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PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

NAME

       batch — schedule commands to be executed in a batch queue

SYNOPSIS

       batch

DESCRIPTION

       The  batch  utility  shall  read  commands from standard input and schedule them for execution in a batch
       queue. It shall be the equivalent of the command:

           at -q b -m now

       where queue b is a special at 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 batch.

       Users shall be permitted to use batch if their name appears in the file at.allow which is located  in  an
       implementation-defined  directory.  If that file does not exist, the file at.deny, which is located in an
       implementation-defined directory, shall be checked to determine whether the user shall be  denied  access
       to  batch.  If neither file exists, only a process with appropriate privileges shall be allowed to submit
       a job. If only at.deny exists and is empty, global usage shall be permitted.  The  at.allow  and  at.deny
       files shall consist of one user name per line.

OPTIONS

       None.

OPERANDS

       None.

STDIN

       The  standard  input shall be a text file consisting of commands acceptable to the shell command language
       described in Chapter 2, Shell Command Language.

INPUT FILES

       The text files at.allow and at.deny, which are located  in  an  implementation-defined  directory,  shall
       contain  zero  or  more  user  names,  one per line, of users who are, respectively, authorized or denied
       access to the at and batch utilities.

ENVIRONMENT VARIABLES

The following environment variables shall affect the execution of batch:

LANG Provide a default value for the internationalization variables that are unset or null. (See the
Base Definitions volume of POSIX.1‐2017, Section 8.2, Internationalization Variables for the
precedence of internationalization variables used to determine the values of locale
categories.)

LC_ALL If set to a non-empty string value, override the values of all the other internationalization
variables.

LC_CTYPE 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).

LC_MESSAGES
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.

LC_TIME Determine the format and contents for date and time strings written by batch.

NLSPATH Determine the location of message catalogs for the processing of LC_MESSAGES.

SHELL Determine the name of a command interpreter to be used to invoke the at-job. If the variable is
unset or null, sh shall be used. If it is set to a value other than a name for sh, the
implementation shall do one of the following: use that shell; use sh; use the login shell from
the user database; any of the preceding accompanied by a warning diagnostic about which was
chosen.

TZ Determine the timezone. The job shall be submitted for execution at the time specified by
timespec or -t time relative to the timezone specified by the TZ variable. If timespec
specifies a timezone, it overrides TZ. If timespec does not specify a timezone and TZ is unset
or null, an unspecified default timezone shall be used.

ASYNCHRONOUS EVENTS

       Default.

STDOUT

       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.

STDERR

       The following shall be written to standard error when a job has been successfully submitted:

           "job %s at %s\n", at_job_id, <date>

       where date shall be equivalent in format to the output of:

           date +"%a %b %e %T %Y"

       The  date  and  time  written  shall  be  adjusted  so  that  they appear in the timezone of the user (as
       determined by the TZ variable).

       Neither this, nor warning messages concerning the selection of the command interpreter, are considered  a
       diagnostic that changes the exit status.

       Diagnostic messages, if any, shall be written to standard error.

OUTPUT FILES

       None.

EXTENDED DESCRIPTION

       None.

EXIT STATUS

       The following exit values shall be returned:

        0    Successful completion.

       >0    An error occurred.

CONSEQUENCES OF ERRORS

       The job shall not be scheduled.

       The following sections are informative.

APPLICATION USAGE

       It may be useful to redirect standard output within the specified commands.

EXAMPLES

        1. This sequence can be used at a terminal:

               batch
               sort < file >outfile
               EOT

        2. This  sequence,  which  demonstrates  redirecting  standard  error  to a pipe, is useful in a command
           procedure (the sequence of output redirection specifications is significant):

               batch <<!
               diff file1 file2 2>&1 >outfile | mailx mygroup
               !

RATIONALE

       Early proposals described batch in a manner totally separated from at, even though the  historical  model
       treated  it  almost  as  a synonym for at -qb.  A number of features were added to list and control batch
       work separately from those in at.  Upon further reflection, it was decided that the benefit of  this  did
       not merit the change to the historical interface.

       The -m option was included on the equivalent at 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 at,
       the now keyword submits  the  job  for  immediate  execution  (after  scheduling  delays),  despite  some
       historical systems where at now would have been considered an error.

FUTURE DIRECTIONS

       None.

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
       for  Information  Technology  --  Portable  Operating  System  Interface  (POSIX),  The  Open  Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 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 .

       Any typographical or formatting errors that appear in this page are most likely to have  been  introduced
       during   the   conversion  of  the  source  files  to  man  page  format.  To  report  such  errors,  see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2017                                         BATCH(1POSIX)