plan 9 IP routing

gistfile1.diff

minooka; diff -c /n/dump/2010/0930/sys/src/9/ip/ip.c /n/dump/2010/0820/sys/src/9/ip/ip.c
/n/dump/2010/0930/sys/src/9/ip/ip.c:463,469 - /n/dump/2010/0820/sys/src/9/ip/ip.c:463,469
               }

               /* don't forward to source's network */
-               memset(&conv, 0, sizeof conv);
+               conv.r = nil;
               r = v4lookup(f, h->dst, &conv);
               if(r == nil || r->ifc == ifc){
                       ip->stats[OutDiscards]++;