Perhaps you need to look at thread Tk tail -f - How?. I did post some code that I use for tailing inside a Tk app. Although my app runs on Unix, the code or something similar should work on any O/S that supports -s seek and tell.

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I'm Not Just Another Perl Hacker

In reply to Re: Tk - following a log file (tail -f) by rinceWind
in thread Tk - following a log file (tail -f) by spurperl

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