FAQ 5.31 How do I do a "tail -f" in perl?

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5.31: How do I do a "tail -f" in perl?

    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.

    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

    If this still doesn't work, look into the "clearerr" method from
    "IO::Handle", which resets the error and end-of-file states on the

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


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