sleep - suspend execution for an interval
sleep suspends execution for time seconds. It is used to execute a
command after a certain amount of time, as in:
(sleep 105; command)&&&&
or to execute a command periodically, as in:
sleep exits with one of the following values:
0 The execution was successfully suspended for time seconds,
or a SIGALRM signal was received.
>>>>0 If the time operand is missing, is not a decimal integer, is
negative, or is greater than UINT_MAX, sleep returns with
exit status 2.
sleep: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2
Hewlett-Packard Company - 1 - HP-UX Release 11i: November 2000