#include <stdio.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>


int main( int argc, char *argv[] )
{
	int s;
		
	struct ifreq buffer;
	s = socket(PF_INET, SOCK_DGRAM, 0);
	memset(&buffer, 0x00, sizeof(buffer));
	strcpy(buffer.ifr_name, "eth0");
	ioctl(s, SIOCGIFHWADDR, &buffer);
	close(s);	
	for( s = 0; s < 6; s++ )
	{
		printf("%.2X ", (unsigned char)buffer.ifr_hwaddr.sa_data[s]);
	}
	printf("\n");

	return 0;
}

#include <stdio.h>

int main()
{
   
   FILE *cmd=popen("arp kcsdev | awk '{print $4}'", "r");
   char tmp[80]={0x0};
   
   while(fgets( tmp, sizeof(tmp), cmd)!=NULL)
   {
         printf("%s\n", tmp);
    }
   pclose(cmd);
   return 0;
}