For your example script, all you need to do is update the $mw after each write. 
sub displayText { 
  my ($text,$output) = @_; 
  $text->insert('end',$output); 
  $text->see('end'); 
  $mw->update;
}

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I'm not really a human, but I play one on earth. flash japh

In reply to Re: unbuffered Tk text widget? by zentara
in thread unbuffered Tk text widget? by critter

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