anchor.diff:  stream_multipart_ranged_body(Ranges, FileHandle, FileSize, Req0) ->
       Boundary = cow_multipart:boundary(),
       ContentType = cowboy_req:resp_header(?HDR_CONTENT_TYPE, Req0),
  -    
  +
       Req1 = http_streamer:init_stream(
           ?HTTP_206_PARTIAL_CONTENT,
           #{?HDR_CONTENT_TYPE => <<"multipart/byteranges; boundary=", Boundary/binary>>},
           Req0
       ),
  -    
  +
       StreamingCtx = http_streamer:build_ctx(FileHandle, FileSize),
       lists:foreach(fun(Range) ->
           NextPartHead = cow_multipart:first_part(Boundary, [
  
positive.code: 
  
  %% @private
  -spec stream_file_internal(undefined | [http_parser:bytes_range()], lfm:handle(), file_meta:size(), 
      cowboy_req:req()) -> {binary(), cowboy_req:req()}.
  stream_file_internal(undefined, FileHandle, FileSize, Req) ->
      stream_whole_file(FileHandle, FileSize, Req);
  
negative.code:         http_streamer:send_data_chunk(NextPartHead, Req1),
          http_streamer:stream_bytes_range(StreamingCtx, Range, Req1)
      end, Ranges),
  
      {Boundary, Req1}.
  
  
  