session_regenerate_id — Updating Existing Session ID with a New One in PHP

The PHP function session_regenerate_id() replaces the current session ID with a newly generated one without altering the session data.

Parameter: $delete_old_session (bool) determines whether the old session storage file is removed.

Return value: Returns TRUE on success, FALSE on failure.

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);
?>