anchor.diff:      %% TODO: Do anything with PKey?
       try
           TaggedCSum = check_or_make_tagged_checksum(CSum_tag, Client_CSum,Chunk),
  -        FluName ! {seq_append, self(), Prefix, Chunk, TaggedCSum,
  -                   ChunkExtra, EpochID},
  +        R = {seq_append, self(), Prefix, Chunk, TaggedCSum, ChunkExtra, EpochID},
  +        FluName ! R,
           receive
               {assignment, Offset, File} ->
                   Size = iolist_size(Chunk),
  
positive.code:     case machi_flu_metadata_mgr:lookup_proxy_pid(FluName, {file, File}) of
          undefined ->
              ok;
          {ok, Pid} ->
            machi_file_proxy:sync(Pid, csum)
      end.
  
  
negative.code:     case sanitize_file_string(File) of
          ok ->
              {ok, Pid} = machi_flu_metadata_mgr:start_proxy_pid(FluName, {file, File}),
              case machi_file_proxy:read(Pid, Offset, Size) of
                  %% XXX FIXME 
                  %% For now we are omiting the checksum data because it blows up
                  %% protobufs.
                  {ok, Data, _Csum} -> {ok, Data};
                  Other -> Other
              end;
          _ ->
              {error, bad_arg}
      end.
  