MFC 외부IP, 내부IP 알아내기

#define DESIRED_WINSOCK_VERSION        0x0101
#define MINIMUM_WINSOCK_VERSION        0x0001

// 내부 IP 가져오기CString GetInIpAddress()
{
    WSADATA wsadata;
    CString strIP = _T("");

    if (!WSAStartup(DESIRED_WINSOCK_VERSION, &wsadata))
    {
        if (wsadata.wVersion >= MINIMUM_WINSOCK_VERSION)
        {
            HOSTENT *pHostInfo;
            IN_ADDR in;
            char hostName[128] = { 0,};

            gethostname(hostName, 128);
            pHostInfo = gethostbyname(hostName);

            if (pHostInfo != NULL)
            {
                int i = 0;
                for (; pHostInfo->h_addr_list[i]; i++) {}
                memcpy(&in, pHostInfo->h_addr_list[--i],4);
                strIP = inet_ntoa(in);
            }
        }
        WSACleanup();
    }
    return strIP;
}

// 외부 IP 가져오기CString GetIpAddress()
{
    WORD wVersionRequested = MAKEWORD(2,0);
    WSADATA wsadata;
    char hostName[128] = { 0,};
    PHOSTENT hostInfo;
    CString strIP = _T("");

    if (WSAStartup(wVersionRequested, &wsadata) == 0)
    {
        if (gethostname(hostName, sizeof(hostName)) == 0)
        {
            if((hostInfo = gethostbyname(hostName)) != NULL)
                strIP = inet_ntoa(*(in_addr *)*hostInfo->h_addr_list);
        }
        WSACleanup();
    }
    return strIP;
}