linux下獲得網卡的IP地址

#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <arpa/inet.h>
#include <errno.h>

void  getHostIp(char* netDev, char*ipaddress)
{
        int sock;
        struct sockaddr_in sin;
        struct ifreq ifr;

        sock = socket(AF_INET, SOCK_DGRAM, 0);
        if (sock == -1)
        {
                perror("socket");
                //return -1;
        }

        strncpy(ifr.ifr_name, netDev, IFNAMSIZ);
        ifr.ifr_name[IFNAMSIZ - 1] = 0;

        if (ioctl(sock, SIOCGIFADDR, &ifr) < 0)
        {
                perror("ioctl");
                //return -1;
        }

        memcpy(&sin, &ifr.ifr_addr, sizeof(sin));
        sprintf(ipaddress, "%s", inet_ntoa(sin.sin_addr));
        //return sin.sin_addr;
        //return 0;
}

void main()
{
        char ipaddress[16];
        getHostIp((char *)"eth0", ipaddress);
        printf("ip=%s\n", ipaddress);
}