anchor.diff:  %% Description: Shutdown the server
   %% Returns: any (ignored by gen_server)
   %%--------------------------------------------------------------------
  -terminate(Reason, State) ->
  +terminate(Reason, _State) ->
       case Reason of
   	normal -> true;
   	_ -> logger:log(error, "Registrar terminating : ~p", [Reason])
  
positive.code: %% Purpose: Convert process state when code is changed
  %% Returns: {ok, NewState}
  %%--------------------------------------------------------------------
  code_change(OldVsn, State, Extra) ->
      {ok, State}.
  
  %%--------------------------------------------------------------------
  
negative.code: %%          {stop, Reason, Reply, State}   | (terminate/2 is called)
  %%          {stop, Reason, State}            (terminate/2 is called)
  %%--------------------------------------------------------------------
  handle_call(Request, _From, State) ->
      logger:log(error, "Registrar: Received unknown gen_server call : ~p", [Request]),
      {reply, {error, "Unknown gen_server call", State}}.
  
  