       alarm seconds
              Instructs  the  system to send a SIGALRM signal in the specified
              number of seconds.  This is a floating point  number,  so  frac-
              tions  of  a  section  may be specified.  If seconds is 0.0, any
              previous alarm request is canceled.  Only one alarm  at  a  time
              may be active; the command returns the number of seconds left in
              the previous alarm.  On systems  without  the  setitimer  system
              call, seconds is rounded up to an integer number of seconds.

              The alarm command is not available on Windows 95/NT.
