in reply to How to do atomic file locking?

The trick is to ignore the open call in your sequence of locking. Two or more processes can (on Unixish operating systems) successfully call open() on the same file, but only one call to flock() will succeed. That should be enough for your program to know whether it is the instance that should proceed or not.

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Re^2: How to do atomic file locking?
by Acapulco (Novice) on Aug 25, 2015 at 20:44 UTC

    Thanks! I was not aware of this.

    So now my question is, if two files get to open the file (I'm working on Linux 2.6 kernel so I guess this can happen) but only one gets the lock.

    Which call will fail? The flock one? can I do "flock or die"?

    Again, thanks a lot. I couldn't find any references to this behavior.

[reply]

      Nevermind. It seems that indeed I can do flock or die.

[reply]

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