linux 获取本地mac地址(指定网卡)

// 获取本地mac
std::string getLocalMac()
{
#ifndef _WIN32
	int sock_mac;
	struct ifreq ifr_mac;
	char mac_addr[30];
	sock_mac = socket(AF_INET, SOCK_STREAM, 0);
	if (sock_mac == -1)
	{
		perror("create socket falise...mac\n");
		return "";
	}

	memset(&ifr_mac, 0, sizeof(ifr_mac));
	strncpy(ifr_mac.ifr_name, "eth0", sizeof(ifr_mac.ifr_name) - 1);

	if ((ioctl(sock_mac, SIOCGIFHWADDR, &ifr_mac)) < 0)
	{
		printf("mac ioctl error\n");
		close(sock_mac);
		return "";
	}

	sprintf(mac_addr, "%02X:%02X:%02X:%02X:%02X:%02X",
		(unsigned char)ifr_mac.ifr_hwaddr.sa_data[0],
		(unsigned char)ifr_mac.ifr_hwaddr.sa_data[1],
		(unsigned char)ifr_mac.ifr_hwaddr.sa_data[2],
		(unsigned char)ifr_mac.ifr_hwaddr.sa_data[3],
		(unsigned char)ifr_mac.ifr_hwaddr.sa_data[4],
		(unsigned char)ifr_mac.ifr_hwaddr.sa_data[5]
	);

	close(sock_mac);

	return mac_addr;
#else
	return "00:00:00:00:00:00";
#endif
}