linux下如何获取IP

int main()

{

struct ifreq stIfconfig;

char szIPeth0[16];

memset(szIPeth0,0x0,16);

int nNetWorkSocket = socket(AF_INET, SOCK_DGRAM, 0);

//获取eth0的ip

strncpy(stIfconfig.ifr_name, "eth0",5);

if (ioctl(nNetWorkSocket, SIOCGIFADDR, &stIfconfig) < 0)

{

printf( "ioctl does not get eth0!");

}

else

{

strncpy(szIPeth0,inet_ntoa(((struct sockaddr_in*)&(stIfconfig.ifr_addr))->sin_addr),IP_ADDR_LEN_MAX);

}

printf("IP = %s", szIPeth0);

return 0;

}