ifa_ifwithaddr_psref
struct ifaddr *ifa_ifwithaddr_psref(const struct sockaddr *, struct psref *);
ifa = ifa_ifwithaddr_psref(ifaaddr, psref);
ifa = ifa_ifwithaddr_psref(info->rti_info[RTAX_IFA],
ifa = ifa_ifwithaddr_psref(info->rti_info[RTAX_IFA], psref);
ifa = ifa_ifwithaddr_psref(gateway, psref);