#include <sys/ioctl.h>
#include <net/if.h>
#include <netinet/in.h>
#include <stdio.h>
#include <arpa/inet.h>

int main()
{
    char            buf[1024];
    struct ifconf   ifc;
    struct ifreq    *ifr;
    int             sck;
    int             count;
    int             i;

    sck = socket(PF_INET, SOCK_DGRAM, 0);
    if (sck < 0)
    {
        perror("socket");
        return 1;
    }

    ifc.ifc_len = sizeof(buf);
    ifc.ifc_buf = buf;
    if (ioctl(sck, SIOCGIFCONF, &ifc) < 0)
    {
        perror("ioerror");
        return 1;
    }

    ifr = ifc.ifc_req;
    count = ifc.ifc_len / sizeof(struct ifreq);

    for (i = 0; i < count; i++)
    {
        struct ifreq *item = &ifr[i];
        fprintf(stdout, "name: %s\n", item->ifr_ifrn.ifrn_name);
        fprintf(stdout, "hwaddr: %02x:%02x:%02x:%02x:%02x:%02x\n",
                        (unsigned char)item->ifr_hwaddr.sa_data[0],
                        (unsigned char)item->ifr_hwaddr.sa_data[1],
                        (unsigned char)item->ifr_hwaddr.sa_data[2],
                        (unsigned char)item->ifr_hwaddr.sa_data[3],
                        (unsigned char)item->ifr_hwaddr.sa_data[4],
                        (unsigned char)item->ifr_hwaddr.sa_data[5]);
    }
}