linux 使用 C 语言获得系统 MAC 地址

//google 到的  测试有效 
#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;
}