anchor.diff:      {ok, Client, {send, self, "ok"}};
   
   handle(#s_client{} = Client, _Command, _Args) ->
  -    {ok, Client, none}.
  +    {ok, Client, {send, self, ?R_UNKNOWN}}.
  
positive.code: 
  handle(#s_client{} = Client, ?C_AUTH_LOGIN, [Id]) ->
      case db_auth:login(#t_session{id = Id}) of
          none -> {ok, Client, {send, self, ?ERROR}};
          {session, Session} ->
              {
                  ok, Client#s_client{identity = Session#t_session.user_id},
  
negative.code:                 {send, self, uuid:uuid_to_string(Session#t_session.id)}
              };
          false ->
              {ok, Client, {send, self, ?R_ERROR}}
      end;
  
  handle(#s_client{} = Client, ?C_AUTH_LOGOUT, [Id]) ->
  