2013/2/24 ko1 (Koichi Sasada) <redmine / ruby-lang.org>:

> Feature #7476: missing "IP_TRANSPARENT" constant for IP sockets.
> https://bugs.ruby-lang.org/issues/7476#change-36913

> There is a missing constant for IP_TRANSPARENT on linux.
> to set the TPROXY on a socket I use:
> s.setsockopt(Socket::SOL_IP, 19, 1)
> The 19 suppose to be as a constant named: IP_TRANSPARENT or Socket::IP_TRANSPARENT.

This is Linux-specific and only defined in linux headers
such as /usr/include/linux/in.h.

I'm not sure applications can safely use such headers.
-- 
Tanaka Akira