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Check if a process is running

Terminal - Check if a process is running
kill -0 [pid]
2009-05-19 11:37:20
User: sharfah
Functions: kill
5
Check if a process is running

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.

Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

Interesting. You can also have a look in /proc

[ -d /proc/1234 ] && command
Comment by flatcap 313 weeks and 5 days ago

If you don't know the pid, you can use pidof:

pidof firefox && command

Comment by Weboide 313 weeks and 4 days ago

Only if you own the process however. If you don't own the process it will fail even if the process is running.

Comment by romulusnr 290 weeks and 6 days ago

@romulusnr: but you still can find if that process exists by grep()ing for 'no such process' (or errno if C)

Comment by caruccio 161 weeks and 6 days ago

Your point of view

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