Complete PropertyChanged

void(* DOFObjectSubscribeCallback::PropertyChanged)(DOFObjectSubscribeCallback self, DOFOperation operation, DOFProviderInfo providerInfo, DOFValue value, DOFException except) Callback for a Requestor for the results of an asynchronous operation. This callback may be NULL to ignore notification of results. Parameters self The callback object. This will never be NULL. operation The original request operation. This will never be NULL. providerInfo The DOFProviderInfo associated with the value or except. This will never be NULL. value The current DOFValue of the property for the Subscribe Operation. Must be ignored if except is non-NULL. This may be NULL if the returned value is "NULL" (from a nullable type). except An exception received from a Provider. If NULL, no exception occurred (the Subscribe was successful) and value is valid.