"If you want your routine to be called with every keystroke, then bind every keystroke."

That was my first thought too, but that does not seem to work either.

use warnings;
use strict;

use Tk;

my $MW = MainWindow->new(-title => "Tk::Text test",
                         -width => 200,
                         -height => 200);

my $text = $MW->Text(-height => 10,
                     -width  => 40,
                     -wrap   => 'word');
$text->pack(-side => 'top', -fill => 'both');
$text->bind('<<Modified>>' =>
            sub { getText($text, @_) } );

MainLoop;

sub getText
{
    my ($t, @args) = @_;

    my $str = $t->get('0.0', 'end');

    print "Got: $str\n";
$text->bind('<<Modified>>' =>
            sub { getText($str, @_) } );
    return if(!$str);

    return 1;
}
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