session_destroy
(PHP 4, PHP 5, PHP 7, PHP 8)
session_destroy — Destroys all data registered to a session
Description
function session_destroy():
bool
session_destroy() destroys all of the data associated
with the current session. It does not unset any of the global variables
associated with the session, or unset the session cookie.
To use the session variables again, session_start() has
to be called.
Note:
You do not have to call session_destroy() from usual
code. Cleanup $_SESSION array rather than destroying session data.
In order to kill the session altogether, the
session ID must also be unset. If a cookie is used to propagate the
session ID (default behavior), then the session cookie must be deleted.
setcookie() may be used for that.
When session.use_strict_mode
is enabled. You do not have to remove obsolete session ID cookie because
session module will not accept session ID cookie when there is no
data associated to the session ID and set new session ID cookie.
Enabling session.use_strict_mode
is recommended for all sites.
Warning
Immediate session deletion may cause unwanted results. When there is
concurrent requests, other connections may see sudden session data
loss. e.g. Requests from JavaScript and/or requests from URL links.
Although current session module does not accept empty session ID
cookie, but immediate session deletion may result in empty session ID
cookie due to client(browser) side race condition. This will result
that the client creates many session ID needlessly.
To avoid these, you must set deletion time-stamp to $_SESSION and
reject access while later. Or make sure your application does not
have concurrent requests. This applies to session_regenerate_id() also.
Parameters
This function has no parameters.
Return Values
Returns true on success or false on failure.
Examples
Example #1 Destroying a session with $_SESSION
<?php
// Initialize the session.
// If you are using session_name("something"), don't forget it now!
session_start();
// Unset all of the session variables.
$_SESSION = array();
// If it's desired to kill the session, also delete the session cookie.
// Note: This will destroy the session, and not just the session data!
if (ini_get("session.use_cookies")) {
$params = session_get_cookie_params();
setcookie(session_name(), '', time() - 42000,
$params["path"], $params["domain"],
$params["secure"], $params["httponly"]
);
}
// Finally, destroy the session.
session_destroy();
?>
session_decode
Session Functions