictable and not meaningful.
  1.2069 +*/
  1.2070 +SQLITE_API int sqlite3_total_changes(sqlite3*);
  1.2071 +
  1.2072 +/*
  1.2073 +** CAPI3REF: Interrupt A Long-Running Query
  1.2074 +**
  1.2075 +** ^This function causes any pending database operation to abort and
  1.2076 +** return at its earliest opportunity. This routine is typically
  1.2077 +** called in response to a user action such as pressing "Cancel"
  1.2078 +** or Ctrl-C where the user wants a long query operation to halt
  1.2079 +** immediately.
  1.2080 +**
  1.2081 +** ^It is safe to call this routine from a thread different from the
  1.2082 +** thread that is currently running the database operation.  But it
  1.2083 +** is not safe to call this routine with a [database connection] that
  1.2084 +** is closed or might close before sqlite3_interrupt() returns.
  1.2085 +**
  1.2086 +** ^If an SQL operation is very nearly finished at the time when
  1.2087 +** sqlite3_interrupt() is called, then it might not have an opportunity
  1.2088 +** to be interrupted and might continue to completion.
  1.2089 +**
  1.2090 +** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
  1.2091 +** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
  1.2092 +** that is inside an explicit transaction, then the entire transaction
  1.2093 +** will be rolled back automatically.
  1.2094 +**
  1.2095 +** ^The sqlite3_interrupt(D) call is in effect until all currently running
  1.2096 +** SQL statements on [database connection] D complete.  ^Any new SQL statements
  1.2097 +** that are started after the sqlite3_interrupt() call and before the 
  1.2098 +** running statements reaches zero are interrupted as if they had been
  1.2099 +** running prior to the sqlite3_interrupt() call.  ^New SQL statements
  1.2100 +** that are started after the running statement count reaches zero are
  1.2101 +** not effected by the sqlite3_interrupt().
  1.2102 +** ^A call to sqlite3_interrupt(D) that occurs when there are no running
  1.2103 +** SQL statements is a no-op and has no effect on SQL statements
  1.2104 +** that are started after the sqlite3_interrupt() call returns.
  1.2105 +**
  1.2106 +** If the database connection closes while [sqlite3_interrupt()]
  1.2107 +** is running then bad things will likely happen.
  1.2108 +*/
  1.2109 +SQLITE_API void sqlite3_interrupt(sqlite3*);
  1.2110 +
  1.2111 +/*
  1.2112 +** CAPI3REF: Determine If An SQL Statement Is Complete
  1.2113 +**
  1.2114 +** These routines are useful during command-line input to determine if the
  1.2115 +** currently entered text seems to form a complete SQL statement or
  1.2116 +** if additional input is needed before sending the text into
  1.2117 +** SQLite for parsing.  ^These routines return 1 if the input string
  1.2118 +** appears to be a complete SQL statement.  ^A statement is judged to be
  1.2119 +** complete if it ends with a semicolon token and is not a prefix of a
  1.2120 +** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
  1.2121 +** string literals or quoted identifier names or comments are not
  1.2122 +** independent tokens (they are part of the token in which they are
  1.2123 +** embedded) and thus do not count as a statement terminator.  ^Whitespace
  1.2124 +** and comments that follow the final semicolon are ignored.
  1.2125 +**
  1.2126 +** ^These routines return 0 if the statement is incomplete.  ^If a
  1.2127 +** memory allocation fails, then SQLITE_NOMEM is returned.
  1.2128 +**
  1.2129 +** ^These routines do not parse the SQL statements thus
  1.2130 +** will not detect syntactically incorrect SQL.
  1.2131 +**
  1.2132 +** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 
  1.2133 +** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
  1.2134 +** automatically by sqlite3_complete16().  If that initialization fails,
  1.2135 +** then the return value from sqlite3_complete16() will be non-zero
  1.2136 +** regardless of whether or not the input SQL is complete.)^
  1.2137 +**
  1.2138 +** The input to [sqlite3_complete()] must be a zero-terminated
  1.2139 +** UTF-8 string.
  1.2140 +**
  1.2141 +** The input to [sqlite3_complete16()] must be a zero-terminated
  1.2142 +** UTF-16 string in native byte order.
  1.2143 +*/
  1.2144 +SQLITE_API int sqlite3_complete(const char *sql);
  1.2145 +SQLITE_API int sqlite3_complete16(const void *sql);
  1.2146 +
  1.2147 +/*
  1.2148 +** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
  1.2149 +**
  1.2150 +** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
  1.2151 +** that might be invoked with argument P whenever
  1.2152 +** an attempt is made to access a database table associated with
  1.2153 +** [database connection] D when another thread
  1.2154 +** or process has the table locked.
  1.2155 +** The sqlite3_busy_handler() interface is used to implement
  1.2156 +** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
  1.2157 +**
  1.2158 +** ^If the busy callback is NULL, then [SQLITE_BUSY]
  1.2159 +** is returned immediately upon encountering the lock.  ^If the busy callback
  1.2160 +** is not NULL, then the callback might be invoked with two arguments.
  1.2161 +**
  1.2162 +** ^The first argument to the busy handler is a copy of the void* pointer which
  1.2163 +** is the third argument to sqlite3_busy_handler().  ^The second argument to
  1.2164 +** the busy handler callback is the number of times that the busy handler has
  1.2165 +** been invoked for the same locking event.  ^If the
  1.2166 +** busy callback returns 0, then no additional attempts are made to
  1.2167 +** access the database and [SQLITE_BUSY] is returned
  1.2168 +** to the application.
  1.2169 +** ^If the callback returns non-zero, then another attempt
  1.2170 +** is made to access the database and the cycle repeats.
  1.2171 +**
  1.2172 +** The presence of a busy handler does not guarantee that it will be invoked
  1.2173 +** when there is lock contention. ^If SQLite determines that invoking the busy
  1.2174 +** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
  1.2175 +** to the application instead of invoking the 
  1.2176 +** busy handler.
  1.2177 +** Consider a scenario where one process is holding a read lock that
  1.2178 +** it is trying to promote to a reserved lock and
  1.2179 +** a second process is holding a reserved lock that it is trying
  1.2180 +** to promote to an exclusive lock.  The first process cannot proceed
  1.2181 +** because it is blocked by the second and the second process cannot
  1.2182 +** proceed because it is blocked by the first.  If both processes
  1.2183 +** invoke the busy handlers, neither will make any progress.  Therefore,
  1.2184 +** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
  1.2185 +** will induce the first process to release its read lock and allow
  1.2186 +** the second process to proceed.
  1.2187 +**
  1.2188 +** ^The default busy callback is NULL.
  1.2189 +**
  1.2190 +** ^(There can only be a single busy handler defined for each
  1.2191 +** [database connection].  Setting a new busy handler clears any
  1.2192 +** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
  1.2193 +** or evaluating [PRAGMA busy_timeout=N] will change the
  1.2194 +** busy handler and thus clear any previously set busy handler.
  1.2195 +**
  1.2196 +** The busy callback should not take any actions which modify the
  1.2197 +** database connection that invoked the busy handler.  In other words,
  1.2198 +** the busy handler is not reentrant.  Any such actions
  1.2199 +** result in undefined behavior.
  1.2200 +** 
  1.2201 +** A busy handler must not close the database connection
  1.2202 +** or [prepared statement] that invoked the busy handler.
  1.2203 +*/
  1.2204 +SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
  1.2205 +
  1.2206 +/*
  1.2207 +** CAPI3REF: Set A Busy Timeout
  1.2208 +**
  1.2209 +** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
  1.2210 +** for a specified amount of time when a table is locked.  ^The handler
  1.2211 +** will sleep multiple times until at least "ms" milliseconds of sleeping
  1.2212 +** have accumulated.  ^After at least "ms" milliseconds of sleeping,
  1.2213 +** the handler returns 0 which causes [sqlite3_step()] to return
  1.2214 +** [SQLITE_BUSY].
  1.2215 +**
  1.2216 +** ^Calling this routine with an argument less than or equal to zero
  1.2217 +** turns off all busy handlers.
  1.2218 +**
  1.2219 +** ^(There can only be a single busy handler for a particular
  1.2220 +** [database connection] any any given moment.  If another busy handler
  1.2221 +** was defined  (using [sqlite3_busy_handler()]) prior to calling
  1.2222 +** this routine, that other busy handler is cleared.)^
  1.2223 +**
  1.2224 +** See also:  [PRAGMA busy_timeout]
  1.2225 +*/
  1.2226 +SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
  1.2227 +
  1.2228 +/*
  1.2229 +** CAPI3REF: Convenience Routines For Running Queries
  1.2230 +**
  1.2231 +** This is a legacy interface that is preserved for backwards compatibility.
  1.2232 +** Use of this interface is not recommended.
  1.2233 +**
  1.2234 +** Definition: A <b>result table</b> is memory data structure created by the
  1.2235 +** [sqlite3_get_table()] interface.  A result table records the
  1.2236 +** complete query results from one or more queries.
  1.2237 +**
  1.2238 +** The table conceptually has a number of rows and columns.  But
  1.2239 +** these numbers are not part of the result table itself.  These
  1.2240 +** numbers are obtained separately.  Let N be the number of rows
  1.2241 +** and M be the number of columns.
  1.2242 +**
  1.2243 +** A result table is an array of pointers to zero-terminated UTF-8 strings.
  1.2244 +** There are (N+1)*M elements in the array.  The first M pointers point
  1.2245 +** to zero-terminated strings that  contain the names of the columns.
  1.2246 +** The remaining entries all point to query results.  NULL values result
  1.2247 +** in NULL pointers.  All other values are in their UTF-8 zero-terminated
  1.2248 +** string representation as returned by [sqlite3_column_text()].
  1.2249 +**
  1.2250 +** A result table might consist of one or more memory allocations.
  1.2251 +** It is not safe to pass a result table directly to [sqlite3_free()].
  1.2252 +** A result table should be deallocated using [sqlite3_free_table()].
  1.2253 +**
  1.2254 +** ^(As an example of the result table format, suppose a query result
  1.2255 +** is as follows:
  1.2256 +**
  1.2257 +** <blockquote><pre>
  1.2258 +**        Name        | Age
  1.2259 +**        -----------------------
  1.2260 +**        Alice       | 43
  1.2261 +**        Bob         | 28
  1.2262 +**        Cindy       | 21
  1.2263 +** </pre></blockquote>
  1.2264 +**
  1.2265 +** There are two column (M==2) and three rows (N==3).  Thus the
  1.2266 +** result table has 8 entries.  Suppose the result table is stored
  1.2267 +** in an array names azResult.  Then azResult holds this content:
  1.2268 +**
  1.2269 +** <blockquote><pre>
  1.2270 +**        azResult&#91;0] = "Name";
  1.2271 +**        azResult&#91;1] = "Age";
  1.2272 +**        azResult&#91;2] = "Alice";
  1.2273 +**        azResult&#91;3] = "43";
  1.2274 +**        azResult&#91;4] = "Bob";
  1.2275 +**        azResult&#91;5] = "28";
  1.2276 +**        azResult&#91;6] = "Cindy";
  1.2277 +**        azResult&#91;7] = "21";
  1.2278 +** </pre></blockquote>)^
  1.2279 +**
  1.2280 +** ^The sqlite3_get_table() function evaluates one or more
  1.2281 +** semicolon-separated SQL statements in the zero-terminated UTF-8
  1.2282 +** string of its 2nd parameter and returns a result table to the
  1.2283 +** pointer given in its 3rd parameter.
  1.2284 +**
  1.2285 +** After the application has finished with the result from sqlite3_get_table(),
  1.2286 +** it must pass the result table pointer to sqlite3_free_table() in order to
  1.2287 +** release the memory that was malloced.  Because of the way the
  1.2288 +** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
  1.2289 +** function must not try to call [sqlite3_free()] directly.  Only
  1.2290 +** [sqlite3_free_table()] is able to release the memory properly and safely.
  1.2291 +**
  1.2292 +** The sqlite3_get_table() interface is implemented as a wrapper around
  1.2293 +** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
  1.2294 +** to any internal data structures of SQLite.  It uses only the public
  1.2295 +** interface defined here.  As a consequence, errors that occur in the
  1.2296 +** wrapper layer outside of the internal [sqlite3_exec()] call are not
  1.2297 +** reflected in subsequent calls to [sqlite3_errcode()] or
  1.2298 +** [sqlite3_errmsg()].
  1.2299 +*/
  1.2300 +SQLITE_API int sqlite3_get_table(
  1.2301 +  sqlite3 *db,          /* An open database */
  1.2302 +  const char *zSql,     /* SQL to be evaluated */
  1.2303 +  char ***pazResult,    /* Results of the query */
  1.2304 +  int *pnRow,           /* Number of result rows written here */
  1.2305 +  int *pnColumn,        /* Number of result columns written here */
  1.2306 +  char **pzErrmsg       /* Error msg written here */
  1.2307 +);
  1.2308 +SQLITE_API void sqlite3_free_table(char **result);
  1.2309 +
  1.2310 +/*
  1.2311 +** CAPI3REF: Formatted String Printing Functions
  1.2312 +**
  1.2313 +** These routines are work-alikes of the "printf()" family of functions
  1.2314 +** from the standard C library.
  1.2315 +**
  1.2316 +** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
  1.2317 +** results into memory obtained from [sqlite3_malloc()].
  1.2318 +** The strings returned by these two routines should be
  1.2319 +** released by [sqlite3_free()].  ^Both routines return a
  1.2320 +** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
  1.2321 +** memory to hold the resulting string.
  1.2322 +**
  1.2323 +** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
  1.2324 +** the standard C library.  The result is written into the
  1.2325 +** buffer supplied as the second parameter whose size is given by
  1.2326 +** the first parameter. Note that the order of the
  1.2327 +** first two parameters is reversed from snprintf().)^  This is an
  1.2328 +** historical accident that cannot be fixed without breaking
  1.2329 +** backwards compatibility.  ^(Note also that sqlite3_snprintf()
  1.2330 +** returns a pointer to its buffer instead of the number of
  1.2331 +** characters actually written into the buffer.)^  We admit that
  1.2332 +** the number of characters written would be a more useful return
  1.2333 +** value but we cannot change the implementation of sqlite3_snprintf()
  1.2334 +** now without breaking compatibility.
  1.2335 +**
  1.2336 +** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
  1.2337 +** guarantees that the buffer is always zero-terminated.  ^The first
  1.2338 +** parameter "n" is the total size of the buffer, including space for
  1.2339 +** the zero terminator.  So the longest string that can be completely
  1.2340 +** written will be n-1 characters.
  1.2341 +**
  1.2342 +** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
  1.2343 +**
  1.2344 +** These routines all implement some additional formatting
  1.2345 +** options that are useful for constructing SQL statements.
  1.2346 +** All of the usual printf() formatting options apply.  In addition, there
  1.2347 +** is are "%q", "%Q", and "%z" options.
  1.2348 +**
  1.2349 +** ^(The %q option works like %s in that it substitutes a nul-terminated
  1.2350 +** string from the argument list.  But %q also doubles every '\'' character.
  1.2351 +** %q is designed for use inside a string literal.)^  By doubling each '\''
  1.2352 +** character it escapes that character and allows it to be inserted into
  1.2353 +** the string.
  1.2354 +**
  1.2355 +** For example, assume the string variable zText contains text as follows:
  1.2356 +**
  1.2357 +** <blockquote><pre>
  1.2358 +**  char *zText = "It's a happy day!";
  1.2359 +** </pre></blockquote>
  1.2360 +**
  1.2361 +** One can use this text in an SQL statement as follows:
  1.2362 +**
  1.2363 +** <blockquote><pre>
  1.2364 +**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
  1.2365 +**  sqlite3_exec(db, zSQL, 0, 0, 0);
  1.2366 +**  sqlite3_free(zSQL);
  1.2367 +** </pre></blockquote>
  1.2368 +**
  1.2369 +** Because the %q format string is used, the '\'' character in zText
  1.2370 +** is escaped and the SQL generated is as follows:
  1.2371 +**
  1.2372 +** <blockquote><pre>
  1.2373 +**  INSERT INTO table1 VALUES('It''s a happy day!')
  1.2374 +** </pre></blockquote>
  1.2375 +**
  1.2376 +** This is correct.  Had we used %s instead of %q, the generated SQL
  1.2377 +** would have looked like this:
  1.2378 +**
  1.2379 +** <blockquote><pre>
  1.2380 +**  INSERT INTO table1 VALUES('It's a happy day!');
  1.2381 +** </pre></blockquote>
  1.2382 +**
  1.2383 +** This second example is an SQL syntax error.  As a general rule you should
  1.2384 +** always use %q instead of %s when inserting text into a string literal.
  1.2385 +**
  1.2386 +** ^(The %Q option works like %q except it also adds single quotes around
  1.2387 +** the outside of the total string.  Additionally, if the parameter in the
  1.2388 +** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
  1.2389 +** single quotes).)^  So, for example, one could say:
  1.2390 +**
  1.2391 +** <blockquote><pre>
  1.2392 +**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
  1.2393 +**  sqlite3_exec(db, zSQL, 0, 0, 0);
  1.2394 +**  sqlite3_free(zSQL);
  1.2395 +** </pre></blockquote>
  1.2396 +**
  1.2397 +** The code above will render a correct SQL statement in the zSQL
  1.2398 +** variable even if the zText variable is a NULL pointer.
  1.2399 +**
  1.2400 +** ^(The "%z" formatting option works like "%s" but with the
  1.2401 +** addition that after the string has been read and copied into
  1.2402 +** the result, [sqlite3_free()] is called on the input string.)^
  1.2403 +*/
  1.2404 +SQLITE_API char *sqlite3_mprintf(const char*,...);
  1.2405 +SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
  1.2406 +SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
  1.2407 +SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
  1.2408 +
  1.2409 +/*
  1.2410 +** CAPI3REF: Memory Allocation Subsystem
  1.2411 +**
  1.2412 +** The SQLite core uses these three routines for all of its own
  1.2413 +** internal memory allocation needs. "Core" in the previous sentence
  1.2414 +** does not include operating-system specific VFS implementation.  The
  1.2415 +** Windows VFS uses native malloc() and free() for some operations.
  1.2416 +**
  1.2417 +** ^The sqlite3_malloc() routine returns a pointer to a block
  1.2418 +** of memory at least N bytes in length, where N is the parameter.
  1.2419 +** ^If sqlite3_malloc() is unable to obtain sufficient free
  1.2420 +** memory, it returns a NULL pointer.  ^If the parameter N to
  1.2421 +** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
  1.2422 +** a NULL pointer.
  1.2423 +**
  1.2424 +** ^Calling sqlite3_free() with a pointer previously returned
  1.2425 +** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
  1.2426 +** that it might be reused.  ^The sqlite3_free() routine is
  1.2427 +** a no-op if is called with a NULL pointer.  Passing a NULL pointer
  1.2428 +** to sqlite3_free() is harmless.  After being freed, memory
  1.2429 +** should neither be read nor written.  Even reading previously freed
  1.2430 +** memory might result in a segmentation fault or other severe error.
  1.2431 +** Memory corruption, a segmentation fault, or other severe error
  1.2432 +** might result if sqlite3_free() is called with a non-NULL pointer that
  1.2433 +** was not obtained from sqlite3_malloc() or sqlite3_realloc().
  1.2434 +**
  1.2435 +** ^(The sqlite3_realloc() interface attempts to resize a
  1.2436 +** prior memory allocation to be at least N bytes, where N is the
  1.2437 +** second parameter.  The memory allocation to be resized is the first
  1.2438 +** parameter.)^ ^ If the first parameter to sqlite3_realloc()
  1.2439 +** is a NULL pointer then its behavior is identical to calling
  1.2440 +** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
  1.2441 +** ^If the second parameter to sqlite3_realloc() is zero or
  1.2442 +** negative then the behavior is exactly the same as calling
  1.2443 +** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
  1.2444 +** ^sqlite3_realloc() returns a pointer to a memory allocation
  1.2445 +** of at least N bytes in size or NULL if sufficient memory is unavailable.
  1.2446 +** ^If M is the size of the prior allocation, then min(N,M) bytes
  1.2447 +** of the prior allocation are copied into the beginning of buffer returned
  1.2448 +** by sqlite3_realloc() and the prior allocation is freed.
  1.2449 +** ^If sqlite3_realloc() returns NULL, then the prior allocation
  1.2450 +** is not freed.
  1.2451 +**
  1.2452 +** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
  1.2453 +** is always aligned to at least an 8 byte boundary, or to a
  1.2454 +** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
  1.2455 +** option is used.
  1.2456 +**
  1.2457 +** In SQLite version 3.5.0 and 3.5.1, it was possible to define
  1.2458 +** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
  1.2459 +** implementation of these routines to be omitted.  That capability
  1.2460 +** is no longer provided.  Only built-in memory allocators can be used.
  1.2461 +**
  1.2462 +** Prior to SQLite version 3.7.10, the Windows OS interface layer called
  1.2463 +** the system malloc() and free() directly when converting
  1.2464 +** filenames between the UTF-8 encoding used by SQLite
  1.2465 +** and whatever filename encoding is used by the particular Windows
  1.2466 +** installation.  Memory allocation errors were detected, but
  1.2467 +** they were reported back as [SQLITE_CANTOPEN] or
  1.2468 +** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
  1.2469 +**
  1.2470 +** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
  1.2471 +** must be either NULL or else pointers obtained from a prior
  1.2472 +** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
  1.2473 +** not yet been released.
  1.2474 +**
  1.2475 +** The application must not read or write any part of
  1.2476 +** a block of memory after it has been released using
  1.2477 +** [sqlite3_free()] or [sqlite3_realloc()].
  1.2478 +*/
  1.2479 +SQLITE_API void *sqlite3_malloc(int);
  1.2480 +SQLITE_API void *sqlite3_realloc(void*, int);
  1.2481 +SQLITE_API void sqlite3_free(void*);
  1.2482 +
  1.2483 +/*
  1.2484 +** CAPI3REF: Memory Allocator Statistics
  1.2485 +**
  1.2486 +** SQLite provides these two interfaces for reporting on the status
  1.2487 +** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
  1.2488 +** routines, which form the built-in memory allocation subsystem.
  1.2489 +**
  1.2490 +** ^The [sqlite3_memory_used()] routine returns the number of bytes
  1.2491 +** of memory currently outstanding (malloced but not freed).
  1.2492 +** ^The [sqlite3_memory_highwater()] routine returns the maximum
  1.2493 +** value of [sqlite3_memory_used()] since the high-water mark
  1.2494 +** was last reset.  ^The values returned by [sqlite3_memory_used()] and
  1.2495 +** [sqlite3_memory_highwater()] include any overhead
  1.2496 +** added by SQLite in its implementation of [sqlite3_malloc()],
  1.2497 +** but not overhead added by the any underlying system library
  1.2498 +** routines that [sqlite3_malloc()] may call.
  1.2499 +**
  1.2500 +** ^The memory high-water mark is reset to the current value of
  1.2501 +** [sqlite3_memory_used()] if and only if the parameter to
  1.2502 +** [sqlite3_memory_highwater()] is true.  ^The value returned
  1.2503 +** by [sqlite3_memory_highwater(1)] is the high-water mark
  1.2504 +** prior to the reset.
  1.2505 +*/
  1.2506 +SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
  1.2507 +SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
  1.2508 +
  1.2509 +/*
  1.2510 +** CAPI3REF: Pseudo-Random Number Generator
  1.2511 +**
  1.2512 +** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
  1.2513 +** select random [ROWID | ROWIDs] when inserting new records into a table that
  1.2514 +** already uses the largest possible [ROWID].  The PRNG is also used for
  1.2515 +** the build-in random() and randomblob() SQL functions.  This interface allows
  1.2516 +** applications to access the same PRNG for other purposes.
  1.2517 +**
  1.2518 +** ^A call to this routine stores N bytes of randomness into buffer P.
  1.2519 +** ^If N is less than one, then P can be a NULL pointer.
  1.2520 +**
  1.2521 +** ^If this routine has not been previously called or if the previous
  1.2522 +** call had N less than one, then the PRNG is seeded using randomness
  1.2523 +** obtained from the xRandomness method of the default [sqlite3_vfs] object.
  1.2524 +** ^If the previous call to this routine had an N of 1 or more then
  1.2525 +** the pseudo-randomness is generated
  1.2526 +** internally and without recourse to the [sqlite3_vfs] xRandomness
  1.2527 +** method.
  1.2528 +*/
  1.2529 +SQLITE_API void sqlite3_randomness(int N, void *P);
  1.2530 +
  1.2531 +/*
  1.2532 +** CAPI3REF: Compile-Time Authorization Callbacks
  1.2533 +**
  1.2534 +** ^This routine registers an authorizer callback with a particular
  1.2535 +** [database connection], supplied in the first argument.
  1.2536 +** ^The authorizer callback is invoked as SQL statements are being compiled
  1.2537 +** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
  1.2538 +** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()].  ^At various
  1.2539 +** points during the compilation process, as logic is being created
  1.2540 +** to perform various actions, the authorizer callback is invoked to
  1.2541 +** see if those actions are allowed.  ^The authorizer callback should
  1.2542 +** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
  1.2543 +** specific action but allow the SQL statement to continue to be
  1.2544 +** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
  1.2545 +** rejected with an error.  ^If the authorizer callback returns
  1.2546 +** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
  1.2547 +** then the [sqlite3_prepare_v2()] or equivalent call that triggered
  1.2548 +** the authorizer will fail with an error message.
  1.2549 +**
  1.2550 +** When the callback returns [SQLITE_OK], that means the operation
  1.2551 +** requested is ok.  ^When the callback returns [SQLITE_DENY], the
  1.2552 +** [sqlite3_prepare_v2()] or equivalent call that triggered the
  1.2553 +** authorizer will fail with an error message explaining that
  1.2554 +** access is denied. 
  1.2555 +**
  1.2556 +** ^The first parameter to the authorizer callback is a copy of the third
  1.2557 +** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
  1.2558 +** to the callback is an integer [SQLITE_COPY | action code] that specifies
  1.2559 +** the particular action to be authorized. ^The third through sixth parameters
  1.2560 +** to the callback are zero-terminated strings that contain additional
  1.2561 +** details about the action to be authorized.
  1.2562 +**
  1.2563 +** ^If the action code is [SQLITE_READ]
  1.2564 +** and the callback returns [SQLITE_IGNORE] then the
  1.2565 +** [prepared statement] statement is constructed to substitute
  1.2566 +** a NULL value in place of the table column that would have
  1.2567 +** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
  1.2568 +** return can be used to deny an untrusted user access to individual
  1.2569 +** columns of a table.
  1.2570 +** ^If the action code is [SQLITE_DELETE] and the callback returns
  1.2571 +** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
  1.2572 +** [truncate optimization] is disabled and all rows are deleted individually.
  1.2573 +**
  1.2574 +** An authorizer is used when [sqlite3_prepare | preparing]
  1.2575 +** SQL statements from an untrusted source, to ensure that the SQL statements
  1.2576 +** do not try to access data they are not allowed to see, or that they do not
  1.2577 +** try to execute malicious statements that damage the database.  For
  1.2578 +** example, an application may allow a user to enter arbitrary
  1.2579 +** SQL queries for evaluation by a database.  But the application does
  1.2580 +** not want the user to be able to make arbitrary changes to the
  1.2581 +** database.  An authorizer could then be put in place while the
  1.2582 +** user-entered SQL is being [sqlite3_prepare | prepared] that
  1.2583 +** disallows everything except [SELECT] statements.
  1.2584 +**
  1.2585 +** Applications that need to process SQL from untrusted sources
  1.2586 +** might also consider lowering resource limits using [sqlite3_limit()]
  1.2587 +** and limiting database size using the [max_page_count] [PRAGMA]
  1.2588 +** in addition to using an authorizer.
  1.2589 +**
  1.2590 +** ^(Only a single authorizer can be in place on a database connection
  1.2591 +** at a time.  Each call to sqlite3_set_authorizer overrides the
  1.2592 +** previous call.)^  ^Disable the authorizer by installing a NULL callback.
  1.2593 +** The authorizer is disabled by default.
  1.2594 +**
  1.2595 +** The authorizer callback must not do anything that will modify
  1.2596 +** the database connection that invoked the authorizer callback.
  1.2597 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
  1.2598 +** database connections for the meaning of "modify" in this paragraph.
  1.2599 +**
  1.2600 +** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
  1.2601 +** statement might be re-prepared during [sqlite3_step()] due to a 
  1.2602 +** schema change.  Hence, the application should ensure that the
  1.2603 +** correct authorizer callback remains in place during the [sqlite3_step()].
  1.2604 +**
  1.2605 +** ^Note that the authorizer callback is invoked only during
  1.2606 +** [sqlite3_prepare()] or its variants.  Authorization is not
  1.2607 +** performed during statement evaluation in [sqlite3_step()], unless
  1.2608 +** as stated in the previous paragraph, sqlite3_step() invokes
  1.2609 +** sqlite3_prepare_v2() to reprepare a statement after a schema change.
  1.2610 +*/
  1.2611 +SQLITE_API int sqlite3_set_authorizer(
  1.2612 +  sqlite3*,
  1.2613 +  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
  1.2614 +  void *pUserData
  1.2615 +);
  1.2616 +
  1.2617 +/*
  1.2618 +** CAPI3REF: Authorizer Return Codes
  1.2619 +**
  1.2620 +** The [sqlite3_set_authorizer | authorizer callback function] must
  1.2621 +** return either [SQLITE_OK] or one of these two constants in order
  1.2622 +** to signal SQLite whether or not the action is permitted.  See the
  1.2623 +** [sqlite3_set_authorizer | authorizer documentation] for additional
  1.2624 +** information.
  1.2625 +**
  1.2626 +** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
  1.2627 +** returned from the [sqlite3_vtab_on_conflict()] interface.
  1.2628 +*/
  1.2629 +#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
  1.2630 +#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
  1.2631 +
  1.2632 +/*
  1.2633 +** CAPI3REF: Authorizer Action Codes
  1.2634 +**
  1.2635 +** The [sqlite3_set_authorizer()] interface registers a callback function
  1.2636 +** that is invoked to authorize certain SQL statement actions.  The
  1.2637 +** second parameter to the callback is an integer code that specifies
  1.2638 +** what action is being authorized.  These are the integer action codes that
  1.2639 +** the authorizer callback may be passed.
  1.2640 +**
  1.2641 +** These action code values signify what kind of operation is to be
  1.2642 +** authorized.  The 3rd and 4th parameters to the authorization
  1.2643 +** callback function will be parameters or NULL depending on which of these
  1.2644 +** codes is used as the second parameter.  ^(The 5th parameter to the
  1.2645 +** authorizer callback is the name of the database ("main", "temp",
  1.2646 +** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
  1.2647 +** is the name of the inner-most trigger or view that is responsible for
  1.2648 +** the access attempt or NULL if this access attempt is directly from
  1.2649 +** top-level SQL code.
  1.2650 +*/
  1.2651 +/******************************************* 3rd ************ 4th ***********/
  1.2652 +#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
  1.2653 +#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
  1.2654 +#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
  1.2655 +#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
  1.2656 +#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
  1.2657 +#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
  1.2658 +#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
  1.2659 +#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
  1.2660 +#define SQLITE_DELETE                9   /* Table Name      NULL            */
  1.2661 +#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
  1.2662 +#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
  1.2663 +#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
  1.2664 +#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
  1.2665 +#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
  1.2666 +#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
  1.2667 +#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
  1.2668 +#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
  1.2669 +#define SQLITE_INSERT               18   /* Table Name      NULL            */
  1.2670 +#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
  1.2671 +#define SQLITE_READ                 20   /* Table Name      Column Name     */
  1.2672 +#define SQLITE_SELECT               21   /* NULL            NULL            */
  1.2673 +#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
  1.2674 +#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
  1.2675 +#define SQLITE_ATTACH               24   /* Filename        NULL            */
  1.2676 +#define SQLITE_DETACH               25   /* Database Name   NULL            */
  1.2677 +#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
  1.2678 +#define SQLITE_REINDEX              27   /* Index Name      NULL            */
  1.2679 +#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
  1.2680 +#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
  1.2681 +#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
  1.2682 +#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
  1.2683 +#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
  1.2684 +#define SQLITE_COPY                  0   /* No longer used */
  1.2685 +#define SQLITE_RECURSIVE            33   /* NULL            NULL            */
  1.2686 +
  1.2687 +/*
  1.2688 +** CAPI3REF: Tracing And Profiling Functions
  1.2689 +**
  1.2690 +** These routines register callback functions that can be used for
  1.2691 +** tracing and profiling the execution of SQL statements.
