use strict;
use Tk;
use Win32::MMF::Shareable;

my $wait;
tie( $wait, 'Win32::MMF::Shareable', 'wait' );
$wait = 0;

my $pid;
unless( $pid = fork )
{
  $SIG{HUP} = \&stop;
  while( 1 ) { sleep 1 }
}

my $mw = MainWindow->new;
$mw->Button( -text => '$wait',                   -command => sub { pri
+nt "\$wait is $wait\n" } )->pack;
$mw->Button( -text => 'waitVariable( \\$wait )', -command => \&start )
+->pack;
$mw->Button( -text => 'local $wait++',           -command => \&stop  )
+->pack;
$mw->Button( -text => 'remote $wait++',          -command => sub{ kill
+( 'HUP', $pid ) } )->pack;

MainLoop;

kill( 'TERM', $pid );

sub start
{
  print "waiting for \$wait (was $wait)\n";
  $mw->waitVariable( \$wait );
  print "finished waiting for \$wait (is now $wait)\n";
}

sub stop
{
  print "\$wait++ by pid $$\n";
  $wait++;
}

__END__

# [\d] is button pressed

$wait is 0                             # [1] start on 0
waiting for $wait (was 0)              # [2] start waiting
$wait++ by pid 2372                    # [3] increment locally
finished waiting for $wait (is now 1)  # ... all okay
waiting for $wait (was 1)              # [2] wait again
$wait++ by pid -2184                   # [4] increment remotely
                                        # ... nothing happens
$wait is 2                             # [1] but it has been increment
+ed
$wait++ by pid 2372                    # [3] increment locally again
finished waiting for $wait (is now 3)  # ... and it works
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use japh; print;
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