anchor.diff:  %%--------------------------------------------------------------------
   %%% Internal functions
   %%--------------------------------------------------------------------
  -contact_tracker(S) ->
  -    contact_tracker(S, none).
  -
   contact_tracker(S, Event) ->
       NewUrl = build_tracker_url(S, Event),
       case http:request(NewUrl) of
  
positive.code:       [S#state.url, S#state.info_hash, S#state.peer_id,
         Uploaded, Downloaded, Left, Port, E]).
  
  %%% Tracker response lookup functions
  find_next_request_time(BCoded) ->
      bcoding:search_dict_default(BCoded, "interval", ?DEFAULT_REQUEST_TIMEOUT).
  
negative.code: %% initialize.
  %%--------------------------------------------------------------------
  init([{ControlPid, StatePid, Url, InfoHash, PeerId}]) ->
      {ok, tracker_wait, #state{should_contact_tracker = false,
  			      control_pid = ControlPid,
  			      state_pid = StatePid,
  			      url = Url,
  			      info_hash = InfoHash,
  			      peer_id = PeerId}}.
  
  %%--------------------------------------------------------------------
  %% Function:
  