通过ioctl 获得网卡的HW/IP address

int get_mac_ip (const char *ifc, unsigned char mac[6],unsigned char ip[15])

{

register int fd;

struct ifreq ifr;

unsigned char *p = NULL;

int i;

int err = 0;

if ((fd = socket (AF_INET, SOCK_DGRAM, 0)) >= 0) 

{

memset(&ifr, 0, sizeof(struct ifreq));

sprintf(ifr.ifr_name, "%s", ifc);

if((ioctl (fd, SIOCGIFADDR, &ifr))>=0)

{

strcpy( ip, (char*)inet_ntoa(((struct sockaddr_in*)(&ifr.ifr_addr))->sin_addr));

}

else

{

err = 1;

}

if((ioctl (fd, SIOCGIFHWADDR, &ifr))>=0)

{

p = ifr.ifr_hwaddr.sa_data;

for(i=0;i<6;i++)

mac[i] = p[i];

}

else

{

err = 2;

}

} 

close(fd);

return err;

}