1BATCH(P) POSIX Programmer's Manual BATCH(P)
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6 batch - schedule commands to be executed in a batch queue
7
9 batch
10
12 The batch utility shall read commands from standard input and schedule
13 them for execution in a batch queue. It shall be the equivalent of the
14 command:
15 at -q b -m now
18 where queue b is a special at queue, specifically for batch jobs. Batch
20 jobs shall be submitted to the batch queue with no time constraints and
21 shall be run by the system using algorithms, based on unspecified fac‐
22 tors, that may vary with each invocation of batch.
23 Users shall be permitted to use batch if their name appears in the file
25 /usr/lib/cron/at.allow. If that file does not exist, the file
26 /usr/lib/cron/at.deny shall be checked to determine whether the user
27 shall be denied access to batch. If neither file exists, only a
28 process with the appropriate privileges shall be allowed to submit a
29 job. If only at.deny exists and is empty, global usage shall be permit‐
30 ted. The at.allow and at.deny files shall consist of one user name per
31 line.
32
34 None.
35
37 None.
38
40 The standard input shall be a text file consisting of commands accept‐
41 able to the shell command language described in Shell Command Language
42 .
43
45 The text files /usr/lib/cron/at.allow and /usr/lib/cron/at.deny shall
46 contain zero or more user names, one per line, of users who are,
47 respectively, authorized or denied access to the at and batch utili‐
48 ties.
49
51 The following environment variables shall affect the execution of
52 batch:
53 LANG Provide a default value for the internationalization variables
55 that are unset or null. (See the Base Definitions volume of
56 IEEE Std 1003.1-2001, Section 8.2, Internationalization Vari‐
57 ables for the precedence of internationalization variables used
58 to determine the values of locale categories.)
59 LC_ALL If set to a non-empty string value, override the values of all
61 the other internationalization variables.
62 LC_CTYPE
64 Determine the locale for the interpretation of sequences of
65 bytes of text data as characters (for example, single-byte as
66 opposed to multi-byte characters in arguments and input files).
67 LC_MESSAGES
69 Determine the locale that should be used to affect the format
70 and contents of diagnostic messages written to standard error
71 and informative messages written to standard output.
72 LC_TIME
74 Determine the format and contents for date and time strings
75 written by batch.
76 NLSPATH
78 Determine the location of message catalogs for the processing of
79 LC_MESSAGES .
80 SHELL Determine the name of a command interpreter to be used to invoke
82 the at-job. If the variable is unset or null, sh shall be used.
83 If it is set to a value other than a name for sh, the implemen‐
84 tation shall do one of the following: use that shell; use sh;
85 use the login shell from the user database; any of the preceding
86 accompanied by a warning diagnostic about which was chosen.
87 TZ Determine the timezone. The job shall be submitted for execution
89 at the time specified by timespec or -t time relative to the
90 timezone specified by the TZ variable. If timespec specifies a
91 timezone, it overrides TZ . If timespec does not specify a time‐
92 zone and TZ is unset or null, an unspecified default timezone
93 shall be used.
94
97 Default.
98
100 When standard input is a terminal, prompts of unspecified format for
101 each line of the user input described in the STDIN section may be writ‐
102 ten to standard output.
103
105 The following shall be written to standard error when a job has been
106 successfully submitted:
107 "job %s at %s\n", at_job_id, <date>
110 where date shall be equivalent in format to the output of:
112 date +"%a %b %e %T %Y"
115 The date and time written shall be adjusted so that they appear in the
117 timezone of the user (as determined by the TZ variable).
118 Neither this, nor warning messages concerning the selection of the com‐
120 mand interpreter, are considered a diagnostic that changes the exit
121 status.
122 Diagnostic messages, if any, shall be written to standard error.
124
126 None.
127
129 None.
130
132 The following exit values shall be returned:
133 0 Successful completion.
135 >0 An error occurred.
137
140 The job shall not be scheduled.
141 The following sections are informative.
143
145 It may be useful to redirect standard output within the specified com‐
146 mands.
147
149 1. This sequence can be used at a terminal:
150 batch
153 sort < file >outfile
154 EOT
155 2. This sequence, which demonstrates redirecting standard error to a
157 pipe, is useful in a command procedure (the sequence of output re‐
158 direction specifications is significant):
159 batch <<
162 ! diff file1 file2 2>&1 >outfile | mailx mygroup
163 !
164
166 Early proposals described batch in a manner totally separated from at,
167 even though the historical model treated it almost as a synonym for at
168 -qb. A number of features were added to list and control batch work
169 separately from those in at. Upon further reflection, it was decided
170 that the benefit of this did not merit the change to the historical
171 interface.
172 The -m option was included on the equivalent at command because it is
174 historical practice to mail results to the submitter, even if all job-
175 produced output is redirected. As explained in the RATIONALE for at,
176 the now keyword submits the job for immediate execution (after schedul‐
177 ing delays), despite some historical systems where at now would have
178 been considered an error.
179
181 None.
182
184 at
185
187 Portions of this text are reprinted and reproduced in electronic form
188 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
189 -- Portable Operating System Interface (POSIX), The Open Group Base
190 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
191 Electrical and Electronics Engineers, Inc and The Open Group. In the
192 event of any discrepancy between this version and the original IEEE and
193 The Open Group Standard, the original IEEE and The Open Group Standard
194 is the referee document. The original Standard can be obtained online
195 at http://www.opengroup.org/unix/online.html .
196IEEE/The Open Group 2003 BATCH(P)