Symbol: PRC_IFDOWN
sys/net/if.c
1756
kpfctlinput(PRC_IFDOWN, ifa->ifa_addr);
sys/netinet/ip_carp.c
3194
if (cmd != PRC_IFDOWN && cmd != PRC_IFUP)
sys/netinet/ip_carp.c
3205
if (cmd == PRC_IFDOWN) {