Keeping programs/scripts running after logoff
Leading up to getting our scripts to run as daemons, we need to know how to keep commands running after a user logs off (or better yet, have them started by the system itself (we will look at this in more detail later). When a user logs in, a session for that user is created, but when they log off—unless the system owns it, processes and scripts typically get killed or closed.
This recipe is about keeping your scripts and activities running in the background after you log off.
Getting ready
Besides having a terminal open, we need to remember a few concepts:
- When a user logs off, any apps or processes owned by the current user will exit (the shell will send a signal)
- The shell is configurable to not send a shutdown signal to processes
- Applications and scripts use stdin and stdout for the usual operations
- Applications or scripts in the background can be referred to as jobs
The purpose of this chapter is to not show you process management, but how we can...