> i was thinking that having a nul network interface might be useful
> for some purposes.

I think you're right.

> 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.

But would have different semantics.  Traffic that hits a reject route
generates an ICMP unreachable, as I recall; traffic routed out a nul
interface wouldn't.

> how many people think this is a silly idea?

I think it is very unsilly.  There's a decent chance I'll do it myself
soon (FSVO "soon").

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