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at(1)									at(1)



NAME

  at, batch - Runs commands at a later time

SYNOPSIS

  at [-c  | -s	| -k] [-m] [-f file] [-q queuename] time [date]	[+increment]
  [command | file]...

  at [-c  | -s	| -k] [-m] [-f file] [-q queuename] -t	[[cc]yy] MMddhhmm
  [.ss]

  at -l	 -o  [-q queuename] [user...]

  at -l	 [job_number]

  at -r	 [-Fi] job_number... | [-u user]

  at -n	 [user]

  batch

  The at and batch commands read from standard input or	accept as arguments
  the names of commands	to be run at a later time.  The	at command lets	you
  specify when the commands are	to be run.  The	batch command runs jobs	when
  the system load level	permits.

STANDARDS

  Interfaces documented	on this	reference page conform to industry standards
  as follows:

  at: XCU5.0

  batch: XCU5.0

  Refer	to the standards(5) reference page for more information	about indus-
  try standards	and associated tags.

OPTIONS

  -c  [Tru64 UNIX]  Requests that csh be used for executing this job.

  -f file
      Specifies	the name of the	file to	use instead of stdin.  The specified
      file contains the	list of	commands to be executed.

  -F  [Tru64 UNIX]  Suppresses delete verification.

  -i  [Tru64 UNIX]  Specifies interactive delete.

  -k  [Tru64 UNIX]  Requests that ksh be used for executing this job.

  -l [user ...]
      Reports your scheduled jobs.

      [Tru64 UNIX]  If the root	user issues the	command	with this option, all
      of the queued at commands	are listed with	the name of the	user who
      issued each one.	The root user can also request a report	of scheduled
      jobs for the specified user only.

  -m  Mails a message about the	successful execution of	the command.  Stan-
      dard output and standard error are also mailed if	they are generated
      and are not redirected.  This is the default for standard	output and
      standard error.  Without the -m option, there is no notification of job
      completion, and no mail if standard output and standard error were not
      generated.

  -n [user]
      [Tru64 UNIX]  Requests the number	of files in the	queue for the current
      user.  The root user can specify a different user	with the user argu-
      ment.

  -o  [Tru64 UNIX]  Lists jobs in scheduled order.  This option	is useful
      only when	used with the -l option.

  -q queuename
      Specifies	the queue you want to use.  When used with the -l option,
      limits the search	to the specified queue.

      Values for queuename are limited to the lower case letters a through z.
      By default, at jobs are scheduled	in queue a and batch jobs are
      scheduled	in queue b. Since queue	c is reserved for cron jobs, it	can
      not be used with the -q option.

  -r job_number	...
      Removes a	job previously scheduled by at or batch, where job_number is
      the number assigned by at	or batch.  If you do not have root user
      authority, you can remove	only your own jobs.  The atrm command is
      available	to the root user to remove jobs	issued by other	users or all
      jobs issued by a specific	user.  This option can be used in combination
      with the -i, -f, and -u options.

  -s  [Tru64 UNIX]  Requests that the Bourne shell be used for executing this
      job (default).

  -t time
      [Tru64 UNIX]  Submits the	job to be run at the specified time.  (See
      the SYNOPSIS section for the correct time	format.)

  -u user
      Deletes all jobs for the specified user.	This option must be used with
      the -r option as follows:
	   at -r -u user



OPERANDS

  [Tru64 UNIX]	The operands associated	with the at command specify the	time
  at which the job should be run.  They	are described in the section Specify-
  ing a	Time and Date.








DESCRIPTION

  Both at and batch mail you the standard output and standard error from the
  scheduled commands, unless you redirect that output.	They also write	the
  job number and the scheduled time to standard	error.

  If a filename	specified on an	at command line	is executable (that is,	has
  the x	permission for the user	in question), at assumes that it is a command
  and the job consists of this command only.  If the file is not executable,
  at assumes that you want its contents	to be the instructions for the job
  (same	as BSD at).

  [Tru64 UNIX]	If at cannot find the file at all, the specification is
  passed to the	date parser.  If the specification is not recognized by	the
  date parser, the user	receives the error Unknown word.

  [Tru64 UNIX]	The at command defaults	to the Bourne shell.  Use the -c
  option to specify the	C shell, or the	-k option to specify the Korn shell.
  Variables in the shell environment, the current directory, umask, and
  ulimit are retained when the commands	run. The value of SHELL	is set to be
  consistent with the shell actually used. Open	file descriptors, traps, and
  priority are lost.

  You can use at if your login name appears in the /usr/lib/cron/at.allow
  file,	if that	file exists, or	if there is no at.allow	file and your name is
  not in the /usr/lib/cron/at.deny file.  The at.allow and at.deny files con-
  tain one user	name per line. Note that /usr/lib/cron is symbolically linked
  to /var/adm/cron.

  If neither the at.allow nor the at.deny file exists, only someone with root
  user authority can submit a job.

  To allow global access to at,	the system administrator can remove the
  at.allow file	and create a zero-length at.deny file.

  Specifying a Time and	Date


  You must specify a time argument with	these commands.	 You can specify
  optionally the date argument.	These arguments	are affected when the DATEMSK
  environment variable is set.	The next subsection describes the effect of
  this environment variable.

  The required time argument can be one	of the following:

   1.  A number	followed by an optional	suffix.	 The at	command	interprets 1-
       and 2-digit numbers as hours.  It interprets 4 digits as	hours and
       minutes.	 The LC_TIME environment variable specifies the	order of
       hours and minutes.  The default order is	the hour followed by the
       minute.	You can	also separate hours and	minutes	with a : (colon).
       The default order is hour:minute.  In addition, you can specify a suf-
       fix of am, pm, or zulu.	If you do not specify am or pm,	at uses	a
       24-hour clock. The suffix zulu indicates	that the time is UTC (Coordi-
       nated Universal Time).

