In order to prevent my script timing out (I was processing images which was taking some time) I added this into my loop:
This resets the time limit - in this example giving it another 25 seconds to complete the task.
(PHP 4 <= 4.0.4)
connection_timeout — Check if the script timed out
Determines whether the script timed out.
Returns 1 if the script timed out, 0 otherwise.
This function is deprecated, and doesn't even exist anymore as of 4.0.5.