sleep(1) [mojave man page]

SLEEP(1)						    BSD 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-
     portable extension, and its use will nearly guarantee that a shell script will not execute properly on another system.

EXIT STATUS

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

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 command_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 running 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 created).  The script checks every five minutes for the file zzz.rawdata, when the file is found, then another portion processing is done
     courteously by sleeping for 70 seconds in between each awk job.

SEE ALSO

     nanosleep(2), sleep(3)

STANDARDS

     The sleep command is expected to be IEEE Std 1003.2 (``POSIX.2'') compatible.

HISTORY

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

BSD
								  April 18, 1994							       BSD

sleep(3UCB)					     SunOS/BSD Compatibility Library Functions					       sleep(3UCB)

NAME

       sleep - suspend execution for interval

SYNOPSIS

       /usr/ucb/cc [ flag ... ] file ...

       int sleep(seconds)
       unsigned seconds;

DESCRIPTION

       sleep() suspends the current process from execution for the number of seconds specified by the argument.  The actual suspension time may be
       up to 1 second less than that requested, because scheduled wakeups occur at fixed 1-second intervals, and may be an arbitrary amount longer
       because of other activity in the system.

       sleep()	is implemented by setting an interval timer and pausing until it expires.  The previous state of this timer is saved and restored.
       If the sleep time exceeds the time to the expiration of the previous value of the timer, the process sleeps only until the timer would have
       expired, and the signal which occurs with the expiration of the timer is sent one second later.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Async-Signal-Safe 	   |
       +-----------------------------+-----------------------------+

SEE ALSO

       cc(1B), alarm(2), getitimer(2), longjmp(3C), siglongjmp(3C), sleep(3C), usleep(3C), attributes(5)

NOTES

       Use of these interfaces should be restricted to only applications written on BSD platforms.  Use of these interfaces with any of the system
       libraries or in multi-thread applications is unsupported.

       SIGALRM should not be blocked or ignored during a call to sleep(). Only a prior call to alarm(2) should generate SIGALRM  for  the  calling
       process	during	a call to sleep(). A signal-catching function should not interrupt a call to sleep() to call siglongjmp(3C) or longjmp(3C)
       to restore an environment saved prior to the sleep() call.

WARNINGS

       sleep() is slightly incompatible with alarm(2). Programs that do not execute for at least one second of clock time between successive calls
       to  sleep()  indefinitely  delay  the alarm signal. Use sleep(3C). Each sleep(3C) call postpones the alarm signal that would have been sent
       during the requested sleep period to occur one second later.

SunOS 5.11							    30 Oct 2007 						       sleep(3UCB)