alarm

Purpose

     Sets a process's alarm clock.

Syntax

     unsigned int alarm (sec)
     unsigned int sec;

Description

     The  alarm system  call instructs  the calling  process's
     alarm  clock to  send  a SIGALRM  signal  to the  calling
     process after  the number of real-time  seconds specified
     by  the sec  parameter have  elapsed.  (See  "signal" for
     more information about signals.)

     The alarm system calls are not stacked.  Successive alarm
     system calls reset the calling process's alarm clock.

     If the sec parameter is  0, any previous alarm request is
     canceled.

Return Value

     The alarm system  call returns the amount  of time previ-
     ously remaining in the calling process's alarm clock.  If
     no alarm request was previously issued, then a value of 0
     is returned.

Related Information

     In this book:  "pause" and "signal."