Running python code in background

Question

I need to run a python code that takes several hours and my computer disconnects from the ssh after a certain amount of inactive time.

I have tried python test.py> output.txt & but my output file is empty. However, the python code "test" is still running after I log off and log back in to the ssh. I also tried python -u test.py> output.txt & which does write to the output.txt but it does not continue after the ssh connection is lost.

I am very new to Linux so I do not know very many commands. I need the simplest/easiest to understand method. Thanks!

Answer 1

You can use screen, as Robin Krahl recommended, or you can just run your command with nohup, which suppresses the SIGHUP (hangup) signal from your SSH session disconnecting.

nohup "python -u test.py > output.txt" &

Answer 2

screen is the tool you want to use.

Answer 3

As others have said, screen is what you want. tmux is newer? tool that does the same thing, and byobu is an easy-to-use wrapper for both.