The at Command

The at facility submits a command line (or a script) for execution at an arbitrary later time. It has the form:

% at options time < scriptfile

This submits the scriptfile for execution at a later time. The redirection (<) isn't required on BSD and some other UNIX systems. If you don't want to write a script, you can omit it and type your commands on the terminal, terminated by CTRL-d:

% at options time Command 1 Command 2 ... [CTRL-d]

The time is most commonly a four-digit number representing a time on a 24-hour clock. For example, represents 1:30 a.m. and represents 2 p.m. You can also use abbreviations such as am, pm, and so on.

- ML from Anonymous' System Performance Tuning, Chapter 3