[kees99]

Option "-l" only supposed to be used with text output. When mis-applied to binary (-w) output, it will:

- On Linux, flush buffer at wrong places, breaking last (few) packet(s);

- On Windows, flush buffer after every byte (which gives acceptable result, but is very inefficient).

With "-w", always use "-U" instead.

[iammeow]

Thank you so much, not had a clue

[unixhero]

Who would have known that :) I sense a project developer is contributing to the discussion here :).