connect function Error 10047 (winsock2)

Question

So I copied some test code from the MSDN site that uses basic windows socket functions. Here is the code:

#include "stdafx.h"

#ifndef UNICODE
#define UNICODE
#endif

#include <stdio.h>
#include <winsock2.h>
#include <ws2tcipip.h>
#include <wchar.h>


int main()
{

    int iResult = 0;

    //----------------------
    // Initialize Winsock
    WSADATA wsaData;
    iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
    if (iResult != 0) {
        wprintf(L"WSAStartup function failed with error: %d\n", iResult);
        return 1;
    }
    //----------------------
    // Create a SOCKET for connecting to server
    SOCKET ConnectSocket;
    ConnectSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (ConnectSocket == INVALID_SOCKET) {
        wprintf(L"socket function failed with error: %ld\n", WSAGetLastError());
        WSACleanup();
        return 1;
    }
    //----------------------
    // The sockaddr_in structure specifies the address family,
    // IP address, and port of the server to be connected to.

    int I = sizeof(sockaddr_in);
        sockaddr_in clientService;
    clientService.sin_family = AF_INET;     
        clientService.sin_port = htons(5000);
    in_addr *s = (in_addr*)malloc(sizeof(in_addr));
    s->s_addr = inet_addr("127.0.0.1");
    clientService.sin_addr = (in_addr_t)s;

    iResult = connect(ConnectSocket, (sockaddr*)&clientService,I);
    if (iResult == SOCKET_ERROR) {
        wprintf(L"connect function failed with error: %ld\n", WSAGetLastError());
        iResult = closesocket(ConnectSocket);
        if (iResult == SOCKET_ERROR)
            wprintf(L"closesocket function failed with error: %ld\n", WSAGetLastError());
        WSACleanup();
        return 1;
    }

    wprintf(L"Connected to server.\n");

    iResult = closesocket(ConnectSocket);
    if (iResult == SOCKET_ERROR) {
        wprintf(L"closesocket function failed with error: %ld\n", WSAGetLastError());
        WSACleanup();
        return 1;
    }

    WSACleanup();
    return 0;
}

The code compiles just fine. But when I run the program the command prompt screen displays the following error message:

connection failed with error: 10047

Now I know that Error 10047 indicates an error in the address structure. I tried using inet_pton but that leads to a segment error (memory access violation) as inet_pton uses the memcpy function. So what is going on here? Is the connect function improperly implemented? Maybe there is another way to specify the address structure.

Louis Ricci Louis Ricci · Accepted Answer · 2013-01-09T19:47:04

From MSDN: http://msdn.microsoft.com/en-us/library/windows/desktop/ms737625%28v=vs.85%29.aspx

sockaddr_in clientService;
clientService.sin_family = AF_INET;
clientService.sin_addr.s_addr = inet_addr("127.0.0.1");
clientService.sin_port = htons(27015);

Seems like your setting .sin_addr.s_addr in an ambiguous way.

If it turns out the above, isn't the problem, then perhaps you have IP6 protocols truned on but no IP4 which would be why AF_NET is failing and required AF_NET6.

connect function Error 10047 (winsock2)

2 Answers