linux man page for batch

BATCH(P)						     POSIX Programmer's Manual							  BATCH(P)

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 /usr/lib/cron/at.allow. If that file does not exist, the file
       /usr/lib/cron/at.deny shall be checked to determine whether the user shall be denied access to batch.   If  neither  file  exists,  only  a
       process	with  the appropriate privileges shall be allowed to submit a job. If only at.deny exists and is empty, global usage shall be per-
       mitted. 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 Shell Command Language
       .

INPUT FILES
       The  text  files  /usr/lib/cron/at.allow  and  /usr/lib/cron/at.deny 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
	      IEEE Std 1003.1-2001,  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  time-
	      zone  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
", 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  redi-
	   rection 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.

SEE ALSO
       at

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
       ogy -- 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 .

IEEE
/The Open Group						       2003								  BATCH(P)