#!/usr/bin/perl

use strict;
use warnings;

use Tk;
use IO::File;

my $mw = MainWindow->new();
my $st = $mw->Scrolled( 'Text', -scrollbars => 'eo' )->pack();
$st->repeat( 3000, \&list );
MainLoop;

sub list {
    my $fh = IO::File->new();
    open $fh, q{<}, '/usr/lib/perl5/site_perl/5.8.8/i386-linux-thread-
+multi/Tk/Text.pm';

    while (<$fh>) {
        $st->insert( 'end', "line $_\n" );
        return;
        
    }
}   
1;
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Update: Fixed. It should work now. Sorry for the delay. The main reason that I did it this way is that I used Perl::Critic, and it recommended IO::File. Also, it recommended a 3-arg open, which seems to work a little better. There's an online Perl::Critic at http://perlcritic.com/