stream_rar.c peeks the first few bytes when trying to open, which means
that opening any stream reads at least 2KB of data (internal buffer
size) on opening. This broke --stream-dump, which saved only the data
following this initial buffer.
Hack it around by writing the current buffer to the capture file too,
and move stream_capture_write() above stream_set_capture_file() for this
purpose.
Cleaner solutions might include: handling the terrible rar thing
differently, or using the "proper" stream API for dumping. (The latter
is not done, because --stream-dump shares code with the --stream-capture
misfeature.)
Fixes#1215.
wm4
aaa29eb81e