I think I figured it out. Sometimes to processes open the file with the same filehandle, and they therefore share the lock because its tied to the filehandle.

So the questions become:
1) why do two processes have the same filehandle in some instances, but not in others?
2) how do i ensure that each process uses its own filehandle?

In reply to Re: flock LOCK_EX not locking exclusively by Anonymous Monk
in thread flock LOCK_EX not locking exclusively by Anonymous Monk

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