mirror of https://github.com/mkerrisk/man-pages
239 lines
6.8 KiB
Groff
239 lines
6.8 KiB
Groff
|
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
|
||
|
.TH "BATCH" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
|
||
|
.\" batch
|
||
|
.SH NAME
|
||
|
batch \- schedule commands to be executed in a batch queue
|
||
|
.SH SYNOPSIS
|
||
|
.LP
|
||
|
\fB\fP \fIbatch\fP\fB\fP
|
||
|
.SH DESCRIPTION
|
||
|
.LP
|
||
|
The \fIbatch\fP utility shall read commands from standard input and
|
||
|
schedule them for execution in a batch queue. It shall be
|
||
|
the equivalent of the command:
|
||
|
.sp
|
||
|
.RS
|
||
|
.nf
|
||
|
|
||
|
\fBat -q b -m now
|
||
|
\fP
|
||
|
.fi
|
||
|
.RE
|
||
|
.LP
|
||
|
where queue \fIb\fP is a special \fIat\fP queue, specifically for
|
||
|
batch jobs. Batch jobs
|
||
|
shall be submitted to the batch queue with no time constraints and
|
||
|
shall be run by the system using algorithms, based on
|
||
|
unspecified factors, that may vary with each invocation of \fIbatch\fP.
|
||
|
.LP
|
||
|
Users shall be permitted to use \fIbatch\fP if their name appears
|
||
|
in the file \fB/usr/lib/cron/at.allow\fP. If that file does not
|
||
|
exist, the file \fB/usr/lib/cron/at.deny\fP shall be checked to determine
|
||
|
whether the user shall be denied access to \fIbatch\fP.
|
||
|
If neither file exists, only a process with the appropriate privileges
|
||
|
shall be allowed to submit a job. If only \fBat.deny\fP
|
||
|
exists and is empty, global usage shall be permitted. The \fBat.allow\fP
|
||
|
and \fBat.deny\fP files shall consist of one user name
|
||
|
per line.
|
||
|
.SH OPTIONS
|
||
|
.LP
|
||
|
None.
|
||
|
.SH OPERANDS
|
||
|
.LP
|
||
|
None.
|
||
|
.SH STDIN
|
||
|
.LP
|
||
|
The standard input shall be a text file consisting of commands acceptable
|
||
|
to the shell command language described in \fIShell Command Language\fP
|
||
|
\&.
|
||
|
.SH INPUT FILES
|
||
|
.LP
|
||
|
The text files \fB/usr/lib/cron/at.allow\fP and \fB/usr/lib/cron/at.deny\fP
|
||
|
shall contain zero or more user names, one per line,
|
||
|
of users who are, respectively, authorized or denied access to the
|
||
|
\fIat\fP and \fIbatch\fP
|
||
|
utilities.
|
||
|
.SH ENVIRONMENT VARIABLES
|
||
|
.LP
|
||
|
The following environment variables shall affect the execution of
|
||
|
\fIbatch\fP:
|
||
|
.TP 7
|
||
|
\fILANG\fP
|
||
|
Provide a default value for the internationalization variables that
|
||
|
are unset or null. (See the Base Definitions volume of
|
||
|
IEEE\ Std\ 1003.1-2001, Section 8.2, Internationalization Variables
|
||
|
for
|
||
|
the precedence of internationalization variables used to determine
|
||
|
the values of locale categories.)
|
||
|
.TP 7
|
||
|
\fILC_ALL\fP
|
||
|
If set to a non-empty string value, override the values of all the
|
||
|
other internationalization variables.
|
||
|
.TP 7
|
||
|
\fILC_CTYPE\fP
|
||
|
Determine the locale for the interpretation of sequences of bytes
|
||
|
of text data as characters (for example, single-byte as
|
||
|
opposed to multi-byte characters in arguments and input files).
|
||
|
.TP 7
|
||
|
\fILC_MESSAGES\fP
|
||
|
Determine the locale that should be used to affect the format and
|
||
|
contents of diagnostic messages written to standard error and
|
||
|
informative messages written to standard output.
|
||
|
.TP 7
|
||
|
\fILC_TIME\fP
|
||
|
Determine the format and contents for date and time strings written
|
||
|
by \fIbatch\fP.
|
||
|
.TP 7
|
||
|
\fINLSPATH\fP
|
||
|
Determine the location of message catalogs for the processing of \fILC_MESSAGES
|
||
|
\&.\fP
|
||
|
.TP 7
|
||
|
\fISHELL\fP
|
||
|
Determine the name of a command interpreter to be used to invoke the
|
||
|
at-job. If the variable is unset or null, \fIsh\fP shall be used.
|
||
|
If it is set to a value other than a name for \fIsh\fP, the implementation
|
||
|
shall do one of the following: use that shell; use \fIsh\fP; use the
|
||
|
login shell from the user database; any of the preceding accompanied
|
||
|
by a warning
|
||
|
diagnostic about which was chosen.
|
||
|
.TP 7
|
||
|
\fITZ\fP
|
||
|
Determine the timezone. The job shall be submitted for execution at
|
||
|
the time specified by \fItimespec\fP or \fB-t\fP
|
||
|
\fItime\fP relative to the timezone specified by the \fITZ\fP variable.
|
||
|
If \fItimespec\fP specifies a timezone, it overrides
|
||
|
\fITZ .\fP If \fItimespec\fP does not specify a timezone and \fITZ\fP
|
||
|
is unset or null, an unspecified default timezone shall be
|
||
|
used.
