errrrrrr

iodevice = file:open("client/" ++ Filename, [read, binary])

send_file_binary(Socket, IoDevice, Offset) ->
  case file:pread(IoDevice, Offset, 1000) of
    {ok, Data} ->
      io:format("~B bytes sent.", [Offset + 1000]),
      gen_tcp:send(Socket, <<1:32/integer, Data/binary>>),
      send_file_binary(Socket, IoDevice, Offset + 1000);
    eof ->
      io:format("File sent."),
      gen_tcp:send(Socket, <<2:32/integer>>) % 2 - uploading is done
  end.