  1.2692 +**
  1.2693 +** ^The callback function registered by sqlite3_trace() is invoked at
  1.2694 +** various times when an SQL statement is being run by [sqlite3_step()].
  1.2695 +** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
  1.2696 +** SQL statement text as the statement first begins executing.
  1.2697 +** ^(Additional sqlite3_trace() callbacks might occur
  1.2698 +** as each triggered subprogram is entered.  The callbacks for triggers
  1.2699 +** contain a UTF-8 SQL comment that identifies the trigger.)^
  1.2700 +**
  1.2701 +** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
  1.2702 +** the length of [bound parameter] expansion in the output of sqlite3_trace().
  1.2703 +**
  1.2704 +** ^The callback function registered by sqlite3_profile() is invoked
  1.2705 +** as each SQL statement finishes.  ^The profile callback contains
  1.2706 +** the original statement text and an estimate of wall-clock time
  1.2707 +** of how long that statement took to run.  ^The profile callback
  1.2708 +** time is in units of nanoseconds, however the current implementation
  1.2709 +** is only capable of millisecond resolution so the six least significant
  1.2710 +** digits in the time are meaningless.  Future versions of SQLite
  1.2711 +** might provide greater resolution on the profiler callback.  The
  1.2712 +** sqlite3_profile() function is considered experimental and is
  1.2713 +** subject to change in future versions of SQLite.
  1.2714 +*/
  1.2715 +SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
  1.2716 +SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
  1.2717 +   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
  1.2718 +
  1.2719 +/*
  1.2720 +** CAPI3REF: Query Progress Callbacks
  1.2721 +**
  1.2722 +** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
  1.2723 +** function X to be invoked periodically during long running calls to
  1.2724 +** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
  1.2725 +** database connection D.  An example use for this
  1.2726 +** interface is to keep a GUI updated during a large query.
  1.2727 +**
  1.2728 +** ^The parameter P is passed through as the only parameter to the 
  1.2729 +** callback function X.  ^The parameter N is the approximate number of 
  1.2730 +** [virtual machine instructions] that are evaluated between successive
  1.2731 +** invocations of the callback X.  ^If N is less than one then the progress
  1.2732 +** handler is disabled.
  1.2733 +**
  1.2734 +** ^Only a single progress handler may be defined at one time per
  1.2735 +** [database connection]; setting a new progress handler cancels the
  1.2736 +** old one.  ^Setting parameter X to NULL disables the progress handler.
  1.2737 +** ^The progress handler is also disabled by setting N to a value less
  1.2738 +** than 1.
  1.2739 +**
  1.2740 +** ^If the progress callback returns non-zero, the operation is
  1.2741 +** interrupted.  This feature can be used to implement a
  1.2742 +** "Cancel" button on a GUI progress dialog box.
  1.2743 +**
  1.2744 +** The progress handler callback must not do anything that will modify
  1.2745 +** the database connection that invoked the progress handler.
  1.2746 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
  1.2747 +** database connections for the meaning of "modify" in this paragraph.
  1.2748 +**
  1.2749 +*/
  1.2750 +SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
  1.2751 +
  1.2752 +/*
  1.2753 +** CAPI3REF: Opening A New Database Connection
  1.2754 +**
  1.2755 +** ^These routines open an SQLite database file as specified by the 
  1.2756 +** filename argument. ^The filename argument is interpreted as UTF-8 for
  1.2757 +** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
  1.2758 +** order for sqlite3_open16(). ^(A [database connection] handle is usually
  1.2759 +** returned in *ppDb, even if an error occurs.  The only exception is that
  1.2760 +** if SQLite is unable to allocate memory to hold the [sqlite3] object,
  1.2761 +** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
  1.2762 +** object.)^ ^(If the database is opened (and/or created) successfully, then
  1.2763 +** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
  1.2764 +** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
  1.2765 +** an English language description of the error following a failure of any
  1.2766 +** of the sqlite3_open() routines.
  1.2767 +**
  1.2768 +** ^The default encoding for the database will be UTF-8 if
  1.2769 +** sqlite3_open() or sqlite3_open_v2() is called and
  1.2770 +** UTF-16 in the native byte order if sqlite3_open16() is used.
  1.2771 +**
  1.2772 +** Whether or not an error occurs when it is opened, resources
  1.2773 +** associated with the [database connection] handle should be released by
  1.2774 +** passing it to [sqlite3_close()] when it is no longer required.
  1.2775 +**
  1.2776 +** The sqlite3_open_v2() interface works like sqlite3_open()
  1.2777 +** except that it accepts two additional parameters for additional control
  1.2778 +** over the new database connection.  ^(The flags parameter to
  1.2779 +** sqlite3_open_v2() can take one of
  1.2780 +** the following three values, optionally combined with the 
  1.2781 +** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
  1.2782 +** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
  1.2783 +**
  1.2784 +** <dl>
  1.2785 +** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
  1.2786 +** <dd>The database is opened in read-only mode.  If the database does not
  1.2787 +** already exist, an error is returned.</dd>)^
  1.2788 +**
  1.2789 +** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
  1.2790 +** <dd>The database is opened for reading and writing if possible, or reading
  1.2791 +** only if the file is write protected by the operating system.  In either
  1.2792 +** case the database must already exist, otherwise an error is returned.</dd>)^
  1.2793 +**
  1.2794 +** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
  1.2795 +** <dd>The database is opened for reading and writing, and is created if
  1.2796 +** it does not already exist. This is the behavior that is always used for
  1.2797 +** sqlite3_open() and sqlite3_open16().</dd>)^
  1.2798 +** </dl>
  1.2799 +**
  1.2800 +** If the 3rd parameter to sqlite3_open_v2() is not one of the
  1.2801 +** combinations shown above optionally combined with other
  1.2802 +** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
  1.2803 +** then the behavior is undefined.
  1.2804 +**
  1.2805 +** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
  1.2806 +** opens in the multi-thread [threading mode] as long as the single-thread
  1.2807 +** mode has not been set at compile-time or start-time.  ^If the
  1.2808 +** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
  1.2809 +** in the serialized [threading mode] unless single-thread was
  1.2810 +** previously selected at compile-time or start-time.
  1.2811 +** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
  1.2812 +** eligible to use [shared cache mode], regardless of whether or not shared
  1.2813 +** cache is enabled using [sqlite3_enable_shared_cache()].  ^The
  1.2814 +** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
  1.2815 +** participate in [shared cache mode] even if it is enabled.
  1.2816 +**
  1.2817 +** ^The fourth parameter to sqlite3_open_v2() is the name of the
  1.2818 +** [sqlite3_vfs] object that defines the operating system interface that
  1.2819 +** the new database connection should use.  ^If the fourth parameter is
  1.2820 +** a NULL pointer then the default [sqlite3_vfs] object is used.
  1.2821 +**
  1.2822 +** ^If the filename is ":memory:", then a private, temporary in-memory database
  1.2823 +** is created for the connection.  ^This in-memory database will vanish when
  1.2824 +** the database connection is closed.  Future versions of SQLite might
  1.2825 +** make use of additional special filenames that begin with the ":" character.
  1.2826 +** It is recommended that when a database filename actually does begin with
  1.2827 +** a ":" character you should prefix the filename with a pathname such as
  1.2828 +** "./" to avoid ambiguity.
  1.2829 +**
  1.2830 +** ^If the filename is an empty string, then a private, temporary
  1.2831 +** on-disk database will be created.  ^This private database will be
  1.2832 +** automatically deleted as soon as the database connection is closed.
  1.2833 +**
  1.2834 +** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
  1.2835 +**
  1.2836 +** ^If [URI filename] interpretation is enabled, and the filename argument
  1.2837 +** begins with "file:", then the filename is interpreted as a URI. ^URI
  1.2838 +** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
  1.2839 +** set in the fourth argument to sqlite3_open_v2(), or if it has
  1.2840 +** been enabled globally using the [SQLITE_CONFIG_URI] option with the
  1.2841 +** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
  1.2842 +** As of SQLite version 3.7.7, URI filename interpretation is turned off
  1.2843 +** by default, but future releases of SQLite might enable URI filename
  1.2844 +** interpretation by default.  See "[URI filenames]" for additional
  1.2845 +** information.
  1.2846 +**
  1.2847 +** URI filenames are parsed according to RFC 3986. ^If the URI contains an
  1.2848 +** authority, then it must be either an empty string or the string 
  1.2849 +** "localhost". ^If the authority is not an empty string or "localhost", an 
  1.2850 +** error is returned to the caller. ^The fragment component of a URI, if 
  1.2851 +** present, is ignored.
  1.2852 +**
  1.2853 +** ^SQLite uses the path component of the URI as the name of the disk file
  1.2854 +** which contains the database. ^If the path begins with a '/' character, 
  1.2855 +** then it is interpreted as an absolute path. ^If the path does not begin 
  1.2856 +** with a '/' (meaning that the authority section is omitted from the URI)
  1.2857 +** then the path is interpreted as a relative path. 
  1.2858 +** ^On windows, the first component of an absolute path 
  1.2859 +** is a drive specification (e.g. "C:").
  1.2860 +**
  1.2861 +** [[core URI query parameters]]
  1.2862 +** The query component of a URI may contain parameters that are interpreted
  1.2863 +** either by SQLite itself, or by a [VFS | custom VFS implementation].
  1.2864 +** SQLite interprets the following three query parameters:
  1.2865 +**
  1.2866 +** <ul>
  1.2867 +**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
  1.2868 +**     a VFS object that provides the operating system interface that should
  1.2869 +**     be used to access the database file on disk. ^If this option is set to
  1.2870 +**     an empty string the default VFS object is used. ^Specifying an unknown
  1.2871 +**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
  1.2872 +**     present, then the VFS specified by the option takes precedence over
  1.2873 +**     the value passed as the fourth parameter to sqlite3_open_v2().
  1.2874 +**
  1.2875 +**   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
  1.2876 +**     "rwc", or "memory". Attempting to set it to any other value is
  1.2877 +**     an error)^. 
  1.2878 +**     ^If "ro" is specified, then the database is opened for read-only 
  1.2879 +**     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 
  1.2880 +**     third argument to sqlite3_open_v2(). ^If the mode option is set to 
  1.2881 +**     "rw", then the database is opened for read-write (but not create) 
  1.2882 +**     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 
  1.2883 +**     been set. ^Value "rwc" is equivalent to setting both 
  1.2884 +**     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
  1.2885 +**     set to "memory" then a pure [in-memory database] that never reads
  1.2886 +**     or writes from disk is used. ^It is an error to specify a value for
  1.2887 +**     the mode parameter that is less restrictive than that specified by
  1.2888 +**     the flags passed in the third parameter to sqlite3_open_v2().
  1.2889 +**
  1.2890 +**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
  1.2891 +**     "private". ^Setting it to "shared" is equivalent to setting the
  1.2892 +**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
  1.2893 +**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is 
  1.2894 +**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
  1.2895 +**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
  1.2896 +**     a URI filename, its value overrides any behavior requested by setting
  1.2897 +**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
  1.2898 +**
  1.2899 +**  <li> <b>psow</b>: ^The psow parameter may be "true" (or "on" or "yes" or
  1.2900 +**     "1") or "false" (or "off" or "no" or "0") to indicate that the
  1.2901 +**     [powersafe overwrite] property does or does not apply to the
  1.2902 +**     storage media on which the database file resides.  ^The psow query
  1.2903 +**     parameter only works for the built-in unix and Windows VFSes.
  1.2904 +**
  1.2905 +**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
  1.2906 +**     which if set disables file locking in rollback journal modes.  This
  1.2907 +**     is useful for accessing a database on a filesystem that does not
  1.2908 +**     support locking.  Caution:  Database corruption might result if two
  1.2909 +**     or more processes write to the same database and any one of those
  1.2910 +**     processes uses nolock=1.
  1.2911 +**
  1.2912 +**  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
  1.2913 +**     parameter that indicates that the database file is stored on
  1.2914 +**     read-only media.  ^When immutable is set, SQLite assumes that the
  1.2915 +**     database file cannot be changed, even by a process with higher
  1.2916 +**     privilege, and so the database is opened read-only and all locking
  1.2917 +**     and change detection is disabled.  Caution: Setting the immutable
  1.2918 +**     property on a database file that does in fact change can result
  1.2919 +**     in incorrect query results and/or [SQLITE_CORRUPT] errors.
  1.2920 +**     See also: [SQLITE_IOCAP_IMMUTABLE].
  1.2921 +**       
  1.2922 +** </ul>
  1.2923 +**
  1.2924 +** ^Specifying an unknown parameter in the query component of a URI is not an
  1.2925 +** error.  Future versions of SQLite might understand additional query
  1.2926 +** parameters.  See "[query parameters with special meaning to SQLite]" for
  1.2927 +** additional information.
  1.2928 +**
  1.2929 +** [[URI filename examples]] <h3>URI filename examples</h3>
  1.2930 +**
  1.2931 +** <table border="1" align=center cellpadding=5>
  1.2932 +** <tr><th> URI filenames <th> Results
  1.2933 +** <tr><td> file:data.db <td> 
  1.2934 +**          Open the file "data.db" in the current directory.
  1.2935 +** <tr><td> file:/home/fred/data.db<br>
  1.2936 +**          file:///home/fred/data.db <br> 
  1.2937 +**          file://localhost/home/fred/data.db <br> <td> 
  1.2938 +**          Open the database file "/home/fred/data.db".
  1.2939 +** <tr><td> file://darkstar/home/fred/data.db <td> 
  1.2940 +**          An error. "darkstar" is not a recognized authority.
  1.2941 +** <tr><td style="white-space:nowrap"> 
  1.2942 +**          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
  1.2943 +**     <td> Windows only: Open the file "data.db" on fred's desktop on drive
  1.2944 +**          C:. Note that the %20 escaping in this example is not strictly 
  1.2945 +**          necessary - space characters can be used literally
  1.2946 +**          in URI filenames.
  1.2947 +** <tr><td> file:data.db?mode=ro&cache=private <td> 
  1.2948 +**          Open file "data.db" in the current directory for read-only access.
  1.2949 +**          Regardless of whether or not shared-cache mode is enabled by
  1.2950 +**          default, use a private cache.
  1.2951 +** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
  1.2952 +**          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
  1.2953 +**          that uses dot-files in place of posix advisory locking.
  1.2954 +** <tr><td> file:data.db?mode=readonly <td> 
  1.2955 +**          An error. "readonly" is not a valid option for the "mode" parameter.
  1.2956 +** </table>
  1.2957 +**
  1.2958 +** ^URI hexadecimal escape sequences (%HH) are supported within the path and
  1.2959 +** query components of a URI. A hexadecimal escape sequence consists of a
  1.2960 +** percent sign - "%" - followed by exactly two hexadecimal digits 
  1.2961 +** specifying an octet value. ^Before the path or query components of a
  1.2962 +** URI filename are interpreted, they are encoded using UTF-8 and all 
  1.2963 +** hexadecimal escape sequences replaced by a single byte containing the
  1.2964 +** corresponding octet. If this process generates an invalid UTF-8 encoding,
  1.2965 +** the results are undefined.
  1.2966 +**
  1.2967 +** <b>Note to Windows users:</b>  The encoding used for the filename argument
  1.2968 +** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
  1.2969 +** codepage is currently defined.  Filenames containing international
  1.2970 +** characters must be converted to UTF-8 prior to passing them into
  1.2971 +** sqlite3_open() or sqlite3_open_v2().
  1.2972 +**
  1.2973 +** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
  1.2974 +** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
  1.2975 +** features that require the use of temporary files may fail.
  1.2976 +**
  1.2977 +** See also: [sqlite3_temp_directory]
  1.2978 +*/
  1.2979 +SQLITE_API int sqlite3_open(
  1.2980 +  const char *filename,   /* Database filename (UTF-8) */
  1.2981 +  sqlite3 **ppDb          /* OUT: SQLite db handle */
  1.2982 +);
  1.2983 +SQLITE_API int sqlite3_open16(
  1.2984 +  const void *filename,   /* Database filename (UTF-16) */
  1.2985 +  sqlite3 **ppDb          /* OUT: SQLite db handle */
  1.2986 +);
  1.2987 +SQLITE_API int sqlite3_open_v2(
  1.2988 +  const char *filename,   /* Database filename (UTF-8) */
  1.2989 +  sqlite3 **ppDb,         /* OUT: SQLite db handle */
  1.2990 +  int flags,              /* Flags */
  1.2991 +  const char *zVfs        /* Name of VFS module to use */
  1.2992 +);
  1.2993 +
  1.2994 +/*
  1.2995 +** CAPI3REF: Obtain Values For URI Parameters
  1.2996 +**
  1.2997 +** These are utility routines, useful to VFS implementations, that check
  1.2998 +** to see if a database file was a URI that contained a specific query 
  1.2999 +** parameter, and if so obtains the value of that query parameter.
  1.3000 +**
  1.3001 +** If F is the database filename pointer passed into the xOpen() method of 
  1.3002 +** a VFS implementation when the flags parameter to xOpen() has one or 
  1.3003 +** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
  1.3004 +** P is the name of the query parameter, then
  1.3005 +** sqlite3_uri_parameter(F,P) returns the value of the P
  1.3006 +** parameter if it exists or a NULL pointer if P does not appear as a 
  1.3007 +** query parameter on F.  If P is a query parameter of F
  1.3008 +** has no explicit value, then sqlite3_uri_parameter(F,P) returns
  1.3009 +** a pointer to an empty string.
  1.3010 +**
  1.3011 +** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
  1.3012 +** parameter and returns true (1) or false (0) according to the value
  1.3013 +** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
  1.3014 +** value of query parameter P is one of "yes", "true", or "on" in any
  1.3015 +** case or if the value begins with a non-zero number.  The 
  1.3016 +** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
  1.3017 +** query parameter P is one of "no", "false", or "off" in any case or
  1.3018 +** if the value begins with a numeric zero.  If P is not a query
  1.3019 +** parameter on F or if the value of P is does not match any of the
  1.3020 +** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
  1.3021 +**
  1.3022 +** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
  1.3023 +** 64-bit signed integer and returns that integer, or D if P does not
  1.3024 +** exist.  If the value of P is something other than an integer, then
  1.3025 +** zero is returned.
  1.3026 +** 
  1.3027 +** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
  1.3028 +** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
  1.3029 +** is not a database file pathname pointer that SQLite passed into the xOpen
  1.3030 +** VFS method, then the behavior of this routine is undefined and probably
  1.3031 +** undesirable.
  1.3032 +*/
  1.3033 +SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
  1.3034 +SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
  1.3035 +SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
  1.3036 +
  1.3037 +
  1.3038 +/*
  1.3039 +** CAPI3REF: Error Codes And Messages
  1.3040 +**
  1.3041 +** ^The sqlite3_errcode() interface returns the numeric [result code] or
  1.3042 +** [extended result code] for the most recent failed sqlite3_* API call
  1.3043 +** associated with a [database connection]. If a prior API call failed
  1.3044 +** but the most recent API call succeeded, the return value from
  1.3045 +** sqlite3_errcode() is undefined.  ^The sqlite3_extended_errcode()
  1.3046 +** interface is the same except that it always returns the 
  1.3047 +** [extended result code] even when extended result codes are
  1.3048 +** disabled.
  1.3049 +**
  1.3050 +** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
  1.3051 +** text that describes the error, as either UTF-8 or UTF-16 respectively.
  1.3052 +** ^(Memory to hold the error message string is managed internally.
  1.3053 +** The application does not need to worry about freeing the result.
  1.3054 +** However, the error string might be overwritten or deallocated by
  1.3055 +** subsequent calls to other SQLite interface functions.)^
  1.3056 +**
  1.3057 +** ^The sqlite3_errstr() interface returns the English-language text
  1.3058 +** that describes the [result code], as UTF-8.
  1.3059 +** ^(Memory to hold the error message string is managed internally
  1.3060 +** and must not be freed by the application)^.
  1.3061 +**
  1.3062 +** When the serialized [threading mode] is in use, it might be the
  1.3063 +** case that a second error occurs on a separate thread in between
  1.3064 +** the time of the first error and the call to these interfaces.
  1.3065 +** When that happens, the second error will be reported since these
  1.3066 +** interfaces always report the most recent result.  To avoid
  1.3067 +** this, each thread can obtain exclusive use of the [database connection] D
  1.3068 +** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
  1.3069 +** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
  1.3070 +** all calls to the interfaces listed here are completed.
  1.3071 +**
  1.3072 +** If an interface fails with SQLITE_MISUSE, that means the interface
  1.3073 +** was invoked incorrectly by the application.  In that case, the
  1.3074 +** error code and message may or may not be set.
  1.3075 +*/
  1.3076 +SQLITE_API int sqlite3_errcode(sqlite3 *db);
  1.3077 +SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
  1.3078 +SQLITE_API const char *sqlite3_errmsg(sqlite3*);
  1.3079 +SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
  1.3080 +SQLITE_API const char *sqlite3_errstr(int);
  1.3081 +
  1.3082 +/*
  1.3083 +** CAPI3REF: SQL Statement Object
  1.3084 +** KEYWORDS: {prepared statement} {prepared statements}
  1.3085 +**
  1.3086 +** An instance of this object represents a single SQL statement.
  1.3087 +** This object is variously known as a "prepared statement" or a
  1.3088 +** "compiled SQL statement" or simply as a "statement".
  1.3089 +**
  1.3090 +** The life of a statement object goes something like this:
  1.3091 +**
  1.3092 +** <ol>
  1.3093 +** <li> Create the object using [sqlite3_prepare_v2()] or a related
  1.3094 +**      function.
  1.3095 +** <li> Bind values to [host parameters] using the sqlite3_bind_*()
  1.3096 +**      interfaces.
  1.3097 +** <li> Run the SQL by calling [sqlite3_step()] one or more times.
  1.3098 +** <li> Reset the statement using [sqlite3_reset()] then go back
  1.3099 +**      to step 2.  Do this zero or more times.
  1.3100 +** <li> Destroy the object using [sqlite3_finalize()].
  1.3101 +** </ol>
  1.3102 +**
  1.3103 +** Refer to documentation on individual methods above for additional
  1.3104 +** information.
  1.3105 +*/
  1.3106 +typedef struct sqlite3_stmt sqlite3_stmt;
  1.3107 +
  1.3108 +/*
  1.3109 +** CAPI3REF: Run-time Limits
  1.3110 +**
  1.3111 +** ^(This interface allows the size of various constructs to be limited
  1.3112 +** on a connection by connection basis.  The first parameter is the
  1.3113 +** [database connection] whose limit is to be set or queried.  The
  1.3114 +** second parameter is one of the [limit categories] that define a
  1.3115 +** class of constructs to be size limited.  The third parameter is the
  1.3116 +** new limit for that construct.)^
  1.3117 +**
  1.3118 +** ^If the new limit is a negative number, the limit is unchanged.
  1.3119 +** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 
  1.3120 +** [limits | hard upper bound]
  1.3121 +** set at compile-time by a C preprocessor macro called
  1.3122 +** [limits | SQLITE_MAX_<i>NAME</i>].
  1.3123 +** (The "_LIMIT_" in the name is changed to "_MAX_".))^
  1.3124 +** ^Attempts to increase a limit above its hard upper bound are
  1.3125 +** silently truncated to the hard upper bound.
  1.3126 +**
  1.3127 +** ^Regardless of whether or not the limit was changed, the 
  1.3128 +** [sqlite3_limit()] interface returns the prior value of the limit.
  1.3129 +** ^Hence, to find the current value of a limit without changing it,
  1.3130 +** simply invoke this interface with the third parameter set to -1.
  1.3131 +**
  1.3132 +** Run-time limits are intended for use in applications that manage
  1.3133 +** both their own internal database and also databases that are controlled
  1.3134 +** by untrusted external sources.  An example application might be a
  1.3135 +** web browser that has its own databases for storing history and
  1.3136 +** separate databases controlled by JavaScript applications downloaded
  1.3137 +** off the Internet.  The internal databases can be given the
  1.3138 +** large, default limits.  Databases managed by external sources can
  1.3139 +** be given much smaller limits designed to prevent a denial of service
  1.3140 +** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
  1.3141 +** interface to further control untrusted SQL.  The size of the database
  1.3142 +** created by an untrusted script can be contained using the
  1.3143 +** [max_page_count] [PRAGMA].
  1.3144 +**
  1.3145 +** New run-time limit categories may be added in future releases.
  1.3146 +*/
  1.3147 +SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
  1.3148 +
  1.3149 +/*
  1.3150 +** CAPI3REF: Run-Time Limit Categories
  1.3151 +** KEYWORDS: {limit category} {*limit categories}
  1.3152 +**
  1.3153 +** These constants define various performance limits
  1.3154 +** that can be lowered at run-time using [sqlite3_limit()].
  1.3155 +** The synopsis of the meanings of the various limits is shown below.
  1.3156 +** Additional information is available at [limits | Limits in SQLite].
  1.3157 +**
  1.3158 +** <dl>
  1.3159 +** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
  1.3160 +** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
  1.3161 +**
  1.3162 +** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
  1.3163 +** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
  1.3164 +**
  1.3165 +** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
  1.3166 +** <dd>The maximum number of columns in a table definition or in the
  1.3167 +** result set of a [SELECT] or the maximum number of columns in an index
  1.3168 +** or in an ORDER BY or GROUP BY clause.</dd>)^
  1.3169 +**
  1.3170 +** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
  1.3171 +** <dd>The maximum depth of the parse tree on any expression.</dd>)^
  1.3172 +**
  1.3173 +** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
  1.3174 +** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
  1.3175 +**
  1.3176 +** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
  1.3177 +** <dd>The maximum number of instructions in a virtual machine program
  1.3178 +** used to implement an SQL statement.  This limit is not currently
  1.3179 +** enforced, though that might be added in some future release of
  1.3180 +** SQLite.</dd>)^
  1.3181 +**
  1.3182 +** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
  1.3183 +** <dd>The maximum number of arguments on a function.</dd>)^
  1.3184 +**
  1.3185 +** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
  1.3186 +** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
  1.3187 +**
  1.3188 +** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
  1.3189 +** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
  1.3190 +** <dd>The maximum length of the pattern argument to the [LIKE] or
  1.3191 +** [GLOB] operators.</dd>)^
  1.3192 +**
  1.3193 +** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
  1.3194 +** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
  1.3195 +** <dd>The maximum index number of any [parameter] in an SQL statement.)^
  1.3196 +**
  1.3197 +** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
  1.3198 +** <dd>The maximum depth of recursion for triggers.</dd>)^
  1.3199 +** </dl>
  1.3200 +*/
  1.3201 +#define SQLITE_LIMIT_LENGTH                    0
  1.3202 +#define SQLITE_LIMIT_SQL_LENGTH                1
  1.3203 +#define SQLITE_LIMIT_COLUMN                    2
  1.3204 +#define SQLITE_LIMIT_EXPR_DEPTH                3
  1.3205 +#define SQLITE_LIMIT_COMPOUND_SELECT           4
  1.3206 +#define SQLITE_LIMIT_VDBE_OP                   5
  1.3207 +#define SQLITE_LIMIT_FUNCTION_ARG              6
  1.3208 +#define SQLITE_LIMIT_ATTACHED                  7
  1.3209 +#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
  1.3210 +#define SQLITE_LIMIT_VARIABLE_NUMBER           9
  1.3211 +#define SQLITE_LIMIT_TRIGGER_DEPTH            10
  1.3212 +
  1.3213 +/*
  1.3214 +** CAPI3REF: Compiling An SQL Statement
  1.3215 +** KEYWORDS: {SQL statement compiler}
  1.3216 +**
  1.3217 +** To execute an SQL query, it must first be compiled into a byte-code
  1.3218 +** program using one of these routines.
  1.3219 +**
  1.3220 +** The first argument, "db", is a [database connection] obtained from a
  1.3221 +** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
  1.3222 +** [sqlite3_open16()].  The database connection must not have been closed.
  1.3223 +**
  1.3224 +** The second argument, "zSql", is the statement to be compiled, encoded
  1.3225 +** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
  1.3226 +** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
  1.3227 +** use UTF-16.
  1.3228 +**
  1.3229 +** ^If the nByte argument is less than zero, then zSql is read up to the
  1.3230 +** first zero terminator. ^If nByte is non-negative, then it is the maximum
  1.3231 +** number of  bytes read from zSql.  ^When nByte is non-negative, the
  1.3232 +** zSql string ends at either the first '\000' or '\u0000' character or
  1.3233 +** the nByte-th byte, whichever comes first. If the caller knows
  1.3234 +** that the supplied string is nul-terminated, then there is a small
  1.3235 +** performance advantage to be gained by passing an nByte parameter that
  1.3236 +** is equal to the number of bytes in the input string <i>including</i>
  1.3237 +** the nul-terminator bytes as this saves SQLite from having to
  1.3238 +** make a copy of the input string.
  1.3239 +**
  1.3240 +** ^If pzTail is not NULL then *pzTail is made to point to the first byte
  1.3241 +** past the end of the first SQL statement in zSql.  These routines only
  1.3242 +** compile the first statement in zSql, so *pzTail is left pointing to
  1.3243 +** what remains uncompiled.
  1.3244 +**
  1.3245 +** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
  1.3246 +** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
  1.3247 +** to NULL.  ^If the input text contains no SQL (if the input is an empty
  1.3248 +** string or a comment) then *ppStmt is set to NULL.
  1.3249 +** The calling procedure is responsible for deleting the compiled
  1.3250 +** SQL statement using [sqlite3_finalize()] after it has finished with it.
  1.3251 +** ppStmt may not be NULL.
  1.3252 +**
  1.3253 +** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
  1.3254 +** otherwise an [error code] is returned.
  1.3255 +**
  1.3256 +** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
  1.3257 +** recommended for all new programs. The two older interfaces are retained
  1.3258 +** for backwards compatibility, but their use is discouraged.
  1.3259 +** ^In the "v2" interfaces, the prepared statement
  1.3260 +** that is returned (the [sqlite3_stmt] object) contains a copy of the
  1.3261 +** original SQL text. This causes the [sqlite3_step()] interface to
  1.3262 +** behave differently in three ways:
  1.3263 +**
  1.3264 +** <ol>
  1.3265 +** <li>
  1.3266 +** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
  1.3267 +** always used to do, [sqlite3_step()] will automatically recompile the SQL
  1.3268 +** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
  1.3269 +** retries will occur before sqlite3_step() gives up and returns an error.
  1.3270 +** </li>
  1.3271 +**
  1.3272 +** <li>
  1.3273 +** ^When an error occurs, [sqlite3_step()] will return one of the detailed
  1.3274 +** [error codes] or [extended error codes].  ^The legacy behavior was that
  1.3275 +** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
  1.3276 +** and the application would have to make a second call to [sqlite3_reset()]
  1.3277 +** in order to find the underlying cause of the problem. With the "v2" prepare
  1.3278 +** interfaces, the underlying reason for the error is returned immediately.
  1.3279 +** </li>
  1.3280 +**
  1.3281 +** <li>
  1.3282 +** ^If the specific value bound to [parameter | host parameter] in the 
  1.3283 +** WHERE clause might influence the choice of query plan for a statement,
  1.3284 +** then the statement will be automatically recompiled, as if there had been 
  1.3285 +** a schema change, on the first  [sqlite3_step()] call following any change
  1.3286 +** to the [sqlite3_bind_text | bindings] of that [parameter]. 
