#!/usr/bin/perl -w 
use strict;

use Tk;

my $mw = MainWindow->new();
my $text = 
    $mw->Text()->
    pack( -expand => 1, -fill => 'both' );

for my $x (0..255) {
    $text->insert( 'end', chr($x) );
}

MainLoop;
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I think you mean "available in the currently selected code page" not in the font. Yes, the ™(TM) symbol is present in the A[0-F] range in the Western code page. I chose that one because, since it is indeed in the 8-bit character set, it will be present in every (normal) font. That way, I didn't have to worry about which font the demo program was using, reducing the problem space.

A font will contain multiple encoding vectors, which map the character ordinal to a glyph (which has some internal ID). Latin-1, Latin-2, etc. may all be present in the same font file.

The characters I'm interested in, ultimatly, are not in that Latin-1 range. That was just a simple test.

I'm thinking the way to cope for now is to access the window handle and call SetWindowText directly, to draw the button faces. But my proof-of-concept is doing something funny...

—John