June 2002
Beginner
759 pages
80h 42m
English
alarm
alarm n
Sends a SIGALRM
signal to the executing Perl program after
n seconds. On some older systems,
alarms go off “at the top of the second,” so, for instance, an
alarm 1 may go off anywhere
between 0 to 1 seconds from now, depending on when in the current
second it is. An alarm 2 may go
off anywhere from 1 to 2 seconds from now. And so on.
Each call disables the previous timer, and an argument of
0 may be supplied to cancel the
previous timer without starting a new one. The return value is the
number of seconds remaining on the previous timer.