session_unregister() unregisters (forgets) the global variable named name from the current session.
This function returns TRUE when the variable is successfully unregistered from the session.
Note: If $_SESSION (or $HTTP_SESSION_VARS for PHP 4.0.6 or less) is used, use unset() to unregister a session variable.
| Caution |
This function doesn't unset the corresponding global variable for name, it only prevents the variable from being saved as part of the session. You must call unset() to remove the corresponding global variable. |
| Caution |
If you are using $_SESSION (or $HTTP_SESSION_VARS), do not use session_register(), session_is_registered() and session_unregister(). |