XtGetActionList
returns the action table defined by the specified widget class. This table
does not include actions defined by the superclasses. If widget_class is
not initialized, or is not coreWidgetClass or a subclass thereof, or
if the class does not define any actions, *actions_return will be NULL
and *num_actions_return will be zero. If *actions_return is non-NULL the
client is responsible for freeing the table using XtFree when it is no
longer needed.