being_smart_about_ownership_4.cpp

//Return a shared pointer, meaning this resource is shared
//Someone else might be using the underlying object
shared_ptr get_widget();

int use_widget() {
  auto widget_ptr = get_widget();
  //Thus we shall take the thread-safe approach and lock the widget before using it
  widget_ptr->lock_widget_mutex();
  if(widget_ptr->get_status() == 42)
    widget_ptr->trigger_event();
  widget_ptr->unlock_widget_mutex();
}