linux C 写MAC地址

// luo
//  gcc  mac.c
//  sudo ./a.out

// http://www.360doc.com/content/12/0406/08/1317564_201298802.shtml

// http://www.cnblogs.com/tzhangofseu/archive/2012/05/10/2493846.html

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/if.h>

#include <sys/types.h>
#include <stdlib.h>
#include <net/if_arp.h>

int  main()
{
    struct ifreq ifreq;
    int socket_id;
    int ret, i;
    char ifname[]="eth0";
    char mac_addr[18] = "08:00:27:88:88:88";
    char temp[6]= {0};

//==========================================
    printf("ifconfig  eth0  down \n");
    socket_id = socket(AF_INET,SOCK_STREAM,0);
    strncpy(ifreq.ifr_name, ifname, IFNAMSIZ);
    ifreq.ifr_flags &= ~IFF_UP;  // ifconfig   donw
    //ifreq.ifr_flags |= IFF_UP; // ifconfig   up
    ret = ioctl(socket_id, SIOCSIFFLAGS, &ifreq);
    close(socket_id);
    sleep(3);

//==========================================
    socket_id = socket(AF_INET,SOCK_STREAM,0);
    ifreq.ifr_addr.sa_family = ARPHRD_ETHER;
    strcpy(ifreq.ifr_name, ifname);

    sscanf(mac_addr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", \
    &temp[0], &temp[1], \
           &temp[2], &temp[3], \
           &temp[4], &temp[5] );

    for(i=0; i<6; i++)
    {
        //printf("%x:", temp[i]);
        ifreq.ifr_hwaddr.sa_data[i]= temp[i];
        printf("%x:", ifreq.ifr_hwaddr.sa_data[i]);
    }
//    memcpy((unsigned char *)ifreq.ifr_hwaddr.sa_data, temp, 6);


    ret = ioctl(socket_id, SIOCSIFHWADDR, &ifreq);
    if(ret < 0)
    {
        perror("error ioctl");
        return -1;
    }
    close(socket_id);

//==========================================
    printf("ifconfig  eth0  up \n");
    socket_id = socket(AF_INET,SOCK_STREAM,0);
    strncpy(ifreq.ifr_name, ifname, IFNAMSIZ);
    //ifreq.ifr_flags &= ~IFF_UP;  // ifconfig   donw
    ifreq.ifr_flags |= IFF_UP;     // ifconfig   up
    ret = ioctl(socket_id, SIOCSIFFLAGS, &ifreq);
    close(socket_id);

    return 0;
}