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SQLITE3_WAL_HOOK(3)        Library Functions Manual        SQLITE3_WAL_HOOK(3)

NAME
     sqlite3_wal_hook - write-Ahead log commit hook

SYNOPSIS
     #include <sqlite3.h>

     void *
     sqlite3_wal_hook(sqlite3*, int(*)(void *,sqlite3*,const char*,int),
         void*);

DESCRIPTION
     The sqlite3_wal_hook() function is used to register a callback that is
     invoked each time data is committed to a database in wal mode.

     The callback is invoked by SQLite after the commit has taken place and
     the associated write-lock on the database released, so the implementation
     may read, write or checkpoint the database as required.

     The first parameter passed to the callback function when it is invoked is
     a copy of the third parameter passed to sqlite3_wal_hook() when
     registering the callback.  The second is a copy of the database handle.
     The third parameter is the name of the database that was written to -
     either "main" or the name of an ATTACH-ed database.  The fourth parameter
     is the number of pages currently in the write-ahead log file, including
     those that were just committed.

     The callback function should normally return SQLITE_OK.  If an error code
     is returned, that error will propagate back up through the SQLite code
     base to cause the statement that provoked the callback to report an
     error, though the commit will have still occurred.  If the callback
     returns SQLITE_ROW or SQLITE_DONE, or if it returns a value that does not
     correspond to any valid SQLite error code, the results are undefined.

     A single database handle may have at most a single write-ahead log
     callback registered at one time.  Calling sqlite3_wal_hook() replaces any
     previously registered write-ahead log callback.  The return value is a
     copy of the third parameter from the previous call, if any, or 0.  Note
     that the sqlite3_wal_autocheckpoint() interface and the
     wal_autocheckpoint pragma both invoke sqlite3_wal_hook() and will
     overwrite any prior sqlite3_wal_hook() settings.

IMPLEMENTATION NOTES
     These declarations were extracted from the interface documentation at
     line 9400.

     SQLITE_API void *sqlite3_wal_hook(
       sqlite3*,
       int(*)(void *,sqlite3*,const char*,int),
       void*
     );

SEE ALSO
     sqlite3_wal_autocheckpoint(3), SQLITE_OK(3)

NetBSD 10.99                    August 24, 2023                   NetBSD 10.99