180 lines
6.5 KiB
HTML
180 lines
6.5 KiB
HTML
<!DOCTYPE html>
|
|
<html><head>
|
|
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
|
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
|
|
<link href="../sqlite.css" rel="stylesheet">
|
|
<title>Database Connection Client Data</title>
|
|
<!-- path=../ -->
|
|
</head>
|
|
<body>
|
|
<div class=nosearch>
|
|
<a href="../index.html">
|
|
<img class="logo" src="../images/sqlite370_banner.gif" alt="SQLite" border="0">
|
|
</a>
|
|
<div><!-- IE hack to prevent disappearing logo --></div>
|
|
<div class="tagline desktoponly">
|
|
Small. Fast. Reliable.<br>Choose any three.
|
|
</div>
|
|
<div class="menu mainmenu">
|
|
<ul>
|
|
<li><a href="../index.html">Home</a>
|
|
<li class='mobileonly'><a href="javascript:void(0)" onclick='toggle_div("submenu")'>Menu</a>
|
|
<li class='wideonly'><a href='../about.html'>About</a>
|
|
<li class='desktoponly'><a href="../docs.html">Documentation</a>
|
|
<li class='desktoponly'><a href="../download.html">Download</a>
|
|
<li class='wideonly'><a href='../copyright.html'>License</a>
|
|
<li class='desktoponly'><a href="../support.html">Support</a>
|
|
<li class='desktoponly'><a href="../prosupport.html">Purchase</a>
|
|
<li class='search' id='search_menubutton'>
|
|
<a href="javascript:void(0)" onclick='toggle_search()'>Search</a>
|
|
</ul>
|
|
</div>
|
|
<div class="menu submenu" id="submenu">
|
|
<ul>
|
|
<li><a href='../about.html'>About</a>
|
|
<li><a href='../docs.html'>Documentation</a>
|
|
<li><a href='../download.html'>Download</a>
|
|
<li><a href='../support.html'>Support</a>
|
|
<li><a href='../prosupport.html'>Purchase</a>
|
|
</ul>
|
|
</div>
|
|
<div class="searchmenu" id="searchmenu">
|
|
<form method="GET" action="../search">
|
|
<select name="s" id="searchtype">
|
|
<option value="d">Search Documentation</option>
|
|
<option value="c">Search Changelog</option>
|
|
</select>
|
|
<input type="text" name="q" id="searchbox" value="">
|
|
<input type="submit" value="Go">
|
|
</form>
|
|
</div>
|
|
</div>
|
|
<script>
|
|
function toggle_div(nm) {
|
|
var w = document.getElementById(nm);
|
|
if( w.style.display=="block" ){
|
|
w.style.display = "none";
|
|
}else{
|
|
w.style.display = "block";
|
|
}
|
|
}
|
|
function toggle_search() {
|
|
var w = document.getElementById("searchmenu");
|
|
if( w.style.display=="block" ){
|
|
w.style.display = "none";
|
|
} else {
|
|
w.style.display = "block";
|
|
setTimeout(function(){
|
|
document.getElementById("searchbox").focus()
|
|
}, 30);
|
|
}
|
|
}
|
|
function div_off(nm){document.getElementById(nm).style.display="none";}
|
|
window.onbeforeunload = function(e){div_off("submenu");}
|
|
/* Disable the Search feature if we are not operating from CGI, since */
|
|
/* Search is accomplished using CGI and will not work without it. */
|
|
if( !location.origin || !location.origin.match || !location.origin.match(/http/) ){
|
|
document.getElementById("search_menubutton").style.display = "none";
|
|
}
|
|
/* Used by the Hide/Show button beside syntax diagrams, to toggle the */
|
|
function hideorshow(btn,obj){
|
|
var x = document.getElementById(obj);
|
|
var b = document.getElementById(btn);
|
|
if( x.style.display!='none' ){
|
|
x.style.display = 'none';
|
|
b.innerHTML='show';
|
|
}else{
|
|
x.style.display = '';
|
|
b.innerHTML='hide';
|
|
}
|
|
return false;
|
|
}
|
|
var antiRobot = 0;
|
|
function antiRobotGo(){
|
|
if( antiRobot!=3 ) return;
|
|
antiRobot = 7;
|
|
var j = document.getElementById("mtimelink");
|
|
if(j && j.hasAttribute("data-href")) j.href=j.getAttribute("data-href");
|
|
}
|
|
function antiRobotDefense(){
|
|
document.body.onmousedown=function(){
|
|
