For this code 

    until (flock FH, LOCK_EX) {
        sleep 1;
        die "Can't get exclusive lock $!\n" if $tries++ > $timeout
    }

[download]
either change LOCK_EX to LOCK_EX|LOCK_NB or just drop the whole loop counting retries because flock(FH,LOCK_EX) simply waits until the lock is obtained.

Also, the seek isn't needed on any platform I know of. Windows needs the locking but already seeks each time you write to a file in append mode (though it certainly won't hurt). And I'd be sure to turn on "autoflush" for the file handle since you are using print to write the data.

        - tye (but my friends call me "Tye")

In reply to (tye)Re2: (OT?) File Locking by tye
in thread (OT?) File Locking by Anonymous Monk

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