It might well be more clear, but it doesn't work: 
#!/usr/bin/perl -w
                                                                      
+          
use Tk;
                                                                      
+          
use strict;
use warnings;
                                                                      
+          
my $mw = new MainWindow();

$mw->bind( '<KeyPress-Control-a>', sub {print "Button a has been press
+ed\n"} );
$mw->bind( '<KeyPress-Control-a>', sub {print "Button a has been relea
+sed\n"} );

MainLoop;

# Produces ...
bad event type or keysym "Control" at
/usr/lib/perl5/site_perl/5.8.0/i386-linux-thread-multi/Tk/Derived.pm l
+ine 469.

# My version of Perl
This is perl, v5.8.0 built for i386-linux-thread-multi

[download]
s''(q.S:$/9=(T1';s;(..)(..);$..=substr+crypt($1,$2),2,3;eg;print$..$/

In reply to Re^3: Tk: Binding Keys to events by liverpole
in thread Tk: Binding Keys to events by tamaguchi

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