If your script exceeds the maximum execution time, and terminates thusly:

Fatal error: Maximum execution time of 20 seconds exceeded in - on line 12

The registered shutdown functions will still be executed.

I figured it was important that this be made clear!
----
Manual Page -- [url]http://www.php.net/manual/en/function.register-shutdown-function.php[/url]
Edit Note -- [url]http://master.php.net/manage/user-notes.php?action=edit+33575[/url]
Delete Note -- [url]http://master.php.net/manage/user-notes.php?action=delete+33575&report=yes[/url]
Reject Note -- [url]http://master.php.net/manage/user-notes.php?action=reject+33575&report=yes[/url]