projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 5325ced3 CL |
1 | .\" Copyright (c) 1990 The Regents of the University of California. |
| 2 | .\" All rights reserved. | |
| 1039c22a | 3 | .\" |
| 5325ced3 | 4 | .\" %sccs.include.redist.man% |
| daacd5f0 | 5 | .\" |
| d0719240 | 6 | .\" @(#)sleep.1 6.4 (Berkeley) %G% |
| 5325ced3 CL |
7 | .\" |
| 8 | .Dd | |
| 9 | .Dt SLEEP 1 | |
| 10 | .Os BSD 4.4 | |
| 11 | .Sh NAME | |
| 12 | .Nm sleep | |
| 13 | .Nd suspend execution for an interval of time | |
| 14 | .Sh SYNOPSIS | |
| 15 | .Nm sleep | |
| 16 | .Ar seconds | |
| 17 | .Sh DESCRIPTION | |
| 18 | The | |
| 19 | .Nm sleep | |
| 20 | command | |
| 21 | suspends execution for a minimum of | |
| 22 | .Ar seconds . | |
| 23 | .Nm Sleep | |
| 24 | is used to schedule the execution of other commands (see | |
| 25 | EXAMPLES below). | |
| 26 | .Pp | |
| 27 | The | |
| 28 | .Nm Sleep | |
| 29 | utility exits with one of the following values: | |
| 30 | .Tw Ds | |
| 31 | .Tp Li \&0 | |
| 32 | On successful completetion, or if the signal SIGALRM was received. | |
| 33 | .Tp Li \&>\&0 | |
| 34 | An error occurred. | |
| 35 | .Tp | |
| 36 | .Sh EXAMPLES | |
| 37 | To schedule the execution of a command for | |
| 38 | .Va x | |
| 39 | number seconds later: | |
| 40 | .Pp | |
| 41 | .Dl (sleep 1800; sh command_file >& errors)& | |
| 42 | .Pp | |
| 43 | This incantation would wait a half hour before | |
| 44 | running the script command_file. (See the | |
| 45 | .Xr at 1 | |
| 46 | utility.) | |
| 47 | .Pp | |
| 48 | To reiteratively run a command (with the | |
| 49 | .Xr csh 1 ) : | |
| 50 | .Pp | |
| 51 | .Ds I | |
| 52 | while (1) | |
| 53 | if (! -r zzz.rawdata) then | |
| 54 | sleep 300 | |
| 55 | else | |
| 56 | foreach i (`ls *.rawdata`) | |
| 57 | sleep 70 | |
| 58 | awk -f collapse_data $i >> results | |
| 59 | end | |
| 60 | break | |
| 61 | endif | |
| 62 | end | |
| 63 | .De | |
| 64 | .Pp | |
| 65 | The scenario for a script such as this might be: a program currently | |
| 66 | running is taking longer than expected to process a series of | |
| 67 | files, and it would be nice to have | |
| 68 | another program start processing the files created by the first | |
| 69 | program as soon as it is finished (when zzz.rawdata is created). | |
| 70 | The script checks every five minutes for the file zzz.rawdata, | |
| 71 | when the file is found, then another portion processing | |
| 72 | is done curteously by sleeping for 70 seconds in between each | |
| 73 | awk job. | |
| 74 | .Sh SEE ALSO | |
| 75 | .Xr setitimer 2 , | |
| 76 | .Xr alarm 3 , | |
| 77 | .Xr sleep 3 , | |
| 78 | .Xr at 1 | |
| 79 | .Sh STANDARDS | |
| 80 | The sleep function is expected to be POSIX 1003.2 compatible. |