Well then, just use the tie mode of File::Tail:

if ($opt{'c'}) {
    open ( CATLOG, '<', $MAILLOG )
         or die "Can't open $MAILLOG: $!\n";
} else {
    my $ref = tie *CATLOG, "File::Tail",(
        name  => $MAILLOG,
        tail  => -1
    ) or die "Can't tie $MAILLOG: $!\n";
}
while (my $line = <CATLOG>) {
    # ...while loop code here...
}
[download]

One more thing: Always check the return value of open / close.

cheers,
--shmem

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}