As ikegami points out, the file open truncates the file before you have a chance to lock it.

A common solution is to use a different file for the cooperative locking. Make a file, "lockfile_logx" and get and release locks on that file's file handle to protect all of the operations on $file.

In reply to Re: Vexing Race Condition by Marshall
in thread Vexing Race Condition by Maelstrom

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