  1.3287 +** ^The specific value of WHERE-clause [parameter] might influence the 
  1.3288 +** choice of query plan if the parameter is the left-hand side of a [LIKE]
  1.3289 +** or [GLOB] operator or if the parameter is compared to an indexed column
  1.3290 +** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
  1.3291 +** </li>
  1.3292 +** </ol>
  1.3293 +*/
  1.3294 +SQLITE_API int sqlite3_prepare(
  1.3295 +  sqlite3 *db,            /* Database handle */
  1.3296 +  const char *zSql,       /* SQL statement, UTF-8 encoded */
  1.3297 +  int nByte,              /* Maximum length of zSql in bytes. */
  1.3298 +  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  1.3299 +  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
  1.3300 +);
  1.3301 +SQLITE_API int sqlite3_prepare_v2(
  1.3302 +  sqlite3 *db,            /* Database handle */
  1.3303 +  const char *zSql,       /* SQL statement, UTF-8 encoded */
  1.3304 +  int nByte,              /* Maximum length of zSql in bytes. */
  1.3305 +  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  1.3306 +  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
  1.3307 +);
  1.3308 +SQLITE_API int sqlite3_prepare16(
  1.3309 +  sqlite3 *db,            /* Database handle */
  1.3310 +  const void *zSql,       /* SQL statement, UTF-16 encoded */
  1.3311 +  int nByte,              /* Maximum length of zSql in bytes. */
  1.3312 +  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  1.3313 +  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
  1.3314 +);
  1.3315 +SQLITE_API int sqlite3_prepare16_v2(
  1.3316 +  sqlite3 *db,            /* Database handle */
  1.3317 +  const void *zSql,       /* SQL statement, UTF-16 encoded */
  1.3318 +  int nByte,              /* Maximum length of zSql in bytes. */
  1.3319 +  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  1.3320 +  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
  1.3321 +);
  1.3322 +
  1.3323 +/*
  1.3324 +** CAPI3REF: Retrieving Statement SQL
  1.3325 +**
  1.3326 +** ^This interface can be used to retrieve a saved copy of the original
  1.3327 +** SQL text used to create a [prepared statement] if that statement was
  1.3328 +** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
  1.3329 +*/
  1.3330 +SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
  1.3331 +
  1.3332 +/*
  1.3333 +** CAPI3REF: Determine If An SQL Statement Writes The Database
  1.3334 +**
  1.3335 +** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
  1.3336 +** and only if the [prepared statement] X makes no direct changes to
  1.3337 +** the content of the database file.
  1.3338 +**
  1.3339 +** Note that [application-defined SQL functions] or
  1.3340 +** [virtual tables] might change the database indirectly as a side effect.  
  1.3341 +** ^(For example, if an application defines a function "eval()" that 
  1.3342 +** calls [sqlite3_exec()], then the following SQL statement would
  1.3343 +** change the database file through side-effects:
  1.3344 +**
  1.3345 +** <blockquote><pre>
  1.3346 +**    SELECT eval('DELETE FROM t1') FROM t2;
  1.3347 +** </pre></blockquote>
  1.3348 +**
  1.3349 +** But because the [SELECT] statement does not change the database file
  1.3350 +** directly, sqlite3_stmt_readonly() would still return true.)^
  1.3351 +**
  1.3352 +** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
  1.3353 +** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
  1.3354 +** since the statements themselves do not actually modify the database but
  1.3355 +** rather they control the timing of when other statements modify the 
  1.3356 +** database.  ^The [ATTACH] and [DETACH] statements also cause
  1.3357 +** sqlite3_stmt_readonly() to return true since, while those statements
  1.3358 +** change the configuration of a database connection, they do not make 
  1.3359 +** changes to the content of the database files on disk.
  1.3360 +*/
  1.3361 +SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
  1.3362 +
  1.3363 +/*
  1.3364 +** CAPI3REF: Determine If A Prepared Statement Has Been Reset
  1.3365 +**
  1.3366 +** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
  1.3367 +** [prepared statement] S has been stepped at least once using 
  1.3368 +** [sqlite3_step(S)] but has not run to completion and/or has not 
  1.3369 +** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
  1.3370 +** interface returns false if S is a NULL pointer.  If S is not a 
  1.3371 +** NULL pointer and is not a pointer to a valid [prepared statement]
  1.3372 +** object, then the behavior is undefined and probably undesirable.
  1.3373 +**
  1.3374 +** This interface can be used in combination [sqlite3_next_stmt()]
  1.3375 +** to locate all prepared statements associated with a database 
  1.3376 +** connection that are in need of being reset.  This can be used,
  1.3377 +** for example, in diagnostic routines to search for prepared 
  1.3378 +** statements that are holding a transaction open.
  1.3379 +*/
  1.3380 +SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
  1.3381 +
  1.3382 +/*
  1.3383 +** CAPI3REF: Dynamically Typed Value Object
  1.3384 +** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
  1.3385 +**
  1.3386 +** SQLite uses the sqlite3_value object to represent all values
  1.3387 +** that can be stored in a database table. SQLite uses dynamic typing
  1.3388 +** for the values it stores.  ^Values stored in sqlite3_value objects
  1.3389 +** can be integers, floating point values, strings, BLOBs, or NULL.
  1.3390 +**
  1.3391 +** An sqlite3_value object may be either "protected" or "unprotected".
  1.3392 +** Some interfaces require a protected sqlite3_value.  Other interfaces
  1.3393 +** will accept either a protected or an unprotected sqlite3_value.
  1.3394 +** Every interface that accepts sqlite3_value arguments specifies
  1.3395 +** whether or not it requires a protected sqlite3_value.
  1.3396 +**
  1.3397 +** The terms "protected" and "unprotected" refer to whether or not
  1.3398 +** a mutex is held.  An internal mutex is held for a protected
  1.3399 +** sqlite3_value object but no mutex is held for an unprotected
  1.3400 +** sqlite3_value object.  If SQLite is compiled to be single-threaded
  1.3401 +** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
  1.3402 +** or if SQLite is run in one of reduced mutex modes 
  1.3403 +** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
  1.3404 +** then there is no distinction between protected and unprotected
  1.3405 +** sqlite3_value objects and they can be used interchangeably.  However,
  1.3406 +** for maximum code portability it is recommended that applications
  1.3407 +** still make the distinction between protected and unprotected
  1.3408 +** sqlite3_value objects even when not strictly required.
  1.3409 +**
  1.3410 +** ^The sqlite3_value objects that are passed as parameters into the
  1.3411 +** implementation of [application-defined SQL functions] are protected.
  1.3412 +** ^The sqlite3_value object returned by
  1.3413 +** [sqlite3_column_value()] is unprotected.
  1.3414 +** Unprotected sqlite3_value objects may only be used with
  1.3415 +** [sqlite3_result_value()] and [sqlite3_bind_value()].
  1.3416 +** The [sqlite3_value_blob | sqlite3_value_type()] family of
  1.3417 +** interfaces require protected sqlite3_value objects.
  1.3418 +*/
  1.3419 +typedef struct Mem sqlite3_value;
  1.3420 +
  1.3421 +/*
  1.3422 +** CAPI3REF: SQL Function Context Object
  1.3423 +**
  1.3424 +** The context in which an SQL function executes is stored in an
  1.3425 +** sqlite3_context object.  ^A pointer to an sqlite3_context object
  1.3426 +** is always first parameter to [application-defined SQL functions].
  1.3427 +** The application-defined SQL function implementation will pass this
  1.3428 +** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
  1.3429 +** [sqlite3_aggregate_context()], [sqlite3_user_data()],
  1.3430 +** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
  1.3431 +** and/or [sqlite3_set_auxdata()].
  1.3432 +*/
  1.3433 +typedef struct sqlite3_context sqlite3_context;
  1.3434 +
  1.3435 +/*
  1.3436 +** CAPI3REF: Binding Values To Prepared Statements
  1.3437 +** KEYWORDS: {host parameter} {host parameters} {host parameter name}
  1.3438 +** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
  1.3439 +**
  1.3440 +** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
  1.3441 +** literals may be replaced by a [parameter] that matches one of following
  1.3442 +** templates:
  1.3443 +**
  1.3444 +** <ul>
  1.3445 +** <li>  ?
  1.3446 +** <li>  ?NNN
  1.3447 +** <li>  :VVV
  1.3448 +** <li>  @VVV
  1.3449 +** <li>  $VVV
  1.3450 +** </ul>
  1.3451 +**
  1.3452 +** In the templates above, NNN represents an integer literal,
  1.3453 +** and VVV represents an alphanumeric identifier.)^  ^The values of these
  1.3454 +** parameters (also called "host parameter names" or "SQL parameters")
  1.3455 +** can be set using the sqlite3_bind_*() routines defined here.
  1.3456 +**
  1.3457 +** ^The first argument to the sqlite3_bind_*() routines is always
  1.3458 +** a pointer to the [sqlite3_stmt] object returned from
  1.3459 +** [sqlite3_prepare_v2()] or its variants.
  1.3460 +**
  1.3461 +** ^The second argument is the index of the SQL parameter to be set.
  1.3462 +** ^The leftmost SQL parameter has an index of 1.  ^When the same named
  1.3463 +** SQL parameter is used more than once, second and subsequent
  1.3464 +** occurrences have the same index as the first occurrence.
  1.3465 +** ^The index for named parameters can be looked up using the
  1.3466 +** [sqlite3_bind_parameter_index()] API if desired.  ^The index
  1.3467 +** for "?NNN" parameters is the value of NNN.
  1.3468 +** ^The NNN value must be between 1 and the [sqlite3_limit()]
  1.3469 +** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
  1.3470 +**
  1.3471 +** ^The third argument is the value to bind to the parameter.
  1.3472 +** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
  1.3473 +** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
  1.3474 +** is ignored and the end result is the same as sqlite3_bind_null().
  1.3475 +**
  1.3476 +** ^(In those routines that have a fourth argument, its value is the
  1.3477 +** number of bytes in the parameter.  To be clear: the value is the
  1.3478 +** number of <u>bytes</u> in the value, not the number of characters.)^
  1.3479 +** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
  1.3480 +** is negative, then the length of the string is
  1.3481 +** the number of bytes up to the first zero terminator.
  1.3482 +** If the fourth parameter to sqlite3_bind_blob() is negative, then
  1.3483 +** the behavior is undefined.
  1.3484 +** If a non-negative fourth parameter is provided to sqlite3_bind_text()
  1.3485 +** or sqlite3_bind_text16() then that parameter must be the byte offset
  1.3486 +** where the NUL terminator would occur assuming the string were NUL
  1.3487 +** terminated.  If any NUL characters occur at byte offsets less than 
  1.3488 +** the value of the fourth parameter then the resulting string value will
  1.3489 +** contain embedded NULs.  The result of expressions involving strings
  1.3490 +** with embedded NULs is undefined.
  1.3491 +**
  1.3492 +** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
  1.3493 +** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
  1.3494 +** string after SQLite has finished with it.  ^The destructor is called
  1.3495 +** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
  1.3496 +** sqlite3_bind_text(), or sqlite3_bind_text16() fails.  
  1.3497 +** ^If the fifth argument is
  1.3498 +** the special value [SQLITE_STATIC], then SQLite assumes that the
  1.3499 +** information is in static, unmanaged space and does not need to be freed.
  1.3500 +** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
  1.3501 +** SQLite makes its own private copy of the data immediately, before
  1.3502 +** the sqlite3_bind_*() routine returns.
  1.3503 +**
  1.3504 +** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
  1.3505 +** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
  1.3506 +** (just an integer to hold its size) while it is being processed.
  1.3507 +** Zeroblobs are intended to serve as placeholders for BLOBs whose
  1.3508 +** content is later written using
  1.3509 +** [sqlite3_blob_open | incremental BLOB I/O] routines.
  1.3510 +** ^A negative value for the zeroblob results in a zero-length BLOB.
  1.3511 +**
  1.3512 +** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
  1.3513 +** for the [prepared statement] or with a prepared statement for which
  1.3514 +** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
  1.3515 +** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
  1.3516 +** routine is passed a [prepared statement] that has been finalized, the
  1.3517 +** result is undefined and probably harmful.
  1.3518 +**
  1.3519 +** ^Bindings are not cleared by the [sqlite3_reset()] routine.
  1.3520 +** ^Unbound parameters are interpreted as NULL.
  1.3521 +**
  1.3522 +** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
  1.3523 +** [error code] if anything goes wrong.
  1.3524 +** ^[SQLITE_RANGE] is returned if the parameter
  1.3525 +** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
  1.3526 +**
  1.3527 +** See also: [sqlite3_bind_parameter_count()],
  1.3528 +** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
  1.3529 +*/
  1.3530 +SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
  1.3531 +SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
  1.3532 +SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
  1.3533 +SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
  1.3534 +SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
  1.3535 +SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
  1.3536 +SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
  1.3537 +SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
  1.3538 +SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
  1.3539 +
  1.3540 +/*
  1.3541 +** CAPI3REF: Number Of SQL Parameters
  1.3542 +**
  1.3543 +** ^This routine can be used to find the number of [SQL parameters]
  1.3544 +** in a [prepared statement].  SQL parameters are tokens of the
  1.3545 +** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
  1.3546 +** placeholders for values that are [sqlite3_bind_blob | bound]
  1.3547 +** to the parameters at a later time.
  1.3548 +**
  1.3549 +** ^(This routine actually returns the index of the largest (rightmost)
  1.3550 +** parameter. For all forms except ?NNN, this will correspond to the
  1.3551 +** number of unique parameters.  If parameters of the ?NNN form are used,
  1.3552 +** there may be gaps in the list.)^
  1.3553 +**
  1.3554 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
  1.3555 +** [sqlite3_bind_parameter_name()], and
  1.3556 +** [sqlite3_bind_parameter_index()].
  1.3557 +*/
  1.3558 +SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
  1.3559 +
  1.3560 +/*
  1.3561 +** CAPI3REF: Name Of A Host Parameter
  1.3562 +**
  1.3563 +** ^The sqlite3_bind_parameter_name(P,N) interface returns
  1.3564 +** the name of the N-th [SQL parameter] in the [prepared statement] P.
  1.3565 +** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
  1.3566 +** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
  1.3567 +** respectively.
  1.3568 +** In other words, the initial ":" or "$" or "@" or "?"
  1.3569 +** is included as part of the name.)^
  1.3570 +** ^Parameters of the form "?" without a following integer have no name
  1.3571 +** and are referred to as "nameless" or "anonymous parameters".
  1.3572 +**
  1.3573 +** ^The first host parameter has an index of 1, not 0.
  1.3574 +**
  1.3575 +** ^If the value N is out of range or if the N-th parameter is
  1.3576 +** nameless, then NULL is returned.  ^The returned string is
  1.3577 +** always in UTF-8 encoding even if the named parameter was
  1.3578 +** originally specified as UTF-16 in [sqlite3_prepare16()] or
  1.3579 +** [sqlite3_prepare16_v2()].
  1.3580 +**
  1.3581 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
  1.3582 +** [sqlite3_bind_parameter_count()], and
  1.3583 +** [sqlite3_bind_parameter_index()].
  1.3584 +*/
  1.3585 +SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
  1.3586 +
  1.3587 +/*
  1.3588 +** CAPI3REF: Index Of A Parameter With A Given Name
  1.3589 +**
  1.3590 +** ^Return the index of an SQL parameter given its name.  ^The
  1.3591 +** index value returned is suitable for use as the second
  1.3592 +** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
  1.3593 +** is returned if no matching parameter is found.  ^The parameter
  1.3594 +** name must be given in UTF-8 even if the original statement
  1.3595 +** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
  1.3596 +**
  1.3597 +** See also: [sqlite3_bind_blob|sqlite3_bind()],
  1.3598 +** [sqlite3_bind_parameter_count()], and
  1.3599 +** [sqlite3_bind_parameter_index()].
  1.3600 +*/
  1.3601 +SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
  1.3602 +
  1.3603 +/*
  1.3604 +** CAPI3REF: Reset All Bindings On A Prepared Statement
  1.3605 +**
  1.3606 +** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
  1.3607 +** the [sqlite3_bind_blob | bindings] on a [prepared statement].
  1.3608 +** ^Use this routine to reset all host parameters to NULL.
  1.3609 +*/
  1.3610 +SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
  1.3611 +
  1.3612 +/*
  1.3613 +** CAPI3REF: Number Of Columns In A Result Set
  1.3614 +**
  1.3615 +** ^Return the number of columns in the result set returned by the
  1.3616 +** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
  1.3617 +** statement that does not return data (for example an [UPDATE]).
  1.3618 +**
  1.3619 +** See also: [sqlite3_data_count()]
  1.3620 +*/
  1.3621 +SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
  1.3622 +
  1.3623 +/*
  1.3624 +** CAPI3REF: Column Names In A Result Set
  1.3625 +**
  1.3626 +** ^These routines return the name assigned to a particular column
  1.3627 +** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
  1.3628 +** interface returns a pointer to a zero-terminated UTF-8 string
  1.3629 +** and sqlite3_column_name16() returns a pointer to a zero-terminated
  1.3630 +** UTF-16 string.  ^The first parameter is the [prepared statement]
  1.3631 +** that implements the [SELECT] statement. ^The second parameter is the
  1.3632 +** column number.  ^The leftmost column is number 0.
  1.3633 +**
  1.3634 +** ^The returned string pointer is valid until either the [prepared statement]
  1.3635 +** is destroyed by [sqlite3_finalize()] or until the statement is automatically
  1.3636 +** reprepared by the first call to [sqlite3_step()] for a particular run
  1.3637 +** or until the next call to
  1.3638 +** sqlite3_column_name() or sqlite3_column_name16() on the same column.
  1.3639 +**
  1.3640 +** ^If sqlite3_malloc() fails during the processing of either routine
  1.3641 +** (for example during a conversion from UTF-8 to UTF-16) then a
  1.3642 +** NULL pointer is returned.
  1.3643 +**
  1.3644 +** ^The name of a result column is the value of the "AS" clause for
  1.3645 +** that column, if there is an AS clause.  If there is no AS clause
  1.3646 +** then the name of the column is unspecified and may change from
  1.3647 +** one release of SQLite to the next.
  1.3648 +*/
  1.3649 +SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
  1.3650 +SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
  1.3651 +
  1.3652 +/*
  1.3653 +** CAPI3REF: Source Of Data In A Query Result
  1.3654 +**
  1.3655 +** ^These routines provide a means to determine the database, table, and
  1.3656 +** table column that is the origin of a particular result column in
  1.3657 +** [SELECT] statement.
  1.3658 +** ^The name of the database or table or column can be returned as
  1.3659 +** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
  1.3660 +** the database name, the _table_ routines return the table name, and
  1.3661 +** the origin_ routines return the column name.
  1.3662 +** ^The returned string is valid until the [prepared statement] is destroyed
  1.3663 +** using [sqlite3_finalize()] or until the statement is automatically
  1.3664 +** reprepared by the first call to [sqlite3_step()] for a particular run
  1.3665 +** or until the same information is requested
  1.3666 +** again in a different encoding.
  1.3667 +**
  1.3668 +** ^The names returned are the original un-aliased names of the
  1.3669 +** database, table, and column.
  1.3670 +**
  1.3671 +** ^The first argument to these interfaces is a [prepared statement].
  1.3672 +** ^These functions return information about the Nth result column returned by
  1.3673 +** the statement, where N is the second function argument.
  1.3674 +** ^The left-most column is column 0 for these routines.
  1.3675 +**
  1.3676 +** ^If the Nth column returned by the statement is an expression or
  1.3677 +** subquery and is not a column value, then all of these functions return
  1.3678 +** NULL.  ^These routine might also return NULL if a memory allocation error
  1.3679 +** occurs.  ^Otherwise, they return the name of the attached database, table,
  1.3680 +** or column that query result column was extracted from.
  1.3681 +**
  1.3682 +** ^As with all other SQLite APIs, those whose names end with "16" return
  1.3683 +** UTF-16 encoded strings and the other functions return UTF-8.
  1.3684 +**
  1.3685 +** ^These APIs are only available if the library was compiled with the
  1.3686 +** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
  1.3687 +**
  1.3688 +** If two or more threads call one or more of these routines against the same
  1.3689 +** prepared statement and column at the same time then the results are
  1.3690 +** undefined.
  1.3691 +**
  1.3692 +** If two or more threads call one or more
  1.3693 +** [sqlite3_column_database_name | column metadata interfaces]
  1.3694 +** for the same [prepared statement] and result column
  1.3695 +** at the same time then the results are undefined.
  1.3696 +*/
  1.3697 +SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
  1.3698 +SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
  1.3699 +SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
  1.3700 +SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
  1.3701 +SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
  1.3702 +SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
  1.3703 +
  1.3704 +/*
  1.3705 +** CAPI3REF: Declared Datatype Of A Query Result
  1.3706 +**
  1.3707 +** ^(The first parameter is a [prepared statement].
  1.3708 +** If this statement is a [SELECT] statement and the Nth column of the
  1.3709 +** returned result set of that [SELECT] is a table column (not an
  1.3710 +** expression or subquery) then the declared type of the table
  1.3711 +** column is returned.)^  ^If the Nth column of the result set is an
  1.3712 +** expression or subquery, then a NULL pointer is returned.
  1.3713 +** ^The returned string is always UTF-8 encoded.
  1.3714 +**
  1.3715 +** ^(For example, given the database schema:
  1.3716 +**
  1.3717 +** CREATE TABLE t1(c1 VARIANT);
  1.3718 +**
  1.3719 +** and the following statement to be compiled:
  1.3720 +**
  1.3721 +** SELECT c1 + 1, c1 FROM t1;
  1.3722 +**
  1.3723 +** this routine would return the string "VARIANT" for the second result
  1.3724 +** column (i==1), and a NULL pointer for the first result column (i==0).)^
  1.3725 +**
  1.3726 +** ^SQLite uses dynamic run-time typing.  ^So just because a column
  1.3727 +** is declared to contain a particular type does not mean that the
  1.3728 +** data stored in that column is of the declared type.  SQLite is
  1.3729 +** strongly typed, but the typing is dynamic not static.  ^Type
  1.3730 +** is associated with individual values, not with the containers
  1.3731 +** used to hold those values.
  1.3732 +*/
  1.3733 +SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
  1.3734 +SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
  1.3735 +
  1.3736 +/*
  1.3737 +** CAPI3REF: Evaluate An SQL Statement
  1.3738 +**
  1.3739 +** After a [prepared statement] has been prepared using either
  1.3740 +** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
  1.3741 +** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
  1.3742 +** must be called one or more times to evaluate the statement.
  1.3743 +**
  1.3744 +** The details of the behavior of the sqlite3_step() interface depend
  1.3745 +** on whether the statement was prepared using the newer "v2" interface
  1.3746 +** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
  1.3747 +** interface [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
  1.3748 +** new "v2" interface is recommended for new applications but the legacy
  1.3749 +** interface will continue to be supported.
  1.3750 +**
  1.3751 +** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
  1.3752 +** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
  1.3753 +** ^With the "v2" interface, any of the other [result codes] or
  1.3754 +** [extended result codes] might be returned as well.
  1.3755 +**
  1.3756 +** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
  1.3757 +** database locks it needs to do its job.  ^If the statement is a [COMMIT]
  1.3758 +** or occurs outside of an explicit transaction, then you can retry the
  1.3759 +** statement.  If the statement is not a [COMMIT] and occurs within an
  1.3760 +** explicit transaction then you should rollback the transaction before
  1.3761 +** continuing.
  1.3762 +**
  1.3763 +** ^[SQLITE_DONE] means that the statement has finished executing
  1.3764 +** successfully.  sqlite3_step() should not be called again on this virtual
  1.3765 +** machine without first calling [sqlite3_reset()] to reset the virtual
  1.3766 +** machine back to its initial state.
  1.3767 +**
  1.3768 +** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
  1.3769 +** is returned each time a new row of data is ready for processing by the
  1.3770 +** caller. The values may be accessed using the [column access functions].
  1.3771 +** sqlite3_step() is called again to retrieve the next row of data.
  1.3772 +**
  1.3773 +** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
  1.3774 +** violation) has occurred.  sqlite3_step() should not be called again on
  1.3775 +** the VM. More information may be found by calling [sqlite3_errmsg()].
  1.3776 +** ^With the legacy interface, a more specific error code (for example,
  1.3777 +** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
  1.3778 +** can be obtained by calling [sqlite3_reset()] on the
  1.3779 +** [prepared statement].  ^In the "v2" interface,
  1.3780 +** the more specific error code is returned directly by sqlite3_step().
  1.3781 +**
  1.3782 +** [SQLITE_MISUSE] means that the this routine was called inappropriately.
  1.3783 +** Perhaps it was called on a [prepared statement] that has
  1.3784 +** already been [sqlite3_finalize | finalized] or on one that had
  1.3785 +** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
  1.3786 +** be the case that the same database connection is being used by two or
  1.3787 +** more threads at the same moment in time.
  1.3788 +**
  1.3789 +** For all versions of SQLite up to and including 3.6.23.1, a call to
  1.3790 +** [sqlite3_reset()] was required after sqlite3_step() returned anything
  1.3791 +** other than [SQLITE_ROW] before any subsequent invocation of
  1.3792 +** sqlite3_step().  Failure to reset the prepared statement using 
  1.3793 +** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
  1.3794 +** sqlite3_step().  But after version 3.6.23.1, sqlite3_step() began
  1.3795 +** calling [sqlite3_reset()] automatically in this circumstance rather
  1.3796 +** than returning [SQLITE_MISUSE].  This is not considered a compatibility
  1.3797 +** break because any application that ever receives an SQLITE_MISUSE error
  1.3798 +** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
  1.3799 +** can be used to restore the legacy behavior.
  1.3800 +**
  1.3801 +** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
  1.3802 +** API always returns a generic error code, [SQLITE_ERROR], following any
  1.3803 +** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
  1.3804 +** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
  1.3805 +** specific [error codes] that better describes the error.
  1.3806 +** We admit that this is a goofy design.  The problem has been fixed
  1.3807 +** with the "v2" interface.  If you prepare all of your SQL statements
  1.3808 +** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
  1.3809 +** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
  1.3810 +** then the more specific [error codes] are returned directly
  1.3811 +** by sqlite3_step().  The use of the "v2" interface is recommended.
  1.3812 +*/
  1.3813 +SQLITE_API int sqlite3_step(sqlite3_stmt*);
  1.3814 +
  1.3815 +/*
  1.3816 +** CAPI3REF: Number of columns in a result set
  1.3817 +**
  1.3818 +** ^The sqlite3_data_count(P) interface returns the number of columns in the
  1.3819 +** current row of the result set of [prepared statement] P.
  1.3820 +** ^If prepared statement P does not have results ready to return
  1.3821 +** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
  1.3822 +** interfaces) then sqlite3_data_count(P) returns 0.
  1.3823 +** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
  1.3824 +** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
  1.3825 +** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
  1.3826 +** will return non-zero if previous call to [sqlite3_step](P) returned
  1.3827 +** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
  1.3828 +** where it always returns zero since each step of that multi-step
  1.3829 +** pragma returns 0 columns of data.
  1.3830 +**
  1.3831 +** See also: [sqlite3_column_count()]
  1.3832 +*/
  1.3833 +SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
  1.3834 +
  1.3835 +/*
  1.3836 +** CAPI3REF: Fundamental Datatypes
  1.3837 +** KEYWORDS: SQLITE_TEXT
  1.3838 +**
  1.3839 +** ^(Every value in SQLite has one of five fundamental datatypes:
  1.3840 +**
  1.3841 +** <ul>
  1.3842 +** <li> 64-bit signed integer
  1.3843 +** <li> 64-bit IEEE floating point number
  1.3844 +** <li> string
  1.3845 +** <li> BLOB
  1.3846 +** <li> NULL
  1.3847 +** </ul>)^
  1.3848 +**
  1.3849 +** These constants are codes for each of those types.
  1.3850 +**
  1.3851 +** Note that the SQLITE_TEXT constant was also used in SQLite version 2
  1.3852 +** for a completely different meaning.  Software that links against both
  1.3853 +** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
  1.3854 +** SQLITE_TEXT.
  1.3855 +*/
  1.3856 +#define SQLITE_INTEGER  1
  1.3857 +#define SQLITE_FLOAT    2
  1.3858 +#define SQLITE_BLOB     4
  1.3859 +#define SQLITE_NULL     5
  1.3860 +#ifdef SQLITE_TEXT
  1.3861 +# undef SQLITE_TEXT
  1.3862 +#else
  1.3863 +# define SQLITE_TEXT     3
  1.3864 +#endif
  1.3865 +#define SQLITE3_TEXT     3
  1.3866 +
  1.3867 +/*
  1.3868 +** CAPI3REF: Result Values From A Query
  1.3869 +** KEYWORDS: {column access functions}
  1.3870 +**
  1.3871 +** These routines form the "result set" interface.
  1.3872 +**
  1.3873 +** ^These routines return information about a single column of the current
  1.3874 +** result row of a query.  ^In every case the first argument is a pointer
  1.3875 +** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
  1.3876 +** that was returned from [sqlite3_prepare_v2()] or one of its variants)
  1.3877 +** and the second argument is the index of the column for which information
  1.3878 +** should be returned. ^The leftmost column of the result set has the index 0.
  1.3879 +** ^The number of columns in the result can be determined using
  1.3880 +** [sqlite3_column_count()].
  1.3881 +**
  1.3882 +** If the SQL statement does not currently point to a valid row, or if the
  1.3883 +** column index is out of range, the result is undefined.
  1.3884 +** These routines may only be called when the most recent call to
  1.3885 +** [sqlite3_step()] has returned [SQLITE_ROW] and neither
  1.3886 +** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
  1.3887 +** If any of these routines are called after [sqlite3_reset()] or
  1.3888 +** [sqlite3_finalize()] or after [sqlite3_step()] has returned
  1.3889 +** something other than [SQLITE_ROW], the results are undefined.
  1.3890 +** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
  1.3891 +** are called from a different thread while any of these routines
  1.3892 +** are pending, then the results are undefined.
  1.3893 +**
  1.3894 +** ^The sqlite3_column_type() routine returns the
  1.3895 +** [SQLITE_INTEGER | datatype code] for the initial data type
  1.3896 +** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
  1.3897 +** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
  1.3898 +** returned by sqlite3_column_type() is only meaningful if no type
  1.3899 +** conversions have occurred as described below.  After a type conversion,
  1.3900 +** the value returned by sqlite3_column_type() is undefined.  Future
  1.3901 +** versions of SQLite may change the behavior of sqlite3_column_type()
  1.3902 +** following a type conversion.
  1.3903 +**
  1.3904 +** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
  1.3905 +** routine returns the number of bytes in that BLOB or string.
  1.3906 +** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
  1.3907 +** the string to UTF-8 and then returns the number of bytes.
  1.3908 +** ^If the result is a numeric value then sqlite3_column_bytes() uses
  1.3909 +** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
  1.3910 +** the number of bytes in that string.
  1.3911 +** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
  1.3912 +**
  1.3913 +** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
  1.3914 +** routine returns the number of bytes in that BLOB or string.
  1.3915 +** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
  1.3916 +** the string to UTF-16 and then returns the number of bytes.
  1.3917 +** ^If the result is a numeric value then sqlite3_column_bytes16() uses
  1.3918 +** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
  1.3919 +** the number of bytes in that string.
  1.3920 +** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
  1.3921 +**
  1.3922 +** ^The values returned by [sqlite3_column_bytes()] and 
  1.3923 +** [sqlite3_column_bytes16()] do not include the zero terminators at the end
  1.3924 +** of the string.  ^For clarity: the values returned by
  1.3925 +** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
  1.3926 +** bytes in the string, not the number of characters.
  1.3927 +**
  1.3928 +** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
  1.3929 +** even empty strings, are always zero-terminated.  ^The return
  1.3930 +** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
  1.3931 +**
  1.3932 +** ^The object returned by [sqlite3_column_value()] is an
  1.3933 +** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
  1.3934 +** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
  1.3935 +** If the [unprotected sqlite3_value] object returned by
  1.3936 +** [sqlite3_column_value()] is used in any other way, including calls
  1.3937 +** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
  1.3938 +** or [sqlite3_value_bytes()], then the behavior is undefined.
  1.3939 +**
  1.3940 +** These routines attempt to convert the value where appropriate.  ^For
  1.3941 +** example, if the internal representation is FLOAT and a text result
  1.3942 +** is requested, [sqlite3_snprintf()] is used internally to perform the
  1.3943 +** conversion automatically.  ^(The following table details the conversions
  1.3944 +** that are applied:
  1.3945 +**
  1.3946 +** <blockquote>
  1.3947 +** <table border="1">
  1.3948 +** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
  1.3949 +**
  1.3950 +** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
  1.3951 +** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
  1.3952 +** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
  1.3953 +** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
  1.3954 +** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
  1.3955 +** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
  1.3956 +** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
  1.3957 +** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
  1.3958 +** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
  1.3959 +** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
  1.3960 +** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
  1.3961 +** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
  1.3962 +** <tr><td>  TEXT    <td>   BLOB    <td> No change
  1.3963 +** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
  1.3964 +** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
  1.3965 +** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
  1.3966 +** </table>
  1.3967 +** </blockquote>)^
  1.3968 +**
  1.3969 +** The table above makes reference to standard C library functions atoi()
  1.3970 +** and atof().  SQLite does not really use these functions.  It has its
  1.3971 +** own equivalent internal routines.  The atoi() and atof() names are
  1.3972 +** used in the table for brevity and because they are familiar to most
  1.3973 +** C programmers.
  1.3974 +**
  1.3975 +** Note that when type conversions occur, pointers returned by prior
  1.3976 +** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
  1.3977 +** sqlite3_column_text16() may be invalidated.
