anchor.diff:  %% Description: spawn laconica server interface process
   %%--------------------------------------------------------------------
   do_open_session(Url, PollFrequency) ->
  -    Site = #laconica_site{},
  +    laconica_site_model:write(#laconica_site{root_url = Url, poll_frequency = PollFrequency}),
       laconica_interface:start_link(Url).
   
   %%--------------------------------------------------------------------
  
positive.code: %% Description: spawn laconica server interface process
  %%--------------------------------------------------------------------
  do_public_timeline(Sessions) ->
      case length(Sessions) of
        0 -> webgnosus_events:warning(["open_session before retrieving public timeline."]), error;
        _ -> [gen_server:call(X, public_timeline)|| X <- Sessions]
      end.
        
  
negative.code: %% open session with specified Url
  handle_call({open_session, Url, PollFrequency}, _From, Sessions) ->  
      {Status, Pid} = do_open_session(Url, PollFrequency),
      case Status of
          ok -> {reply, Status, add_session(Url, Pid, Sessions)};
          _  -> {reply, Status, Sessions}
      end.
  
  %%--------------------------------------------------------------------
  %% open session with specified Url
  