FAQ 5.33 How do I do a "tail -f" in perl?

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5.33: 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
handle.

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



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