If you are the one doing the "printing" and that's what it sounds like: 
# make a frame, say frame_text, then create a text
# widget:

my $text = $frame_text->Scrolled ('Text', -scrollbars=>'se', )
                             ->pack(-expand=>1, -fill=>'both');
#append lines with:
$text->insert ('end', $_);

#delete all lines
$text->delete("1.0", 'end');

[download]
Multi-threads and re-directing output from other program is more complex, but if all you need is that your "command line output" gets put into the GUI, just follow the above.

In reply to Re: Displaying print statements in Tk by Marshall
in thread Displaying print statements in Tk by senthilkumar

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