strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0) {
error("Couldn't mark interface down (get): %m");
strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0) {
error("Couldn't mark interface down (get): %m");