exit if another instance is running

pidof -x -o $$ ${0##*/} && exit

By: frans
2009-11-20 12:58:41

1 Alternatives + Submit Alt

What Others Think

For a strong implementation of a real lock, see there : http://bash-hackers.org/wiki/doku.php?id=howto:mutex
sputnick · 582 weeks and 6 days ago
I'm voting this one up, cause it's slick, not because it's a good idea. I learned long ago that the "one in a million" chance of a race condition being triggered (two processes checking pidof at the same time and not seeing each other) is actually a sure bet when you're on a machine that performs millions of ops per seconds.
hackerb9 · 582 weeks and 5 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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