anchor.diff:      { reply, [ invalid_command ], St}.
   
   
  +		      
   handle_cast({rvi, service_available, [SvcName, _DataLinkModule] }, St) ->
       announce_service_availability(available, SvcName),
       { noreply, St };
  
positive.code: 	      unavailable -> services_unavailable
  	  end,
  
      ets:foldl(
        %% Notify if this is not the originating service.
        fun(#service_entry { 
  	     service = ServiceEntry,
  	     url = URL }, _Acc) when 
  		ServiceEntry =/= SvcName ->
  
  	      dispatch_to_local_service(URL, Cmd, 
  					{struct, [ { services, 
  						     { array, [SvcName]}
  						   }
  						 ]}),
  	      [];
  
  	 %% This is the originating service regsitering itself. Ignore.
  	 (_, _) -> []
  
        end, [], ?SERVICE_TABLE).
  
negative.code: 
  %% Dispatch to regular JSON-RPC over HTTP.
  dispatch_to_local_service(URL, Command, Args) ->
      CmdStr = atom_to_list(Command),
      ?debug("dispatch_to_local_service():  Command:         ~p",[ CmdStr]),
      ?debug("dispatch_to_local_service():  Args:            ~p",[ Args]),
      ?debug("dispatch_to_local_service():  URL:             ~p",[ URL]),
      Res = rvi_common:send_json_request(URL, CmdStr, Args),
      ?debug("dispatch_to_local_service():  Result:          ~p",[ Res]),
      Res.
  