session_regenerate_id

(PHP 4 >= 4.3.2, PHP 5, PHP 7)

Update the current session id with a newly generated one

bool session_regenerate_id ([ bool $delete_old_session = false ] )

session_regenerate_id() will replace the current session id with a new one, and keep the current session information.

When session.use_trans_sid is enabled, output must be started after session_regenerate_id() call. Otherwise, old session ID is used.

Parameters:

delete_old_session

Whether to delete the old associated session file or not.

Returns:

Returns TRUE on success or FALSE on failure.

Changelog:

4.3.3

Since then, if session cookies are enabled, use of session_regenerate_id() will also submit a new session cookie with the new session id.

5.1.0

Added the delete_old_session parameter.

Examples:

A session_regenerate_id() example

<?php
session_start();

$old_sessionid = session_id();

session_regenerate_id();

$new_sessionid = session_id();

echo "Old Session: $old_sessionid<br />";
echo "New Session: $new_sessionid<br />";

print_r($_SESSION);
?>