test

#include <arpa/inet.h>

#include <net/if.h>

#include <sys/ioctl.h>

#include <sys/random.h>

#include <sys/socket.h>

#include <unistd.h>

void Ipv6Auto::dhcpStart(Iface &i, bool stateful, double now) {

    Dhcp6 &d = i.dhcp;

    if (d.state != Dhcp6::Off) dhcpStop(i, true);

    unsigned v[6];

    if (std::sscanf(readLine("/sys/class/net/" + i.name + "/address").c_str(), "%x:%x:%x:%x:%x:%x", &v[0], &v[1], &v[2],

                    &v[3], &v[4], &v[5]) == 6)

        for (int k = 0; k < 6; ++k) i.mac[k] = static_cast<uint8_t>(v[k]);

    int fd = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 0);

    // the MAC address (for the DUID) from the kernel: /sys/class/net shows

    // the interfaces of the namespace sysfs was mounted in, not the caller's

    ifreq ifr{};

    std::strncpy(ifr.ifr_name, i.name.c_str(), IFNAMSIZ - 1);

    if (fd >= 0 && ioctl(fd, SIOCGIFHWADDR, &ifr) == 0) std::memcpy(i.mac, ifr.ifr_hwaddr.sa_data, 6);

    int on = 1;

    sockaddr_in6 a{};

    a.sin6_family = AF_INET6;