Problem when Creating AsyncSocket

I have two network cards on my machine and I retrieve their info by the following code, mainly their IP addresses:

Code:

---

hostent *host = NULL;
char hostName[128] = "";
sockaddr_in sockAddr;
char m_UIWIp[2][16];
CString tempIP;

gethostname(hostName, sizeof(hostName));

host = gethostbyname(hostName);

if (!host)
{
        AfxMessageBox("Error getting local IP address", MB_OK);
}
else
{
        //set IPs for both network cards
        for (int i = 0; host->h_addr_list[i]; i++)
        {
                memcpy(&sockAddr.sin_addr, host->h_addr_list[i], host->h_length);
                tempIP =  inet_ntoa(sockAddr.sin_addr);

                <snip>

                m_UIWIp[0] = tempIP
        }
}

---

Later I user this address in setting up some sockets:

Code:

---

for (i = 0; i < 2; i++)
{
        if (!m_WrTCMSockFd[i].Create(WRITE_PORT,SOCK_DGRAM , FD_WRITE, m_UIWIp[i]))
        {
                nLastError = m_WrTCMSockFd[i].GetLastError();        // Obtain the error code
                switch (nLastError)
                {
                        case WSAEAFNOSUPPORT:
                                MidOutMsg,"Address family is not supported\n";
                                break;
                        case WSAEMFILE:
                                MidOutMsg="No more file descriptors available\n";
                                break;
                        case WSAENOBUFS:
                                MidOutMsg="No buffer space is available\n";
                                break;
                        case WSAEPROTONOSUPPORT:
                                MidOutMsg="Specified port not supported\n";
                                break;
                        case WSAEPROTOTYPE:
                                MidOutMsg="Specified port is the wrong type for this socket\n";
                                break;
                        case WSAESOCKTNOSUPPORT:
                                MidOutMsg="Specified socket type is not supported in this address family\n";
                                break;
                        default:
                                MidOutMsg="Unrecognized error\n";
                                break;
                }
        }
}

---

The problem was one of the network cards wasn't connected to anything and so the IP address being returned was "". So when I tried creating the socket, I was getting the error of WSAEADDRNOTAVAIL which isn't on the list of valid returns for the Create function.

The problem that I was having was the bad address was the first ip address and when I tried creating the second ip address, nothing could be created.

Now if the valid address was first, I was able to create it, but not if it was second.

I know I can solve the problem of making sure that the address is valid, but why was the second Create failing if the first Create had a "" for an address

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