What you need is a THIRD file. You should never lock the file(s) you're processing, as this leads to all sorts of problems in most situations.

Lock the lock file
Check the files. If they've been copied already, do nothing. If not, copy them.
Unlock the lock file

Simple as that. The key is to eliminate simultaneous processing of files, and by separating the lock file from the files to be processed, you can achieve that easily.

In reply to Re: File Locking revisited by TedPride
in thread File Locking revisited by Jasper

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