at / atq / atrm

Updated

July 31, 2026

Overview

at schedules one-shot jobs for a later time. Recurring work belongs in cron or systemd timers. Requires the atd daemon.

Syntax

at [options] TIME
at -f script TIME
atq
atrm id...
batch

Time expressions

Examples: now + 5 minutes, 23:30, midnight, noon tomorrow, 4pm + 2 days, teatime.

Examples with Explanations

Interactive

at now + 10 minutes
# type commands, finish with Ctrl-D

From pipe / file

echo '/usr/local/bin/backup.sh >> /var/log/backup.at.log 2>&1' | at 02:30
at -f ./job.sh midnight

Queue management

atq
at -c 3          # show job body
atrm 3

Low-load batch queue

echo './heavy.sh' | batch

Permissions & service

systemctl status atd
# /etc/at.allow  /etc/at.deny

Output

Job stdout/stderr is mailed to the user if a local MTA exists; otherwise redirect inside the job.