RTEMS 4.9.2 On-Line Library

Signal Manager alarm - Schedule Alarm

RTEMS POSIX API User's Guide

2.4.18: alarm - Schedule Alarm

CALLING SEQUENCE:

#include <unistd.h>

unsigned int alarm(
  unsigned int seconds
);

STATUS CODES:

This call always succeeds.

If there was a previous alarm() request with time remaining, then this routine returns the number of seconds until that outstanding alarm would have fired. If no previous alarm() request was outstanding, then zero is returned.

DESCRIPTION:

The alarm() service causes the SIGALRM signal to be generated after the number of seconds specified by seconds has elapsed.

NOTES:

Alarm requests do not queue. If alarm is called while a previous request is outstanding, the call will result in rescheduling the time at which the SIGALRM signal will be generated.

If the notification signal, SIGALRM, is not caught or ignored, the calling process is terminated.

RTEMS POSIX API User's Guide