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SLEEP(1)		FreeBSD	General	Commands Manual		      SLEEP(1)

NAME
     sleep -- suspend execution	for an interval	of time

SYNOPSIS
     sleep seconds

DESCRIPTION
     The sleep command suspends	execution for a	minimum	of seconds.

     If	the sleep command receives a signal, it	takes the standard action.

IMPLEMENTATION NOTES
     The SIGALRM signal	is not handled specially by this implementation.

     The sleep command will accept and honor a non-integer number of specified
     seconds (with a `.' character as a	decimal	point).	 This is a non-porta-
     ble extension, and	its use	will nearly guarantee that a shell script will
     not execute properly on another system.

EXAMPLES
     To	schedule the execution of a command for	x number seconds later (with
     csh(1)):

	   (sleep 1800;	sh command_file	>& errors)&

     This incantation would wait a half	hour before running the	script com-
     mand_file.	 (See the at(1)	utility.)

     To	reiteratively run a command (with the csh(1)):

	   while (1)
		   if (! -r zzz.rawdata) then
			   sleep 300
		   else
			   foreach i (`ls *.rawdata`)
				   sleep 70
				   awk -f collapse_data	$i >> results
			   end
			   break
		   endif
	   end

     The scenario for a	script such as this might be: a	program	currently run-
     ning is taking longer than	expected to process a series of	files, and it
     would be nice to have another program start processing the	files created
     by	the first program as soon as it	is finished (when zzz.rawdata is cre-
     ated).  The script	checks every five minutes for the file zzz.rawdata,
     when the file is found, then another portion processing is	done courte-
     ously by sleeping for 70 seconds in between each awk job.

DIAGNOSTICS
     The sleep utility exits 0 on success, and >0 if an	error occurs.

SEE ALSO
     nanosleep(2), sleep(3)

STANDARDS
     The sleep command is expected to be IEEE Std 1003.2 (``POSIX.2'') compat-
     ible.

HISTORY
     A sleep command appeared in Version 4 AT&T	UNIX.

FreeBSD	9.2			April 18, 1994			   FreeBSD 9.2

NAME | SYNOPSIS | DESCRIPTION | IMPLEMENTATION NOTES | EXAMPLES | DIAGNOSTICS | SEE ALSO | STANDARDS | HISTORY

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