思路：Linux中所有网卡名存放在/sys/class/net/目录下，虚拟网卡名存放在/sys/devices/virtual/net/目录下，故我们只需要获取所有网卡名后排除虚拟网卡名即可得到真实的网卡名。

ls /sys/class/net/ | grep -v "`ls /sys/devices/virtual/net/`"

 在Ubuntu中使用C语言实现结果如下：

#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <stdlib.h>
#include <sys/types.h>
#include <dirent.h>
#include <errno.h>
#include <iostream>
#include <vector>
using namespace std;
//获取文件目录下所有的文件名 
int scanFiles(vector<string> &fileList, string inputDirectory)
{
    inputDirectory = inputDirectory.append("/");

    DIR *p_dir;
    const char* str = inputDirectory.c_str();

    p_dir = opendir(str);   
    if( p_dir == NULL)
    {
    	printf("can't open: %s\n", inputDirectory.c_str()); 
    }

    struct dirent *p_dirent;

    while ( p_dirent = readdir(p_dir))
    {
        string tmpFileName = p_dirent->d_name;
        if( tmpFileName == "." || tmpFileName == "..")
        {
            continue;
        }
        else
        {
            fileList.push_back(tmpFileName);
        }
    }
    closedir(p_dir);
    return fileList.size();
}
//获取物理网卡的名字
char* get_real_name(char* real_name)
{
	//获取所有虚拟网卡mac名 
    vector<string> vMac;
    string path = "/sys/devices/virtual/net";
    int num = scanFiles(vMac, path);

    //获取所有网卡的信息 
    int sock, if_count, i;
    struct ifconf ifc;
    struct ifreq ifr[10];
    unsigned char mac[6];
    memset(&ifc, 0, sizeof(struct ifconf));

    sock = socket(AF_INET, SOCK_DGRAM, 0);

    ifc.ifc_len = 10 * sizeof(struct ifreq);
    ifc.ifc_buf = (char *)ifr;
    ioctl(sock, SIOCGIFCONF, (char *)&ifc);

    if_count = ifc.ifc_len / (sizeof(struct ifreq));
    //过滤出realMac 
    for (i = 0; i < if_count; i++) {        
        if (ioctl(sock, SIOCGIFHWADDR, &ifr[i]) == 0) {  
        	int label = 0;
        	for(int j = 0; j < num; j++){
				if(vMac[j].compare(string(ifr[i].ifr_name))  == 0){
					label = 1;	//有相等label=1 
				}
			}
			if(label == 0){
				real_name = ifr[i].ifr_name;
				memcpy(real_name, ifr[i].ifr_name, strlen(ifr[i].ifr_name));
				memcpy(mac, ifr[i].ifr_hwaddr.sa_data, 6);
				//printf("eth: %s, mac: %02x:%02x:%02x:%02x:%02x:%02x\n", ifr[i].ifr_name, mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
				break;	
			}         	
		} 
    }
	return real_name;
} 
//获取ip地址 
int get_local_ip(char * ifname, char * ip)
{
    char *temp = NULL;
    int inet_sock;
    struct ifreq ifr;

    inet_sock = socket(AF_INET, SOCK_DGRAM, 0); 

    memset(ifr.ifr_name, 0, sizeof(ifr.ifr_name));
    memcpy(ifr.ifr_name, ifname, strlen(ifname));
    //printf("get ip: %s\n", ifname);

    if(0 != ioctl(inet_sock, SIOCGIFADDR, &ifr)) 
    {   
        perror("ioctl error");
        return -1;
    }

    temp = inet_ntoa(((struct sockaddr_in*)&(ifr.ifr_addr))->sin_addr);     
    memcpy(ip, temp, strlen(temp));

    return 0;
}
//获取mac地址 
int get_mac(char * eth_name, char * mac_a)
{
    int                 sockfd;
    struct ifreq        ifr;

    sockfd = socket(AF_INET, SOCK_DGRAM, 0);
    if (sockfd == -1) {
        perror("socket error");
        return -1;
    }
	strcpy(ifr.ifr_name, eth_name);
	//printf("get mac: %s\n", eth_name);

    if (ioctl(sockfd, SIOCGIFHWADDR, &ifr) == 0) {  //SIOCGIFHWADDR 获取hardware address
        memcpy(mac_a, ifr.ifr_hwaddr.sa_data, 6);
    }
    
    return 0;
}

void run(char* ip, char* this_mac){
	//物理网卡名 
	char* real_macname = get_real_name(real_macname);
	printf("real macname: %s\n", real_macname);
	//mac
    get_mac(real_macname , this_mac);
    //printf("mac: %02x:%02x:%02x:%02x:%02x:%02x\n", this_mac[0]&0xff, this_mac[1]&0xff, this_mac[2]&0xff, this_mac[3]&0xff, this_mac[4]&0xff, this_mac[5]&0xff);
	
    //ip
    get_local_ip(real_macname, ip);
}

int main(void)
{	

	char ip[32] = {0};
	char mac[6] = {0};
	run(ip, mac);
	
	printf("ip: %s\n", ip);
	printf("mac: %02x:%02x:%02x:%02x:%02x:%02x\n", mac[0]&0xff, mac[1]&0xff, mac[2]&0xff, mac[3]&0xff, mac[4]&0xff, mac[5]&0xff);
	
	
    return 0;
}

编译运行：

g++ -o t1 GetIpMac.cpp  #该程序文件名为GetIpMac.cpp
./t1

运行结果如下：