(PHP 4 >= 4.3.0, PHP 5)
pcntl_alarm — Set an alarm clock for delivery of a signal
Creates a timer that will send a SIGALRM signal to the process after the given number of seconds. Any call to pcntl_alarm() will cancel any previously set alarm.
The number of seconds to wait. If seconds is zero, no new alarm is created.
Returns the time in seconds that any previously scheduled alarm had remaining before it was to be delivered, or 0 if there was no previously scheduled alarm.