Sorry for the noise, but I forgot a case; it's sometimes difficult to
describe code paths by hand...

Pierre Pronchery wrote:
> From src/usr.sbin/arp/arp.c (NetBSD 3.0.1_PATCH):
> 
> 301 overwrite:
> 302         if (sdl->sdl_family != AF_LINK) {
> 303                 warnx("cannot intuit interface index and type for %s",
> 304                     host);
> 305                 return (1);
> 
> which is reached if:
> 
> 286         if (sina->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
> 287                 if (is_llinfo(sdl, rtm->rtm_flags))
> 288                         goto overwrite;

or if (sina->sin_addr.s_addr != sin_m.sin_addr.s_addr) of course.

Cheers,
-- 
khorben