Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [at]

A utility used for scheduling an event to happen once at some point in the future.

The at utility reads commands from standard input and group them together as an at-job, to be executed at a later time.

External reference

at specification (The Open Group Base Specifications Issue 7, 2018 edition)

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Remove all `at` jobs

I know that to remove a scheduled at job I have to use atrm "numjob1 numjob2", but is there an easy way to do that for all the jobs?
robob
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Why do we need the "at" command in Linux?

I was studying code in which the at command is used. I looked around and found that it is used to execute batch jobs. It is used to schedule jobs. It is given, as its input, a command, and a time, relative or absolute. So, my first question is: why…
Akshay Patil
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What is the difference between shutdown 18:00 and at 18:00 shutdown?

at 18:00 shutdown now and shutdown 18:00 , are they starting the same service? Do they work the same way?
yang
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Does `at` run a command later if the computer is off at the specified time?

I want to schedule jobs with at, but I'm not sure what happens if the computer is suspended at the specified time: Will the command be executed as soon as the computer wakes up again (like with anacron) or will it not be executed at all (like with…
dessert
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Why does this 'at' command not print to the standard output?

I am a relative Linux novice. I am trying to learn how to use at so that I can schedule tasks to begin at a later time, without using sleep. I have been looking at this previous question for help. My question is, in the following sample bash…
Andrew
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Where does the output of `at` and `cron` jobs go?

Where does standard output from at and cron tasks go, given there is no screen to display to? It's not appearing in the directory the jobs were started from, nor in my home directory. How could I actually figure this out given that I don't know how…
Michael Durrant
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Why does `at` warn me that commands will be executed using /bin/sh? What if I want a different shell?

I tried to use at from within a script of mine and it prints: warning: commands will be executed using /bin/sh How would I use different shell if I wanted?
Cratylus
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Making "at" work on macOS

I am working on a CentOS server and schedule a task with command at # echo "touch a_long_file_name_file.txt" | at now + 1 minute job 2 at Wed Oct 31 13:52:00 2018 One minute later, # ls | grep a_long_file_name_file.tx a_long_file_name_file.txt the…
AbstProcDo
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Why does the echo command do not work with at command?

when I type: at now + 1 min at>play /usr/share/sounds/startrek.wav at>ctrl+d it works, so after one minute there is actually a sound played. but, when I type: at now + 1 min at>echo "Teresa the green vegetable lover" at>ctrl+d I got no error…
Abdul Al Hazred
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How does `at` know there will be a time change?

I happened to be twiddling around with at just yesterday at 2:40 AM. (Don't ask...) I tried scheduling events one minute in the future (as a test), and – it just didn't happen. The events were in the queue allright, but they just stayed there when…
leftaroundabout
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at some time from now do something (and maybe also show result in console)

I use Ubuntu server 16.04 and I desire to use the utility at in my current session to do something 1 minute from now (say, an echo), without giving a specific date and time - just 1 minute ahead from current time. This failed: echo 'hi' | at 1m The…
Arcticooling
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sort at jobs chronologically

Possibly a simple solution I misplaced. How can I get the output of atq sorted chronologically, so I can easily see who's due to run next? The man page for sort doesn't have anything built-in to recognize timestamps like the following: atq 1264 …
Marcos
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How do I send postponed mail at a later time with Mutt?

I don't like waking up early but people prefer to be emailed in the morning rather than at 3AM. Therefore I often use at to send the email whilst I'm asleep. But that comes with the complication that I need to write the email as a text file and send…
grochmal
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at command: Garbled time

I am not able to run at command. edward@ArchLinux:~$ at Garbled time what is wrong? Am I running it wrong?
Alex Jones
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Does at scheduled tasks remain after reboot?

I'm using at to schedule a task for a later time. Will it survive a reboot, or should I re-assign all the tasks after reboot ?
Asaf Nevo
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