$ perldoc Tk::Widget
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$widget->Busy?(?-recurse => 1?-option = value>?)? This method configures a -cursor option for $widget and (if -recurse = 1> is specified) all its descendants. The cursor to be set may be passed as -cursor = cursor> or defaults to ’watch’. Additional configure options are applied to $widget only. It also adds a special tag ’Busy’ to the bindtags of the widgets so configured so that KeyPress, KeyRelease, ButtonPress and ButtonRelease events are ignored (with press events generating a call to bell). It then acquires a local grab for $widget. The state of the wid- gets and the grab is restored by a call to $widget->Unbusy.