linux下获取网卡IP的C/C++代码

        简单：

#include <iostream>
#include <sys/types.h>
#include <sys/socket.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <malloc.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <linux/if.h>

#define BUF_SIZE 1024
using namespace std;

static int getIP(string net_name, string &strIP)
{
int sock_fd;
struct ifconf conf;
struct ifreq *ifr;
char buff[BUF_SIZE] = {0};
int num;
int i;

sock_fd = socket(PF_INET, SOCK_DGRAM, 0);
if ( sock_fd < 0 )
return -1;

conf.ifc_len = BUF_SIZE;
conf.ifc_buf = buff;

if ( ioctl(sock_fd, SIOCGIFCONF, &conf) < 0 )
{
close(sock_fd);
return -1;
}

num = conf.ifc_len / sizeof(struct ifreq);
ifr = conf.ifc_req;

for(i = 0; i < num; i++)
{
struct sockaddr_in *sin = (struct sockaddr_in *)(&ifr->ifr_addr);

if ( ioctl(sock_fd, SIOCGIFFLAGS, ifr) < 0 )
{
close(sock_fd);
return -1;
}

if ( (ifr->ifr_flags & IFF_UP) && strcmp(net_name.c_str(),ifr->ifr_name) == 0 )
{
strIP = inet_ntoa(sin->sin_addr);
close(sock_fd);

return 0;
}

ifr++;
}

close(sock_fd);

return -1;
}

int main()
{
string strIP;
getIP("eth1", strIP);
cout << strIP << endl;
return 0;
}
       测试OK