Linux 'at' Command

The at command in Linux is used to schedule a command or script to run at a specific time in the future. It is a powerful tool for task scheduling.

Options

-f: Specifies a file containing the commands to be executed.
-m: Sends an email to the user after the job is completed, even if there is no output.
-v: Displays the time the job is scheduled to run.
-l: Lists the user's pending jobs (same as atq).
-d: Deletes a job by its job number (same as atrm).
-q: Specifies the queue to use (default is a).
-t: Specifies the time in the format [[CC]YY]MMDDhhmm[.ss] to run the job.
-c: Displays the contents of a job.
--help: Displays help information for the at command.
--version: Displays the version of the at command.

To schedule a command to run at 3:00 PM:

echo "ls -l" | at 3:00 PM

To schedule a script stored in a file:

at -f myscript.sh 5:00 PM

To view all scheduled jobs:

at -l

To remove a job with job number 2:

at -d 2

To remove a job with job number 2:

atrm 2

To schedule a command and receive an email notification:

echo "df -h" | at -m 6:00 PM

To schedule a command to run 10 minutes from now:

echo "echo 'Hello, World!'" | at now + 10 minutes

To schedule a command to run on the first day of next month at 8:00 AM:

echo "echo 'New month started!'" | at 8:00 AM next month

To schedule a command to run tomorrow at 9:00 AM:

echo "echo 'Good morning!'" | at 9:00 AM tomorrow

To schedule a command to run in one week at 10:00 AM:

echo "echo 'One week later!'" | at 10:00 AM + 1 week

echo "echo 'One week later!'" | at 10:00 AM + 2 week

To schedule a command to run in one year at 11:00 AM:

echo "echo 'One year later!'" | at 11:00 AM + 1 year

The at command requires the atd daemon to be running on your system. Ensure it is enabled and started before using the at command.