  1.3978 +** Type conversions and pointer invalidations might occur
  1.3979 +** in the following cases:
  1.3980 +**
  1.3981 +** <ul>
  1.3982 +** <li> The initial content is a BLOB and sqlite3_column_text() or
  1.3983 +**      sqlite3_column_text16() is called.  A zero-terminator might
  1.3984 +**      need to be added to the string.</li>
  1.3985 +** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
  1.3986 +**      sqlite3_column_text16() is called.  The content must be converted
  1.3987 +**      to UTF-16.</li>
  1.3988 +** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
  1.3989 +**      sqlite3_column_text() is called.  The content must be converted
  1.3990 +**      to UTF-8.</li>
  1.3991 +** </ul>
  1.3992 +**
  1.3993 +** ^Conversions between UTF-16be and UTF-16le are always done in place and do
  1.3994 +** not invalidate a prior pointer, though of course the content of the buffer
  1.3995 +** that the prior pointer references will have been modified.  Other kinds
  1.3996 +** of conversion are done in place when it is possible, but sometimes they
  1.3997 +** are not possible and in those cases prior pointers are invalidated.
  1.3998 +**
  1.3999 +** The safest and easiest to remember policy is to invoke these routines
  1.4000 +** in one of the following ways:
  1.4001 +**
  1.4002 +** <ul>
  1.4003 +**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
  1.4004 +**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
  1.4005 +**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
  1.4006 +** </ul>
  1.4007 +**
  1.4008 +** In other words, you should call sqlite3_column_text(),
  1.4009 +** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
  1.4010 +** into the desired format, then invoke sqlite3_column_bytes() or
  1.4011 +** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
  1.4012 +** to sqlite3_column_text() or sqlite3_column_blob() with calls to
  1.4013 +** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
  1.4014 +** with calls to sqlite3_column_bytes().
  1.4015 +**
  1.4016 +** ^The pointers returned are valid until a type conversion occurs as
  1.4017 +** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
  1.4018 +** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
  1.4019 +** and BLOBs is freed automatically.  Do <b>not</b> pass the pointers returned
  1.4020 +** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
  1.4021 +** [sqlite3_free()].
  1.4022 +**
  1.4023 +** ^(If a memory allocation error occurs during the evaluation of any
  1.4024 +** of these routines, a default value is returned.  The default value
  1.4025 +** is either the integer 0, the floating point number 0.0, or a NULL
  1.4026 +** pointer.  Subsequent calls to [sqlite3_errcode()] will return
  1.4027 +** [SQLITE_NOMEM].)^
  1.4028 +*/
  1.4029 +SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
  1.4030 +SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
  1.4031 +SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
  1.4032 +SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
  1.4033 +SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
  1.4034 +SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
  1.4035 +SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
  1.4036 +SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
  1.4037 +SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
  1.4038 +SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
  1.4039 +
  1.4040 +/*
  1.4041 +** CAPI3REF: Destroy A Prepared Statement Object
  1.4042 +**
  1.4043 +** ^The sqlite3_finalize() function is called to delete a [prepared statement].
  1.4044 +** ^If the most recent evaluation of the statement encountered no errors
  1.4045 +** or if the statement is never been evaluated, then sqlite3_finalize() returns
  1.4046 +** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
  1.4047 +** sqlite3_finalize(S) returns the appropriate [error code] or
  1.4048 +** [extended error code].
  1.4049 +**
  1.4050 +** ^The sqlite3_finalize(S) routine can be called at any point during
  1.4051 +** the life cycle of [prepared statement] S:
  1.4052 +** before statement S is ever evaluated, after
  1.4053 +** one or more calls to [sqlite3_reset()], or after any call
  1.4054 +** to [sqlite3_step()] regardless of whether or not the statement has
  1.4055 +** completed execution.
  1.4056 +**
  1.4057 +** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
  1.4058 +**
  1.4059 +** The application must finalize every [prepared statement] in order to avoid
  1.4060 +** resource leaks.  It is a grievous error for the application to try to use
  1.4061 +** a prepared statement after it has been finalized.  Any use of a prepared
  1.4062 +** statement after it has been finalized can result in undefined and
  1.4063 +** undesirable behavior such as segfaults and heap corruption.
  1.4064 +*/
  1.4065 +SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
  1.4066 +
  1.4067 +/*
  1.4068 +** CAPI3REF: Reset A Prepared Statement Object
  1.4069 +**
  1.4070 +** The sqlite3_reset() function is called to reset a [prepared statement]
  1.4071 +** object back to its initial state, ready to be re-executed.
  1.4072 +** ^Any SQL statement variables that had values bound to them using
  1.4073 +** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
  1.4074 +** Use [sqlite3_clear_bindings()] to reset the bindings.
  1.4075 +**
  1.4076 +** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
  1.4077 +** back to the beginning of its program.
  1.4078 +**
  1.4079 +** ^If the most recent call to [sqlite3_step(S)] for the
  1.4080 +** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
  1.4081 +** or if [sqlite3_step(S)] has never before been called on S,
  1.4082 +** then [sqlite3_reset(S)] returns [SQLITE_OK].
  1.4083 +**
  1.4084 +** ^If the most recent call to [sqlite3_step(S)] for the
  1.4085 +** [prepared statement] S indicated an error, then
  1.4086 +** [sqlite3_reset(S)] returns an appropriate [error code].
  1.4087 +**
  1.4088 +** ^The [sqlite3_reset(S)] interface does not change the values
  1.4089 +** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
  1.4090 +*/
  1.4091 +SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
  1.4092 +
  1.4093 +/*
  1.4094 +** CAPI3REF: Create Or Redefine SQL Functions
  1.4095 +** KEYWORDS: {function creation routines}
  1.4096 +** KEYWORDS: {application-defined SQL function}
  1.4097 +** KEYWORDS: {application-defined SQL functions}
  1.4098 +**
  1.4099 +** ^These functions (collectively known as "function creation routines")
  1.4100 +** are used to add SQL functions or aggregates or to redefine the behavior
  1.4101 +** of existing SQL functions or aggregates.  The only differences between
  1.4102 +** these routines are the text encoding expected for
  1.4103 +** the second parameter (the name of the function being created)
  1.4104 +** and the presence or absence of a destructor callback for
  1.4105 +** the application data pointer.
  1.4106 +**
  1.4107 +** ^The first parameter is the [database connection] to which the SQL
  1.4108 +** function is to be added.  ^If an application uses more than one database
  1.4109 +** connection then application-defined SQL functions must be added
  1.4110 +** to each database connection separately.
  1.4111 +**
  1.4112 +** ^The second parameter is the name of the SQL function to be created or
  1.4113 +** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
  1.4114 +** representation, exclusive of the zero-terminator.  ^Note that the name
  1.4115 +** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.  
  1.4116 +** ^Any attempt to create a function with a longer name
  1.4117 +** will result in [SQLITE_MISUSE] being returned.
  1.4118 +**
  1.4119 +** ^The third parameter (nArg)
  1.4120 +** is the number of arguments that the SQL function or
  1.4121 +** aggregate takes. ^If this parameter is -1, then the SQL function or
  1.4122 +** aggregate may take any number of arguments between 0 and the limit
  1.4123 +** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
  1.4124 +** parameter is less than -1 or greater than 127 then the behavior is
  1.4125 +** undefined.
  1.4126 +**
  1.4127 +** ^The fourth parameter, eTextRep, specifies what
  1.4128 +** [SQLITE_UTF8 | text encoding] this SQL function prefers for
  1.4129 +** its parameters.  The application should set this parameter to
  1.4130 +** [SQLITE_UTF16LE] if the function implementation invokes 
  1.4131 +** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
  1.4132 +** implementation invokes [sqlite3_value_text16be()] on an input, or
  1.4133 +** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
  1.4134 +** otherwise.  ^The same SQL function may be registered multiple times using
  1.4135 +** different preferred text encodings, with different implementations for
  1.4136 +** each encoding.
  1.4137 +** ^When multiple implementations of the same function are available, SQLite
  1.4138 +** will pick the one that involves the least amount of data conversion.
  1.4139 +**
  1.4140 +** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
  1.4141 +** to signal that the function will always return the same result given
  1.4142 +** the same inputs within a single SQL statement.  Most SQL functions are
  1.4143 +** deterministic.  The built-in [random()] SQL function is an example of a
  1.4144 +** function that is not deterministic.  The SQLite query planner is able to
  1.4145 +** perform additional optimizations on deterministic functions, so use
  1.4146 +** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
  1.4147 +**
  1.4148 +** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
  1.4149 +** function can gain access to this pointer using [sqlite3_user_data()].)^
  1.4150 +**
  1.4151 +** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
  1.4152 +** pointers to C-language functions that implement the SQL function or
  1.4153 +** aggregate. ^A scalar SQL function requires an implementation of the xFunc
  1.4154 +** callback only; NULL pointers must be passed as the xStep and xFinal
  1.4155 +** parameters. ^An aggregate SQL function requires an implementation of xStep
  1.4156 +** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
  1.4157 +** SQL function or aggregate, pass NULL pointers for all three function
  1.4158 +** callbacks.
  1.4159 +**
  1.4160 +** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
  1.4161 +** then it is destructor for the application data pointer. 
  1.4162 +** The destructor is invoked when the function is deleted, either by being
  1.4163 +** overloaded or when the database connection closes.)^
  1.4164 +** ^The destructor is also invoked if the call to
  1.4165 +** sqlite3_create_function_v2() fails.
  1.4166 +** ^When the destructor callback of the tenth parameter is invoked, it
  1.4167 +** is passed a single argument which is a copy of the application data 
  1.4168 +** pointer which was the fifth parameter to sqlite3_create_function_v2().
  1.4169 +**
  1.4170 +** ^It is permitted to register multiple implementations of the same
  1.4171 +** functions with the same name but with either differing numbers of
  1.4172 +** arguments or differing preferred text encodings.  ^SQLite will use
  1.4173 +** the implementation that most closely matches the way in which the
  1.4174 +** SQL function is used.  ^A function implementation with a non-negative
  1.4175 +** nArg parameter is a better match than a function implementation with
  1.4176 +** a negative nArg.  ^A function where the preferred text encoding
  1.4177 +** matches the database encoding is a better
  1.4178 +** match than a function where the encoding is different.  
  1.4179 +** ^A function where the encoding difference is between UTF16le and UTF16be
  1.4180 +** is a closer match than a function where the encoding difference is
  1.4181 +** between UTF8 and UTF16.
  1.4182 +**
  1.4183 +** ^Built-in functions may be overloaded by new application-defined functions.
  1.4184 +**
  1.4185 +** ^An application-defined function is permitted to call other
  1.4186 +** SQLite interfaces.  However, such calls must not
  1.4187 +** close the database connection nor finalize or reset the prepared
  1.4188 +** statement in which the function is running.
  1.4189 +*/
  1.4190 +SQLITE_API int sqlite3_create_function(
  1.4191 +  sqlite3 *db,
  1.4192 +  const char *zFunctionName,
  1.4193 +  int nArg,
  1.4194 +  int eTextRep,
  1.4195 +  void *pApp,
  1.4196 +  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  1.4197 +  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  1.4198 +  void (*xFinal)(sqlite3_context*)
  1.4199 +);
  1.4200 +SQLITE_API int sqlite3_create_function16(
  1.4201 +  sqlite3 *db,
  1.4202 +  const void *zFunctionName,
  1.4203 +  int nArg,
  1.4204 +  int eTextRep,
  1.4205 +  void *pApp,
  1.4206 +  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  1.4207 +  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  1.4208 +  void (*xFinal)(sqlite3_context*)
  1.4209 +);
  1.4210 +SQLITE_API int sqlite3_create_function_v2(
  1.4211 +  sqlite3 *db,
  1.4212 +  const char *zFunctionName,
  1.4213 +  int nArg,
  1.4214 +  int eTextRep,
  1.4215 +  void *pApp,
  1.4216 +  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  1.4217 +  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  1.4218 +  void (*xFinal)(sqlite3_context*),
  1.4219 +  void(*xDestroy)(void*)
  1.4220 +);
  1.4221 +
  1.4222 +/*
  1.4223 +** CAPI3REF: Text Encodings
  1.4224 +**
  1.4225 +** These constant define integer codes that represent the various
  1.4226 +** text encodings supported by SQLite.
  1.4227 +*/
  1.4228 +#define SQLITE_UTF8           1
  1.4229 +#define SQLITE_UTF16LE        2
  1.4230 +#define SQLITE_UTF16BE        3
  1.4231 +#define SQLITE_UTF16          4    /* Use native byte order */
  1.4232 +#define SQLITE_ANY            5    /* Deprecated */
  1.4233 +#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
  1.4234 +
  1.4235 +/*
  1.4236 +** CAPI3REF: Function Flags
  1.4237 +**
  1.4238 +** These constants may be ORed together with the 
  1.4239 +** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
  1.4240 +** to [sqlite3_create_function()], [sqlite3_create_function16()], or
  1.4241 +** [sqlite3_create_function_v2()].
  1.4242 +*/
  1.4243 +#define SQLITE_DETERMINISTIC    0x800
  1.4244 +
  1.4245 +/*
  1.4246 +** CAPI3REF: Deprecated Functions
  1.4247 +** DEPRECATED
  1.4248 +**
  1.4249 +** These functions are [deprecated].  In order to maintain
  1.4250 +** backwards compatibility with older code, these functions continue 
  1.4251 +** to be supported.  However, new applications should avoid
  1.4252 +** the use of these functions.  To help encourage people to avoid
  1.4253 +** using these functions, we are not going to tell you what they do.
  1.4254 +*/
  1.4255 +#ifndef SQLITE_OMIT_DEPRECATED
  1.4256 +SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
  1.4257 +SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
  1.4258 +SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
  1.4259 +SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
  1.4260 +SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
  1.4261 +SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
  1.4262 +                      void*,sqlite3_int64);
  1.4263 +#endif
  1.4264 +
  1.4265 +/*
  1.4266 +** CAPI3REF: Obtaining SQL Function Parameter Values
  1.4267 +**
  1.4268 +** The C-language implementation of SQL functions and aggregates uses
  1.4269 +** this set of interface routines to access the parameter values on
  1.4270 +** the function or aggregate.
  1.4271 +**
  1.4272 +** The xFunc (for scalar functions) or xStep (for aggregates) parameters
  1.4273 +** to [sqlite3_create_function()] and [sqlite3_create_function16()]
  1.4274 +** define callbacks that implement the SQL functions and aggregates.
  1.4275 +** The 3rd parameter to these callbacks is an array of pointers to
  1.4276 +** [protected sqlite3_value] objects.  There is one [sqlite3_value] object for
  1.4277 +** each parameter to the SQL function.  These routines are used to
  1.4278 +** extract values from the [sqlite3_value] objects.
  1.4279 +**
  1.4280 +** These routines work only with [protected sqlite3_value] objects.
  1.4281 +** Any attempt to use these routines on an [unprotected sqlite3_value]
  1.4282 +** object results in undefined behavior.
  1.4283 +**
  1.4284 +** ^These routines work just like the corresponding [column access functions]
  1.4285 +** except that  these routines take a single [protected sqlite3_value] object
  1.4286 +** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
  1.4287 +**
  1.4288 +** ^The sqlite3_value_text16() interface extracts a UTF-16 string
  1.4289 +** in the native byte-order of the host machine.  ^The
  1.4290 +** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
  1.4291 +** extract UTF-16 strings as big-endian and little-endian respectively.
  1.4292 +**
  1.4293 +** ^(The sqlite3_value_numeric_type() interface attempts to apply
  1.4294 +** numeric affinity to the value.  This means that an attempt is
  1.4295 +** made to convert the value to an integer or floating point.  If
  1.4296 +** such a conversion is possible without loss of information (in other
  1.4297 +** words, if the value is a string that looks like a number)
  1.4298 +** then the conversion is performed.  Otherwise no conversion occurs.
  1.4299 +** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
  1.4300 +**
  1.4301 +** Please pay particular attention to the fact that the pointer returned
  1.4302 +** from [sqlite3_value_blob()], [sqlite3_value_text()], or
  1.4303 +** [sqlite3_value_text16()] can be invalidated by a subsequent call to
  1.4304 +** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
  1.4305 +** or [sqlite3_value_text16()].
  1.4306 +**
  1.4307 +** These routines must be called from the same thread as
  1.4308 +** the SQL function that supplied the [sqlite3_value*] parameters.
  1.4309 +*/
  1.4310 +SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
  1.4311 +SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
  1.4312 +SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
  1.4313 +SQLITE_API double sqlite3_value_double(sqlite3_value*);
  1.4314 +SQLITE_API int sqlite3_value_int(sqlite3_value*);
  1.4315 +SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
  1.4316 +SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
  1.4317 +SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
  1.4318 +SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
  1.4319 +SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
  1.4320 +SQLITE_API int sqlite3_value_type(sqlite3_value*);
  1.4321 +SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
  1.4322 +
  1.4323 +/*
  1.4324 +** CAPI3REF: Obtain Aggregate Function Context
  1.4325 +**
  1.4326 +** Implementations of aggregate SQL functions use this
  1.4327 +** routine to allocate memory for storing their state.
  1.4328 +**
  1.4329 +** ^The first time the sqlite3_aggregate_context(C,N) routine is called 
  1.4330 +** for a particular aggregate function, SQLite
  1.4331 +** allocates N of memory, zeroes out that memory, and returns a pointer
  1.4332 +** to the new memory. ^On second and subsequent calls to
  1.4333 +** sqlite3_aggregate_context() for the same aggregate function instance,
  1.4334 +** the same buffer is returned.  Sqlite3_aggregate_context() is normally
  1.4335 +** called once for each invocation of the xStep callback and then one
  1.4336 +** last time when the xFinal callback is invoked.  ^(When no rows match
  1.4337 +** an aggregate query, the xStep() callback of the aggregate function
  1.4338 +** implementation is never called and xFinal() is called exactly once.
  1.4339 +** In those cases, sqlite3_aggregate_context() might be called for the
  1.4340 +** first time from within xFinal().)^
  1.4341 +**
  1.4342 +** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 
  1.4343 +** when first called if N is less than or equal to zero or if a memory
  1.4344 +** allocate error occurs.
  1.4345 +**
  1.4346 +** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
  1.4347 +** determined by the N parameter on first successful call.  Changing the
  1.4348 +** value of N in subsequent call to sqlite3_aggregate_context() within
  1.4349 +** the same aggregate function instance will not resize the memory
  1.4350 +** allocation.)^  Within the xFinal callback, it is customary to set
  1.4351 +** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 
  1.4352 +** pointless memory allocations occur.
  1.4353 +**
  1.4354 +** ^SQLite automatically frees the memory allocated by 
  1.4355 +** sqlite3_aggregate_context() when the aggregate query concludes.
  1.4356 +**
  1.4357 +** The first parameter must be a copy of the
  1.4358 +** [sqlite3_context | SQL function context] that is the first parameter
  1.4359 +** to the xStep or xFinal callback routine that implements the aggregate
  1.4360 +** function.
  1.4361 +**
  1.4362 +** This routine must be called from the same thread in which
  1.4363 +** the aggregate SQL function is running.
  1.4364 +*/
  1.4365 +SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
  1.4366 +
  1.4367 +/*
  1.4368 +** CAPI3REF: User Data For Functions
  1.4369 +**
  1.4370 +** ^The sqlite3_user_data() interface returns a copy of
  1.4371 +** the pointer that was the pUserData parameter (the 5th parameter)
  1.4372 +** of the [sqlite3_create_function()]
  1.4373 +** and [sqlite3_create_function16()] routines that originally
  1.4374 +** registered the application defined function.
  1.4375 +**
  1.4376 +** This routine must be called from the same thread in which
  1.4377 +** the application-defined function is running.
  1.4378 +*/
  1.4379 +SQLITE_API void *sqlite3_user_data(sqlite3_context*);
  1.4380 +
  1.4381 +/*
  1.4382 +** CAPI3REF: Database Connection For Functions
  1.4383 +**
  1.4384 +** ^The sqlite3_context_db_handle() interface returns a copy of
  1.4385 +** the pointer to the [database connection] (the 1st parameter)
  1.4386 +** of the [sqlite3_create_function()]
  1.4387 +** and [sqlite3_create_function16()] routines that originally
  1.4388 +** registered the application defined function.
  1.4389 +*/
  1.4390 +SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
  1.4391 +
  1.4392 +/*
  1.4393 +** CAPI3REF: Function Auxiliary Data
  1.4394 +**
  1.4395 +** These functions may be used by (non-aggregate) SQL functions to
  1.4396 +** associate metadata with argument values. If the same value is passed to
  1.4397 +** multiple invocations of the same SQL function during query execution, under
  1.4398 +** some circumstances the associated metadata may be preserved.  An example
  1.4399 +** of where this might be useful is in a regular-expression matching
  1.4400 +** function. The compiled version of the regular expression can be stored as
  1.4401 +** metadata associated with the pattern string.  
  1.4402 +** Then as long as the pattern string remains the same,
  1.4403 +** the compiled regular expression can be reused on multiple
  1.4404 +** invocations of the same function.
  1.4405 +**
  1.4406 +** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
  1.4407 +** associated by the sqlite3_set_auxdata() function with the Nth argument
  1.4408 +** value to the application-defined function. ^If there is no metadata
  1.4409 +** associated with the function argument, this sqlite3_get_auxdata() interface
  1.4410 +** returns a NULL pointer.
  1.4411 +**
  1.4412 +** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
  1.4413 +** argument of the application-defined function.  ^Subsequent
  1.4414 +** calls to sqlite3_get_auxdata(C,N) return P from the most recent
  1.4415 +** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
  1.4416 +** NULL if the metadata has been discarded.
  1.4417 +** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
  1.4418 +** SQLite will invoke the destructor function X with parameter P exactly
  1.4419 +** once, when the metadata is discarded.
  1.4420 +** SQLite is free to discard the metadata at any time, including: <ul>
  1.4421 +** <li> when the corresponding function parameter changes, or
  1.4422 +** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
  1.4423 +**      SQL statement, or
  1.4424 +** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or
  1.4425 +** <li> during the original sqlite3_set_auxdata() call when a memory 
  1.4426 +**      allocation error occurs. </ul>)^
  1.4427 +**
  1.4428 +** Note the last bullet in particular.  The destructor X in 
  1.4429 +** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
  1.4430 +** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
  1.4431 +** should be called near the end of the function implementation and the
  1.4432 +** function implementation should not make any use of P after
  1.4433 +** sqlite3_set_auxdata() has been called.
  1.4434 +**
  1.4435 +** ^(In practice, metadata is preserved between function calls for
  1.4436 +** function parameters that are compile-time constants, including literal
  1.4437 +** values and [parameters] and expressions composed from the same.)^
  1.4438 +**
  1.4439 +** These routines must be called from the same thread in which
  1.4440 +** the SQL function is running.
  1.4441 +*/
  1.4442 +SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
  1.4443 +SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
  1.4444 +
  1.4445 +
  1.4446 +/*
  1.4447 +** CAPI3REF: Constants Defining Special Destructor Behavior
  1.4448 +**
  1.4449 +** These are special values for the destructor that is passed in as the
  1.4450 +** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
  1.4451 +** argument is SQLITE_STATIC, it means that the content pointer is constant
  1.4452 +** and will never change.  It does not need to be destroyed.  ^The
  1.4453 +** SQLITE_TRANSIENT value means that the content will likely change in
  1.4454 +** the near future and that SQLite should make its own private copy of
  1.4455 +** the content before returning.
  1.4456 +**
  1.4457 +** The typedef is necessary to work around problems in certain
  1.4458 +** C++ compilers.
  1.4459 +*/
  1.4460 +typedef void (*sqlite3_destructor_type)(void*);
  1.4461 +#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
  1.4462 +#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
  1.4463 +
  1.4464 +/*
  1.4465 +** CAPI3REF: Setting The Result Of An SQL Function
  1.4466 +**
  1.4467 +** These routines are used by the xFunc or xFinal callbacks that
  1.4468 +** implement SQL functions and aggregates.  See
  1.4469 +** [sqlite3_create_function()] and [sqlite3_create_function16()]
  1.4470 +** for additional information.
  1.4471 +**
  1.4472 +** These functions work very much like the [parameter binding] family of
  1.4473 +** functions used to bind values to host parameters in prepared statements.
  1.4474 +** Refer to the [SQL parameter] documentation for additional information.
  1.4475 +**
  1.4476 +** ^The sqlite3_result_blob() interface sets the result from
  1.4477 +** an application-defined function to be the BLOB whose content is pointed
  1.4478 +** to by the second parameter and which is N bytes long where N is the
  1.4479 +** third parameter.
  1.4480 +**
  1.4481 +** ^The sqlite3_result_zeroblob() interfaces set the result of
  1.4482 +** the application-defined function to be a BLOB containing all zero
  1.4483 +** bytes and N bytes in size, where N is the value of the 2nd parameter.
  1.4484 +**
  1.4485 +** ^The sqlite3_result_double() interface sets the result from
  1.4486 +** an application-defined function to be a floating point value specified
  1.4487 +** by its 2nd argument.
  1.4488 +**
  1.4489 +** ^The sqlite3_result_error() and sqlite3_result_error16() functions
  1.4490 +** cause the implemented SQL function to throw an exception.
  1.4491 +** ^SQLite uses the string pointed to by the
  1.4492 +** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
  1.4493 +** as the text of an error message.  ^SQLite interprets the error
  1.4494 +** message string from sqlite3_result_error() as UTF-8. ^SQLite
  1.4495 +** interprets the string from sqlite3_result_error16() as UTF-16 in native
  1.4496 +** byte order.  ^If the third parameter to sqlite3_result_error()
  1.4497 +** or sqlite3_result_error16() is negative then SQLite takes as the error
  1.4498 +** message all text up through the first zero character.
  1.4499 +** ^If the third parameter to sqlite3_result_error() or
  1.4500 +** sqlite3_result_error16() is non-negative then SQLite takes that many
  1.4501 +** bytes (not characters) from the 2nd parameter as the error message.
  1.4502 +** ^The sqlite3_result_error() and sqlite3_result_error16()
  1.4503 +** routines make a private copy of the error message text before
  1.4504 +** they return.  Hence, the calling function can deallocate or
  1.4505 +** modify the text after they return without harm.
  1.4506 +** ^The sqlite3_result_error_code() function changes the error code
  1.4507 +** returned by SQLite as a result of an error in a function.  ^By default,
  1.4508 +** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
  1.4509 +** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
  1.4510 +**
  1.4511 +** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
  1.4512 +** error indicating that a string or BLOB is too long to represent.
  1.4513 +**
  1.4514 +** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
  1.4515 +** error indicating that a memory allocation failed.
  1.4516 +**
  1.4517 +** ^The sqlite3_result_int() interface sets the return value
  1.4518 +** of the application-defined function to be the 32-bit signed integer
  1.4519 +** value given in the 2nd argument.
  1.4520 +** ^The sqlite3_result_int64() interface sets the return value
  1.4521 +** of the application-defined function to be the 64-bit signed integer
  1.4522 +** value given in the 2nd argument.
  1.4523 +**
  1.4524 +** ^The sqlite3_result_null() interface sets the return value
  1.4525 +** of the application-defined function to be NULL.
  1.4526 +**
  1.4527 +** ^The sqlite3_result_text(), sqlite3_result_text16(),
  1.4528 +** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
  1.4529 +** set the return value of the application-defined function to be
  1.4530 +** a text string which is represented as UTF-8, UTF-16 native byte order,
  1.4531 +** UTF-16 little endian, or UTF-16 big endian, respectively.
  1.4532 +** ^SQLite takes the text result from the application from
  1.4533 +** the 2nd parameter of the sqlite3_result_text* interfaces.
  1.4534 +** ^If the 3rd parameter to the sqlite3_result_text* interfaces
  1.4535 +** is negative, then SQLite takes result text from the 2nd parameter
  1.4536 +** through the first zero character.
  1.4537 +** ^If the 3rd parameter to the sqlite3_result_text* interfaces
  1.4538 +** is non-negative, then as many bytes (not characters) of the text
  1.4539 +** pointed to by the 2nd parameter are taken as the application-defined
  1.4540 +** function result.  If the 3rd parameter is non-negative, then it
  1.4541 +** must be the byte offset into the string where the NUL terminator would
  1.4542 +** appear if the string where NUL terminated.  If any NUL characters occur
  1.4543 +** in the string at a byte offset that is less than the value of the 3rd
  1.4544 +** parameter, then the resulting string will contain embedded NULs and the
  1.4545 +** result of expressions operating on strings with embedded NULs is undefined.
  1.4546 +** ^If the 4th parameter to the sqlite3_result_text* interfaces
  1.4547 +** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
  1.4548 +** function as the destructor on the text or BLOB result when it has
  1.4549 +** finished using that result.
  1.4550 +** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
  1.4551 +** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
  1.4552 +** assumes that the text or BLOB result is in constant space and does not
  1.4553 +** copy the content of the parameter nor call a destructor on the content
  1.4554 +** when it has finished using that result.
  1.4555 +** ^If the 4th parameter to the sqlite3_result_text* interfaces
  1.4556 +** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
  1.4557 +** then SQLite makes a copy of the result into space obtained from
  1.4558 +** from [sqlite3_malloc()] before it returns.
  1.4559 +**
  1.4560 +** ^The sqlite3_result_value() interface sets the result of
  1.4561 +** the application-defined function to be a copy the
  1.4562 +** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
  1.4563 +** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
  1.4564 +** so that the [sqlite3_value] specified in the parameter may change or
  1.4565 +** be deallocated after sqlite3_result_value() returns without harm.
  1.4566 +** ^A [protected sqlite3_value] object may always be used where an
  1.4567 +** [unprotected sqlite3_value] object is required, so either
  1.4568 +** kind of [sqlite3_value] object can be used with this interface.
  1.4569 +**
  1.4570 +** If these routines are called from within the different thread
  1.4571 +** than the one containing the application-defined function that received
  1.4572 +** the [sqlite3_context] pointer, the results are undefined.
  1.4573 +*/
  1.4574 +SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
  1.4575 +SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
  1.4576 +SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
  1.4577 +SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
  1.4578 +SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
  1.4579 +SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
  1.4580 +SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
  1.4581 +SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
  1.4582 +SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
  1.4583 +SQLITE_API void sqlite3_result_null(sqlite3_context*);
  1.4584 +SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
  1.4585 +SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
  1.4586 +SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
  1.4587 +SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
  1.4588 +SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
  1.4589 +SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
  1.4590 +
  1.4591 +/*
  1.4592 +** CAPI3REF: Define New Collating Sequences
  1.4593 +**
  1.4594 +** ^These functions add, remove, or modify a [collation] associated
  1.4595 +** with the [database connection] specified as the first argument.
  1.4596 +**
  1.4597 +** ^The name of the collation is a UTF-8 string
  1.4598 +** for sqlite3_create_collation() and sqlite3_create_collation_v2()
  1.4599 +** and a UTF-16 string in native byte order for sqlite3_create_collation16().
  1.4600 +** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
  1.4601 +** considered to be the same name.
  1.4602 +**
  1.4603 +** ^(The third argument (eTextRep) must be one of the constants:
  1.4604 +** <ul>
  1.4605 +** <li> [SQLITE_UTF8],
  1.4606 +** <li> [SQLITE_UTF16LE],
  1.4607 +** <li> [SQLITE_UTF16BE],
  1.4608 +** <li> [SQLITE_UTF16], or
  1.4609 +** <li> [SQLITE_UTF16_ALIGNED].
  1.4610 +** </ul>)^
  1.4611 +** ^The eTextRep argument determines the encoding of strings passed
  1.4612 +** to the collating function callback, xCallback.
  1.4613 +** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
  1.4614 +** force strings to be UTF16 with native byte order.
  1.4615 +** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
  1.4616 +** on an even byte address.
  1.4617 +**
  1.4618 +** ^The fourth argument, pArg, is an application data pointer that is passed
  1.4619 +** through as the first argument to the collating function callback.
  1.4620 +**
  1.4621 +** ^The fifth argument, xCallback, is a pointer to the collating function.
  1.4622 +** ^Multiple collating functions can be registered using the same name but
  1.4623 +** with different eTextRep parameters and SQLite will use whichever
  1.4624 +** function requires the least amount of data transformation.
  1.4625 +** ^If the xCallback argument is NULL then the collating function is
  1.4626 +** deleted.  ^When all collating functions having the same name are deleted,
  1.4627 +** that collation is no longer usable.
