Batch processing is a term that mainframe programmers used to use to refer to scheduled jobs. Batch processing is a form of automation, since the scheduled jobs must be able to execute without human interaction. Automation is fun, and is quite useful even in today’s post-mainframe world. While setting up automated tasks is time-consuming, the goal is to save time in the long run since you can reuse the commands you told the computer to perform.
at(1) is a program useful for scheduling a single job for execution. It is incredibly simple and can be quite useful in a pinch.
Say I wanted to run a one-time build of some software overnight.
$ at 10pm today at> cd ~/my_source && ./make at> <CTRL-D> job 22 at 2006-10-14 17:00
Voila! The output will be collected by at and emailed to me.
What I actually typed in was:
at 10pm today<ENTER> cd ~/my_source && ./make<ENTER><CTRL-D>
If I screw up typing in the job command(s), I use atrm <JOB_ID> to remove it. atq lists jobs ids and scheduled date/time and at -c <JOB_ID> prints out the actual shell script that makes up a job.
batch(1) lets me run a job whenever system load permits. On my Fedora Core 5 desktop, the computer is usually just sitting idle so I never schedule jobs with batch(1).
According to the man page, Thomas Koenig wrote most of at. Thanks, Thomas!