This is another faq in just a few minutes. Well, sort of: in any case you may be interested in checking what perldoc -q tail has to tell you. To quote from it:

First try

    seek(GWFILE, 0, 1);

The statement "seek(GWFILE, 0, 1)" doesn't change the current position
+,
but it does clear the end-of-file condition on the handle, so that the
next <GWFILE> makes Perl try again to read something.
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