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**The traditional way on a \*nix system to run a command at some future time is `at`.**

    $ at 'now + 10 minutes'
    at Wed Aug 23 19:00:00 2023
    at> date >> ~/current-time
    at> ^D
    job NNN at Wed Aug 23 19:00:00 2023
    $

You can also specify a particular time, which will be interpreted as "next time the real time is X":

    $ at '16:00'
    at Wed Aug 24 16:00:00 2023
    ...

or a date and time, although the syntax is a little peculiar:

    $ at '22:00 Aug 29'
    at Tue Aug 29 22:00:00 2023
    ...
    $ at '22:00 Jul 29'
    at Mon Jul 29 22:00:00 2024
    ...
    $ at '22:00 Jul 29 2025'
    at Tue Jul 29 22:00:00 2025
    ...

Normally, after the job finishes executing, any output (stdout or stderr) will be delivered in an email to the account which scheduled the job.

I do believe that most `at` implementations will start executing the job *as soon as the specified time has occurred*. So if the system is powered off, or `atd` otherwise isn't running, at the specified time, the job will execute the next time `atd` is started.

At least on a typical Debian system, it's also possible to pipe a command into `at` to schedule it; for example:

    $ echo date | at 'now + 10 minutes'

will run `date` after approximately ten minutes.

To see which jobs are queued for execution, use `atq`. To see what a job will do when it is executed, use `at -c $JOBID`. To delete a job, use `atrm $JOBID`.