자신의 mac address를 저장하는 법 좀 가르쳐 주세요..

/* fpont 8/99 */

/*
* input IP address of a interface on the same network
* output MAC address of this interface if found if arp_cache
*
* OS tested linux 2.2.9
*/

#include
#include
#include
#include
#include
#include

int main(int argc, char *argv[])
{
struct sockaddr_in sin = { 0 };
struct arpreq myarp = { { 0 } };
int sockfd;
unsigned char *ptr;

if(argc!=2) {
printf("usage %s \n",argv[0]);
exit(0);
}

sin.sin_family = AF_INET;
if(inet_aton(argv[1], &sin.sin_addr)==0) {
printf("%s IP address '%s' not valid\n",argv[0],argv[1]);
exit(0);
}


memcpy(&myarp.arp_pa, &sin, sizeof myarp.arp_pa);
strcpy(myarp.arp_dev, "eth0");

if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
printf("%s cannot open socket\n",argv[0]);
exit(0);
}

if (ioctl(sockfd, SIOCGARP, &myarp) == -1) {
printf("%s no entry in arp_cache for '%s'\n",argv[0],argv[1]);
exit(0);
}

ptr = &myarp.arp_ha.sa_data[0];
printf("%s MAC address for '%s' is ",argv[0],argv[1]);
printf("%x%x%x%x%x%x\n",*ptr, *(ptr+1),*(ptr+2),
*(ptr+3),*(ptr+4),*(ptr+5));

return 1;
}

이걸 가지고 응용하시면 되겠죠?..