term% cat index.txt ALARM(2) System Calls Manual ALARM(2)
NAME
alarm - schedule signal after specified time
SYNOPSIS
alarm(seconds)
unsigned seconds;
DESCRIPTION
Alarm causes signal SIGALRM, see signal(2), to be sent to the invoking
process in a number of seconds given by the argument. Unless caught or
ignored, the signal terminates the process.
Alarm requests are not stacked; successive calls reset the alarm clock.
If the argument is 0, any alarm request is canceled. Because the clock
has a 1-second resolution, the signal may occur up to one second early;
because of scheduling delays, resumption of execution of when the sig‐
nal is caught may be delayed an arbitrary amount. The longest specifi‐
able delay time is 2147483647 seconds.
The return value is the amount of time previously remaining in the
alarm clock.
SEE ALSO
pause(2), signal(2), sleep(3)
ALARM(2)