Your file locking appears to be fine. I can't be sure, because I don't know that LOCK_EX == 2 on your system. It would be good to add use Fcntl qw(:flock); to the top and use your constants by name. I'd also encourage you to use a lexical file handle instead of localizing *FH. A lexical handle is closed when its name goes out of scope and no other references exist.

Several question that may point to the problem: Are you sure no other script is accessing the counter? Does your OS support flock in all its glory? Is this the actual code, or is it trimmed for the question?

That is some commendably clean code.

After Compline,
Zaxo

In reply to Re: Concurrent file access with flock() by Zaxo
in thread Concurrent file access with flock() by Anonymous Monk

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