anchor.diff:     response,% active response
   
      iolen,   % expected length of data
  +   pckt,    % number of processed payload chunks
   
      opts,    % http protocol options
      buffer   % I/O buffer
  
positive.code:    'REQUESTED'/2,  %% server is requested
     'RESPONSE'/2,   %% server is responding
     'STREAM'/2,     %% payload is streamed (chunked)
     'CHUNK'/2,      %% receive chunk
     'RECV'/2        %% payload is received
  ]). 
  
  