int sqlite3_busy_timeout(sqlite3*, int ms);
This routine sets a busy handler that sleeps for a specified amount of time when a table is locked. The handler will sleep multiple times until at least "ms" milliseconds of sleeping have accumulated. After at least "ms" milliseconds of sleeping, the handler returns 0 which causes sqlite3_step() to return SQLITE_BUSY or SQLITE_IOERR_BLOCKED.
Calling this routine with an argument less than or equal to zero turns off all busy handlers.
There can only be a single busy handler for a particular database connection any any given moment. If another busy handler was defined (using sqlite3_busy_handler()) prior to calling this routine, that other busy handler is cleared.
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