anchor.diff:      true = register_server(TorrentID),
       Pending = etorrent_pending:await_server(TorrentID),
       InitState = #state{
  +        torrent_id=TorrentID,
           active=false,
           pending=Pending,
           assigned=gb_trees:empty(),
  
positive.code: -type chunkspec()   :: {pieceindex(), chunkoffset(), chunklength()}.
  
  -record(state, {
      active   :: boolean(),
      pending  :: pid(),
      assigned :: gb_tree(),
      fetched  :: gb_tree(),
      stored   :: gb_set()}).
  
  
  server_name(TorrentID) ->
  
negative.code:     {reply, IsActive, State};
  
  handle_call(activate, _, State) ->
      #state{active=false, torrent_id=TorrentID} = State,
      NewState = State#state{active=true},
      Peers = etorrent_peer_control:lookup_peers(TorrentID),
      [etorrent_download:activate_endgame(Peer) || Peer <- Peers],
      {reply, ok, NewState};
  
  handle_call({chunk, {request, _, Peerset, Pid}}, _, State) ->
  