       alarm seconds
              Instructs  the  system  to send a SIGALRM signal in
              the  specified  number  of  seconds.   This  is   a
              floating  point  number,  so fractions 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.
