RTF_UP
if (!(r->flags & RTF_UP))
atrtr_default.flags = RTF_UP;
rtdef.rt_flags = RTF_UP;
flags |= RTF_UP;
rm.rt_flags = RTF_UP | RTF_GATEWAY;
.fc_flags = RTF_UP | flags,
.fc_flags = RTF_UP,
nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
RTF_UP | RTF_PREF(pref),
RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
.fc_flags = RTF_UP | RTF_NONEXTHOP,
.fc_flags = RTF_UP,