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.Dd December 19, 2018
.Dt SQLITE3_AUTO_EXTENSION 3
.Os
.Sh NAME
.Nm sqlite3_auto_extension
.Nd Automatically Load Statically Linked Extensions
.Sh SYNOPSIS
.Ft int 
.Fo sqlite3_auto_extension
.Fa "void(*xEntryPoint)(void)"
.Fc
.Sh DESCRIPTION
This interface causes the xEntryPoint() function to be invoked for
each new database connection that is created.
The idea here is that xEntryPoint() is the entry point for a statically
linked SQLite extension that is to be automatically
loaded into all new database connections.
.Pp
Even though the function prototype shows that xEntryPoint() takes no
arguments and returns void, SQLite invokes xEntryPoint() with three
arguments and expects an integer result as if the signature of the
entry point where as follows: 
.Bd -ragged
.Bd -literal
   int xEntryPoint(      sqlite3 *db,      const char **pzErrMsg,  
const struct sqlite3_api_routines *pThunk    ); 
.Ed
.Pp
.Ed
.Pp
If the xEntryPoint routine encounters an error, it should make *pzErrMsg
point to an appropriate error message (obtained from sqlite3_mprintf())
and return an appropriate error code.
SQLite ensures that *pzErrMsg is NULL before calling the xEntryPoint().
SQLite will invoke sqlite3_free() on *pzErrMsg after
xEntryPoint() returns.
If any xEntryPoint() returns an error, the sqlite3_open(),
sqlite3_open16(), or sqlite3_open_v2()
call that provoked the xEntryPoint() will fail.
.Pp
Calling sqlite3_auto_extension(X) with an entry point X that is already
on the list of automatic extensions is a harmless no-op.
No entry point will be called more than once for each database connection
that is opened.
.Pp
.Sh SEE ALSO
.Xr sqlite3 3 ,
.Xr sqlite3_cancel_auto_extension 3 ,
.Xr sqlite3_malloc 3 ,
.Xr sqlite3_mprintf 3 ,
.Xr sqlite3_open 3 ,
.Xr sqlite3_reset_auto_extension 3