In the TIMTHOWTDI spirit, you could configure your FTP server to allow only 1 simultanous login for username in question. This will work as a very simple locking mechanism, where only one user will be able to access file on the FTP. One of the users will be your vendor, and another - your perl script.

Leonid Mamtchenkov aka TVSET

In reply to Re: Detecting An Open File by TVSET
in thread Detecting An Open File by gnu@perl

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