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# 1  
Old 03-12-2009
Question sleep 10 && command doesn't work

Hi there,
I found a trick to easily postpone a command by a few seconds:
supernova:~# sleep 10 && command &

If you logout, the command should still be executed... But not all the time.
Could anyone of you explain me why the following command is executed even after logging out:
supernova:~# sleep 10 && touch somefile &

and not that one:
supernova:~# sleep 10 && /etc/init.d/networking force-reload &

Thanks in advance
# 2  
Old 04-15-2009
When you log out of a terminal, a HUP signal is sent to the shell, which passes that signal on to all the tasks/jobs you have running in that terminal. The && means "run the second command if the first command succeeded", and exiting with a signal usually means the command did [i]not[i] succeed, so the second command should not run. So the question really is, why does the first command work? That I am unsure about it. It could be a matter of timing -- you log out just as the sleep command exits.

If you are using BASH, there are several caveats to all this.

If you want to make sure something finishes even after you log off, you can do:
nohup sh -c "sleep 10; /etc/init.d/networking force-reload" &

# 3  
Old 04-21-2009
You're right otheus,
Actualy, when I run my touch command, if I logout immediatly (using ctrl+D) the windows freezes for 10 seconds before it actually closes. So obviously, it waits until the command complete and thus explains why the command indeed works.
Thanks for your idea!

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