Resume Process via PID

If you run a lot of daemons or other background processes, it’s easy to lose track of them from time to time. For instance the other day I shut down my terminal session while mongod was running, and when I returned to it, I had no idea how to get it back.

Fortunately, the process is simple:

1. Find the process ID — ps ax or aux and you can even grep on this like ps ax | grep mongo.
2. Use the kill command and send a SIGCONT signal, which indicates that the process should resume, so — kill -CONT 123456, at least in my shell.

On a related note, kill is one of those commands which can differ between systems a bit, so you might want to check out man kill and man builtin.

You can also learn more about kill and signal commands here.