$mw->bind('<ButtonPress-1>',    sub{ 
        my $xe = $mw->XEvent;
        $wdragiinfo{xoff} = $mw->pointerx - $mw->rootx;
        $wdragiinfo{yoff} = $mw->pointery - $mw->rooty;
        });
        
        $mw->bind('<B1-Motion>',    sub{ 
        my ($x,$y);
        $x=$mw->pointerx-$wdragiinfo{xoff};
        $y=$mw->pointery-$wdragiinfo{yoff};
        
        $mw->geometry($mw->width."x".$mw->height."+$x+$y");
         });
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