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Functions

exit if another instance is running

Terminal - exit if another instance is running
pidof -x -o $$ ${0##*/} && exit
2009-11-20 12:58:41
User: frans
Functions: pidof
8
exit if another instance is running

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
if [ `fuser $0|wc -w` -gt "1" ];then exit; fi
2009-11-20 16:22:30
User: yooreck
Functions: wc
2

runs only one instance.

Know a better way?

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What others think

For a strong implementation of a real lock, see there : http://bash-hackers.org/wiki/doku.php?id=howto:mutex

Comment by sputnick 261 weeks and 4 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.

Comment by hackerb9 261 weeks and 3 days ago

Your point of view

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