  1.4628 +**
  1.4629 +** ^The collating function callback is invoked with a copy of the pArg 
  1.4630 +** application data pointer and with two strings in the encoding specified
  1.4631 +** by the eTextRep argument.  The collating function must return an
  1.4632 +** integer that is negative, zero, or positive
  1.4633 +** if the first string is less than, equal to, or greater than the second,
  1.4634 +** respectively.  A collating function must always return the same answer
  1.4635 +** given the same inputs.  If two or more collating functions are registered
  1.4636 +** to the same collation name (using different eTextRep values) then all
  1.4637 +** must give an equivalent answer when invoked with equivalent strings.
  1.4638 +** The collating function must obey the following properties for all
  1.4639 +** strings A, B, and C:
  1.4640 +**
  1.4641 +** <ol>
  1.4642 +** <li> If A==B then B==A.
  1.4643 +** <li> If A==B and B==C then A==C.
  1.4644 +** <li> If A&lt;B THEN B&gt;A.
  1.4645 +** <li> If A&lt;B and B&lt;C then A&lt;C.
  1.4646 +** </ol>
  1.4647 +**
  1.4648 +** If a collating function fails any of the above constraints and that
  1.4649 +** collating function is  registered and used, then the behavior of SQLite
  1.4650 +** is undefined.
  1.4651 +**
  1.4652 +** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
  1.4653 +** with the addition that the xDestroy callback is invoked on pArg when
  1.4654 +** the collating function is deleted.
  1.4655 +** ^Collating functions are deleted when they are overridden by later
  1.4656 +** calls to the collation creation functions or when the
  1.4657 +** [database connection] is closed using [sqlite3_close()].
  1.4658 +**
  1.4659 +** ^The xDestroy callback is <u>not</u> called if the 
  1.4660 +** sqlite3_create_collation_v2() function fails.  Applications that invoke
  1.4661 +** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 
  1.4662 +** check the return code and dispose of the application data pointer
  1.4663 +** themselves rather than expecting SQLite to deal with it for them.
  1.4664 +** This is different from every other SQLite interface.  The inconsistency 
  1.4665 +** is unfortunate but cannot be changed without breaking backwards 
  1.4666 +** compatibility.
  1.4667 +**
  1.4668 +** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
  1.4669 +*/
  1.4670 +SQLITE_API int sqlite3_create_collation(
  1.4671 +  sqlite3*, 
  1.4672 +  const char *zName, 
  1.4673 +  int eTextRep, 
  1.4674 +  void *pArg,
  1.4675 +  int(*xCompare)(void*,int,const void*,int,const void*)
  1.4676 +);
  1.4677 +SQLITE_API int sqlite3_create_collation_v2(
  1.4678 +  sqlite3*, 
  1.4679 +  const char *zName, 
  1.4680 +  int eTextRep, 
  1.4681 +  void *pArg,
  1.4682 +  int(*xCompare)(void*,int,const void*,int,const void*),
  1.4683 +  void(*xDestroy)(void*)
  1.4684 +);
  1.4685 +SQLITE_API int sqlite3_create_collation16(
  1.4686 +  sqlite3*, 
  1.4687 +  const void *zName,
  1.4688 +  int eTextRep, 
  1.4689 +  void *pArg,
  1.4690 +  int(*xCompare)(void*,int,const void*,int,const void*)
  1.4691 +);
  1.4692 +
  1.4693 +/*
  1.4694 +** CAPI3REF: Collation Needed Callbacks
  1.4695 +**
  1.4696 +** ^To avoid having to register all collation sequences before a database
  1.4697 +** can be used, a single callback function may be registered with the
  1.4698 +** [database connection] to be invoked whenever an undefined collation
  1.4699 +** sequence is required.
  1.4700 +**
  1.4701 +** ^If the function is registered using the sqlite3_collation_needed() API,
  1.4702 +** then it is passed the names of undefined collation sequences as strings
  1.4703 +** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
  1.4704 +** the names are passed as UTF-16 in machine native byte order.
  1.4705 +** ^A call to either function replaces the existing collation-needed callback.
  1.4706 +**
  1.4707 +** ^(When the callback is invoked, the first argument passed is a copy
  1.4708 +** of the second argument to sqlite3_collation_needed() or
  1.4709 +** sqlite3_collation_needed16().  The second argument is the database
  1.4710 +** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
  1.4711 +** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
  1.4712 +** sequence function required.  The fourth parameter is the name of the
  1.4713 +** required collation sequence.)^
  1.4714 +**
  1.4715 +** The callback function should register the desired collation using
  1.4716 +** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
  1.4717 +** [sqlite3_create_collation_v2()].
  1.4718 +*/
  1.4719 +SQLITE_API int sqlite3_collation_needed(
  1.4720 +  sqlite3*, 
  1.4721 +  void*, 
  1.4722 +  void(*)(void*,sqlite3*,int eTextRep,const char*)
  1.4723 +);
  1.4724 +SQLITE_API int sqlite3_collation_needed16(
  1.4725 +  sqlite3*, 
  1.4726 +  void*,
  1.4727 +  void(*)(void*,sqlite3*,int eTextRep,const void*)
  1.4728 +);
  1.4729 +
  1.4730 +#ifdef SQLITE_HAS_CODEC
  1.4731 +/*
  1.4732 +** Specify the key for an encrypted database.  This routine should be
  1.4733 +** called right after sqlite3_open().
  1.4734 +**
  1.4735 +** The code to implement this API is not available in the public release
  1.4736 +** of SQLite.
  1.4737 +*/
  1.4738 +SQLITE_API int sqlite3_key(
  1.4739 +  sqlite3 *db,                   /* Database to be rekeyed */
  1.4740 +  const void *pKey, int nKey     /* The key */
  1.4741 +);
  1.4742 +SQLITE_API int sqlite3_key_v2(
  1.4743 +  sqlite3 *db,                   /* Database to be rekeyed */
  1.4744 +  const char *zDbName,           /* Name of the database */
  1.4745 +  const void *pKey, int nKey     /* The key */
  1.4746 +);
  1.4747 +
  1.4748 +/*
  1.4749 +** Change the key on an open database.  If the current database is not
  1.4750 +** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
  1.4751 +** database is decrypted.
  1.4752 +**
  1.4753 +** The code to implement this API is not available in the public release
  1.4754 +** of SQLite.
  1.4755 +*/
  1.4756 +SQLITE_API int sqlite3_rekey(
  1.4757 +  sqlite3 *db,                   /* Database to be rekeyed */
  1.4758 +  const void *pKey, int nKey     /* The new key */
  1.4759 +);
  1.4760 +SQLITE_API int sqlite3_rekey_v2(
  1.4761 +  sqlite3 *db,                   /* Database to be rekeyed */
  1.4762 +  const char *zDbName,           /* Name of the database */
  1.4763 +  const void *pKey, int nKey     /* The new key */
  1.4764 +);
  1.4765 +
  1.4766 +/*
  1.4767 +** Specify the activation key for a SEE database.  Unless 
  1.4768 +** activated, none of the SEE routines will work.
  1.4769 +*/
  1.4770 +SQLITE_API void sqlite3_activate_see(
  1.4771 +  const char *zPassPhrase        /* Activation phrase */
  1.4772 +);
  1.4773 +#endif
  1.4774 +
  1.4775 +#ifdef SQLITE_ENABLE_CEROD
  1.4776 +/*
  1.4777 +** Specify the activation key for a CEROD database.  Unless 
  1.4778 +** activated, none of the CEROD routines will work.
  1.4779 +*/
  1.4780 +SQLITE_API void sqlite3_activate_cerod(
  1.4781 +  const char *zPassPhrase        /* Activation phrase */
  1.4782 +);
  1.4783 +#endif
  1.4784 +
  1.4785 +/*
  1.4786 +** CAPI3REF: Suspend Execution For A Short Time
  1.4787 +**
  1.4788 +** The sqlite3_sleep() function causes the current thread to suspend execution
  1.4789 +** for at least a number of milliseconds specified in its parameter.
  1.4790 +**
  1.4791 +** If the operating system does not support sleep requests with
  1.4792 +** millisecond time resolution, then the time will be rounded up to
  1.4793 +** the nearest second. The number of milliseconds of sleep actually
  1.4794 +** requested from the operating system is returned.
  1.4795 +**
  1.4796 +** ^SQLite implements this interface by calling the xSleep()
  1.4797 +** method of the default [sqlite3_vfs] object.  If the xSleep() method
  1.4798 +** of the default VFS is not implemented correctly, or not implemented at
  1.4799 +** all, then the behavior of sqlite3_sleep() may deviate from the description
  1.4800 +** in the previous paragraphs.
  1.4801 +*/
  1.4802 +SQLITE_API int sqlite3_sleep(int);
  1.4803 +
  1.4804 +/*
  1.4805 +** CAPI3REF: Name Of The Folder Holding Temporary Files
  1.4806 +**
  1.4807 +** ^(If this global variable is made to point to a string which is
  1.4808 +** the name of a folder (a.k.a. directory), then all temporary files
  1.4809 +** created by SQLite when using a built-in [sqlite3_vfs | VFS]
  1.4810 +** will be placed in that directory.)^  ^If this variable
  1.4811 +** is a NULL pointer, then SQLite performs a search for an appropriate
  1.4812 +** temporary file directory.
  1.4813 +**
  1.4814 +** Applications are strongly discouraged from using this global variable.
  1.4815 +** It is required to set a temporary folder on Windows Runtime (WinRT).
  1.4816 +** But for all other platforms, it is highly recommended that applications
  1.4817 +** neither read nor write this variable.  This global variable is a relic
  1.4818 +** that exists for backwards compatibility of legacy applications and should
  1.4819 +** be avoided in new projects.
  1.4820 +**
  1.4821 +** It is not safe to read or modify this variable in more than one
  1.4822 +** thread at a time.  It is not safe to read or modify this variable
  1.4823 +** if a [database connection] is being used at the same time in a separate
  1.4824 +** thread.
  1.4825 +** It is intended that this variable be set once
  1.4826 +** as part of process initialization and before any SQLite interface
  1.4827 +** routines have been called and that this variable remain unchanged
  1.4828 +** thereafter.
  1.4829 +**
  1.4830 +** ^The [temp_store_directory pragma] may modify this variable and cause
  1.4831 +** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
  1.4832 +** the [temp_store_directory pragma] always assumes that any string
  1.4833 +** that this variable points to is held in memory obtained from 
  1.4834 +** [sqlite3_malloc] and the pragma may attempt to free that memory
  1.4835 +** using [sqlite3_free].
  1.4836 +** Hence, if this variable is modified directly, either it should be
  1.4837 +** made NULL or made to point to memory obtained from [sqlite3_malloc]
  1.4838 +** or else the use of the [temp_store_directory pragma] should be avoided.
  1.4839 +** Except when requested by the [temp_store_directory pragma], SQLite
  1.4840 +** does not free the memory that sqlite3_temp_directory points to.  If
  1.4841 +** the application wants that memory to be freed, it must do
  1.4842 +** so itself, taking care to only do so after all [database connection]
  1.4843 +** objects have been destroyed.
  1.4844 +**
  1.4845 +** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
  1.4846 +** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
  1.4847 +** features that require the use of temporary files may fail.  Here is an
  1.4848 +** example of how to do this using C++ with the Windows Runtime:
  1.4849 +**
  1.4850 +** <blockquote><pre>
  1.4851 +** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
  1.4852 +** &nbsp;     TemporaryFolder->Path->Data();
  1.4853 +** char zPathBuf&#91;MAX_PATH + 1&#93;;
  1.4854 +** memset(zPathBuf, 0, sizeof(zPathBuf));
  1.4855 +** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
  1.4856 +** &nbsp;     NULL, NULL);
  1.4857 +** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
  1.4858 +** </pre></blockquote>
  1.4859 +*/
  1.4860 +SQLITE_API char *sqlite3_temp_directory;
  1.4861 +
  1.4862 +/*
  1.4863 +** CAPI3REF: Name Of The Folder Holding Database Files
  1.4864 +**
  1.4865 +** ^(If this global variable is made to point to a string which is
  1.4866 +** the name of a folder (a.k.a. directory), then all database files
  1.4867 +** specified with a relative pathname and created or accessed by
  1.4868 +** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
  1.4869 +** to be relative to that directory.)^ ^If this variable is a NULL
  1.4870 +** pointer, then SQLite assumes that all database files specified
  1.4871 +** with a relative pathname are relative to the current directory
  1.4872 +** for the process.  Only the windows VFS makes use of this global
  1.4873 +** variable; it is ignored by the unix VFS.
  1.4874 +**
  1.4875 +** Changing the value of this variable while a database connection is
  1.4876 +** open can result in a corrupt database.
  1.4877 +**
  1.4878 +** It is not safe to read or modify this variable in more than one
  1.4879 +** thread at a time.  It is not safe to read or modify this variable
  1.4880 +** if a [database connection] is being used at the same time in a separate
  1.4881 +** thread.
  1.4882 +** It is intended that this variable be set once
  1.4883 +** as part of process initialization and before any SQLite interface
  1.4884 +** routines have been called and that this variable remain unchanged
  1.4885 +** thereafter.
  1.4886 +**
  1.4887 +** ^The [data_store_directory pragma] may modify this variable and cause
  1.4888 +** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
  1.4889 +** the [data_store_directory pragma] always assumes that any string
  1.4890 +** that this variable points to is held in memory obtained from 
  1.4891 +** [sqlite3_malloc] and the pragma may attempt to free that memory
  1.4892 +** using [sqlite3_free].
  1.4893 +** Hence, if this variable is modified directly, either it should be
  1.4894 +** made NULL or made to point to memory obtained from [sqlite3_malloc]
  1.4895 +** or else the use of the [data_store_directory pragma] should be avoided.
  1.4896 +*/
  1.4897 +SQLITE_API char *sqlite3_data_directory;
  1.4898 +
  1.4899 +/*
  1.4900 +** CAPI3REF: Test For Auto-Commit Mode
  1.4901 +** KEYWORDS: {autocommit mode}
  1.4902 +**
  1.4903 +** ^The sqlite3_get_autocommit() interface returns non-zero or
  1.4904 +** zero if the given database connection is or is not in autocommit mode,
  1.4905 +** respectively.  ^Autocommit mode is on by default.
  1.4906 +** ^Autocommit mode is disabled by a [BEGIN] statement.
  1.4907 +** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
  1.4908 +**
  1.4909 +** If certain kinds of errors occur on a statement within a multi-statement
  1.4910 +** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
  1.4911 +** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
  1.4912 +** transaction might be rolled back automatically.  The only way to
  1.4913 +** find out whether SQLite automatically rolled back the transaction after
  1.4914 +** an error is to use this function.
  1.4915 +**
  1.4916 +** If another thread changes the autocommit status of the database
  1.4917 +** connection while this routine is running, then the return value
  1.4918 +** is undefined.
  1.4919 +*/
  1.4920 +SQLITE_API int sqlite3_get_autocommit(sqlite3*);
  1.4921 +
  1.4922 +/*
  1.4923 +** CAPI3REF: Find The Database Handle Of A Prepared Statement
  1.4924 +**
  1.4925 +** ^The sqlite3_db_handle interface returns the [database connection] handle
  1.4926 +** to which a [prepared statement] belongs.  ^The [database connection]
  1.4927 +** returned by sqlite3_db_handle is the same [database connection]
  1.4928 +** that was the first argument
  1.4929 +** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
  1.4930 +** create the statement in the first place.
  1.4931 +*/
  1.4932 +SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
  1.4933 +
  1.4934 +/*
  1.4935 +** CAPI3REF: Return The Filename For A Database Connection
  1.4936 +**
  1.4937 +** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
  1.4938 +** associated with database N of connection D.  ^The main database file
  1.4939 +** has the name "main".  If there is no attached database N on the database
  1.4940 +** connection D, or if database N is a temporary or in-memory database, then
  1.4941 +** a NULL pointer is returned.
  1.4942 +**
  1.4943 +** ^The filename returned by this function is the output of the
  1.4944 +** xFullPathname method of the [VFS].  ^In other words, the filename
  1.4945 +** will be an absolute pathname, even if the filename used
  1.4946 +** to open the database originally was a URI or relative pathname.
  1.4947 +*/
  1.4948 +SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
  1.4949 +
  1.4950 +/*
  1.4951 +** CAPI3REF: Determine if a database is read-only
  1.4952 +**
  1.4953 +** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
  1.4954 +** of connection D is read-only, 0 if it is read/write, or -1 if N is not
  1.4955 +** the name of a database on connection D.
  1.4956 +*/
  1.4957 +SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
  1.4958 +
  1.4959 +/*
  1.4960 +** CAPI3REF: Find the next prepared statement
  1.4961 +**
  1.4962 +** ^This interface returns a pointer to the next [prepared statement] after
  1.4963 +** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
  1.4964 +** then this interface returns a pointer to the first prepared statement
  1.4965 +** associated with the database connection pDb.  ^If no prepared statement
  1.4966 +** satisfies the conditions of this routine, it returns NULL.
  1.4967 +**
  1.4968 +** The [database connection] pointer D in a call to
  1.4969 +** [sqlite3_next_stmt(D,S)] must refer to an open database
  1.4970 +** connection and in particular must not be a NULL pointer.
  1.4971 +*/
  1.4972 +SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
  1.4973 +
  1.4974 +/*
  1.4975 +** CAPI3REF: Commit And Rollback Notification Callbacks
  1.4976 +**
  1.4977 +** ^The sqlite3_commit_hook() interface registers a callback
  1.4978 +** function to be invoked whenever a transaction is [COMMIT | committed].
  1.4979 +** ^Any callback set by a previous call to sqlite3_commit_hook()
  1.4980 +** for the same database connection is overridden.
  1.4981 +** ^The sqlite3_rollback_hook() interface registers a callback
  1.4982 +** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
  1.4983 +** ^Any callback set by a previous call to sqlite3_rollback_hook()
  1.4984 +** for the same database connection is overridden.
  1.4985 +** ^The pArg argument is passed through to the callback.
  1.4986 +** ^If the callback on a commit hook function returns non-zero,
  1.4987 +** then the commit is converted into a rollback.
  1.4988 +**
  1.4989 +** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
  1.4990 +** return the P argument from the previous call of the same function
  1.4991 +** on the same [database connection] D, or NULL for
  1.4992 +** the first call for each function on D.
  1.4993 +**
  1.4994 +** The commit and rollback hook callbacks are not reentrant.
  1.4995 +** The callback implementation must not do anything that will modify
  1.4996 +** the database connection that invoked the callback.  Any actions
  1.4997 +** to modify the database connection must be deferred until after the
  1.4998 +** completion of the [sqlite3_step()] call that triggered the commit
  1.4999 +** or rollback hook in the first place.
  1.5000 +** Note that running any other SQL statements, including SELECT statements,
  1.5001 +** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
  1.5002 +** the database connections for the meaning of "modify" in this paragraph.
  1.5003 +**
  1.5004 +** ^Registering a NULL function disables the callback.
  1.5005 +**
  1.5006 +** ^When the commit hook callback routine returns zero, the [COMMIT]
  1.5007 +** operation is allowed to continue normally.  ^If the commit hook
  1.5008 +** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
  1.5009 +** ^The rollback hook is invoked on a rollback that results from a commit
  1.5010 +** hook returning non-zero, just as it would be with any other rollback.
  1.5011 +**
  1.5012 +** ^For the purposes of this API, a transaction is said to have been
  1.5013 +** rolled back if an explicit "ROLLBACK" statement is executed, or
  1.5014 +** an error or constraint causes an implicit rollback to occur.
  1.5015 +** ^The rollback callback is not invoked if a transaction is
  1.5016 +** automatically rolled back because the database connection is closed.
  1.5017 +**
  1.5018 +** See also the [sqlite3_update_hook()] interface.
  1.5019 +*/
  1.5020 +SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
  1.5021 +SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
  1.5022 +
  1.5023 +/*
  1.5024 +** CAPI3REF: Data Change Notification Callbacks
  1.5025 +**
  1.5026 +** ^The sqlite3_update_hook() interface registers a callback function
  1.5027 +** with the [database connection] identified by the first argument
  1.5028 +** to be invoked whenever a row is updated, inserted or deleted in
  1.5029 +** a rowid table.
  1.5030 +** ^Any callback set by a previous call to this function
  1.5031 +** for the same database connection is overridden.
  1.5032 +**
  1.5033 +** ^The second argument is a pointer to the function to invoke when a
  1.5034 +** row is updated, inserted or deleted in a rowid table.
  1.5035 +** ^The first argument to the callback is a copy of the third argument
  1.5036 +** to sqlite3_update_hook().
  1.5037 +** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
  1.5038 +** or [SQLITE_UPDATE], depending on the operation that caused the callback
  1.5039 +** to be invoked.
  1.5040 +** ^The third and fourth arguments to the callback contain pointers to the
  1.5041 +** database and table name containing the affected row.
  1.5042 +** ^The final callback parameter is the [rowid] of the row.
  1.5043 +** ^In the case of an update, this is the [rowid] after the update takes place.
  1.5044 +**
  1.5045 +** ^(The update hook is not invoked when internal system tables are
  1.5046 +** modified (i.e. sqlite_master and sqlite_sequence).)^
  1.5047 +** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
  1.5048 +**
  1.5049 +** ^In the current implementation, the update hook
  1.5050 +** is not invoked when duplication rows are deleted because of an
  1.5051 +** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
  1.5052 +** invoked when rows are deleted using the [truncate optimization].
  1.5053 +** The exceptions defined in this paragraph might change in a future
  1.5054 +** release of SQLite.
  1.5055 +**
  1.5056 +** The update hook implementation must not do anything that will modify
  1.5057 +** the database connection that invoked the update hook.  Any actions
  1.5058 +** to modify the database connection must be deferred until after the
  1.5059 +** completion of the [sqlite3_step()] call that triggered the update hook.
  1.5060 +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
  1.5061 +** database connections for the meaning of "modify" in this paragraph.
  1.5062 +**
  1.5063 +** ^The sqlite3_update_hook(D,C,P) function
  1.5064 +** returns the P argument from the previous call
  1.5065 +** on the same [database connection] D, or NULL for
  1.5066 +** the first call on D.
  1.5067 +**
  1.5068 +** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
  1.5069 +** interfaces.
  1.5070 +*/
  1.5071 +SQLITE_API void *sqlite3_update_hook(
  1.5072 +  sqlite3*, 
  1.5073 +  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
  1.5074 +  void*
  1.5075 +);
  1.5076 +
  1.5077 +/*
  1.5078 +** CAPI3REF: Enable Or Disable Shared Pager Cache
  1.5079 +**
  1.5080 +** ^(This routine enables or disables the sharing of the database cache
  1.5081 +** and schema data structures between [database connection | connections]
  1.5082 +** to the same database. Sharing is enabled if the argument is true
  1.5083 +** and disabled if the argument is false.)^
  1.5084 +**
  1.5085 +** ^Cache sharing is enabled and disabled for an entire process.
  1.5086 +** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
  1.5087 +** sharing was enabled or disabled for each thread separately.
  1.5088 +**
  1.5089 +** ^(The cache sharing mode set by this interface effects all subsequent
  1.5090 +** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
  1.5091 +** Existing database connections continue use the sharing mode
  1.5092 +** that was in effect at the time they were opened.)^
  1.5093 +**
  1.5094 +** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
  1.5095 +** successfully.  An [error code] is returned otherwise.)^
  1.5096 +**
  1.5097 +** ^Shared cache is disabled by default. But this might change in
  1.5098 +** future releases of SQLite.  Applications that care about shared
  1.5099 +** cache setting should set it explicitly.
  1.5100 +**
  1.5101 +** This interface is threadsafe on processors where writing a
  1.5102 +** 32-bit integer is atomic.
  1.5103 +**
  1.5104 +** See Also:  [SQLite Shared-Cache Mode]
  1.5105 +*/
  1.5106 +SQLITE_API int sqlite3_enable_shared_cache(int);
  1.5107 +
  1.5108 +/*
  1.5109 +** CAPI3REF: Attempt To Free Heap Memory
  1.5110 +**
  1.5111 +** ^The sqlite3_release_memory() interface attempts to free N bytes
  1.5112 +** of heap memory by deallocating non-essential memory allocations
  1.5113 +** held by the database library.   Memory used to cache database
  1.5114 +** pages to improve performance is an example of non-essential memory.
  1.5115 +** ^sqlite3_release_memory() returns the number of bytes actually freed,
  1.5116 +** which might be more or less than the amount requested.
  1.5117 +** ^The sqlite3_release_memory() routine is a no-op returning zero
  1.5118 +** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
  1.5119 +**
  1.5120 +** See also: [sqlite3_db_release_memory()]
  1.5121 +*/
  1.5122 +SQLITE_API int sqlite3_release_memory(int);
  1.5123 +
  1.5124 +/*
  1.5125 +** CAPI3REF: Free Memory Used By A Database Connection
  1.5126 +**
  1.5127 +** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
  1.5128 +** memory as possible from database connection D. Unlike the
  1.5129 +** [sqlite3_release_memory()] interface, this interface is in effect even
  1.5130 +** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
  1.5131 +** omitted.
  1.5132 +**
  1.5133 +** See also: [sqlite3_release_memory()]
  1.5134 +*/
  1.5135 +SQLITE_API int sqlite3_db_release_memory(sqlite3*);
  1.5136 +
  1.5137 +/*
  1.5138 +** CAPI3REF: Impose A Limit On Heap Size
  1.5139 +**
  1.5140 +** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
  1.5141 +** soft limit on the amount of heap memory that may be allocated by SQLite.
  1.5142 +** ^SQLite strives to keep heap memory utilization below the soft heap
  1.5143 +** limit by reducing the number of pages held in the page cache
  1.5144 +** as heap memory usages approaches the limit.
  1.5145 +** ^The soft heap limit is "soft" because even though SQLite strives to stay
  1.5146 +** below the limit, it will exceed the limit rather than generate
  1.5147 +** an [SQLITE_NOMEM] error.  In other words, the soft heap limit 
  1.5148 +** is advisory only.
  1.5149 +**
  1.5150 +** ^The return value from sqlite3_soft_heap_limit64() is the size of
  1.5151 +** the soft heap limit prior to the call, or negative in the case of an
  1.5152 +** error.  ^If the argument N is negative
  1.5153 +** then no change is made to the soft heap limit.  Hence, the current
  1.5154 +** size of the soft heap limit can be determined by invoking
  1.5155 +** sqlite3_soft_heap_limit64() with a negative argument.
  1.5156 +**
  1.5157 +** ^If the argument N is zero then the soft heap limit is disabled.
  1.5158 +**
  1.5159 +** ^(The soft heap limit is not enforced in the current implementation
  1.5160 +** if one or more of following conditions are true:
  1.5161 +**
  1.5162 +** <ul>
  1.5163 +** <li> The soft heap limit is set to zero.
  1.5164 +** <li> Memory accounting is disabled using a combination of the
  1.5165 +**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
  1.5166 +**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
  1.5167 +** <li> An alternative page cache implementation is specified using
  1.5168 +**      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
  1.5169 +** <li> The page cache allocates from its own memory pool supplied
  1.5170 +**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
  1.5171 +**      from the heap.
  1.5172 +** </ul>)^
  1.5173 +**
  1.5174 +** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
  1.5175 +** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
  1.5176 +** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
  1.5177 +** the soft heap limit is enforced on every memory allocation.  Without
  1.5178 +** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
  1.5179 +** when memory is allocated by the page cache.  Testing suggests that because
  1.5180 +** the page cache is the predominate memory user in SQLite, most
  1.5181 +** applications will achieve adequate soft heap limit enforcement without
  1.5182 +** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
  1.5183 +**
  1.5184 +** The circumstances under which SQLite will enforce the soft heap limit may
  1.5185 +** changes in future releases of SQLite.
  1.5186 +*/
  1.5187 +SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
  1.5188 +
  1.5189 +/*
  1.5190 +** CAPI3REF: Deprecated Soft Heap Limit Interface
  1.5191 +** DEPRECATED
  1.5192 +**
  1.5193 +** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
  1.5194 +** interface.  This routine is provided for historical compatibility
  1.5195 +** only.  All new applications should use the
  1.5196 +** [sqlite3_soft_heap_limit64()] interface rather than this one.
  1.5197 +*/
  1.5198 +SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
  1.5199 +
  1.5200 +
  1.5201 +/*
  1.5202 +** CAPI3REF: Extract Metadata About A Column Of A Table
  1.5203 +**
  1.5204 +** ^This routine returns metadata about a specific column of a specific
  1.5205 +** database table accessible using the [database connection] handle
  1.5206 +** passed as the first function argument.
  1.5207 +**
  1.5208 +** ^The column is identified by the second, third and fourth parameters to
  1.5209 +** this function. ^The second parameter is either the name of the database
  1.5210 +** (i.e. "main", "temp", or an attached database) containing the specified
  1.5211 +** table or NULL. ^If it is NULL, then all attached databases are searched
  1.5212 +** for the table using the same algorithm used by the database engine to
  1.5213 +** resolve unqualified table references.
  1.5214 +**
  1.5215 +** ^The third and fourth parameters to this function are the table and column
  1.5216 +** name of the desired column, respectively. Neither of these parameters
  1.5217 +** may be NULL.
  1.5218 +**
  1.5219 +** ^Metadata is returned by writing to the memory locations passed as the 5th
  1.5220 +** and subsequent parameters to this function. ^Any of these arguments may be
  1.5221 +** NULL, in which case the corresponding element of metadata is omitted.
  1.5222 +**
  1.5223 +** ^(<blockquote>
  1.5224 +** <table border="1">
  1.5225 +** <tr><th> Parameter <th> Output<br>Type <th>  Description
  1.5226 +**
  1.5227 +** <tr><td> 5th <td> const char* <td> Data type
  1.5228 +** <tr><td> 6th <td> const char* <td> Name of default collation sequence
  1.5229 +** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
  1.5230 +** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
  1.5231 +** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
  1.5232 +** </table>
  1.5233 +** </blockquote>)^
  1.5234 +**
  1.5235 +** ^The memory pointed to by the character pointers returned for the
  1.5236 +** declaration type and collation sequence is valid only until the next
  1.5237 +** call to any SQLite API function.
  1.5238 +**
  1.5239 +** ^If the specified table is actually a view, an [error code] is returned.
  1.5240 +**
  1.5241 +** ^If the specified column is "rowid", "oid" or "_rowid_" and an
  1.5242 +** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
  1.5243 +** parameters are set for the explicitly declared column. ^(If there is no
  1.5244 +** explicitly declared [INTEGER PRIMARY KEY] column, then the output
  1.5245 +** parameters are set as follows:
  1.5246 +**
  1.5247 +** <pre>
  1.5248 +**     data type: "INTEGER"
  1.5249 +**     collation sequence: "BINARY"
  1.5250 +**     not null: 0
  1.5251 +**     primary key: 1
  1.5252 +**     auto increment: 0
  1.5253 +** </pre>)^
  1.5254 +**
  1.5255 +** ^(This function may load one or more schemas from database files. If an
  1.5256 +** error occurs during this process, or if the requested table or column
  1.5257 +** cannot be found, an [error code] is returned and an error message left
  1.5258 +** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
  1.5259 +**
  1.5260 +** ^This API is only available if the library was compiled with the
  1.5261 +** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
  1.5262 +*/
  1.5263 +SQLITE_API int sqlite3_table_column_metadata(
  1.5264 +  sqlite3 *db,                /* Connection handle */
  1.5265 +  const char *zDbName,        /* Database name or NULL */
  1.5266 +  const char *zTableName,     /* Table name */
  1.5267 +  const char *zColumnName,    /* Column name */
  1.5268 +  char const **pzDataType,    /* OUTPUT: Declared data type */
  1.5269 +  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
  1.5270 +  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
  1.5271 +  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
  1.5272 +  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
  1.5273 +);
  1.5274 +
  1.5275 +/*
  1.5276 +** CAPI3REF: Load An Extension
  1.5277 +**
  1.5278 +** ^This interface loads an SQLite extension library from the named file.
  1.5279 +**
  1.5280 +** ^The sqlite3_load_extension() interface attempts to load an
  1.5281 +** [SQLite extension] library contained in the file zFile.  If
  1.5282 +** the file cannot be loaded directly, attempts are made to load
  1.5283 +** with various operating-system specific extensions added.
  1.5284 +** So for example, if "samplelib" cannot be loaded, then names like
  1.5285 +** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
  1.5286 +** be tried also.
  1.5287 +**
  1.5288 +** ^The entry point is zProc.
  1.5289 +** ^(zProc may be 0, in which case SQLite will try to come up with an
  1.5290 +** entry point name on its own.  It first tries "sqlite3_extension_init".
