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1.1 root 1: .\" Copyright (c) 1990 The Regents of the University of California.
2: .\" All rights reserved.
3: .\"
4: .\" Redistribution and use in source and binary forms are permitted provided
5: .\" that: (1) source distributions retain this entire copyright notice and
6: .\" comment, and (2) distributions including binaries display the following
7: .\" acknowledgement: ``This product includes software developed by the
8: .\" University of California, Berkeley and its contributors'' in the
9: .\" documentation or other materials provided with the distribution and in
10: .\" all advertising materials mentioning features or use of this software.
11: .\" Neither the name of the University nor the names of its contributors may
12: .\" be used to endorse or promote products derived from this software without
13: .\" specific prior written permission.
14: .\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
15: .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
16: .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
17: .\"
18: .\" @(#)sleep.1 6.3 (Berkeley) 7/24/90
19: .\"
20: .Dd July 24, 1990
21: .Dt SLEEP 1
22: .Os BSD 4.4
23: .Sh NAME
24: .Nm sleep
25: .Nd suspend execution for an interval of time
26: .Sh SYNOPSIS
27: .Nm sleep
28: .Ar seconds
29: .Sh DESCRIPTION
30: The
31: .Nm sleep
32: command
33: suspends execution for a minimum of
34: .Ar seconds .
35: .Nm Sleep
36: is used to schedule the execution of other commands (see
37: EXAMPLES below).
38: .Pp
39: The
40: .Nm Sleep
41: utility exits with one of the following values:
42: .Tw Ds
43: .Tp Li \&0
44: On successful completetion, or if the signal SIGALRM was received.
45: .Tp Li \&>\&0
46: An error occurred.
47: .Tp
48: .Sh EXAMPLES
49: To schedule the execution of a command for
50: .Va x
51: number seconds later:
52: .Pp
53: .Dl (sleep 1800; sh command_file >& errors)&
54: .Pp
55: This incantation would wait a half hour before
56: running the script command_file. (See the
57: .Xr at 1
58: utility.)
59: .Pp
60: To reiteratively run a command (with the
61: .Xr csh 1 ) :
62: .Pp
63: .Ds I
64: while (1)
65: if (! -r zzz.rawdata) then
66: sleep 300
67: else
68: foreach i (`ls *.rawdata`)
69: sleep 70
70: awk -f collapse_data $i >> results
71: end
72: break
73: endif
74: end
75: .De
76: .Pp
77: The scenario for a script such as this might be: a program currently
78: running is taking longer than expected to process a series of
79: files, and it would be nice to have
80: another program start processing the files created by the first
81: program as soon as it is finished (when zzz.rawdata is created).
82: The script checks every five minutes for the file zzz.rawdata,
83: when the file is found, then another portion processing
84: is done curteously by sleeping for 70 seconds in between each
85: awk job.
86: .Sh SEE ALSO
87: .Xr setitimer 2 ,
88: .Xr alarm 3 ,
89: .Xr sleep 3 ,
90: .Xr at 1
91: .Sh STANDARDS
92: The sleep function is expected to be POSIX 1003.2 compatible.
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