bsd man page for sleep

SLEEP(1)						      General Commands Manual							  SLEEP(1)

NAME
       sleep - suspend execution for an interval

SYNOPSIS
       sleep time

DESCRIPTION
       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 every so often, as in:

	    while true
	    do
		 command
		 sleep 37
	    done

SEE ALSO
       setitimer(2), alarm(3C), sleep(3)

BUGS
       Time must be less than 2,147,483,647 seconds.

7th Edition							  April 29, 1985							  SLEEP(1)