  1.5291 +** If that does not work, it constructs a name "sqlite3_X_init" where the
  1.5292 +** X is consists of the lower-case equivalent of all ASCII alphabetic
  1.5293 +** characters in the filename from the last "/" to the first following
  1.5294 +** "." and omitting any initial "lib".)^
  1.5295 +** ^The sqlite3_load_extension() interface returns
  1.5296 +** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
  1.5297 +** ^If an error occurs and pzErrMsg is not 0, then the
  1.5298 +** [sqlite3_load_extension()] interface shall attempt to
  1.5299 +** fill *pzErrMsg with error message text stored in memory
  1.5300 +** obtained from [sqlite3_malloc()]. The calling function
  1.5301 +** should free this memory by calling [sqlite3_free()].
  1.5302 +**
  1.5303 +** ^Extension loading must be enabled using
  1.5304 +** [sqlite3_enable_load_extension()] prior to calling this API,
  1.5305 +** otherwise an error will be returned.
  1.5306 +**
  1.5307 +** See also the [load_extension() SQL function].
  1.5308 +*/
  1.5309 +SQLITE_API int sqlite3_load_extension(
  1.5310 +  sqlite3 *db,          /* Load the extension into this database connection */
  1.5311 +  const char *zFile,    /* Name of the shared library containing extension */
  1.5312 +  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
  1.5313 +  char **pzErrMsg       /* Put error message here if not 0 */
  1.5314 +);
  1.5315 +
  1.5316 +/*
  1.5317 +** CAPI3REF: Enable Or Disable Extension Loading
  1.5318 +**
  1.5319 +** ^So as not to open security holes in older applications that are
  1.5320 +** unprepared to deal with [extension loading], and as a means of disabling
  1.5321 +** [extension loading] while evaluating user-entered SQL, the following API
  1.5322 +** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
  1.5323 +**
  1.5324 +** ^Extension loading is off by default.
  1.5325 +** ^Call the sqlite3_enable_load_extension() routine with onoff==1
  1.5326 +** to turn extension loading on and call it with onoff==0 to turn
  1.5327 +** it back off again.
  1.5328 +*/
  1.5329 +SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
  1.5330 +
  1.5331 +/*
  1.5332 +** CAPI3REF: Automatically Load Statically Linked Extensions
  1.5333 +**
  1.5334 +** ^This interface causes the xEntryPoint() function to be invoked for
  1.5335 +** each new [database connection] that is created.  The idea here is that
  1.5336 +** xEntryPoint() is the entry point for a statically linked [SQLite extension]
  1.5337 +** that is to be automatically loaded into all new database connections.
  1.5338 +**
  1.5339 +** ^(Even though the function prototype shows that xEntryPoint() takes
  1.5340 +** no arguments and returns void, SQLite invokes xEntryPoint() with three
  1.5341 +** arguments and expects and integer result as if the signature of the
  1.5342 +** entry point where as follows:
  1.5343 +**
  1.5344 +** <blockquote><pre>
  1.5345 +** &nbsp;  int xEntryPoint(
  1.5346 +** &nbsp;    sqlite3 *db,
  1.5347 +** &nbsp;    const char **pzErrMsg,
  1.5348 +** &nbsp;    const struct sqlite3_api_routines *pThunk
  1.5349 +** &nbsp;  );
  1.5350 +** </pre></blockquote>)^
  1.5351 +**
  1.5352 +** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
  1.5353 +** point to an appropriate error message (obtained from [sqlite3_mprintf()])
  1.5354 +** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
  1.5355 +** is NULL before calling the xEntryPoint().  ^SQLite will invoke
  1.5356 +** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
  1.5357 +** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
  1.5358 +** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
  1.5359 +**
  1.5360 +** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
  1.5361 +** on the list of automatic extensions is a harmless no-op. ^No entry point
  1.5362 +** will be called more than once for each database connection that is opened.
  1.5363 +**
  1.5364 +** See also: [sqlite3_reset_auto_extension()]
  1.5365 +** and [sqlite3_cancel_auto_extension()]
  1.5366 +*/
  1.5367 +SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
  1.5368 +
  1.5369 +/*
  1.5370 +** CAPI3REF: Cancel Automatic Extension Loading
  1.5371 +**
  1.5372 +** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
  1.5373 +** initialization routine X that was registered using a prior call to
  1.5374 +** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
  1.5375 +** routine returns 1 if initialization routine X was successfully 
  1.5376 +** unregistered and it returns 0 if X was not on the list of initialization
  1.5377 +** routines.
  1.5378 +*/
  1.5379 +SQLITE_API int sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
  1.5380 +
  1.5381 +/*
  1.5382 +** CAPI3REF: Reset Automatic Extension Loading
  1.5383 +**
  1.5384 +** ^This interface disables all automatic extensions previously
  1.5385 +** registered using [sqlite3_auto_extension()].
  1.5386 +*/
  1.5387 +SQLITE_API void sqlite3_reset_auto_extension(void);
  1.5388 +
  1.5389 +/*
  1.5390 +** The interface to the virtual-table mechanism is currently considered
  1.5391 +** to be experimental.  The interface might change in incompatible ways.
  1.5392 +** If this is a problem for you, do not use the interface at this time.
  1.5393 +**
  1.5394 +** When the virtual-table mechanism stabilizes, we will declare the
  1.5395 +** interface fixed, support it indefinitely, and remove this comment.
  1.5396 +*/
  1.5397 +
  1.5398 +/*
  1.5399 +** Structures used by the virtual table interface
  1.5400 +*/
  1.5401 +typedef struct sqlite3_vtab sqlite3_vtab;
  1.5402 +typedef struct sqlite3_index_info sqlite3_index_info;
  1.5403 +typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
  1.5404 +typedef struct sqlite3_module sqlite3_module;
  1.5405 +
  1.5406 +/*
  1.5407 +** CAPI3REF: Virtual Table Object
  1.5408 +** KEYWORDS: sqlite3_module {virtual table module}
  1.5409 +**
  1.5410 +** This structure, sometimes called a "virtual table module", 
  1.5411 +** defines the implementation of a [virtual tables].  
  1.5412 +** This structure consists mostly of methods for the module.
  1.5413 +**
  1.5414 +** ^A virtual table module is created by filling in a persistent
  1.5415 +** instance of this structure and passing a pointer to that instance
  1.5416 +** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
  1.5417 +** ^The registration remains valid until it is replaced by a different
  1.5418 +** module or until the [database connection] closes.  The content
  1.5419 +** of this structure must not change while it is registered with
  1.5420 +** any database connection.
  1.5421 +*/
  1.5422 +struct sqlite3_module {
  1.5423 +  int iVersion;
  1.5424 +  int (*xCreate)(sqlite3*, void *pAux,
  1.5425 +               int argc, const char *const*argv,
  1.5426 +               sqlite3_vtab **ppVTab, char**);
  1.5427 +  int (*xConnect)(sqlite3*, void *pAux,
  1.5428 +               int argc, const char *const*argv,
  1.5429 +               sqlite3_vtab **ppVTab, char**);
  1.5430 +  int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
  1.5431 +  int (*xDisconnect)(sqlite3_vtab *pVTab);
  1.5432 +  int (*xDestroy)(sqlite3_vtab *pVTab);
  1.5433 +  int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
  1.5434 +  int (*xClose)(sqlite3_vtab_cursor*);
  1.5435 +  int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
  1.5436 +                int argc, sqlite3_value **argv);
  1.5437 +  int (*xNext)(sqlite3_vtab_cursor*);
  1.5438 +  int (*xEof)(sqlite3_vtab_cursor*);
  1.5439 +  int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
  1.5440 +  int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
  1.5441 +  int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
  1.5442 +  int (*xBegin)(sqlite3_vtab *pVTab);
  1.5443 +  int (*xSync)(sqlite3_vtab *pVTab);
  1.5444 +  int (*xCommit)(sqlite3_vtab *pVTab);
  1.5445 +  int (*xRollback)(sqlite3_vtab *pVTab);
  1.5446 +  int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
  1.5447 +                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
  1.5448 +                       void **ppArg);
  1.5449 +  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
  1.5450 +  /* The methods above are in version 1 of the sqlite_module object. Those 
  1.5451 +  ** below are for version 2 and greater. */
  1.5452 +  int (*xSavepoint)(sqlite3_vtab *pVTab, int);
  1.5453 +  int (*xRelease)(sqlite3_vtab *pVTab, int);
  1.5454 +  int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
  1.5455 +};
  1.5456 +
  1.5457 +/*
  1.5458 +** CAPI3REF: Virtual Table Indexing Information
  1.5459 +** KEYWORDS: sqlite3_index_info
  1.5460 +**
  1.5461 +** The sqlite3_index_info structure and its substructures is used as part
  1.5462 +** of the [virtual table] interface to
  1.5463 +** pass information into and receive the reply from the [xBestIndex]
  1.5464 +** method of a [virtual table module].  The fields under **Inputs** are the
  1.5465 +** inputs to xBestIndex and are read-only.  xBestIndex inserts its
  1.5466 +** results into the **Outputs** fields.
  1.5467 +**
  1.5468 +** ^(The aConstraint[] array records WHERE clause constraints of the form:
  1.5469 +**
  1.5470 +** <blockquote>column OP expr</blockquote>
  1.5471 +**
  1.5472 +** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
  1.5473 +** stored in aConstraint[].op using one of the
  1.5474 +** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
  1.5475 +** ^(The index of the column is stored in
  1.5476 +** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
  1.5477 +** expr on the right-hand side can be evaluated (and thus the constraint
  1.5478 +** is usable) and false if it cannot.)^
  1.5479 +**
  1.5480 +** ^The optimizer automatically inverts terms of the form "expr OP column"
  1.5481 +** and makes other simplifications to the WHERE clause in an attempt to
  1.5482 +** get as many WHERE clause terms into the form shown above as possible.
  1.5483 +** ^The aConstraint[] array only reports WHERE clause terms that are
  1.5484 +** relevant to the particular virtual table being queried.
  1.5485 +**
  1.5486 +** ^Information about the ORDER BY clause is stored in aOrderBy[].
  1.5487 +** ^Each term of aOrderBy records a column of the ORDER BY clause.
  1.5488 +**
  1.5489 +** The [xBestIndex] method must fill aConstraintUsage[] with information
  1.5490 +** about what parameters to pass to xFilter.  ^If argvIndex>0 then
  1.5491 +** the right-hand side of the corresponding aConstraint[] is evaluated
  1.5492 +** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
  1.5493 +** is true, then the constraint is assumed to be fully handled by the
  1.5494 +** virtual table and is not checked again by SQLite.)^
  1.5495 +**
  1.5496 +** ^The idxNum and idxPtr values are recorded and passed into the
  1.5497 +** [xFilter] method.
  1.5498 +** ^[sqlite3_free()] is used to free idxPtr if and only if
  1.5499 +** needToFreeIdxPtr is true.
  1.5500 +**
  1.5501 +** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
  1.5502 +** the correct order to satisfy the ORDER BY clause so that no separate
  1.5503 +** sorting step is required.
  1.5504 +**
  1.5505 +** ^The estimatedCost value is an estimate of the cost of a particular
  1.5506 +** strategy. A cost of N indicates that the cost of the strategy is similar
  1.5507 +** to a linear scan of an SQLite table with N rows. A cost of log(N) 
  1.5508 +** indicates that the expense of the operation is similar to that of a
  1.5509 +** binary search on a unique indexed field of an SQLite table with N rows.
  1.5510 +**
  1.5511 +** ^The estimatedRows value is an estimate of the number of rows that
  1.5512 +** will be returned by the strategy.
  1.5513 +**
  1.5514 +** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
  1.5515 +** structure for SQLite version 3.8.2. If a virtual table extension is
  1.5516 +** used with an SQLite version earlier than 3.8.2, the results of attempting 
  1.5517 +** to read or write the estimatedRows field are undefined (but are likely 
  1.5518 +** to included crashing the application). The estimatedRows field should
  1.5519 +** therefore only be used if [sqlite3_libversion_number()] returns a
  1.5520 +** value greater than or equal to 3008002.
  1.5521 +*/
  1.5522 +struct sqlite3_index_info {
  1.5523 +  /* Inputs */
  1.5524 +  int nConstraint;           /* Number of entries in aConstraint */
  1.5525 +  struct sqlite3_index_constraint {
  1.5526 +     int iColumn;              /* Column on left-hand side of constraint */
  1.5527 +     unsigned char op;         /* Constraint operator */
  1.5528 +     unsigned char usable;     /* True if this constraint is usable */
  1.5529 +     int iTermOffset;          /* Used internally - xBestIndex should ignore */
  1.5530 +  } *aConstraint;            /* Table of WHERE clause constraints */
  1.5531 +  int nOrderBy;              /* Number of terms in the ORDER BY clause */
  1.5532 +  struct sqlite3_index_orderby {
  1.5533 +     int iColumn;              /* Column number */
  1.5534 +     unsigned char desc;       /* True for DESC.  False for ASC. */
  1.5535 +  } *aOrderBy;               /* The ORDER BY clause */
  1.5536 +  /* Outputs */
  1.5537 +  struct sqlite3_index_constraint_usage {
  1.5538 +    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
  1.5539 +    unsigned char omit;      /* Do not code a test for this constraint */
  1.5540 +  } *aConstraintUsage;
  1.5541 +  int idxNum;                /* Number used to identify the index */
  1.5542 +  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
  1.5543 +  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
  1.5544 +  int orderByConsumed;       /* True if output is already ordered */
  1.5545 +  double estimatedCost;           /* Estimated cost of using this index */
  1.5546 +  /* Fields below are only available in SQLite 3.8.2 and later */
  1.5547 +  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
  1.5548 +};
  1.5549 +
  1.5550 +/*
  1.5551 +** CAPI3REF: Virtual Table Constraint Operator Codes
  1.5552 +**
  1.5553 +** These macros defined the allowed values for the
  1.5554 +** [sqlite3_index_info].aConstraint[].op field.  Each value represents
  1.5555 +** an operator that is part of a constraint term in the wHERE clause of
  1.5556 +** a query that uses a [virtual table].
  1.5557 +*/
  1.5558 +#define SQLITE_INDEX_CONSTRAINT_EQ    2
  1.5559 +#define SQLITE_INDEX_CONSTRAINT_GT    4
  1.5560 +#define SQLITE_INDEX_CONSTRAINT_LE    8
  1.5561 +#define SQLITE_INDEX_CONSTRAINT_LT    16
  1.5562 +#define SQLITE_INDEX_CONSTRAINT_GE    32
  1.5563 +#define SQLITE_INDEX_CONSTRAINT_MATCH 64
  1.5564 +
  1.5565 +/*
  1.5566 +** CAPI3REF: Register A Virtual Table Implementation
  1.5567 +**
  1.5568 +** ^These routines are used to register a new [virtual table module] name.
  1.5569 +** ^Module names must be registered before
  1.5570 +** creating a new [virtual table] using the module and before using a
  1.5571 +** preexisting [virtual table] for the module.
  1.5572 +**
  1.5573 +** ^The module name is registered on the [database connection] specified
  1.5574 +** by the first parameter.  ^The name of the module is given by the 
  1.5575 +** second parameter.  ^The third parameter is a pointer to
  1.5576 +** the implementation of the [virtual table module].   ^The fourth
  1.5577 +** parameter is an arbitrary client data pointer that is passed through
  1.5578 +** into the [xCreate] and [xConnect] methods of the virtual table module
  1.5579 +** when a new virtual table is be being created or reinitialized.
  1.5580 +**
  1.5581 +** ^The sqlite3_create_module_v2() interface has a fifth parameter which
  1.5582 +** is a pointer to a destructor for the pClientData.  ^SQLite will
  1.5583 +** invoke the destructor function (if it is not NULL) when SQLite
  1.5584 +** no longer needs the pClientData pointer.  ^The destructor will also
  1.5585 +** be invoked if the call to sqlite3_create_module_v2() fails.
  1.5586 +** ^The sqlite3_create_module()
  1.5587 +** interface is equivalent to sqlite3_create_module_v2() with a NULL
  1.5588 +** destructor.
  1.5589 +*/
  1.5590 +SQLITE_API int sqlite3_create_module(
  1.5591 +  sqlite3 *db,               /* SQLite connection to register module with */
  1.5592 +  const char *zName,         /* Name of the module */
  1.5593 +  const sqlite3_module *p,   /* Methods for the module */
  1.5594 +  void *pClientData          /* Client data for xCreate/xConnect */
  1.5595 +);
  1.5596 +SQLITE_API int sqlite3_create_module_v2(
  1.5597 +  sqlite3 *db,               /* SQLite connection to register module with */
  1.5598 +  const char *zName,         /* Name of the module */
  1.5599 +  const sqlite3_module *p,   /* Methods for the module */
  1.5600 +  void *pClientData,         /* Client data for xCreate/xConnect */
  1.5601 +  void(*xDestroy)(void*)     /* Module destructor function */
  1.5602 +);
  1.5603 +
  1.5604 +/*
  1.5605 +** CAPI3REF: Virtual Table Instance Object
  1.5606 +** KEYWORDS: sqlite3_vtab
  1.5607 +**
  1.5608 +** Every [virtual table module] implementation uses a subclass
  1.5609 +** of this object to describe a particular instance
  1.5610 +** of the [virtual table].  Each subclass will
  1.5611 +** be tailored to the specific needs of the module implementation.
  1.5612 +** The purpose of this superclass is to define certain fields that are
  1.5613 +** common to all module implementations.
  1.5614 +**
  1.5615 +** ^Virtual tables methods can set an error message by assigning a
  1.5616 +** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
  1.5617 +** take care that any prior string is freed by a call to [sqlite3_free()]
  1.5618 +** prior to assigning a new string to zErrMsg.  ^After the error message
  1.5619 +** is delivered up to the client application, the string will be automatically
  1.5620 +** freed by sqlite3_free() and the zErrMsg field will be zeroed.
  1.5621 +*/
  1.5622 +struct sqlite3_vtab {
  1.5623 +  const sqlite3_module *pModule;  /* The module for this virtual table */
  1.5624 +  int nRef;                       /* NO LONGER USED */
  1.5625 +  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
  1.5626 +  /* Virtual table implementations will typically add additional fields */
  1.5627 +};
  1.5628 +
  1.5629 +/*
  1.5630 +** CAPI3REF: Virtual Table Cursor Object
  1.5631 +** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
  1.5632 +**
  1.5633 +** Every [virtual table module] implementation uses a subclass of the
  1.5634 +** following structure to describe cursors that point into the
  1.5635 +** [virtual table] and are used
  1.5636 +** to loop through the virtual table.  Cursors are created using the
  1.5637 +** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
  1.5638 +** by the [sqlite3_module.xClose | xClose] method.  Cursors are used
  1.5639 +** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
  1.5640 +** of the module.  Each module implementation will define
  1.5641 +** the content of a cursor structure to suit its own needs.
  1.5642 +**
  1.5643 +** This superclass exists in order to define fields of the cursor that
  1.5644 +** are common to all implementations.
  1.5645 +*/
  1.5646 +struct sqlite3_vtab_cursor {
  1.5647 +  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
  1.5648 +  /* Virtual table implementations will typically add additional fields */
  1.5649 +};
  1.5650 +
  1.5651 +/*
  1.5652 +** CAPI3REF: Declare The Schema Of A Virtual Table
  1.5653 +**
  1.5654 +** ^The [xCreate] and [xConnect] methods of a
  1.5655 +** [virtual table module] call this interface
  1.5656 +** to declare the format (the names and datatypes of the columns) of
  1.5657 +** the virtual tables they implement.
  1.5658 +*/
  1.5659 +SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
  1.5660 +
  1.5661 +/*
  1.5662 +** CAPI3REF: Overload A Function For A Virtual Table
  1.5663 +**
  1.5664 +** ^(Virtual tables can provide alternative implementations of functions
  1.5665 +** using the [xFindFunction] method of the [virtual table module].  
  1.5666 +** But global versions of those functions
  1.5667 +** must exist in order to be overloaded.)^
  1.5668 +**
  1.5669 +** ^(This API makes sure a global version of a function with a particular
  1.5670 +** name and number of parameters exists.  If no such function exists
  1.5671 +** before this API is called, a new function is created.)^  ^The implementation
  1.5672 +** of the new function always causes an exception to be thrown.  So
  1.5673 +** the new function is not good for anything by itself.  Its only
  1.5674 +** purpose is to be a placeholder function that can be overloaded
  1.5675 +** by a [virtual table].
  1.5676 +*/
  1.5677 +SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
  1.5678 +
  1.5679 +/*
  1.5680 +** The interface to the virtual-table mechanism defined above (back up
  1.5681 +** to a comment remarkably similar to this one) is currently considered
  1.5682 +** to be experimental.  The interface might change in incompatible ways.
  1.5683 +** If this is a problem for you, do not use the interface at this time.
  1.5684 +**
  1.5685 +** When the virtual-table mechanism stabilizes, we will declare the
  1.5686 +** interface fixed, support it indefinitely, and remove this comment.
  1.5687 +*/
  1.5688 +
  1.5689 +/*
  1.5690 +** CAPI3REF: A Handle To An Open BLOB
  1.5691 +** KEYWORDS: {BLOB handle} {BLOB handles}
  1.5692 +**
  1.5693 +** An instance of this object represents an open BLOB on which
  1.5694 +** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
  1.5695 +** ^Objects of this type are created by [sqlite3_blob_open()]
  1.5696 +** and destroyed by [sqlite3_blob_close()].
  1.5697 +** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
  1.5698 +** can be used to read or write small subsections of the BLOB.
  1.5699 +** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
  1.5700 +*/
  1.5701 +typedef struct sqlite3_blob sqlite3_blob;
  1.5702 +
  1.5703 +/*
  1.5704 +** CAPI3REF: Open A BLOB For Incremental I/O
  1.5705 +**
  1.5706 +** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
  1.5707 +** in row iRow, column zColumn, table zTable in database zDb;
  1.5708 +** in other words, the same BLOB that would be selected by:
  1.5709 +**
  1.5710 +** <pre>
  1.5711 +**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
  1.5712 +** </pre>)^
  1.5713 +**
  1.5714 +** ^If the flags parameter is non-zero, then the BLOB is opened for read
  1.5715 +** and write access. ^If it is zero, the BLOB is opened for read access.
  1.5716 +** ^It is not possible to open a column that is part of an index or primary 
  1.5717 +** key for writing. ^If [foreign key constraints] are enabled, it is 
  1.5718 +** not possible to open a column that is part of a [child key] for writing.
  1.5719 +**
  1.5720 +** ^Note that the database name is not the filename that contains
  1.5721 +** the database but rather the symbolic name of the database that
  1.5722 +** appears after the AS keyword when the database is connected using [ATTACH].
  1.5723 +** ^For the main database file, the database name is "main".
  1.5724 +** ^For TEMP tables, the database name is "temp".
  1.5725 +**
  1.5726 +** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
  1.5727 +** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
  1.5728 +** to be a null pointer.)^
  1.5729 +** ^This function sets the [database connection] error code and message
  1.5730 +** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
  1.5731 +** functions. ^Note that the *ppBlob variable is always initialized in a
  1.5732 +** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
  1.5733 +** regardless of the success or failure of this routine.
  1.5734 +**
  1.5735 +** ^(If the row that a BLOB handle points to is modified by an
  1.5736 +** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
  1.5737 +** then the BLOB handle is marked as "expired".
  1.5738 +** This is true if any column of the row is changed, even a column
  1.5739 +** other than the one the BLOB handle is open on.)^
  1.5740 +** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
  1.5741 +** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
  1.5742 +** ^(Changes written into a BLOB prior to the BLOB expiring are not
  1.5743 +** rolled back by the expiration of the BLOB.  Such changes will eventually
  1.5744 +** commit if the transaction continues to completion.)^
  1.5745 +**
  1.5746 +** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
  1.5747 +** the opened blob.  ^The size of a blob may not be changed by this
  1.5748 +** interface.  Use the [UPDATE] SQL command to change the size of a
  1.5749 +** blob.
  1.5750 +**
  1.5751 +** ^The [sqlite3_blob_open()] interface will fail for a [WITHOUT ROWID]
  1.5752 +** table.  Incremental BLOB I/O is not possible on [WITHOUT ROWID] tables.
  1.5753 +**
  1.5754 +** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
  1.5755 +** and the built-in [zeroblob] SQL function can be used, if desired,
  1.5756 +** to create an empty, zero-filled blob in which to read or write using
  1.5757 +** this interface.
  1.5758 +**
  1.5759 +** To avoid a resource leak, every open [BLOB handle] should eventually
  1.5760 +** be released by a call to [sqlite3_blob_close()].
  1.5761 +*/
  1.5762 +SQLITE_API int sqlite3_blob_open(
  1.5763 +  sqlite3*,
  1.5764 +  const char *zDb,
  1.5765 +  const char *zTable,
  1.5766 +  const char *zColumn,
  1.5767 +  sqlite3_int64 iRow,
  1.5768 +  int flags,
  1.5769 +  sqlite3_blob **ppBlob
  1.5770 +);
  1.5771 +
  1.5772 +/*
  1.5773 +** CAPI3REF: Move a BLOB Handle to a New Row
  1.5774 +**
  1.5775 +** ^This function is used to move an existing blob handle so that it points
  1.5776 +** to a different row of the same database table. ^The new row is identified
  1.5777 +** by the rowid value passed as the second argument. Only the row can be
  1.5778 +** changed. ^The database, table and column on which the blob handle is open
  1.5779 +** remain the same. Moving an existing blob handle to a new row can be
  1.5780 +** faster than closing the existing handle and opening a new one.
  1.5781 +**
  1.5782 +** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
  1.5783 +** it must exist and there must be either a blob or text value stored in
  1.5784 +** the nominated column.)^ ^If the new row is not present in the table, or if
  1.5785 +** it does not contain a blob or text value, or if another error occurs, an
  1.5786 +** SQLite error code is returned and the blob handle is considered aborted.
  1.5787 +** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
  1.5788 +** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
  1.5789 +** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
  1.5790 +** always returns zero.
  1.5791 +**
  1.5792 +** ^This function sets the database handle error code and message.
  1.5793 +*/
  1.5794 +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
  1.5795 +
  1.5796 +/*
  1.5797 +** CAPI3REF: Close A BLOB Handle
  1.5798 +**
  1.5799 +** ^Closes an open [BLOB handle].
  1.5800 +**
  1.5801 +** ^Closing a BLOB shall cause the current transaction to commit
  1.5802 +** if there are no other BLOBs, no pending prepared statements, and the
  1.5803 +** database connection is in [autocommit mode].
  1.5804 +** ^If any writes were made to the BLOB, they might be held in cache
  1.5805 +** until the close operation if they will fit.
  1.5806 +**
  1.5807 +** ^(Closing the BLOB often forces the changes
  1.5808 +** out to disk and so if any I/O errors occur, they will likely occur
  1.5809 +** at the time when the BLOB is closed.  Any errors that occur during
  1.5810 +** closing are reported as a non-zero return value.)^
  1.5811 +**
  1.5812 +** ^(The BLOB is closed unconditionally.  Even if this routine returns
  1.5813 +** an error code, the BLOB is still closed.)^
  1.5814 +**
  1.5815 +** ^Calling this routine with a null pointer (such as would be returned
  1.5816 +** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
  1.5817 +*/
  1.5818 +SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
  1.5819 +
  1.5820 +/*
  1.5821 +** CAPI3REF: Return The Size Of An Open BLOB
  1.5822 +**
  1.5823 +** ^Returns the size in bytes of the BLOB accessible via the 
  1.5824 +** successfully opened [BLOB handle] in its only argument.  ^The
  1.5825 +** incremental blob I/O routines can only read or overwriting existing
  1.5826 +** blob content; they cannot change the size of a blob.
  1.5827 +**
  1.5828 +** This routine only works on a [BLOB handle] which has been created
  1.5829 +** by a prior successful call to [sqlite3_blob_open()] and which has not
  1.5830 +** been closed by [sqlite3_blob_close()].  Passing any other pointer in
  1.5831 +** to this routine results in undefined and probably undesirable behavior.
  1.5832 +*/
  1.5833 +SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
  1.5834 +
  1.5835 +/*
  1.5836 +** CAPI3REF: Read Data From A BLOB Incrementally
  1.5837 +**
  1.5838 +** ^(This function is used to read data from an open [BLOB handle] into a
  1.5839 +** caller-supplied buffer. N bytes of data are copied into buffer Z
  1.5840 +** from the open BLOB, starting at offset iOffset.)^
  1.5841 +**
  1.5842 +** ^If offset iOffset is less than N bytes from the end of the BLOB,
  1.5843 +** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is
  1.5844 +** less than zero, [SQLITE_ERROR] is returned and no data is read.
  1.5845 +** ^The size of the blob (and hence the maximum value of N+iOffset)
  1.5846 +** can be determined using the [sqlite3_blob_bytes()] interface.
  1.5847 +**
  1.5848 +** ^An attempt to read from an expired [BLOB handle] fails with an
  1.5849 +** error code of [SQLITE_ABORT].
  1.5850 +**
  1.5851 +** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
  1.5852 +** Otherwise, an [error code] or an [extended error code] is returned.)^
  1.5853 +**
  1.5854 +** This routine only works on a [BLOB handle] which has been created
  1.5855 +** by a prior successful call to [sqlite3_blob_open()] and which has not
  1.5856 +** been closed by [sqlite3_blob_close()].  Passing any other pointer in
  1.5857 +** to this routine results in undefined and probably undesirable behavior.
  1.5858 +**
  1.5859 +** See also: [sqlite3_blob_write()].
  1.5860 +*/
  1.5861 +SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
  1.5862 +
  1.5863 +/*
  1.5864 +** CAPI3REF: Write Data Into A BLOB Incrementally
  1.5865 +**
  1.5866 +** ^This function is used to write data into an open [BLOB handle] from a
  1.5867 +** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
  1.5868 +** into the open BLOB, starting at offset iOffset.
  1.5869 +**
  1.5870 +** ^If the [BLOB handle] passed as the first argument was not opened for
  1.5871 +** writing (the flags parameter to [sqlite3_blob_open()] was zero),
  1.5872 +** this function returns [SQLITE_READONLY].
  1.5873 +**
  1.5874 +** ^This function may only modify the contents of the BLOB; it is
  1.5875 +** not possible to increase the size of a BLOB using this API.
  1.5876 +** ^If offset iOffset is less than N bytes from the end of the BLOB,
  1.5877 +** [SQLITE_ERROR] is returned and no data is written.  ^If N is
  1.5878 +** less than zero [SQLITE_ERROR] is returned and no data is written.
  1.5879 +** The size of the BLOB (and hence the maximum value of N+iOffset)
  1.5880 +** can be determined using the [sqlite3_blob_bytes()] interface.
  1.5881 +**
  1.5882 +** ^An attempt to write to an expired [BLOB handle] fails with an
  1.5883 +** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
  1.5884 +** before the [BLOB handle] expired are not rolled back by the
  1.5885 +** expiration of the handle, though of course those changes might
  1.5886 +** have been overwritten by the statement that expired the BLOB handle
  1.5887 +** or by other independent statements.
  1.5888 +**
  1.5889 +** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
  1.5890 +** Otherwise, an  [error code] or an [extended error code] is returned.)^
  1.5891 +**
  1.5892 +** This routine only works on a [BLOB handle] which has been created
  1.5893 +** by a prior successful call to [sqlite3_blob_open()] and which has not
  1.5894 +** been closed by [sqlite3_blob_close()].  Passing any other pointer in
  1.5895 +** to this routine results in undefined and probably undesirable behavior.
  1.5896 +**
  1.5897 +** See also: [sqlite3_blob_read()].
  1.5898 +*/
  1.5899 +SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
  1.5900 +
  1.5901 +/*
  1.5902 +** CAPI3REF: Virtual File System Objects
  1.5903 +**
  1.5904 +** A virtual filesystem (VFS) is an [sqlite3_vfs] object
  1.5905 +** that SQLite uses to interact
  1.5906 +** with the underlying operating system.  Most SQLite builds come with a
  1.5907 +** single default VFS that is appropriate for the host computer.
  1.5908 +** New VFSes can be registered and existing VFSes can be unregistered.
  1.5909 +** The following interfaces are provided.
  1.5910 +**
  1.5911 +** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
  1.5912 +** ^Names are case sensitive.
  1.5913 +** ^Names are zero-terminated UTF-8 strings.
  1.5914 +** ^If there is no match, a NULL pointer is returned.
  1.5915 +** ^If zVfsName is NULL then the default VFS is returned.
