PHP 7.2.0 Beta 1 Released


(PHP 4, PHP 5, PHP 7)

session_destroyDestroys all data registered to a session


bool session_destroy ( void )

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.


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.

Return Values

Returns TRUE on success or FALSE on failure.


Example #1 Destroying a session with $_SESSION

// Initialize the session.
// If you are using session_name("something"), don't forget it now!

// 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.



Only use session_unset() for older deprecated code that does not use $_SESSION.

See Also

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User Contributed Notes 6 notes

Praveen V
4 years ago
If you want to change the session id on each log in, make sure to use session_regenerate_id(true) during the log in process.


[Edited by moderator (googleguy at php dot net)]
Jack Luo
3 years ago
It took me a while to figure out how to destroy a particular session in php. Note I'm not sure if solution provided below is perfect but it seems work for me. Please feel free to post any easier way to destroy a particular session. Because it's quite useful for functionality of force an user offline.

1. If you're using db or memcached to manage session, you can always delete that session entry directly from db or memcached.

2. Using generic php session methods to delete a particular session(by session id).

= 'nill2if998vhplq9f3pj08vjb1';
// 1. commit session if it's started.
if (session_id()) {

// 2. store current session id
$current_session_id = session_id();

// 3. hijack then destroy session specified.

// 4. restore current session id. If don't restore it, your current session will refer to the session you just destroyed!

17 days ago
I'm using PHP 7.1 and received the following warning when implementing Example #1, above:

    PHP message: PHP Warning:  session_destroy(): Trying to destroy uninitialized session in...

What I discovered is that clearing $_SESSION and removing the cookie destroys the session, hence the warning.  To avoid the warning while still keeping the value of using session_destroy(), do this after everything else:

    if (session_status() == PHP_SESSION_ACTIVE) { session_destroy(); }
10 years ago
Note that when you are using a custom session handler, session_destroy will cause a fatal error if you have set the session destroy function used by session_set_save_handler to private.

Fatal error: Call to private method Session::sessDestroy()

where sessDestroy was the function I specified in the 5th parameter of session_set_save_handler.

Even though it isn't all that desirable, the simple solution is to set sessDestroy to public.
10 months ago
For session_destroy() only destroy current session mean that if you specify name or change the save path of session etc  ,it will not destroy it mean for example


('testing') ;
session_start() ;

$_SESSION['id'] = '35' ;

() ;

session_destroy() ;

session_destroy only delete the new session which is created by session_start(). correct way is
('testing') ;
session_start() ;

session_destroy() ;

this is also valid for if you change path throught ini_set() , you have to mention in  delete.php.
remember session_destroy() function destroy  only current session not all .i hope this is worth to mention.
administrator at anorhack dot com
9 years ago
Destroying  a session from a background job

I have a thief-protection system that compares country codes from login IPs via whois. This has to run in the background as it is way too processor-hungry to be run in the browser.

What I needed was a way to destroy the web session from the background job. For some reason, a background session_destroy APPEARS to work, but doesnt't actually destroy the web session.

There is a work around, I set the username to NULL and the web code picks up on that, bouncing the user (thief) to a "gotcha" page where his IP is logged.

Yes I know its nasty and dirty, but surprisingly it works.

$sid = the session_id() of the suspicious web session, passed in $argv to the background job

The trick is to "stuff" the $_GET array with the sid, then the session_start in the background job picks this value up (as if it were a genuine trans-sid type thing...?PHPSESSID=blah) and "connects to" the web session. All $_SESSION variable can be viewed (and CHANGED , which is how this kludge works) but for some reason (that no doubt someone will illuminate) they can't be unset...setting the particular variable to NULL works well though:

// prove we are getting the web session data
foreach($_SESSION as $k => $v) echo($k."=".$v);
// now kill the thief
//web session variable now NULL - honestly!
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