Background

Say you run a qchem program. It may go on for some time. During this time it would be nice to be able to continue using your terminal - perhaps tracking the output of the program.

1. Pausing Ctrl-Z will pause your current process.
2. Backgrounding bg will cause your currently paused process will be restarted in the background.
3. The & The & symbol at the end of an input will automatically run the program in the background. E.g. qchem input output &
4. jobs This command shows all the processes running in the background. The id's are given for use with...
5. Foregrounding fg will cause one currently backgrounded process to be brought back the foreground - perhaps to be Ctrl-C killed.
6. top If you lose track of your processes running in the background, perhaps because your connection through ssh was reset, you can see all processes running on the computer with top. From here you can kill processes with 'k' + the PID listed. For more information see the top link under the introduction page.