  1.5916 +**
  1.5917 +** ^New VFSes are registered with sqlite3_vfs_register().
  1.5918 +** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
  1.5919 +** ^The same VFS can be registered multiple times without injury.
  1.5920 +** ^To make an existing VFS into the default VFS, register it again
  1.5921 +** with the makeDflt flag set.  If two different VFSes with the
  1.5922 +** same name are registered, the behavior is undefined.  If a
  1.5923 +** VFS is registered with a name that is NULL or an empty string,
  1.5924 +** then the behavior is undefined.
  1.5925 +**
  1.5926 +** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
  1.5927 +** ^(If the default VFS is unregistered, another VFS is chosen as
  1.5928 +** the default.  The choice for the new VFS is arbitrary.)^
  1.5929 +*/
  1.5930 +SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
  1.5931 +SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
  1.5932 +SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
  1.5933 +
  1.5934 +/*
  1.5935 +** CAPI3REF: Mutexes
  1.5936 +**
  1.5937 +** The SQLite core uses these routines for thread
  1.5938 +** synchronization. Though they are intended for internal
  1.5939 +** use by SQLite, code that links against SQLite is
  1.5940 +** permitted to use any of these routines.
  1.5941 +**
  1.5942 +** The SQLite source code contains multiple implementations
  1.5943 +** of these mutex routines.  An appropriate implementation
  1.5944 +** is selected automatically at compile-time.  ^(The following
  1.5945 +** implementations are available in the SQLite core:
  1.5946 +**
  1.5947 +** <ul>
  1.5948 +** <li>   SQLITE_MUTEX_PTHREADS
  1.5949 +** <li>   SQLITE_MUTEX_W32
  1.5950 +** <li>   SQLITE_MUTEX_NOOP
  1.5951 +** </ul>)^
  1.5952 +**
  1.5953 +** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
  1.5954 +** that does no real locking and is appropriate for use in
  1.5955 +** a single-threaded application.  ^The SQLITE_MUTEX_PTHREADS and
  1.5956 +** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
  1.5957 +** and Windows.
  1.5958 +**
  1.5959 +** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
  1.5960 +** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
  1.5961 +** implementation is included with the library. In this case the
  1.5962 +** application must supply a custom mutex implementation using the
  1.5963 +** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
  1.5964 +** before calling sqlite3_initialize() or any other public sqlite3_
  1.5965 +** function that calls sqlite3_initialize().)^
  1.5966 +**
  1.5967 +** ^The sqlite3_mutex_alloc() routine allocates a new
  1.5968 +** mutex and returns a pointer to it. ^If it returns NULL
  1.5969 +** that means that a mutex could not be allocated.  ^SQLite
  1.5970 +** will unwind its stack and return an error.  ^(The argument
  1.5971 +** to sqlite3_mutex_alloc() is one of these integer constants:
  1.5972 +**
  1.5973 +** <ul>
  1.5974 +** <li>  SQLITE_MUTEX_FAST
  1.5975 +** <li>  SQLITE_MUTEX_RECURSIVE
  1.5976 +** <li>  SQLITE_MUTEX_STATIC_MASTER
  1.5977 +** <li>  SQLITE_MUTEX_STATIC_MEM
  1.5978 +** <li>  SQLITE_MUTEX_STATIC_OPEN
  1.5979 +** <li>  SQLITE_MUTEX_STATIC_PRNG
  1.5980 +** <li>  SQLITE_MUTEX_STATIC_LRU
  1.5981 +** <li>  SQLITE_MUTEX_STATIC_PMEM
  1.5982 +** <li>  SQLITE_MUTEX_STATIC_APP1
  1.5983 +** <li>  SQLITE_MUTEX_STATIC_APP2
  1.5984 +** </ul>)^
  1.5985 +**
  1.5986 +** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
  1.5987 +** cause sqlite3_mutex_alloc() to create
  1.5988 +** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
  1.5989 +** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
  1.5990 +** The mutex implementation does not need to make a distinction
  1.5991 +** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
  1.5992 +** not want to.  ^SQLite will only request a recursive mutex in
  1.5993 +** cases where it really needs one.  ^If a faster non-recursive mutex
  1.5994 +** implementation is available on the host platform, the mutex subsystem
  1.5995 +** might return such a mutex in response to SQLITE_MUTEX_FAST.
  1.5996 +**
  1.5997 +** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
  1.5998 +** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
  1.5999 +** a pointer to a static preexisting mutex.  ^Six static mutexes are
  1.6000 +** used by the current version of SQLite.  Future versions of SQLite
  1.6001 +** may add additional static mutexes.  Static mutexes are for internal
  1.6002 +** use by SQLite only.  Applications that use SQLite mutexes should
  1.6003 +** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
  1.6004 +** SQLITE_MUTEX_RECURSIVE.
  1.6005 +**
  1.6006 +** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
  1.6007 +** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
  1.6008 +** returns a different mutex on every call.  ^But for the static
  1.6009 +** mutex types, the same mutex is returned on every call that has
  1.6010 +** the same type number.
  1.6011 +**
  1.6012 +** ^The sqlite3_mutex_free() routine deallocates a previously
  1.6013 +** allocated dynamic mutex.  ^SQLite is careful to deallocate every
  1.6014 +** dynamic mutex that it allocates.  The dynamic mutexes must not be in
  1.6015 +** use when they are deallocated.  Attempting to deallocate a static
  1.6016 +** mutex results in undefined behavior.  ^SQLite never deallocates
  1.6017 +** a static mutex.
  1.6018 +**
  1.6019 +** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
  1.6020 +** to enter a mutex.  ^If another thread is already within the mutex,
  1.6021 +** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
  1.6022 +** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
  1.6023 +** upon successful entry.  ^(Mutexes created using
  1.6024 +** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
  1.6025 +** In such cases the,
  1.6026 +** mutex must be exited an equal number of times before another thread
  1.6027 +** can enter.)^  ^(If the same thread tries to enter any other
  1.6028 +** kind of mutex more than once, the behavior is undefined.
  1.6029 +** SQLite will never exhibit
  1.6030 +** such behavior in its own use of mutexes.)^
  1.6031 +**
  1.6032 +** ^(Some systems (for example, Windows 95) do not support the operation
  1.6033 +** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
  1.6034 +** will always return SQLITE_BUSY.  The SQLite core only ever uses
  1.6035 +** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
  1.6036 +**
  1.6037 +** ^The sqlite3_mutex_leave() routine exits a mutex that was
  1.6038 +** previously entered by the same thread.   ^(The behavior
  1.6039 +** is undefined if the mutex is not currently entered by the
  1.6040 +** calling thread or is not currently allocated.  SQLite will
  1.6041 +** never do either.)^
  1.6042 +**
  1.6043 +** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
  1.6044 +** sqlite3_mutex_leave() is a NULL pointer, then all three routines
  1.6045 +** behave as no-ops.
  1.6046 +**
  1.6047 +** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
  1.6048 +*/
  1.6049 +SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
  1.6050 +SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
  1.6051 +SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
  1.6052 +SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
  1.6053 +SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
  1.6054 +
  1.6055 +/*
  1.6056 +** CAPI3REF: Mutex Methods Object
  1.6057 +**
  1.6058 +** An instance of this structure defines the low-level routines
  1.6059 +** used to allocate and use mutexes.
  1.6060 +**
  1.6061 +** Usually, the default mutex implementations provided by SQLite are
  1.6062 +** sufficient, however the user has the option of substituting a custom
  1.6063 +** implementation for specialized deployments or systems for which SQLite
  1.6064 +** does not provide a suitable implementation. In this case, the user
  1.6065 +** creates and populates an instance of this structure to pass
  1.6066 +** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
  1.6067 +** Additionally, an instance of this structure can be used as an
  1.6068 +** output variable when querying the system for the current mutex
  1.6069 +** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
  1.6070 +**
  1.6071 +** ^The xMutexInit method defined by this structure is invoked as
  1.6072 +** part of system initialization by the sqlite3_initialize() function.
  1.6073 +** ^The xMutexInit routine is called by SQLite exactly once for each
  1.6074 +** effective call to [sqlite3_initialize()].
  1.6075 +**
  1.6076 +** ^The xMutexEnd method defined by this structure is invoked as
  1.6077 +** part of system shutdown by the sqlite3_shutdown() function. The
  1.6078 +** implementation of this method is expected to release all outstanding
  1.6079 +** resources obtained by the mutex methods implementation, especially
  1.6080 +** those obtained by the xMutexInit method.  ^The xMutexEnd()
  1.6081 +** interface is invoked exactly once for each call to [sqlite3_shutdown()].
  1.6082 +**
  1.6083 +** ^(The remaining seven methods defined by this structure (xMutexAlloc,
  1.6084 +** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
  1.6085 +** xMutexNotheld) implement the following interfaces (respectively):
  1.6086 +**
  1.6087 +** <ul>
  1.6088 +**   <li>  [sqlite3_mutex_alloc()] </li>
  1.6089 +**   <li>  [sqlite3_mutex_free()] </li>
  1.6090 +**   <li>  [sqlite3_mutex_enter()] </li>
  1.6091 +**   <li>  [sqlite3_mutex_try()] </li>
  1.6092 +**   <li>  [sqlite3_mutex_leave()] </li>
  1.6093 +**   <li>  [sqlite3_mutex_held()] </li>
  1.6094 +**   <li>  [sqlite3_mutex_notheld()] </li>
  1.6095 +** </ul>)^
  1.6096 +**
  1.6097 +** The only difference is that the public sqlite3_XXX functions enumerated
  1.6098 +** above silently ignore any invocations that pass a NULL pointer instead
  1.6099 +** of a valid mutex handle. The implementations of the methods defined
  1.6100 +** by this structure are not required to handle this case, the results
  1.6101 +** of passing a NULL pointer instead of a valid mutex handle are undefined
  1.6102 +** (i.e. it is acceptable to provide an implementation that segfaults if
  1.6103 +** it is passed a NULL pointer).
  1.6104 +**
  1.6105 +** The xMutexInit() method must be threadsafe.  ^It must be harmless to
  1.6106 +** invoke xMutexInit() multiple times within the same process and without
  1.6107 +** intervening calls to xMutexEnd().  Second and subsequent calls to
  1.6108 +** xMutexInit() must be no-ops.
  1.6109 +**
  1.6110 +** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
  1.6111 +** and its associates).  ^Similarly, xMutexAlloc() must not use SQLite memory
  1.6112 +** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
  1.6113 +** memory allocation for a fast or recursive mutex.
  1.6114 +**
  1.6115 +** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
  1.6116 +** called, but only if the prior call to xMutexInit returned SQLITE_OK.
  1.6117 +** If xMutexInit fails in any way, it is expected to clean up after itself
  1.6118 +** prior to returning.
  1.6119 +*/
  1.6120 +typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
  1.6121 +struct sqlite3_mutex_methods {
  1.6122 +  int (*xMutexInit)(void);
  1.6123 +  int (*xMutexEnd)(void);
  1.6124 +  sqlite3_mutex *(*xMutexAlloc)(int);
  1.6125 +  void (*xMutexFree)(sqlite3_mutex *);
  1.6126 +  void (*xMutexEnter)(sqlite3_mutex *);
  1.6127 +  int (*xMutexTry)(sqlite3_mutex *);
  1.6128 +  void (*xMutexLeave)(sqlite3_mutex *);
  1.6129 +  int (*xMutexHeld)(sqlite3_mutex *);
  1.6130 +  int (*xMutexNotheld)(sqlite3_mutex *);
  1.6131 +};
  1.6132 +
  1.6133 +/*
  1.6134 +** CAPI3REF: Mutex Verification Routines
  1.6135 +**
  1.6136 +** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
  1.6137 +** are intended for use inside assert() statements.  ^The SQLite core
  1.6138 +** never uses these routines except inside an assert() and applications
  1.6139 +** are advised to follow the lead of the core.  ^The SQLite core only
  1.6140 +** provides implementations for these routines when it is compiled
  1.6141 +** with the SQLITE_DEBUG flag.  ^External mutex implementations
  1.6142 +** are only required to provide these routines if SQLITE_DEBUG is
  1.6143 +** defined and if NDEBUG is not defined.
  1.6144 +**
  1.6145 +** ^These routines should return true if the mutex in their argument
  1.6146 +** is held or not held, respectively, by the calling thread.
  1.6147 +**
  1.6148 +** ^The implementation is not required to provide versions of these
  1.6149 +** routines that actually work. If the implementation does not provide working
  1.6150 +** versions of these routines, it should at least provide stubs that always
  1.6151 +** return true so that one does not get spurious assertion failures.
  1.6152 +**
  1.6153 +** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
  1.6154 +** the routine should return 1.   This seems counter-intuitive since
  1.6155 +** clearly the mutex cannot be held if it does not exist.  But
  1.6156 +** the reason the mutex does not exist is because the build is not
  1.6157 +** using mutexes.  And we do not want the assert() containing the
  1.6158 +** call to sqlite3_mutex_held() to fail, so a non-zero return is
  1.6159 +** the appropriate thing to do.  ^The sqlite3_mutex_notheld()
  1.6160 +** interface should also return 1 when given a NULL pointer.
  1.6161 +*/
  1.6162 +#ifndef NDEBUG
  1.6163 +SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
  1.6164 +SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
  1.6165 +#endif
  1.6166 +
  1.6167 +/*
  1.6168 +** CAPI3REF: Mutex Types
  1.6169 +**
  1.6170 +** The [sqlite3_mutex_alloc()] interface takes a single argument
  1.6171 +** which is one of these integer constants.
  1.6172 +**
  1.6173 +** The set of static mutexes may change from one SQLite release to the
  1.6174 +** next.  Applications that override the built-in mutex logic must be
  1.6175 +** prepared to accommodate additional static mutexes.
  1.6176 +*/
  1.6177 +#define SQLITE_MUTEX_FAST             0
  1.6178 +#define SQLITE_MUTEX_RECURSIVE        1
  1.6179 +#define SQLITE_MUTEX_STATIC_MASTER    2
  1.6180 +#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
  1.6181 +#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
  1.6182 +#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
  1.6183 +#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
  1.6184 +#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
  1.6185 +#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
  1.6186 +#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
  1.6187 +#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
  1.6188 +#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
  1.6189 +#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */
  1.6190 +
  1.6191 +/*
  1.6192 +** CAPI3REF: Retrieve the mutex for a database connection
  1.6193 +**
  1.6194 +** ^This interface returns a pointer the [sqlite3_mutex] object that 
  1.6195 +** serializes access to the [database connection] given in the argument
  1.6196 +** when the [threading mode] is Serialized.
  1.6197 +** ^If the [threading mode] is Single-thread or Multi-thread then this
  1.6198 +** routine returns a NULL pointer.
  1.6199 +*/
  1.6200 +SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
  1.6201 +
  1.6202 +/*
  1.6203 +** CAPI3REF: Low-Level Control Of Database Files
  1.6204 +**
  1.6205 +** ^The [sqlite3_file_control()] interface makes a direct call to the
  1.6206 +** xFileControl method for the [sqlite3_io_methods] object associated
  1.6207 +** with a particular database identified by the second argument. ^The
  1.6208 +** name of the database is "main" for the main database or "temp" for the
  1.6209 +** TEMP database, or the name that appears after the AS keyword for
  1.6210 +** databases that are added using the [ATTACH] SQL command.
  1.6211 +** ^A NULL pointer can be used in place of "main" to refer to the
  1.6212 +** main database file.
  1.6213 +** ^The third and fourth parameters to this routine
  1.6214 +** are passed directly through to the second and third parameters of
  1.6215 +** the xFileControl method.  ^The return value of the xFileControl
  1.6216 +** method becomes the return value of this routine.
  1.6217 +**
  1.6218 +** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
  1.6219 +** a pointer to the underlying [sqlite3_file] object to be written into
  1.6220 +** the space pointed to by the 4th parameter.  ^The SQLITE_FCNTL_FILE_POINTER
  1.6221 +** case is a short-circuit path which does not actually invoke the
  1.6222 +** underlying sqlite3_io_methods.xFileControl method.
  1.6223 +**
  1.6224 +** ^If the second parameter (zDbName) does not match the name of any
  1.6225 +** open database file, then SQLITE_ERROR is returned.  ^This error
  1.6226 +** code is not remembered and will not be recalled by [sqlite3_errcode()]
  1.6227 +** or [sqlite3_errmsg()].  The underlying xFileControl method might
  1.6228 +** also return SQLITE_ERROR.  There is no way to distinguish between
  1.6229 +** an incorrect zDbName and an SQLITE_ERROR return from the underlying
  1.6230 +** xFileControl method.
  1.6231 +**
  1.6232 +** See also: [SQLITE_FCNTL_LOCKSTATE]
  1.6233 +*/
  1.6234 +SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
  1.6235 +
  1.6236 +/*
  1.6237 +** CAPI3REF: Testing Interface
  1.6238 +**
  1.6239 +** ^The sqlite3_test_control() interface is used to read out internal
  1.6240 +** state of SQLite and to inject faults into SQLite for testing
  1.6241 +** purposes.  ^The first parameter is an operation code that determines
  1.6242 +** the number, meaning, and operation of all subsequent parameters.
  1.6243 +**
  1.6244 +** This interface is not for use by applications.  It exists solely
  1.6245 +** for verifying the correct operation of the SQLite library.  Depending
  1.6246 +** on how the SQLite library is compiled, this interface might not exist.
  1.6247 +**
  1.6248 +** The details of the operation codes, their meanings, the parameters
  1.6249 +** they take, and what they do are all subject to change without notice.
  1.6250 +** Unlike most of the SQLite API, this function is not guaranteed to
  1.6251 +** operate consistently from one release to the next.
  1.6252 +*/
  1.6253 +SQLITE_API int sqlite3_test_control(int op, ...);
  1.6254 +
  1.6255 +/*
  1.6256 +** CAPI3REF: Testing Interface Operation Codes
  1.6257 +**
  1.6258 +** These constants are the valid operation code parameters used
  1.6259 +** as the first argument to [sqlite3_test_control()].
  1.6260 +**
  1.6261 +** These parameters and their meanings are subject to change
  1.6262 +** without notice.  These values are for testing purposes only.
  1.6263 +** Applications should not use any of these parameters or the
  1.6264 +** [sqlite3_test_control()] interface.
  1.6265 +*/
  1.6266 +#define SQLITE_TESTCTRL_FIRST                    5
  1.6267 +#define SQLITE_TESTCTRL_PRNG_SAVE                5
  1.6268 +#define SQLITE_TESTCTRL_PRNG_RESTORE             6
  1.6269 +#define SQLITE_TESTCTRL_PRNG_RESET               7
  1.6270 +#define SQLITE_TESTCTRL_BITVEC_TEST              8
  1.6271 +#define SQLITE_TESTCTRL_FAULT_INSTALL            9
  1.6272 +#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
  1.6273 +#define SQLITE_TESTCTRL_PENDING_BYTE            11
  1.6274 +#define SQLITE_TESTCTRL_ASSERT                  12
  1.6275 +#define SQLITE_TESTCTRL_ALWAYS                  13
  1.6276 +#define SQLITE_TESTCTRL_RESERVE                 14
  1.6277 +#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
  1.6278 +#define SQLITE_TESTCTRL_ISKEYWORD               16
  1.6279 +#define SQLITE_TESTCTRL_SCRATCHMALLOC           17
  1.6280 +#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
  1.6281 +#define SQLITE_TESTCTRL_EXPLAIN_STMT            19
  1.6282 +#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
  1.6283 +#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
  1.6284 +#define SQLITE_TESTCTRL_BYTEORDER               22
  1.6285 +#define SQLITE_TESTCTRL_ISINIT                  23
  1.6286 +#define SQLITE_TESTCTRL_LAST                    23
  1.6287 +
  1.6288 +/*
  1.6289 +** CAPI3REF: SQLite Runtime Status
  1.6290 +**
  1.6291 +** ^This interface is used to retrieve runtime status information
  1.6292 +** about the performance of SQLite, and optionally to reset various
  1.6293 +** highwater marks.  ^The first argument is an integer code for
  1.6294 +** the specific parameter to measure.  ^(Recognized integer codes
  1.6295 +** are of the form [status parameters | SQLITE_STATUS_...].)^
  1.6296 +** ^The current value of the parameter is returned into *pCurrent.
  1.6297 +** ^The highest recorded value is returned in *pHighwater.  ^If the
  1.6298 +** resetFlag is true, then the highest record value is reset after
  1.6299 +** *pHighwater is written.  ^(Some parameters do not record the highest
  1.6300 +** value.  For those parameters
  1.6301 +** nothing is written into *pHighwater and the resetFlag is ignored.)^
  1.6302 +** ^(Other parameters record only the highwater mark and not the current
  1.6303 +** value.  For these latter parameters nothing is written into *pCurrent.)^
  1.6304 +**
  1.6305 +** ^The sqlite3_status() routine returns SQLITE_OK on success and a
  1.6306 +** non-zero [error code] on failure.
  1.6307 +**
  1.6308 +** This routine is threadsafe but is not atomic.  This routine can be
  1.6309 +** called while other threads are running the same or different SQLite
  1.6310 +** interfaces.  However the values returned in *pCurrent and
  1.6311 +** *pHighwater reflect the status of SQLite at different points in time
  1.6312 +** and it is possible that another thread might change the parameter
  1.6313 +** in between the times when *pCurrent and *pHighwater are written.
  1.6314 +**
  1.6315 +** See also: [sqlite3_db_status()]
  1.6316 +*/
  1.6317 +SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
  1.6318 +
  1.6319 +
  1.6320 +/*
  1.6321 +** CAPI3REF: Status Parameters
  1.6322 +** KEYWORDS: {status parameters}
  1.6323 +**
  1.6324 +** These integer constants designate various run-time status parameters
  1.6325 +** that can be returned by [sqlite3_status()].
  1.6326 +**
  1.6327 +** <dl>
  1.6328 +** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
  1.6329 +** <dd>This parameter is the current amount of memory checked out
  1.6330 +** using [sqlite3_malloc()], either directly or indirectly.  The
  1.6331 +** figure includes calls made to [sqlite3_malloc()] by the application
  1.6332 +** and internal memory usage by the SQLite library.  Scratch memory
  1.6333 +** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
  1.6334 +** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
  1.6335 +** this parameter.  The amount returned is the sum of the allocation
  1.6336 +** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
  1.6337 +**
  1.6338 +** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
  1.6339 +** <dd>This parameter records the largest memory allocation request
  1.6340 +** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
  1.6341 +** internal equivalents).  Only the value returned in the
  1.6342 +** *pHighwater parameter to [sqlite3_status()] is of interest.  
  1.6343 +** The value written into the *pCurrent parameter is undefined.</dd>)^
  1.6344 +**
  1.6345 +** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
  1.6346 +** <dd>This parameter records the number of separate memory allocations
  1.6347 +** currently checked out.</dd>)^
  1.6348 +**
  1.6349 +** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
  1.6350 +** <dd>This parameter returns the number of pages used out of the
  1.6351 +** [pagecache memory allocator] that was configured using 
  1.6352 +** [SQLITE_CONFIG_PAGECACHE].  The
  1.6353 +** value returned is in pages, not in bytes.</dd>)^
  1.6354 +**
  1.6355 +** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 
  1.6356 +** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
  1.6357 +** <dd>This parameter returns the number of bytes of page cache
  1.6358 +** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
  1.6359 +** buffer and where forced to overflow to [sqlite3_malloc()].  The
  1.6360 +** returned value includes allocations that overflowed because they
  1.6361 +** where too large (they were larger than the "sz" parameter to
  1.6362 +** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
  1.6363 +** no space was left in the page cache.</dd>)^
  1.6364 +**
  1.6365 +** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
  1.6366 +** <dd>This parameter records the largest memory allocation request
  1.6367 +** handed to [pagecache memory allocator].  Only the value returned in the
  1.6368 +** *pHighwater parameter to [sqlite3_status()] is of interest.  
  1.6369 +** The value written into the *pCurrent parameter is undefined.</dd>)^
  1.6370 +**
  1.6371 +** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
  1.6372 +** <dd>This parameter returns the number of allocations used out of the
  1.6373 +** [scratch memory allocator] configured using
  1.6374 +** [SQLITE_CONFIG_SCRATCH].  The value returned is in allocations, not
  1.6375 +** in bytes.  Since a single thread may only have one scratch allocation
  1.6376 +** outstanding at time, this parameter also reports the number of threads
  1.6377 +** using scratch memory at the same time.</dd>)^
  1.6378 +**
  1.6379 +** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
  1.6380 +** <dd>This parameter returns the number of bytes of scratch memory
  1.6381 +** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
  1.6382 +** buffer and where forced to overflow to [sqlite3_malloc()].  The values
  1.6383 +** returned include overflows because the requested allocation was too
  1.6384 +** larger (that is, because the requested allocation was larger than the
  1.6385 +** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
  1.6386 +** slots were available.
  1.6387 +** </dd>)^
  1.6388 +**
  1.6389 +** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
  1.6390 +** <dd>This parameter records the largest memory allocation request
  1.6391 +** handed to [scratch memory allocator].  Only the value returned in the
  1.6392 +** *pHighwater parameter to [sqlite3_status()] is of interest.  
  1.6393 +** The value written into the *pCurrent parameter is undefined.</dd>)^
  1.6394 +**
  1.6395 +** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
  1.6396 +** <dd>This parameter records the deepest parser stack.  It is only
  1.6397 +** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
  1.6398 +** </dl>
  1.6399 +**
  1.6400 +** New status parameters may be added from time to time.
  1.6401 +*/
  1.6402 +#define SQLITE_STATUS_MEMORY_USED          0
  1.6403 +#define SQLITE_STATUS_PAGECACHE_USED       1
  1.6404 +#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
  1.6405 +#define SQLITE_STATUS_SCRATCH_USED         3
  1.6406 +#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
  1.6407 +#define SQLITE_STATUS_MALLOC_SIZE          5
  1.6408 +#define SQLITE_STATUS_PARSER_STACK         6
  1.6409 +#define SQLITE_STATUS_PAGECACHE_SIZE       7
  1.6410 +#define SQLITE_STATUS_SCRATCH_SIZE         8
  1.6411 +#define SQLITE_STATUS_MALLOC_COUNT         9
  1.6412 +
  1.6413 +/*
  1.6414 +** CAPI3REF: Database Connection Status
  1.6415 +**
  1.6416 +** ^This interface is used to retrieve runtime status information 
  1.6417 +** about a single [database connection].  ^The first argument is the
  1.6418 +** database connection object to be interrogated.  ^The second argument
  1.6419 +** is an integer constant, taken from the set of
  1.6420 +** [SQLITE_DBSTATUS options], that
  1.6421 +** determines the parameter to interrogate.  The set of 
  1.6422 +** [SQLITE_DBSTATUS options] is likely
  1.6423 +** to grow in future releases of SQLite.
  1.6424 +**
  1.6425 +** ^The current value of the requested parameter is written into *pCur
  1.6426 +** and the highest instantaneous value is written into *pHiwtr.  ^If
  1.6427 +** the resetFlg is true, then the highest instantaneous value is
  1.6428 +** reset back down to the current value.
  1.6429 +**
  1.6430 +** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
  1.6431 +** non-zero [error code] on failure.
  1.6432 +**
  1.6433 +** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
  1.6434 +*/
  1.6435 +SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
  1.6436 +
  1.6437 +/*
  1.6438 +** CAPI3REF: Status Parameters for database connections
  1.6439 +** KEYWORDS: {SQLITE_DBSTATUS options}
  1.6440 +**
  1.6441 +** These constants are the available integer "verbs" that can be passed as
  1.6442 +** the second argument to the [sqlite3_db_status()] interface.
  1.6443 +**
  1.6444 +** New verbs may be added in future releases of SQLite. Existing verbs
  1.6445 +** might be discontinued. Applications should check the return code from
  1.6446 +** [sqlite3_db_status()] to make sure that the call worked.
  1.6447 +** The [sqlite3_db_status()] interface will return a non-zero error code
  1.6448 +** if a discontinued or unsupported verb is invoked.
  1.6449 +**
  1.6450 +** <dl>
  1.6451 +** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
  1.6452 +** <dd>This parameter returns the number of lookaside memory slots currently
  1.6453 +** checked out.</dd>)^
  1.6454 +**
  1.6455 +** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
  1.6456 +** <dd>This parameter returns the number malloc attempts that were 
  1.6457 +** satisfied using lookaside memory. Only the high-water value is meaningful;
  1.6458 +** the current value is always zero.)^
  1.6459 +**
  1.6460 +** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
  1.6461 +** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
  1.6462 +** <dd>This parameter returns the number malloc attempts that might have
  1.6463 +** been satisfied using lookaside memory but failed due to the amount of
  1.6464 +** memory requested being larger than the lookaside slot size.
  1.6465 +** Only the high-water value is meaningful;
  1.6466 +** the current value is always zero.)^
  1.6467 +**
  1.6468 +** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
  1.6469 +** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
  1.6470 +** <dd>This parameter returns the number malloc attempts that might have
  1.6471 +** been satisfied using lookaside memory but failed due to all lookaside
  1.6472 +** memory already being in use.
  1.6473 +** Only the high-water value is meaningful;
  1.6474 +** the current value is always zero.)^
  1.6475 +**
  1.6476 +** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
  1.6477 +** <dd>This parameter returns the approximate number of of bytes of heap
  1.6478 +** memory used by all pager caches associated with the database connection.)^
  1.6479 +** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
  1.6480 +**
  1.6481 +** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
  1.6482 +** <dd>This parameter returns the approximate number of of bytes of heap
  1.6483 +** memory used to store the schema for all databases associated
  1.6484 +** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 
  1.6485 +** ^The full amount of memory used by the schemas is reported, even if the
  1.6486 +** schema memory is shared with other database connections due to
  1.6487 +** [shared cache mode] being enabled.
  1.6488 +** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
  1.6489 +**
  1.6490 +** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
  1.6491 +** <dd>This parameter returns the approximate number of of bytes of heap
  1.6492 +** and lookaside memory used by all prepared statements associated with
  1.6493 +** the database connection.)^
  1.6494 +** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
  1.6495 +** </dd>
  1.6496 +**
  1.6497 +** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
  1.6498 +** <dd>This parameter returns the number of pager cache hits that have
  1.6499 +** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 
  1.6500 +** is always 0.
  1.6501 +** </dd>
  1.6502 +**
  1.6503 +** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
  1.6504 +** <dd>This parameter returns the number of pager cache misses that have
  1.6505 +** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 
  1.6506 +** is always 0.
  1.6507 +** </dd>
  1.6508 +**
  1.6509 +** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
  1.6510 +** <dd>This parameter returns the number of dirty cache entries that have
  1.6511 +** been written to disk. Specifically, the number of pages written to the
  1.6512 +** wal file in wal mode databases, or the number of pages written to the
  1.6513 +** database file in rollback mode databases. Any pages written as part of
  1.6514 +** transaction rollback or database recovery operations are not included.
  1.6515 +** If an IO or other error occurs while writing a page to disk, the effect
  1.6516 +** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
  1.6517 +** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
  1.6518 +** </dd>
  1.6519 +**
  1.6520 +** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
  1.6521 +** <dd>This parameter returns zero for the current value if and only if
  1.6522 +** all foreign key constraints (deferred or immediate) have been
  1.6523 +** resolved.)^  ^The highwater mark is always 0.
  1.6524 +** </dd>
  1.6525 +** </dl>
  1.6526 +*/
  1.6527 +#define SQLITE_DBSTATUS_LOOKASIDE_USED       0
  1.6528 +#define SQLITE_DBSTATUS_CACHE_USED           1
  1.6529 +#define SQLITE_DBSTATUS_SCHEMA_USED          2
  1.6530 +#define SQLITE_DBSTATUS_STMT_USED            3
  1.6531 +#define SQLITE_DBSTATUS_LOOKASIDE_HIT        4
  1.6532 +#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE  5
  1.6533 +#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL  6
  1.6534 +#define SQLITE_DBSTATUS_CACHE_HIT            7
  1.6535 +#define SQLITE_DBSTATUS_CACHE_MISS           8
  1.6536 +#define SQLITE_DBSTATUS_CACHE_WRITE          9
  1.6537 +#define SQLITE_DBSTATUS_DEFERRED_FKS        10
  1.6538 +#define SQLITE_DBSTATUS_MAX                 10   /* Largest defined DBSTATUS */
  1.6539 +
  1.6540 +
  1.6541 +/*
  1.6542 +** CAPI3REF: Prepared Statement Status
  1.6543 +**
  1.6544 +** ^(Each prepared statement maintains various
  1.6545 +** [SQLITE_STMTSTATUS counters] that measure the number
  1.6546 +** of times it has performed specific operations.)^  These counters can
  1.6547 +** be used to monitor the performance characteristics of the prepared
  1.6548 +** statements.  For example, if the number of table steps greatly exceeds
  1.6549 +** the number of table searches or result rows, that would tend to indicate
  1.6550 +** that the prepared statement is using a full table scan rather than
  1.6551 +** an index.  