   2.  The at command also recognizes the following keywords as	special
       times: noon, midnight, now, A for a.m., P for p.m., N for noon, and M
       for midnight.  The time argument	specifies a time in the	future.	 For
       example,	if the current time is 9:02 p.m., and you specify a time of
       9P, the command is executed at 9	p.m. the next day.  However, if	the
       current time is 8:58 p.m. and you specify 9P, the command is executed
       in two minutes.	The LC_TIME environment	variable controls the key-
       words that at recognizes.   Keywords are	defined	on a locale basis.


  You can specify the date argument as either a	month name and a day number
  (and possibly	a year number preceded by a comma), or a day of	the week.
  The LC_TIME environment variable specifies the order of the month name and
  day number (by default, month	followed by day).  The at command recognizes
  two special days, today and tomorrow by default.  The	special	day today is
  the default date if the specified time is later than the current hour; the
  special day tomorrow is the default if the time is earlier than the current
  hour.	 If the	specified month	is less	than the current month (and a year is
  not given), next year	is the default year.

  The optional increment can be	one of the following:

    +  A + (plus sign) followed	by a number and	one of the following words:
       minute[s], hour[s], day[s], week[s], month[s], year[s] (or their
       locale specific equivalents).

    +  The special word	next followed by one of	the following words:
       minute[s], hour[s], day[s], week[s], month[s], year[s] (or their	local
       specific	equivalents).

  Job numbers are specified as follows:

  user.xxxxxxxxx.y

  [Tru64 UNIX]	The user argument identifies the user who scheduled the	job;
  xxxxxxxxx is a 9-digit number	(encoded time for the job); and	y indicates
  the job type or queue	name as	follows:

  Argument   Job Type
  a	     at	job
  b	     batch job
  e	     ksh job
  f	     csh job

  Setting the DATEMSK Environment Variable


  [Tru64 UNIX]	If the DATEMSK environment variable is set, it points to a
  template file	that the at command uses to determine the valid	time and date
  arguments instead of the values described in the previous section.  Specif-
  ically, noon,	midnight, now, next, today, tomorrow, and increment are	not
  recognized when the DATEMSK environment variable is set.

  [Tru64 UNIX]	The entries in the template file used by the DATEMSK environ-
  ment variable	provide	an expansive set of date formats available in dif-
  ferent languages depending on	the setting of the environment variable	LANG
  or LC_TIME.  The setlocale(3)	reference page contains	the list of field
  descriptors allowed in the template file.  This list is a sublist of the
  field	descriptors supported by the calendar command which are	listed on the
  date(1) reference page.

EXIT STATUS

  The following	exit values are	returned:

  0   The at command successfully submitted, removed, or listed	all specified
      jobs.

  >>0  An error occurred.








EXAMPLES

   1.  To schedule a command from a terminal, enter a command similar to one
       of the following:
	    at 5 pm Friday uuclean
	    at now next	week uuclean
	    at now + 2 days uuclean

       The preceding commands can be scheduled as shown	only if	uuclean	is in
       the current directory.

   2.  To run uuclean at 3:00 in the afternoon on January 24, enter any	one
       of the following	commands:
	    echo  uuclean  |  at  3:00	pm  January  24
	    echo  uuclean  |  at  3pm  Jan  24
	    echo  uuclean  |  at  1500	jan  24

   3.  To list the jobs	you have sent to be run	later, enter:
	    at -l

   4.  To cancel jobs, enter:
	    at -r julie.586748399.a

       This cancels job	julie.586748399.  Use at -l to list the	job numbers
       assigned	to your	jobs.

   5.  To execute a command when the system load level permits,	enter:
	    batch
	    nroff infile >> outfile
	    <&lt;Ctrl-d>&gt;

       where <&lt;Ctrl-d>&gt; is the End-of-File character.

   6.  Assume  a template file,	/var/tmp/AT.TEMPL, contains the	following:


	    %I %p, the %est of %B of the %Y run	the following job
	    %I %p, the %end of %B of the %Y run	the following job
	    %I %p, the %erd of %B of the %Y run	the following job
	    %I %p, the %eth of %B of the %Y run	the following job
	    %d/%m/%y
	    %H:%M:%S
	    %I:%M%p

       To invoke the at	command	when the DATEMSK environment variable is set
       to /var/tmp/AT.TEMPL, and the template file any of the following	are
       valid:
	    at 2 pm, the 3rd of	July of	the year 2000 run the following	job
	    at 3/4/99
	    at 10:30:30
	    at 2:30pm



FILES

  /var/adm/cron
      Main cron	directory

  /var/adm/cron/at.allow
      List of allowed users

  /var/adm/cron/at.deny
      List of denied users

  /var/spool/cron/atjobs
      Spool area

  /var/adm/cron/log
      History information for cron

  /var/adm/cron/queuedefs
      Queue description	file for at, batch, and	cron

SEE ALSO

  Commands:  atq(1), atrm(1), calendar(1), csh(1), cron(8), date(1), kill(1),
  mail(1), binmail(1), ksh(1), mailx(1), Mail(1), nice(1), ps(1), Bourne
  shell	sh(1b),	POSIX shell sh(1p)

  Functions:  setlocale(3)

  Standards:  standards(5)

  Files:  queuedefs(4)

  System Administration

  Network Administration: Services

  Command and Shell User's Guide