anchor.diff:           <<Chunk:Len/binary, Rest/binary>> = Buffer,
            {emit,
               [{http, Uri, Chunk}, {http, Uri, eof}],
  -            'IO',
  +            'ACTIVE',
               S#fsm{
                  buffer = Rest
               }
  
positive.code: %%% ACTIVE
  %%%
  %%%------------------------------------------------------------------   
  'ACTIVE'({Prot, _Peer, terminated}, #fsm{prot=P}=S)
   when Prot =:= P ->
     {stop, normal, S};
  
negative.code:          thttp = counter:add(idle, Thttp),
           trecv = counter:add(now,  Trecv)
        }, 
        0 % sometimes timeout is arrived later then data packet
     }.
  
  %%%------------------------------------------------------------------
  