Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
AT(1)			FreeBSD	General	Commands Manual			 AT(1)

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

     at	[-V] [-q queue]	[-f file] [-mldbv] time

     at	[-V] -c	job [job ...]

     atq [-V] [-q queue] [-v]

     atrm [-V] job [job	...]

     batch [-V]	[-q queue] [-f file] [-mv] [time]

     at, AT&T UNIX and batch read commands from	standard input or a specified
     file which	are to be executed at a	later time, using sh(1).

     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;

     atrm    deletes jobs;

     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 atrun.

     at, AT&T UNIX allows some moderately complex time specifications.	It
     accepts times of the form HHMM or 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 MMDDYY or MM/DD/YY or	DD.MM.YY.  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 suffix-
     ing the time with today and to run	the job	tomorrow by suffixing the time
     with tomorrow.

     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.

     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 TERM, TERMCAP, DISPLAY and _) and
     the umask are retained from the time of invocation.  An at	or batch com-
     mand 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 sendmail(8).  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, per-
     mission to	use at is determined by	the files /var/at/at.allow and

     If	the file /var/at/at.allow exists, only usernames mentioned in it are
     allowed to	use at.

     If	/var/at/at.allow does not exist, /var/at/at.deny is checked, every
     username not mentioned in it is then allowed to use at.

     If	neither	exists,	only the superuser is allowed use of at.  This is the
     default configuration.

     An	empty /var/at/at.deny means that every user is allowed use these com-

     -V	     prints the	version	number to standard error.

     -q	queue
	     uses the specified	queue.	A queue	designation consists of	a sin-
	     gle letter; valid queue designations range	from a to z.  and A to
	     Z.	 The c queue is	the default for	at and the E queue for batch.
	     Queues with higher	letters	run with increased niceness.  If a job
	     is	submitted to a queue designated	with an	uppercase letter, it
	     is	treated	as if it had been submitted to batch at	that time.  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.

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

     -l	     Is	an alias for atq.

     -d	     Is	an alias for atrm.

     -b	     Is	an alias for batch.

     -v	     For atq, shows completed but not yet deleted jobs in the queue;
	     otherwise shows the time the job will be executed.

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

     /var/at/jobs	     Directory containing job files
     /var/at/spool	     Directory containing output spool files
     /var/run/utmp	     Login records
     /var/at/at.allow	     Allow permission control
     /var/at/at.deny	     Deny permission control
     /var/at/jobs/.lockfile  Job-creation lock file.

     cron(8), nice(1), umask(2), sh(1),	sendmail(8), atrun(8).

     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, AT&T UNIX 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 <>.	 The
     time parsing routines are by
     David Parsons <>.

FreeBSD	2.1			April 12, 1995			   FreeBSD 2.1


Want to link to this manual page? Use this URL:

home | help