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>Load An Extension</title>
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<a href="intro.html"><h2>SQLite C Interface</h2></a>
<h2>Load An Extension</h2>
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<blockquote><pre>
int sqlite3_load_extension(
sqlite3 *db, /* Load the extension into this database connection */
const char *zFile, /* Name of the shared library containing extension */
const char *zProc, /* Entry point. Derived from zFile if 0 */
char **pzErrMsg /* Put error message here if not 0 */
);
</pre></blockquote>
<p>
This interface loads an SQLite extension library from the named file.</p>
<p>The sqlite3_load_extension() interface attempts to load an
<a href="../loadext.html">SQLite extension</a> library contained in the file zFile. If
the file cannot be loaded directly, attempts are made to load
with various operating-system specific extensions added.
So for example, if "samplelib" cannot be loaded, then names like
"samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
be tried also.</p>
<p>The entry point is zProc.
zProc may be 0, in which case SQLite will try to come up with an
entry point name on its own. It first tries "sqlite3_extension_init".
If that does not work, it constructs a name "sqlite3_X_init" where the
X is consists of the lower-case equivalent of all ASCII alphabetic
characters in the filename from the last "/" to the first following
"." and omitting any initial "lib".
The sqlite3_load_extension() interface returns
<a href="../rescode.html#ok">SQLITE_OK</a> on success and <a href="../rescode.html#error">SQLITE_ERROR</a> if something goes wrong.
If an error occurs and pzErrMsg is not 0, then the
<a href="../c3ref/load_extension.html">sqlite3_load_extension()</a> interface shall attempt to
fill *pzErrMsg with error message text stored in memory
obtained from <a href="../c3ref/free.html">sqlite3_malloc()</a>. The calling function
should free this memory by calling <a href="../c3ref/free.html">sqlite3_free()</a>.</p>
<p>Extension loading must be enabled using
<a href="../c3ref/enable_load_extension.html">sqlite3_enable_load_extension()</a> or
<a href="../c3ref/db_config.html">sqlite3_db_config</a>(db,<a href="../c3ref/c_dbconfig_defensive.html#sqlitedbconfigenableloadextension">SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</a>,1,NULL)
prior to calling this API,
otherwise an error will be returned.</p>
<p><b>Security warning:</b> It is recommended that the
<a href="../c3ref/c_dbconfig_defensive.html#sqlitedbconfigenableloadextension">SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</a> method be used to enable only this
interface. The use of the <a href="../c3ref/enable_load_extension.html">sqlite3_enable_load_extension()</a> interface
should be avoided. This will keep the SQL function <a href="../lang_corefunc.html#load_extension">load_extension()</a>
disabled and prevent SQL injections from giving attackers
access to extension loading capabilities.</p>
<p>See also the <a href="../lang_corefunc.html#load_extension">load_extension() SQL function</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>