at,  batch,  atq,  atrm  -  queue,  examine  or  delete  jobs for later


   at [-V] [-q queue] [-f file] [-mMlv] timespec...
   at [-V] [-q queue] [-f file] [-mMkv] [-t time]
   at -c job [job...]
   atq [-V] [-q queue]
   at [-rd] job [job...]
   atrm [-V] job [job...]
   at -b


   at and batch read commands from standard  input  or  a  specified  file
   which are to be executed at a later time, using /bin/sh.

   at      executes commands at a specified time.

   atq     lists   the  user's  pending  jobs,  unless  the  user  is  the
           superuser; in that case,  everybody's  jobs  are  listed.   The
           format  of  the output lines (one for each job) is: Job number,
           date, hour, queue, and username.

   atrm    deletes jobs, identified by their job number.

   batch   executes commands when system  load  levels  permit;  in  other
           words,  when  the  load  average  drops below 1.5, or the value
           specified in the invocation of atd.

   At allows fairly complex time  specifications,  extending  the  POSIX.2
   standard.   It  accepts  times  of  the  form  HH:MM  to run a job at a
   specific time of day.  (If that time is already past, the next  day  is
   assumed.)   You  may  also specify midnight, noon, or teatime (4pm) and
   you can have a time-of-day suffixed with AM or PM for  running  in  the
   morning or the evening.  You can also say what day the job will be run,
   by giving a date in the form month-name day with an optional  year,  or
   giving  a  date  of  the form MMDD[CC]YY, MM/DD/[CC]YY, DD.MM.[CC]YY or
   [CC]YY-MM-DD.   The  specification  of   a   date   must   follow   the
   specification  of  the time of day.  You can also give times like now +
   count time-units, where the time-units can be minutes, hours, days,  or
   weeks  and  you  can tell at to run the job today by suffixing the time
   with today and to run the job  tomorrow  by  suffixing  the  time  with

   For  example,  to run a job at 4pm three days from now, you would do at
   4pm + 3 days, to run a job at 10:00am on July 31, you would do at  10am
   Jul 31 and to run a job at 1am tomorrow, you would do at 1am tomorrow.

   If  you  specify a job to absolutely run at a specific time and date in
   the past, the job will run as soon as possible.  For example, if it  is
   8pm and you do a at 6pm today, it will run more likely at 8:05pm.

   The   definition   of   the   time   specification   can  be  found  in

   For both at and batch, commands are read from  standard  input  or  the
   file specified with the -f option and executed.  The working directory,
   the environment (except for the variables BASH_VERSINFO, DISPLAY, EUID,
   GROUPS,  SHELLOPTS,  TERM,  UID, and _) and the umask are retained from
   the time of invocation.

   As at is currently implemented as a setuid program,  other  environment
   variables  (e.g.  LD_LIBRARY_PATH or LD_PRELOAD) are also not exported.
   This may change in the future.  As a workaround,  set  these  variables
   explicitly in your job.

   An  at  - or batch - command invoked from a su(1) shell will retain the
   current userid.  The user will be mailed standard  error  and  standard
   output  from his commands, if any.  Mail will be sent using the command
   /usr/sbin/sendmail.  If at is executed from a su(1) shell, the owner of
   the login shell will receive the mail.

   The  superuser  may  use  these commands in any case.  For other users,
   permission to use at is  determined  by  the  files  /etc/at.allow  and
   /etc/at.deny.  See at.allow(5) for details.


   -V      prints   the   version   number  to  standard  error  and  exit

   -q queue
           uses the specified queue.  A queue designation  consists  of  a
           single letter; valid queue designations range from a to z and A
           to Z.  The a queue is the default for at and the  b  queue  for
           batch.  Queues with higher letters run with increased niceness.
           The special queue "=" is reserved for jobs which are  currently

   If  a  job is submitted to a queue designated with an uppercase letter,
   the job is treated as if it were submitted to batch at the time of  the
   job.  Once the time is reached, the batch processing rules with respect
   to load average apply.  If atq is given a specific queue, it will  only
   show jobs pending in that queue.

   -m      Send  mail to the user when the job has completed even if there
           was no output.

   -M      Never send mail to the user.

   -f file Reads the job from file rather than standard input.

   -t time run the job at time, given in the format [[CC]YY]MMDDhhmm[.ss]

   -l      Is an alias for atq.

   -r      Is an alias for atrm.

   -d      Is an alias for atrm.

   -b      is an alias for batch.

   -v      Shows the time the job will be executed before reading the job.

   Times displayed will be in the format "Thu Feb 20 14:50:00 1997".

   -c     cats the jobs listed on the command line to standard output.




   at.allow(5), at.deny(5), atd(8), cron(1), nice(1), sh(1), umask(2).


   The correct operation of batch for Linux depends on the presence  of  a
   proc- type directory mounted on /proc.

   If the file /var/run/utmp is not available or corrupted, or if the user
   is not logged on at the time at is invoked, the mail  is  sent  to  the
   userid found in the environment variable LOGNAME.  If that is undefined
   or empty, the current userid is assumed.

   At and batch as presently implemented are not suitable when  users  are
   competing  for resources.  If this is the case for your site, you might
   want to consider another batch system, such as nqs.


   At was mostly written by Thomas Koenig,

                              2009-11-14                             AT(1)


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