SLEEP(1)                    386BSD Reference 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. Sleep is
     used to schedule the execution of other commands (see EXAMPLES below).

     The Sleep utility exits with one of the following values:

     0     On successful completetion, or if the signal SIGALRM was received.

     >0    An error occurred.

EXAMPLES
     To schedule the execution of a command for x number seconds later:

           (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 curteously by sleeping for 70 seconds in between each awk job.

SEE ALSO
     setitimer(2),  alarm(3),  sleep(3),  at(1)

STANDARDS
     The sleep command is expected to be IEEE Std1003.2 (``POSIX'')
     compatible.

BSD Experimental                 July 27, 1991                               1