i was thinking that having a nul network interface might be useful for
some purposes.  at the very least, all the reject routes that get
installed could be changed to dump traffic out a nul interface
instead, which might make visual inspection of the routing table easier.

i made one a while back, and while i don't have the code any more, i
seem to recall it being not much more than a pseudo-device (just like
lo), and a copy of net/if_loop.c with the names all changed to
nulfoo()) instead of lofoo().  the one difference was the nuloutput()
routine which turned into something like this:

	/* ARGSUSED */
	int
	nuloutput(ifp, m, dst, rt)
		struct ifnet *ifp;
		struct mbuf *m;
		struct sockaddr *dst;
		struct rtentry *rt;
	{

		m_freem(m);

		return (0);
	}

so that all traffic that went that way would just disappear.

how many people think this is a silly idea?

-- 
|-----< "CODE WARRIOR" >-----|
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