From perlfaq5... 
seek(GWFILE, 0, 1);

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This clears the end-of-file condition on the handle, so that the next <GWFILE> makes Perl try again to read something.
If that doesn't work (it relies on features of your stdio implementation), then you need something more like this: 

        for (;;) {
          for ($curpos = tell(GWFILE); <GWFILE>; $curpos = tell(GWFILE
+)) {
            # search for some stuff and put it into files
          }
          # sleep for a while
          seek(GWFILE, $curpos, 0);  # seek to where we had been
        }

[download]
If this still doesn't work, look into the POSIX module. POSIX defines the clearerr() method, which can remove the end of file condition on a filehandle. The method: read until end of file, clearerr(), read some more. Lather, rinse, repeat.

There's also a File::Tail module from CPAN.

In reply to Re: tee -f? by Anonymous Monk
in thread tee -f? by Jonathan

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