|
||
|
.sp
|
||
|
.SH ASYNCHRONOUS EVENTS
|
||
|
.LP
|
||
|
Default.
|
||
|
.SH STDOUT
|
||
|
.LP
|
||
|
When standard input is a terminal, prompts of unspecified format for
|
||
|
each line of the user input described in the STDIN section
|
||
|
may be written to standard output.
|
||
|
.SH STDERR
|
||
|
.LP
|
||
|
The following shall be written to standard error when a job has been
|
||
|
successfully submitted:
|
||
|
.sp
|
||
|
.RS
|
||
|
.nf
|
||
|
|
||
|
\fB"job %s at %s\\n",\fP \fIat_job_id\fP\fB, <\fP\fIdate\fP\fB>
|
||
|
\fP
|
||
|
.fi
|
||
|
.RE
|
||
|
.LP
|
||
|
where \fIdate\fP shall be equivalent in format to the output of:
|
||
|
.sp
|
||
|
.RS
|
||
|
.nf
|
||
|
|
||
|
\fBdate +"%a %b %e %T %Y"
|
||
|
\fP
|
||
|
.fi
|
||
|
.RE
|
||
|
.LP
|
||
|
The date and time written shall be adjusted so that they appear in
|
||
|
the timezone of the user (as determined by the \fITZ\fP
|
||
|
variable).
|
||
|
.LP
|
||
|
Neither this, nor warning messages concerning the selection of the
|
||
|
command interpreter, are considered a diagnostic that changes
|
||
|
the exit status.
|
||
|
.LP
|
||
|
Diagnostic messages, if any, shall be written to standard error.
|
||
|
.SH OUTPUT FILES
|
||
|
.LP
|
||
|
None.
|
||
|
.SH EXTENDED DESCRIPTION
|
||
|
.LP
|
||
|
None.
|
||
|
.SH EXIT STATUS
|
||
|
.LP
|
||
|
The following exit values shall be returned:
|
||
|
.TP 7
|
||
|
\ 0
|
||
|
Successful completion.
|
||
|
.TP 7
|
||
|
>0
|
||
|
An error occurred.
|
||
|
.sp
|
||
|
.SH CONSEQUENCES OF ERRORS
|
||
|
.LP
|
||
|
The job shall not be scheduled.
|
||
|
.LP
|
||
|
\fIThe following sections are informative.\fP
|
||
|
.SH APPLICATION USAGE
|
||
|
.LP
|
||
|
It may be useful to redirect standard output within the specified
|
||
|
commands.
|
||
|
.SH EXAMPLES
|
||
|
.IP " 1." 4
|
||
|
This sequence can be used at a terminal:
|
||
|
.sp
|
||
|
.RS
|
||
|
.nf
|
||
|
|
||
|
\fBbatch
|
||
|
sort < file >outfile
|
||
|
EOT
|
||
|
\fP
|
||
|
.fi
|
||
|
.RE
|
||
|
.LP
|
||
|
.IP " 2." 4
|
||
|
This sequence, which demonstrates redirecting standard error to a
|
||
|
pipe, is useful in a command procedure (the sequence of output
|
||
|
redirection specifications is significant):
|
||
|
.sp
|
||
|
.RS
|
||
|
.nf
|
||
|
|
||
|
\fBbatch <<
|
||
|
! diff file1 file2 2>&1 >outfile | mailx mygroup
|
||
|
!
|
||
|
\fP
|
||
|
.fi
|
||
|
.RE
|
||
|
.LP
|
||
|
.SH RATIONALE
|
||
|
.LP
|
||
|
Early proposals described \fIbatch\fP in a manner totally separated
|
||
|
from \fIat\fP, even
|
||
|
though the historical model treated it almost as a synonym for \fIat\fP
|
||
|
\fB-qb\fP. A number of
|
||
|
features were added to list and control batch work separately from
|
||
|
those in \fIat\fP. Upon
|
||
|
further reflection, it was decided that the benefit of this did not
|
||
|
merit the change to the historical interface.
|
||
|
.LP
|
||
|
The \fB-m\fP option was included on the equivalent \fIat\fP command
|
||
|
because it is
|
||
|
historical practice to mail results to the submitter, even if all
|
||
|
job-produced output is redirected. As explained in the RATIONALE
|
||
|
for \fIat\fP, the \fBnow\fP keyword submits the job for immediate
|
||
|
execution (after scheduling
|
||
|
delays), despite some historical systems where \fIat\fP \fBnow\fP
|
||
|
would have been considered
|
||
|
an error.
|
||
|
.SH FUTURE DIRECTIONS
|
||
|
.LP
|
||
|
None.
|
||
|
.SH SEE ALSO
|
||
|
.LP
|
||
|
\fIat\fP
|
||
|
.SH COPYRIGHT
|
||
|
Portions of this text are reprinted and reproduced in electronic form
|
||
|
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
|
||
|
-- Portable Operating System Interface (POSIX), The Open Group Base
|
||
|
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
|
||
|
Electrical and Electronics Engineers, Inc and The Open Group. In the
|
||
|
event of any discrepancy between this version and the original IEEE and
|
||
|
The Open Group Standard, the original IEEE and The Open Group Standard
|
||
|
is the referee document. The original Standard can be obtained online at
|
||
|
http://www.opengroup.org/unix/online.html .
|