NAME    [Toc]    [Back]

     alarm - set signal timer alarm

SYNOPSIS    [Toc]    [Back]

     #include <unistd.h>

     unsigned int
     alarm(unsigned int seconds);

DESCRIPTION    [Toc]    [Back]

     This interface is made obsolete by setitimer(2).

     The alarm() function waits a count of seconds before asserting the terminating
  signal  SIGALRM.   When  the signal has successfully
been caught,
     alarm() returns the amount of time left on the  clock.   The
maximum number
     of seconds allowed is 100000000.

     If  an  alarm  has  been  set  with alarm(), another call to
alarm() will supersede
 the prior call.  The request alarm(0) voids the current alarm.

RETURN VALUES    [Toc]    [Back]

     If  the call succeeds, any time left remaining from a previous call is returned.
  If an error occurs, the value -1 is returned, and a
more precise
     error code is placed in the global variable errno.

SEE ALSO    [Toc]    [Back]

     setitimer(2),    sigaction(2),    signal(3),    sigpause(3),
sigvec(3), sleep(3),
     ualarm(3), usleep(3)

STANDARDS    [Toc]    [Back]

     The  alarm()  function  conforms  to  IEEE  Std  1003.1-1990
(``POSIX'').

HISTORY    [Toc]    [Back]

     An alarm() function appeared in Version 7 AT&T UNIX.

OpenBSD      3.6                          April      19,     1994