修改MAC地址的方法（未测试）

用ioctl控制，通过SIOCGIFHWADDR获取MAC地址，SIOCSIFHWADDR设置MAC地址，不过在设置MAC地址之前，要先把网卡down掉，设置好了以后，再UP起来。

#include <sys/types.h> /* for socket(2) and related bits and pieces */
#include <sys/socket.h> /* for socket(2) */
#include <net/if.h> /* for struct ifreq */
#include <net/if_arp.h> /* for ARPHRD_ETHER */
#include <sys/ioctl.h> /* for IOCTL's */
#include <stdio.h> /* for fprintf etc */
#include <unistd.h> /* for close */

int main(int argc,char **argv)
{ struct ifreq ifr;
int skfd; if (argc<3)
{ fprintf(stderr,"usage:/n%s interface hwaddr/n",argv[1]); return 1; } /* Fill in the structure */ snprintf(ifr.ifr_name, IFNAMSIZ, "%s", argv[1]); ifr.ifr_hwaddr.sa_family = ARPHRD_ETHER; /* TODO: write some code to parse argv[2] into ifr.ifr_hwaddr.sa_data */ /* memcpy(&ifr.ifr_hwaddr.sa_data, argv[2], sizeof(ether.address)); */ /* Create a socket fd */ skfd = socket(PF_INET,SOCK_STREAM,0); /* call the IOCTL */ if (ioctl(skfd, SIOCSIFHWADDR, &ifr) < 0) { perror("ioctl(SIOCSIFHWADDR)"); return 1; }