What am I doing wrong?
You're not using warnings (use strict and warnings).

The problem also exists on linux. Here is what you would get with warnings: 

Name "main::FILE_HANDLE_1" used only once: possible typo at

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See also: What shortcuts can I use for linking to other information?:

File Locking

In reply to Re: Can't get flock() to work. Please help... by toolic
in thread Can't get flock() to work. Please help... by alain_desilets

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