Alessandro Bonazzi 5c7aa8c1c0 Patch level : 12.0 no-patch
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Aggiunta documentazione di sqlite 3
2020-11-29 00:32:36 +01:00

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<title>Automatically Load Statically Linked Extensions</title>
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<a href="intro.html"><h2>SQLite C Interface</h2></a>
<h2>Automatically Load Statically Linked Extensions</h2>
</div>
<blockquote><pre>
int sqlite3_auto_extension(void(*xEntryPoint)(void));
</pre></blockquote>
<p>
This interface causes the xEntryPoint() function to be invoked for
each new <a href="../c3ref/sqlite3.html">database connection</a> that is created. The idea here is that
xEntryPoint() is the entry point for a statically linked <a href="../loadext.html">SQLite extension</a>
that is to be automatically loaded into all new database connections.</p>
<p>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:</p>
<p><blockquote><pre>
&nbsp; int xEntryPoint(
&nbsp; sqlite3 *db,
&nbsp; const char **pzErrMsg,
&nbsp; const struct sqlite3_api_routines *pThunk
&nbsp; );
</pre></blockquote></p>
<p>If the xEntryPoint routine encounters an error, it should make *pzErrMsg
point to an appropriate error message (obtained from <a href="../c3ref/mprintf.html">sqlite3_mprintf()</a>)
and return an appropriate <a href="../rescode.html">error code</a>. SQLite ensures that *pzErrMsg
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or <a href="../c3ref/open.html">sqlite3_open_v2()</a> call that provoked the xEntryPoint() will fail.</p>
<p>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.</p>
<p>See also: <a href="../c3ref/reset_auto_extension.html">sqlite3_reset_auto_extension()</a>
and <a href="../c3ref/cancel_auto_extension.html">sqlite3_cancel_auto_extension()</a>
</p><p>See also lists of
<a href="objlist.html">Objects</a>,
<a href="constlist.html">Constants</a>, and
<a href="funclist.html">Functions</a>.</p>