I've got two processes that both write to the same file using the same sequence: 
        open A,">>alldata.log" || die ("Cannot open file: $!");
        flock(A, LOCK_EX);
        seek(A, 0, SEEK_END) || die ("Cannot seek: $!");
        print A $logstring;
        close A

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Occasionally, I find that a long $logstring from one process will be interrupted by a $logstring from the other process and, at the new-line of the interrupting $logstring, the long $logstring will resume.

I thought that flushing was handled properly automatically.

PS: This happens with or without the seek.

In reply to flock seek flush by jabowery

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