  1.6552 +**
  1.6553 +** ^(This interface is used to retrieve and reset counter values from
  1.6554 +** a [prepared statement].  The first argument is the prepared statement
  1.6555 +** object to be interrogated.  The second argument
  1.6556 +** is an integer code for a specific [SQLITE_STMTSTATUS counter]
  1.6557 +** to be interrogated.)^
  1.6558 +** ^The current value of the requested counter is returned.
  1.6559 +** ^If the resetFlg is true, then the counter is reset to zero after this
  1.6560 +** interface call returns.
  1.6561 +**
  1.6562 +** See also: [sqlite3_status()] and [sqlite3_db_status()].
  1.6563 +*/
  1.6564 +SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
  1.6565 +
  1.6566 +/*
  1.6567 +** CAPI3REF: Status Parameters for prepared statements
  1.6568 +** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
  1.6569 +**
  1.6570 +** These preprocessor macros define integer codes that name counter
  1.6571 +** values associated with the [sqlite3_stmt_status()] interface.
  1.6572 +** The meanings of the various counters are as follows:
  1.6573 +**
  1.6574 +** <dl>
  1.6575 +** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
  1.6576 +** <dd>^This is the number of times that SQLite has stepped forward in
  1.6577 +** a table as part of a full table scan.  Large numbers for this counter
  1.6578 +** may indicate opportunities for performance improvement through 
  1.6579 +** careful use of indices.</dd>
  1.6580 +**
  1.6581 +** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
  1.6582 +** <dd>^This is the number of sort operations that have occurred.
  1.6583 +** A non-zero value in this counter may indicate an opportunity to
  1.6584 +** improvement performance through careful use of indices.</dd>
  1.6585 +**
  1.6586 +** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
  1.6587 +** <dd>^This is the number of rows inserted into transient indices that
  1.6588 +** were created automatically in order to help joins run faster.
  1.6589 +** A non-zero value in this counter may indicate an opportunity to
  1.6590 +** improvement performance by adding permanent indices that do not
  1.6591 +** need to be reinitialized each time the statement is run.</dd>
  1.6592 +**
  1.6593 +** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
  1.6594 +** <dd>^This is the number of virtual machine operations executed
  1.6595 +** by the prepared statement if that number is less than or equal
  1.6596 +** to 2147483647.  The number of virtual machine operations can be 
  1.6597 +** used as a proxy for the total work done by the prepared statement.
  1.6598 +** If the number of virtual machine operations exceeds 2147483647
  1.6599 +** then the value returned by this statement status code is undefined.
  1.6600 +** </dd>
  1.6601 +** </dl>
  1.6602 +*/
  1.6603 +#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
  1.6604 +#define SQLITE_STMTSTATUS_SORT              2
  1.6605 +#define SQLITE_STMTSTATUS_AUTOINDEX         3
  1.6606 +#define SQLITE_STMTSTATUS_VM_STEP           4
  1.6607 +
  1.6608 +/*
  1.6609 +** CAPI3REF: Custom Page Cache Object
  1.6610 +**
  1.6611 +** The sqlite3_pcache type is opaque.  It is implemented by
  1.6612 +** the pluggable module.  The SQLite core has no knowledge of
  1.6613 +** its size or internal structure and never deals with the
  1.6614 +** sqlite3_pcache object except by holding and passing pointers
  1.6615 +** to the object.
  1.6616 +**
  1.6617 +** See [sqlite3_pcache_methods2] for additional information.
  1.6618 +*/
  1.6619 +typedef struct sqlite3_pcache sqlite3_pcache;
  1.6620 +
  1.6621 +/*
  1.6622 +** CAPI3REF: Custom Page Cache Object
  1.6623 +**
  1.6624 +** The sqlite3_pcache_page object represents a single page in the
  1.6625 +** page cache.  The page cache will allocate instances of this
  1.6626 +** object.  Various methods of the page cache use pointers to instances
  1.6627 +** of this object as parameters or as their return value.
  1.6628 +**
  1.6629 +** See [sqlite3_pcache_methods2] for additional information.
  1.6630 +*/
  1.6631 +typedef struct sqlite3_pcache_page sqlite3_pcache_page;
  1.6632 +struct sqlite3_pcache_page {
  1.6633 +  void *pBuf;        /* The content of the page */
  1.6634 +  void *pExtra;      /* Extra information associated with the page */
  1.6635 +};
  1.6636 +
  1.6637 +/*
  1.6638 +** CAPI3REF: Application Defined Page Cache.
  1.6639 +** KEYWORDS: {page cache}
  1.6640 +**
  1.6641 +** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
  1.6642 +** register an alternative page cache implementation by passing in an 
  1.6643 +** instance of the sqlite3_pcache_methods2 structure.)^
  1.6644 +** In many applications, most of the heap memory allocated by 
  1.6645 +** SQLite is used for the page cache.
  1.6646 +** By implementing a 
  1.6647 +** custom page cache using this API, an application can better control
  1.6648 +** the amount of memory consumed by SQLite, the way in which 
  1.6649 +** that memory is allocated and released, and the policies used to 
  1.6650 +** determine exactly which parts of a database file are cached and for 
  1.6651 +** how long.
  1.6652 +**
  1.6653 +** The alternative page cache mechanism is an
  1.6654 +** extreme measure that is only needed by the most demanding applications.
  1.6655 +** The built-in page cache is recommended for most uses.
  1.6656 +**
  1.6657 +** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
  1.6658 +** internal buffer by SQLite within the call to [sqlite3_config].  Hence
  1.6659 +** the application may discard the parameter after the call to
  1.6660 +** [sqlite3_config()] returns.)^
  1.6661 +**
  1.6662 +** [[the xInit() page cache method]]
  1.6663 +** ^(The xInit() method is called once for each effective 
  1.6664 +** call to [sqlite3_initialize()])^
  1.6665 +** (usually only once during the lifetime of the process). ^(The xInit()
  1.6666 +** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
  1.6667 +** The intent of the xInit() method is to set up global data structures 
  1.6668 +** required by the custom page cache implementation. 
  1.6669 +** ^(If the xInit() method is NULL, then the 
  1.6670 +** built-in default page cache is used instead of the application defined
  1.6671 +** page cache.)^
  1.6672 +**
  1.6673 +** [[the xShutdown() page cache method]]
  1.6674 +** ^The xShutdown() method is called by [sqlite3_shutdown()].
  1.6675 +** It can be used to clean up 
  1.6676 +** any outstanding resources before process shutdown, if required.
  1.6677 +** ^The xShutdown() method may be NULL.
  1.6678 +**
  1.6679 +** ^SQLite automatically serializes calls to the xInit method,
  1.6680 +** so the xInit method need not be threadsafe.  ^The
  1.6681 +** xShutdown method is only called from [sqlite3_shutdown()] so it does
  1.6682 +** not need to be threadsafe either.  All other methods must be threadsafe
  1.6683 +** in multithreaded applications.
  1.6684 +**
  1.6685 +** ^SQLite will never invoke xInit() more than once without an intervening
  1.6686 +** call to xShutdown().
  1.6687 +**
  1.6688 +** [[the xCreate() page cache methods]]
  1.6689 +** ^SQLite invokes the xCreate() method to construct a new cache instance.
  1.6690 +** SQLite will typically create one cache instance for each open database file,
  1.6691 +** though this is not guaranteed. ^The
  1.6692 +** first parameter, szPage, is the size in bytes of the pages that must
  1.6693 +** be allocated by the cache.  ^szPage will always a power of two.  ^The
  1.6694 +** second parameter szExtra is a number of bytes of extra storage 
  1.6695 +** associated with each page cache entry.  ^The szExtra parameter will
  1.6696 +** a number less than 250.  SQLite will use the
  1.6697 +** extra szExtra bytes on each page to store metadata about the underlying
  1.6698 +** database page on disk.  The value passed into szExtra depends
  1.6699 +** on the SQLite version, the target platform, and how SQLite was compiled.
  1.6700 +** ^The third argument to xCreate(), bPurgeable, is true if the cache being
  1.6701 +** created will be used to cache database pages of a file stored on disk, or
  1.6702 +** false if it is used for an in-memory database. The cache implementation
  1.6703 +** does not have to do anything special based with the value of bPurgeable;
  1.6704 +** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
  1.6705 +** never invoke xUnpin() except to deliberately delete a page.
  1.6706 +** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
  1.6707 +** false will always have the "discard" flag set to true.  
  1.6708 +** ^Hence, a cache created with bPurgeable false will
  1.6709 +** never contain any unpinned pages.
  1.6710 +**
  1.6711 +** [[the xCachesize() page cache method]]
  1.6712 +** ^(The xCachesize() method may be called at any time by SQLite to set the
  1.6713 +** suggested maximum cache-size (number of pages stored by) the cache
  1.6714 +** instance passed as the first argument. This is the value configured using
  1.6715 +** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
  1.6716 +** parameter, the implementation is not required to do anything with this
  1.6717 +** value; it is advisory only.
  1.6718 +**
  1.6719 +** [[the xPagecount() page cache methods]]
  1.6720 +** The xPagecount() method must return the number of pages currently
  1.6721 +** stored in the cache, both pinned and unpinned.
  1.6722 +** 
  1.6723 +** [[the xFetch() page cache methods]]
  1.6724 +** The xFetch() method locates a page in the cache and returns a pointer to 
  1.6725 +** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
  1.6726 +** The pBuf element of the returned sqlite3_pcache_page object will be a
  1.6727 +** pointer to a buffer of szPage bytes used to store the content of a 
  1.6728 +** single database page.  The pExtra element of sqlite3_pcache_page will be
  1.6729 +** a pointer to the szExtra bytes of extra storage that SQLite has requested
  1.6730 +** for each entry in the page cache.
  1.6731 +**
  1.6732 +** The page to be fetched is determined by the key. ^The minimum key value
  1.6733 +** is 1.  After it has been retrieved using xFetch, the page is considered
  1.6734 +** to be "pinned".
  1.6735 +**
  1.6736 +** If the requested page is already in the page cache, then the page cache
  1.6737 +** implementation must return a pointer to the page buffer with its content
  1.6738 +** intact.  If the requested page is not already in the cache, then the
  1.6739 +** cache implementation should use the value of the createFlag
  1.6740 +** parameter to help it determined what action to take:
  1.6741 +**
  1.6742 +** <table border=1 width=85% align=center>
  1.6743 +** <tr><th> createFlag <th> Behavior when page is not already in cache
  1.6744 +** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
  1.6745 +** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
  1.6746 +**                 Otherwise return NULL.
  1.6747 +** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
  1.6748 +**                 NULL if allocating a new page is effectively impossible.
  1.6749 +** </table>
  1.6750 +**
  1.6751 +** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
  1.6752 +** will only use a createFlag of 2 after a prior call with a createFlag of 1
  1.6753 +** failed.)^  In between the to xFetch() calls, SQLite may
  1.6754 +** attempt to unpin one or more cache pages by spilling the content of
  1.6755 +** pinned pages to disk and synching the operating system disk cache.
  1.6756 +**
  1.6757 +** [[the xUnpin() page cache method]]
  1.6758 +** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
  1.6759 +** as its second argument.  If the third parameter, discard, is non-zero,
  1.6760 +** then the page must be evicted from the cache.
  1.6761 +** ^If the discard parameter is
  1.6762 +** zero, then the page may be discarded or retained at the discretion of
  1.6763 +** page cache implementation. ^The page cache implementation
  1.6764 +** may choose to evict unpinned pages at any time.
  1.6765 +**
  1.6766 +** The cache must not perform any reference counting. A single 
  1.6767 +** call to xUnpin() unpins the page regardless of the number of prior calls 
  1.6768 +** to xFetch().
  1.6769 +**
  1.6770 +** [[the xRekey() page cache methods]]
  1.6771 +** The xRekey() method is used to change the key value associated with the
  1.6772 +** page passed as the second argument. If the cache
  1.6773 +** previously contains an entry associated with newKey, it must be
  1.6774 +** discarded. ^Any prior cache entry associated with newKey is guaranteed not
  1.6775 +** to be pinned.
  1.6776 +**
  1.6777 +** When SQLite calls the xTruncate() method, the cache must discard all
  1.6778 +** existing cache entries with page numbers (keys) greater than or equal
  1.6779 +** to the value of the iLimit parameter passed to xTruncate(). If any
  1.6780 +** of these pages are pinned, they are implicitly unpinned, meaning that
  1.6781 +** they can be safely discarded.
  1.6782 +**
  1.6783 +** [[the xDestroy() page cache method]]
  1.6784 +** ^The xDestroy() method is used to delete a cache allocated by xCreate().
  1.6785 +** All resources associated with the specified cache should be freed. ^After
  1.6786 +** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
  1.6787 +** handle invalid, and will not use it with any other sqlite3_pcache_methods2
  1.6788 +** functions.
  1.6789 +**
  1.6790 +** [[the xShrink() page cache method]]
  1.6791 +** ^SQLite invokes the xShrink() method when it wants the page cache to
  1.6792 +** free up as much of heap memory as possible.  The page cache implementation
  1.6793 +** is not obligated to free any memory, but well-behaved implementations should
  1.6794 +** do their best.
  1.6795 +*/
  1.6796 +typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
  1.6797 +struct sqlite3_pcache_methods2 {
  1.6798 +  int iVersion;
  1.6799 +  void *pArg;
  1.6800 +  int (*xInit)(void*);
  1.6801 +  void (*xShutdown)(void*);
  1.6802 +  sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
  1.6803 +  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
  1.6804 +  int (*xPagecount)(sqlite3_pcache*);
  1.6805 +  sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
  1.6806 +  void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
  1.6807 +  void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 
  1.6808 +      unsigned oldKey, unsigned newKey);
  1.6809 +  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
  1.6810 +  void (*xDestroy)(sqlite3_pcache*);
  1.6811 +  void (*xShrink)(sqlite3_pcache*);
  1.6812 +};
  1.6813 +
  1.6814 +/*
  1.6815 +** This is the obsolete pcache_methods object that has now been replaced
  1.6816 +** by sqlite3_pcache_methods2.  This object is not used by SQLite.  It is
  1.6817 +** retained in the header file for backwards compatibility only.
  1.6818 +*/
  1.6819 +typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
  1.6820 +struct sqlite3_pcache_methods {
  1.6821 +  void *pArg;
  1.6822 +  int (*xInit)(void*);
  1.6823 +  void (*xShutdown)(void*);
  1.6824 +  sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
  1.6825 +  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
  1.6826 +  int (*xPagecount)(sqlite3_pcache*);
  1.6827 +  void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
  1.6828 +  void (*xUnpin)(sqlite3_pcache*, void*, int discard);
  1.6829 +  void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
  1.6830 +  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
  1.6831 +  void (*xDestroy)(sqlite3_pcache*);
  1.6832 +};
  1.6833 +
  1.6834 +
  1.6835 +/*
  1.6836 +** CAPI3REF: Online Backup Object
  1.6837 +**
  1.6838 +** The sqlite3_backup object records state information about an ongoing
  1.6839 +** online backup operation.  ^The sqlite3_backup object is created by
  1.6840 +** a call to [sqlite3_backup_init()] and is destroyed by a call to
  1.6841 +** [sqlite3_backup_finish()].
  1.6842 +**
  1.6843 +** See Also: [Using the SQLite Online Backup API]
  1.6844 +*/
  1.6845 +typedef struct sqlite3_backup sqlite3_backup;
  1.6846 +
  1.6847 +/*
  1.6848 +** CAPI3REF: Online Backup API.
  1.6849 +**
  1.6850 +** The backup API copies the content of one database into another.
  1.6851 +** It is useful either for creating backups of databases or
  1.6852 +** for copying in-memory databases to or from persistent files. 
  1.6853 +**
  1.6854 +** See Also: [Using the SQLite Online Backup API]
  1.6855 +**
  1.6856 +** ^SQLite holds a write transaction open on the destination database file
  1.6857 +** for the duration of the backup operation.
  1.6858 +** ^The source database is read-locked only while it is being read;
  1.6859 +** it is not locked continuously for the entire backup operation.
  1.6860 +** ^Thus, the backup may be performed on a live source database without
  1.6861 +** preventing other database connections from
  1.6862 +** reading or writing to the source database while the backup is underway.
  1.6863 +** 
  1.6864 +** ^(To perform a backup operation: 
  1.6865 +**   <ol>
  1.6866 +**     <li><b>sqlite3_backup_init()</b> is called once to initialize the
  1.6867 +**         backup, 
  1.6868 +**     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 
  1.6869 +**         the data between the two databases, and finally
  1.6870 +**     <li><b>sqlite3_backup_finish()</b> is called to release all resources 
  1.6871 +**         associated with the backup operation. 
  1.6872 +**   </ol>)^
  1.6873 +** There should be exactly one call to sqlite3_backup_finish() for each
  1.6874 +** successful call to sqlite3_backup_init().
  1.6875 +**
  1.6876 +** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
  1.6877 +**
  1.6878 +** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 
  1.6879 +** [database connection] associated with the destination database 
  1.6880 +** and the database name, respectively.
  1.6881 +** ^The database name is "main" for the main database, "temp" for the
  1.6882 +** temporary database, or the name specified after the AS keyword in
  1.6883 +** an [ATTACH] statement for an attached database.
  1.6884 +** ^The S and M arguments passed to 
  1.6885 +** sqlite3_backup_init(D,N,S,M) identify the [database connection]
  1.6886 +** and database name of the source database, respectively.
  1.6887 +** ^The source and destination [database connections] (parameters S and D)
  1.6888 +** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
  1.6889 +** an error.
  1.6890 +**
  1.6891 +** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
  1.6892 +** returned and an error code and error message are stored in the
  1.6893 +** destination [database connection] D.
  1.6894 +** ^The error code and message for the failed call to sqlite3_backup_init()
  1.6895 +** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
  1.6896 +** [sqlite3_errmsg16()] functions.
  1.6897 +** ^A successful call to sqlite3_backup_init() returns a pointer to an
  1.6898 +** [sqlite3_backup] object.
  1.6899 +** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
  1.6900 +** sqlite3_backup_finish() functions to perform the specified backup 
  1.6901 +** operation.
  1.6902 +**
  1.6903 +** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
  1.6904 +**
  1.6905 +** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 
  1.6906 +** the source and destination databases specified by [sqlite3_backup] object B.
  1.6907 +** ^If N is negative, all remaining source pages are copied. 
  1.6908 +** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
  1.6909 +** are still more pages to be copied, then the function returns [SQLITE_OK].
  1.6910 +** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
  1.6911 +** from source to destination, then it returns [SQLITE_DONE].
  1.6912 +** ^If an error occurs while running sqlite3_backup_step(B,N),
  1.6913 +** then an [error code] is returned. ^As well as [SQLITE_OK] and
  1.6914 +** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
  1.6915 +** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
  1.6916 +** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
  1.6917 +**
  1.6918 +** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
  1.6919 +** <ol>
  1.6920 +** <li> the destination database was opened read-only, or
  1.6921 +** <li> the destination database is using write-ahead-log journaling
  1.6922 +** and the destination and source page sizes differ, or
  1.6923 +** <li> the destination database is an in-memory database and the
  1.6924 +** destination and source page sizes differ.
  1.6925 +** </ol>)^
  1.6926 +**
  1.6927 +** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
  1.6928 +** the [sqlite3_busy_handler | busy-handler function]
  1.6929 +** is invoked (if one is specified). ^If the 
  1.6930 +** busy-handler returns non-zero before the lock is available, then 
  1.6931 +** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
  1.6932 +** sqlite3_backup_step() can be retried later. ^If the source
  1.6933 +** [database connection]
  1.6934 +** is being used to write to the source database when sqlite3_backup_step()
  1.6935 +** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
  1.6936 +** case the call to sqlite3_backup_step() can be retried later on. ^(If
  1.6937 +** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
  1.6938 +** [SQLITE_READONLY] is returned, then 
  1.6939 +** there is no point in retrying the call to sqlite3_backup_step(). These 
  1.6940 +** errors are considered fatal.)^  The application must accept 
  1.6941 +** that the backup operation has failed and pass the backup operation handle 
  1.6942 +** to the sqlite3_backup_finish() to release associated resources.
  1.6943 +**
  1.6944 +** ^The first call to sqlite3_backup_step() obtains an exclusive lock
  1.6945 +** on the destination file. ^The exclusive lock is not released until either 
  1.6946 +** sqlite3_backup_finish() is called or the backup operation is complete 
  1.6947 +** and sqlite3_backup_step() returns [SQLITE_DONE].  ^Every call to
  1.6948 +** sqlite3_backup_step() obtains a [shared lock] on the source database that
  1.6949 +** lasts for the duration of the sqlite3_backup_step() call.
  1.6950 +** ^Because the source database is not locked between calls to
  1.6951 +** sqlite3_backup_step(), the source database may be modified mid-way
  1.6952 +** through the backup process.  ^If the source database is modified by an
  1.6953 +** external process or via a database connection other than the one being
  1.6954 +** used by the backup operation, then the backup will be automatically
  1.6955 +** restarted by the next call to sqlite3_backup_step(). ^If the source 
  1.6956 +** database is modified by the using the same database connection as is used
  1.6957 +** by the backup operation, then the backup database is automatically
  1.6958 +** updated at the same time.
  1.6959 +**
  1.6960 +** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
  1.6961 +**
  1.6962 +** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 
  1.6963 +** application wishes to abandon the backup operation, the application
  1.6964 +** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
  1.6965 +** ^The sqlite3_backup_finish() interfaces releases all
  1.6966 +** resources associated with the [sqlite3_backup] object. 
  1.6967 +** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
  1.6968 +** active write-transaction on the destination database is rolled back.
  1.6969 +** The [sqlite3_backup] object is invalid
  1.6970 +** and may not be used following a call to sqlite3_backup_finish().
  1.6971 +**
  1.6972 +** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
  1.6973 +** sqlite3_backup_step() errors occurred, regardless or whether or not
  1.6974 +** sqlite3_backup_step() completed.
  1.6975 +** ^If an out-of-memory condition or IO error occurred during any prior
  1.6976 +** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
  1.6977 +** sqlite3_backup_finish() returns the corresponding [error code].
  1.6978 +**
  1.6979 +** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
  1.6980 +** is not a permanent error and does not affect the return value of
  1.6981 +** sqlite3_backup_finish().
  1.6982 +**
  1.6983 +** [[sqlite3_backup__remaining()]] [[sqlite3_backup_pagecount()]]
  1.6984 +** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
  1.6985 +**
  1.6986 +** ^Each call to sqlite3_backup_step() sets two values inside
  1.6987 +** the [sqlite3_backup] object: the number of pages still to be backed
  1.6988 +** up and the total number of pages in the source database file.
  1.6989 +** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
  1.6990 +** retrieve these two values, respectively.
  1.6991 +**
  1.6992 +** ^The values returned by these functions are only updated by
  1.6993 +** sqlite3_backup_step(). ^If the source database is modified during a backup
  1.6994 +** operation, then the values are not updated to account for any extra
  1.6995 +** pages that need to be updated or the size of the source database file
  1.6996 +** changing.
  1.6997 +**
  1.6998 +** <b>Concurrent Usage of Database Handles</b>
  1.6999 +**
  1.7000 +** ^The source [database connection] may be used by the application for other
  1.7001 +** purposes while a backup operation is underway or being initialized.
  1.7002 +** ^If SQLite is compiled and configured to support threadsafe database
  1.7003 +** connections, then the source database connection may be used concurrently
  1.7004 +** from within other threads.
  1.7005 +**
  1.7006 +** However, the application must guarantee that the destination 
  1.7007 +** [database connection] is not passed to any other API (by any thread) after 
  1.7008 +** sqlite3_backup_init() is called and before the corresponding call to
  1.7009 +** sqlite3_backup_finish().  SQLite does not currently check to see
  1.7010 +** if the application incorrectly accesses the destination [database connection]
  1.7011 +** and so no error code is reported, but the operations may malfunction
  1.7012 +** nevertheless.  Use of the destination database connection while a
  1.7013 +** backup is in progress might also also cause a mutex deadlock.
  1.7014 +**
  1.7015 +** If running in [shared cache mode], the application must
  1.7016 +** guarantee that the shared cache used by the destination database
  1.7017 +** is not accessed while the backup is running. In practice this means
  1.7018 +** that the application must guarantee that the disk file being 
  1.7019 +** backed up to is not accessed by any connection within the process,
  1.7020 +** not just the specific connection that was passed to sqlite3_backup_init().
  1.7021 +**
  1.7022 +** The [sqlite3_backup] object itself is partially threadsafe. Multiple 
  1.7023 +** threads may safely make multiple concurrent calls to sqlite3_backup_step().
  1.7024 +** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
  1.7025 +** APIs are not strictly speaking threadsafe. If they are invoked at the
  1.7026 +** same time as another thread is invoking sqlite3_backup_step() it is
  1.7027 +** possible that they return invalid values.
  1.7028 +*/
  1.7029 +SQLITE_API sqlite3_backup *sqlite3_backup_init(
  1.7030 +  sqlite3 *pDest,                        /* Destination database handle */
  1.7031 +  const char *zDestName,                 /* Destination database name */
  1.7032 +  sqlite3 *pSource,                      /* Source database handle */
  1.7033 +  const char *zSourceName                /* Source database name */
  1.7034 +);
  1.7035 +SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
  1.7036 +SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
  1.7037 +SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
  1.7038 +SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
  1.7039 +
  1.7040 +/*
  1.7041 +** CAPI3REF: Unlock Notification
  1.7042 +**
  1.7043 +** ^When running in shared-cache mode, a database operation may fail with
  1.7044 +** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
  1.7045 +** individual tables within the shared-cache cannot be obtained. See
  1.7046 +** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 
  1.7047 +** ^This API may be used to register a callback that SQLite will invoke 
  1.7048 +** when the connection currently holding the required lock relinquishes it.
  1.7049 +** ^This API is only available if the library was compiled with the
  1.7050 +** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
  1.7051 +**
  1.7052 +** See Also: [Using the SQLite Unlock Notification Feature].
  1.7053 +**
  1.7054 +** ^Shared-cache locks are released when a database connection concludes
  1.7055 +** its current transaction, either by committing it or rolling it back. 
  1.7056 +**
  1.7057 +** ^When a connection (known as the blocked connection) fails to obtain a
  1.7058 +** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
  1.7059 +** identity of the database connection (the blocking connection) that
  1.7060 +** has locked the required resource is stored internally. ^After an 
  1.7061 +** application receives an SQLITE_LOCKED error, it may call the
  1.7062 +** sqlite3_unlock_notify() method with the blocked connection handle as 
  1.7063 +** the first argument to register for a callback that will be invoked
  1.7064 +** when the blocking connections current transaction is concluded. ^The
  1.7065 +** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
  1.7066 +** call that concludes the blocking connections transaction.
  1.7067 +**
  1.7068 +** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
  1.7069 +** there is a chance that the blocking connection will have already
  1.7070 +** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
  1.7071 +** If this happens, then the specified callback is invoked immediately,
  1.7072 +** from within the call to sqlite3_unlock_notify().)^
  1.7073 +**
  1.7074 +** ^If the blocked connection is attempting to obtain a write-lock on a
  1.7075 +** shared-cache table, and more than one other connection currently holds
  1.7076 +** a read-lock on the same table, then SQLite arbitrarily selects one of 
  1.7077 +** the other connections to use as the blocking connection.
  1.7078 +**
  1.7079 +** ^(There may be at most one unlock-notify callback registered by a 
  1.7080 +** blocked connection. If sqlite3_unlock_notify() is called when the
  1.7081 +** blocked connection already has a registered unlock-notify callback,
  1.7082 +** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
  1.7083 +** called with a NULL pointer as its second argument, then any existing
  1.7084 +** unlock-notify callback is canceled. ^The blocked connections 
  1.7085 +** unlock-notify callback may also be canceled by closing the blocked
  1.7086 +** connection using [sqlite3_close()].
  1.7087 +**
  1.7088 +** The unlock-notify callback is not reentrant. If an application invokes
  1.7089 +** any sqlite3_xxx API functions from within an unlock-notify callback, a
  1.7090 +** crash or deadlock may be the result.
  1.7091 +**
  1.7092 +** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
  1.7093 +** returns SQLITE_OK.
  1.7094 +**
  1.7095 +** <b>Callback Invocation Details</b>
  1.7096 +**
  1.7097 +** When an unlock-notify callback is registered, the application provides a 
  1.7098 +** single void* pointer that is passed to the callback when it is invoked.
  1.7099 +** However, the signature of the callback function allows SQLite to pass
  1.7100 +** it an array of void* context pointers. The first argument passed to
  1.7101 +** an unlock-notify callback is a pointer to an array of void* pointers,
  1.7102 +** and the second is the number of entries in the array.
  1.7103 +**
  1.7104 +** When a blocking connections transaction is concluded, there may be
  1.7105 +** more than one blocked connection that has registered for an unlock-notify
  1.7106 +** callback. ^If two or more such blocked connections have specified the
  1.7107 +** same callback function, then instead of invoking the callback function
  1.7108 +** multiple times, it is invoked once with the set of void* context pointers
  1.7109 +** specified by the blocked connections bundled together into an array.
  1.7110 +** This gives the application an opportunity to prioritize any actions 
  1.7111 +** related to the set of unblocked database connections.
  1.7112 +**
  1.7113 +** <b>Deadlock Detection</b>
  1.7114 +**
  1.7115 +** Assuming that after registering for an unlock-notify callback a 
  1.7116 +** database waits for the callback to be issued before taking any further
  1.7117 +** action (a reasonable assumption), then using this API may cause the
  1.7118 +** application to deadlock. For example, if connection X is waiting for
  1.7119 +** connection Y's transaction to be concluded, and similarly connection
  1.7120 +** Y is waiting on connection X's transaction, then neither connection
  1.7121 +** will proceed and the system may remain deadlocked indefinitely.
  1.7122 +**
  1.7123 +** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
  1.7124 +** detection. ^If a given call to sqlite3_unlock_notify() would put the
  1.7125 +** system in a deadlocked state, then SQLITE_LOCKED is returned and no
  1.7126 +** unlock-notify callback is registered. The system is said to be in
  1.7127 +** a deadlocked state if connection A has registered for an unlock-notify
  1.7128 +** callback on the conclusion of connection B's transaction, and connection
  1.7129 +** B has itself registered for an unlock-notify callback when connection
  1.7130 +** A's transaction is concluded. ^Indirect deadlock is also detected, so
  1.7131 +** the system is also considered to be deadlocked if connection B has
  1.7132 +** registered for an unlock-notify callback on the conclusion of connection
  1.7133 +** C's transaction, where connection C is waiting on connection A. ^Any
  1.7134 +** number of levels of indirection are allowed.
  1.7135 +**
  1.7136 +** <b>The "DROP TABLE" Exception</b>
  1.7137 +**
  1.7138 +** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 
  1.7139 +** always appropriate to call sqlite3_unlock_notify(). There is however,
  1.7140 +** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
  1.7141 +** SQLite checks if there are any currently executing SELECT statements
  1.7142 +** that belong to the same connection. If there are, SQLITE_LOCKED is
  1.7143 +** returned. In this case there is no "blocking connection", so invoking
  1.7144 +** sqlite3_unlock_notify() results in the unlock-notify callback being
  1.7145 +** invoked immediately. If the application then re-attempts the "DROP TABLE"
  1.7146 +** or "DROP INDEX" query, an infinite loop might be the result.
  1.7147 +**
  1.7148 +** One way around this problem is to check the extended error code returned
  1.7149 +** by an sqlite3_step() call. ^(If there is a blocking connection, then the
  1.7150 +** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
  1.7151 +** the special "DROP TABLE/INDEX" case, the extended error code is just 
  1.7152 +** SQLITE_LOCKED.)^
  1.7153 +*/
  1.7154 +SQLITE_API int sqlite3_unlock_notify(
  1.7155 +  sqlite3 *pBlocked,                          /* Waiting connection */
  1.7156 +  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
  1.7157 +  void *pNotifyArg                            /* Argument to pass to xNotify */
  1.7158 +);
  1.7159 +
  1.7160 +
  1.7161 +/*
  1.7162 +** CAP