at, atq and atrm

Manage jobs for later execution

at    [-V] [-q Q] [-f file] [-mldbv] { time | -t time_arg}
batch [-V] [-q Q] [-f file] [-mv] [time]

at -c job [job…]
atq [-V] [-q queue]
atrm [-V] job [job…]


at and batch read commands from standard input or a specified file to be executed at a later time .

at timespec	executes commands at a specified time. > at now + 20 minutes -f checkdaily
batch	executes commands when system load average drops below 0.8, or the value specified in the invocation of atrun.
atq	displays jobs in the queue. % atq 1 Fri Sep 16 11:24:00 2022 For the superuser all jobs are listed in the format: Job number, date, hour, job class.
atrm job [ job … ]	remove jobs, by job number.
 atrun	run by launchd periodically, if previously loaded by superuser via: launchctl load -w /System/Library/LaunchDaemons/com.apple.atrun.plist: Dict { ProgramArguments = Array { /usr/libexec/atrun } StartInterval = 30 Label = com.apple.atrun Disabled = true }

-q queue	use queue, a single letter [a-zA-Z]. for running jobs: = . Defaults: a for at and b for batch. Queues with higher letters run with increased niceness. A job is submitted to a queue with an uppercase letter is treated as if it had been submitted to batch at that time. For atq, only show jobs pending in that queue are shown.
-f file	Reads the job comands from file rather than standard input.
-m	mail is always sent when the job completes
-l	at -l list queue.
-d job	at -d delete jobs from queue
-v	Shows the time verbosly the job will be executed. in the format "1997-02-20 14:50" unless the environment variable POSIXLY_CORRECT is set; then, it will be "Thu Feb 20 14:50:00 1997".
-c	cats the jobs listed on the command line to standard output.
-t time_arg	the job is to be run at the time specified in the same format as specified for the touch(1) ([[CC]YY]MMDDhhmm).
-V	prints the version number to standard error.

Time specifications^†

• midnight, noon, or teatime (4pm)
  
• now [+ n ] minutes, hours, days, or weeks or
  
• HH:MM[AM|PM]

A date may follow the time.

• MMDDYY or MM/DD/YY or DD.MM.YY.
• month-name day [year], or
• today or tomorrow.

For example,:
• 4pm three days from now, use 4pm + 3 days
• 10:00am on July 31, use 10am Jul 31
• 1am tomorrow, use 1am tomorrow.

The working directory, the environment (except for $TERM, $DISPLAY and _) and umask are retained from the time of invocation.
A job invoked from a su shell retains the current userid.
The user will be mailed standard error and standard output using /usr/sbin/sendmail.
If at is executed from a su shell, the owner of the login shell will receive the mail.

For other users:
If /etc/at.allow exists, only usernames in it are allowed to use at.
If /etc/at.allow does not exist,
   /etc/at.deny is checked, every username not mentioned in it
If neither exists, only the superuser is allowed use of at.
If /etc/at.denys is empty every user is allowed use these commands, default .

ENVIRONMENT

    /var/spool/at /var/spool/at/spool
       /var/run/utmp
       /proc/loadavg
       /etc/at.allow /etc/at.deny

Made true HTML and terse by Dennis German