anchor.diff:  add_match(Bus, Match) ->
       gen_server:cast(Bus, {add_match, Match}).
   
  -export_service(Bus, Service, ServiceName) ->
  -    gen_server:call(Bus, {export_service, Service, ServiceName}).
  +export_service(Bus, ServiceName) ->
  +    gen_server:call(Bus, {export_service, ServiceName}).
  +
  +unexport_service(Bus, ServiceName) ->
  +    gen_server:call(Bus, {unexport_service, ServiceName}).
   
   %%
   %% gen_server callbacks
  
positive.code:     io:format("wait_ready received ~p~n", [Waiting]),
      {noreply, State#state{waiting=Waiting}};
  
  handle_call({export_service, Service, ServiceName}, _From, State) when is_pid(Service) ->
      BusObj = State#state.dbus_object,
  
      {ok, BusIface} = proxy:interface(BusObj, 'org.freedesktop.DBus'),
      {ok, _Header1} = proxy:call(BusIface, 'RequestName', [ServiceName, 0]),
      {reply, ok, State};
  
  handle_call(Request, _From, State) ->
  
negative.code: -export([get_object/3,
  	 wait_ready/1,
  	 add_match/2,
  	 export_service/2,
  	 unexport_service/2
  	]).
  
  %% gen_server callbacks
  