antiRobot |= 2;
|
|
antiRobotGo();
|
|
document.body.onmousedown=null;
|
|
}
|
|
document.body.onmousemove=function(){
|
|
antiRobot |= 2;
|
|
antiRobotGo();
|
|
document.body.onmousemove=null;
|
|
}
|
|
setTimeout(function(){
|
|
antiRobot |= 1;
|
|
antiRobotGo();
|
|
}, 100)
|
|
antiRobotGo();
|
|
}
|
|
antiRobotDefense();
|
|
</script>
|
|
<!-- keywords: sqlite3_get_clientdata sqlite3_set_clientdata -->
|
|
<div class=nosearch>
|
|
<a href="../c3ref/intro.html"><h2>SQLite C Interface</h2></a>
|
|
<h2>Database Connection Client Data</h2>
|
|
</div>
|
|
<blockquote><pre>
|
|
void *sqlite3_get_clientdata(sqlite3*,const char*);
|
|
int sqlite3_set_clientdata(sqlite3*, const char*, void*, void(*)(void*));
|
|
</pre></blockquote>
|
|
<p>
|
|
These functions are used to associate one or more named pointers
|
|
with a <a href="../c3ref/sqlite3.html">database connection</a>.
|
|
A call to sqlite3_set_clientdata(D,N,P,X) causes the pointer P
|
|
to be attached to <a href="../c3ref/sqlite3.html">database connection</a> D using name N. Subsequent
|
|
calls to sqlite3_get_clientdata(D,N) will return a copy of pointer P
|
|
or a NULL pointer if there were no prior calls to
|
|
sqlite3_set_clientdata() with the same values of D and N.
|
|
Names are compared using strcmp() and are thus case sensitive.</p>
|
|
|
|
<p>If P and X are both non-NULL, then the destructor X is invoked with
|
|
argument P on the first of the following occurrences:
|
|
<ul>
|
|
<li> An out-of-memory error occurs during the call to
|
|
sqlite3_set_clientdata() which attempts to register pointer P.
|
|
<li> A subsequent call to sqlite3_set_clientdata(D,N,P,X) is made
|
|
with the same D and N parameters.
|
|
<li> The database connection closes. SQLite does not make any guarantees
|
|
about the order in which destructors are called, only that all
|
|
destructors will be called exactly once at some point during the
|
|
database connection closing process.
|
|
</ul></p>
|
|
|
|
<p>SQLite does not do anything with client data other than invoke
|
|
destructors on the client data at the appropriate time. The intended
|
|
use for client data is to provide a mechanism for wrapper libraries
|
|
to store additional information about an SQLite database connection.</p>
|
|
|
|
<p>There is no limit (other than available memory) on the number of different
|
|
client data pointers (with different names) that can be attached to a
|
|
single database connection. However, the implementation is optimized
|
|
for the case of having only one or two different client data names.
|
|
Applications and wrapper libraries are discouraged from using more than
|
|
one client data name each.</p>
|
|
|
|
<p>There is no way to enumerate the client data pointers
|
|
associated with a database connection. The N parameter can be thought
|
|
of as a secret key such that only code that knows the secret key is able
|
|
to access the associated data.</p>
|
|
|
|
<p>Security Warning: These interfaces should not be exposed in scripting
|
|
languages or in other circumstances where it might be possible for an
|
|
an attacker to invoke them. Any agent that can invoke these interfaces
|
|
can probably also take control of the process.</p>
|
|
|
|
<p>Database connection client data is only available for SQLite
|
|
version 3.44.0 (2023-11-01) and later.</p>
|
|
|
|
<p>See also: <a href="../c3ref/get_auxdata.html">sqlite3_set_auxdata()</a> and <a href="../c3ref/get_auxdata.html">sqlite3_get_auxdata()</a>.
|
|
</p><p>See also lists of
|
|
<a href="../c3ref/objlist.html">Objects</a>,
|
|
<a href="../c3ref/constlist.html">Constants</a>, and
|
|
<a href="../c3ref/funclist.html">Functions</a>.</p>
|
|
|