C++在windows下獲取本地主機ipv4地址和ipv6地址

#include <Winsock2.h>

include <stdio.h>
include <iostream>
include <cstring>
include<ws2tcpip.h>
pragma comment(lib, "ws2_32.lib ")  //linking to the library
using namespace std;
int get_ip()
{
    struct addrinfo ailist, aip;

    struct addrinfo hint;

    struct sockaddr_in6 sinp6; 
    PHOSTENT hostinfo;
    char hostname[255] = {0};      //主機名

    char port = "3294";                              //端口號
    const char addr;

    int ilRc;
    gethostname(hostname, sizeof(hostname));
    if((hostinfo = gethostbyname(hostname)) == NULL)    //獲得本地ipv4地址
    {
        errno = GetLastError();
        fprintf(stderr,"gethostbyname Error:%d\n", errno);
        return 1;
    }
    LPCSTR ip;
    while((hostinfo->h_addr_list) != NULL)        //輸出ipv4地址
    {
        ip = inet_ntoa((struct in_addr ) hostinfo->h_addr_list);
        printf("ipv4 addr = %s\n\n", ip);
        hostinfo->h_addr_list++;
    }
    hint.ai_family = AF_INET6;                   /  hint 的限定設置  /
    hint.ai_socktype = SOCK_STREAM;     /   這里可是設置 socket type    比如  SOCK——DGRAM /
    hint.ai_flags = AI_PASSIVE;                    // flags 的標志很多  。常用的有AI_CANONNAME;
    hint.ai_protocol = 0;                               /  設置協議  一般為0，默認 /

    hint.ai_addrlen = 0;                                /  下面不可以設置，為0，或者為NULL  /
    hint.ai_canonname = NULL;

    hint.ai_addr = NULL;

    hint.ai_next = NULL;
    ilRc = getaddrinfo(hostname, port, &hint, &ailist);    /通過主機名獲得地址信息/

    if (ilRc < 0)

    {

        char str_error[100];

        strcpy(str_error, (char )gai_strerror(errno));

        printf("str_error = %s", str_error);

        return 0;

    }
    if(ailist == NULL)
    {
        printf("sorry not find the IP address,please try again \n");
    }
    for (aip = ailist; aip != NULL; aip = aip->ai_next)                         / 顯示獲取的信息  /
    {

        aip->ai_family == AF_INET6;
        sinp6 = (struct sockaddr_in6 )aip->ai_addr;                                  / 為什么是for 循環 ，先向下看 */
        int i;
        printf("ipv6 addr = ");
        for(i = 0; i < 16; i++)
        {
            if(((i-1)%2) && (i>0))
            {
                printf(":");
            }
            printf("%02x",sinp6->sin6_addr.u.Byte[i]);

        }
        printf(" \n");
        printf(" \n"); 
    }
    while(1);

}
int main(){

WORD wVersionRequested;
WSADATA wsaData;
int err;   
wVersionRequested = MAKEWORD( 1, 1 );
err = WSAStartup( wVersionRequested, &wsaData );//initiate the ws2_32.dll and match the version
if ( err != 0 )
{
    return 0;
}
if ( LOBYTE( wsaData.wVersion ) != 1 ||   //if the version is not matched ,then quit and terminate the ws3_32.dll
    HIBYTE( wsaData.wVersion ) != 1 )
{
    WSACleanup( );
    return 0;
}
get_ip();
return 0;

}</pre>