Check if a process is running

kill -0 [pid]
Send signal 0 to the process. The return status ($?) can be used to determine if the process is running. 0 if it is, non-zero otherwise.

By: sharfah
2009-05-19 11:37:20

What Others Think

Interesting. You can also have a look in /proc [ -d /proc/1234 ] && command
flatcap · 684 weeks and 1 day ago
If you don't know the pid, you can use pidof: pidof firefox && command
Weboide · 684 weeks ago
Only if you own the process however. If you don't own the process it will fail even if the process is running.
romulusnr · 661 weeks and 1 day ago
@romulusnr: but you still can find if that process exists by grep()ing for 'no such process' (or errno if C)
caruccio · 532 weeks and 2 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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