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Is it possible to launch a command or Bash script exit terminal and NOT interrupt command?
My solution was to run cron at a specific time of day, but I'm sure there is something easier.
Run Bash script in background and exit terminal
Answers
46
To avoid exit signals propagating to child processes of the terminal and shell, run the command with nohup, i.e.:
nohup cmd &
Thor
Posted 2012-07-13T12:03:01.327
Reputation: 5 178
For this to work, I had to change a preference in Terminal.app. Under Profiles, select your active profile, then Shell>When the shell exits>Close if the shell exited cleanly – antoine – 2017-05-09T01:12:17.970
1This is the correct answer. Without nohup, the started process is still considered a "child" of the terminal process and thus terminated if the terminal is closed. – Izzy – 2012-07-13T13:04:07.290
3cmd & disown works too, since the & is treated like a ; command separator. The disown command removes the connection between the bash shell session and the backgrounded command. – lornix – 2012-07-14T20:34:35.263
2zsh has a shorthand for this: cmd &|. – Thor – 2012-10-26T09:24:11.920
6
Using screen:
screen -S <session name> -d -m <your command>
after that you can quit the terminal, also you can reattach to it by:
screen -r <session name>
More info: reference
Bruce
Posted 2012-07-13T12:03:01.327
Reputation: 161
4
If you want to run a specific command or file every second or so in the background after exiting the terminal you could try this easy little thing;
nohup watch -n5 'bash script.sh' &
That would run scipt.sh every 5 seconds.
jamietelin
Posted 2012-07-13T12:03:01.327
Reputation: 149
1"nohup" is already covered by the accepted answer. And I'm pretty sure the asker mentioned cron because they were using it to say "Run this command a few seconds in the future", not to run it periodically. – David Richerby – 2015-08-06T21:01:29.547
1My answer don't make things worse. Do see the point of down vote. Neural would be sufficient. – jamietelin – 2015-08-06T21:41:30.777
3
Put a "&" character after your command.
e.g:
/home/your/script.sh &
Flinth
Posted 2012-07-13T12:03:01.327
Reputation: 342
This answer might work ok when combined with the jobs command. Quite often i want to be able to get back to the shell process after backgrounding it. – djangofan – 2018-12-07T19:17:21.090
Yeah, this answer was pretty limited. Actually, now I often use screen command for this. Type screen to open a new "session" run your things and close the terminal, the command will still be running in background. If you want to come back to this session just type screen -r – Flinth – 2018-12-08T23:27:54.257
7in this case, when the terminal is closed, so is the process started by /home/your/script.sh -- as it was not detached from its "parent", but just "backgrounded". Use nohup to detach it for real. – Izzy – 2012-07-13T13:05:51.050
My bad, I didn't knew about that, but when I tested on my Debian, the command kept executing after closing the shell which launched it :/ – Flinth – 2012-07-13T14:03:31.847
1
I'm not sure where exactly the backgrounded process is attached to and when. But if you e.g. log in to a remote machine, it is definitely stopped as soon as you log out (except if it daemonized itself). So to be 100% sure, you rather use nohup -- which also logs all (now invisible) output into a file called nohup.out located in the directory you started the command from.
Okay, well thank you for your explanations ^^ – Flinth – 2012-07-13T14:18:27.573
Duplicate: How do I detach a process from Terminal, entirely?
– slhck – 2012-07-13T12:19:10.097