Question

BOOL sendHTTPdata(char* data){
    //MessageBox(NULL,data, "aaa!",MB_ICONEXCLAMATION | MB_OK);

    char  *s=malloc(sizeof(char)*5000);
    WSADATA wsaData;
    SOCKET ConnectSocket = INVALID_SOCKET;
    struct addrinfo *result= NULL,
                    *ptr = NULL,
                    hints={0};
    char recvbuf[DEFAULT_BUFLEN];
    int iResult;
    int recvbuflen = DEFAULT_BUFLEN;

    // Initialize Winsock
    iResult = WSAStartup(MAKEWORD(2,2), &wsaData);
    if (iResult != 0) {
        //printf("WSAStartup failed with error: %d\n", iResult);
        MessageBox(NULL,"WSAStartup failed with error: %d\n", "Error!",MB_ICONEXCLAMATION | MB_OK);
        return FALSE;
    }

    memset (&hints, 0, (sizeof (hints)+1000));
    hints.ai_family = AF_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;
    // Resolve the server address and port
    //MessageBox(NULL,"test2", "Error!",MB_ICONEXCLAMATION | MB_OK);

    iResult = getaddrinfo("example.com","80", &hints, &result);
    //return FALSE;
    if ( iResult != 0) {
        sprintf(s, "getaddrinfo failed with error: %d\n",iResult);
        MessageBox(NULL,s, "Error!",MB_ICONEXCLAMATION | MB_OK);
        WSACleanup();
        return FALSE;
    }
    MessageBox(NULL,"test", "Error!",MB_ICONEXCLAMATION | MB_OK);
    // Attempt to connect to an address until one succeeds
    //return FALSE;
    for(ptr=result; ptr != NULL ;ptr=ptr->ai_next) {

        // Create a SOCKET for connecting to server
        ConnectSocket = socket(ptr->ai_family, ptr->ai_socktype, 
            ptr->ai_protocol);
        if (ConnectSocket == INVALID_SOCKET) {
           sprintf(s, "socket failed with error: %ld\n",WSAGetLastError());
        MessageBox(NULL,s, "Error!",MB_ICONEXCLAMATION | MB_OK);
        WSACleanup();
        return FALSE;
        }

        // Connect to server.
        iResult = connect( ConnectSocket, ptr->ai_addr, (int)ptr->ai_addrlen);
        if (iResult == SOCKET_ERROR) {
            closesocket(ConnectSocket);
            ConnectSocket = INVALID_SOCKET;
            continue;
        }
        break;
    }

    freeaddrinfo(result);

    if (ConnectSocket == INVALID_SOCKET) {
       MessageBox(NULL,"Unable to connect to server!\n", "Error!",MB_ICONEXCLAMATION | MB_OK);
        WSACleanup();
        return FALSE;

    }

    // Send an initial buffer
    iResult = send( ConnectSocket, data, (int)strlen(data), 0 );
    if (iResult == SOCKET_ERROR) {
        sprintf(s,"send failed with error: %d\n",WSAGetLastError());
        MessageBox(NULL,s, "Error!",MB_ICONEXCLAMATION | MB_OK);
        closesocket(ConnectSocket);
        WSACleanup();
        return FALSE;
    }

    //printf("Bytes Sent: %ld\n", iResult);
    sprintf(s,"Bytes Sent: %ld\n",iResult);
    MessageBox(NULL,s, "Error!",MB_ICONEXCLAMATION | MB_OK);

    // shutdown the connection since no more data will be sent
    iResult = shutdown(ConnectSocket, SD_SEND);
    if (iResult == SOCKET_ERROR) {
        //printf("shutdown failed with error: %d\n", WSAGetLastError());
        sprintf(s,"shutdown failed with error: %d\n", WSAGetLastError());
        MessageBox(NULL,s, "Error!",MB_ICONEXCLAMATION | MB_OK);

        closesocket(ConnectSocket);
        WSACleanup();
        return 1;
    }

    // Receive until the peer closes the connection
    do {

        iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
        if ( iResult > 0 )
        {
            MessageBox(NULL,recvbuf, "success!",MB_ICONEXCLAMATION | MB_OK);
        }
        else if ( iResult == 0 )
            MessageBox(NULL,"Connection closed\n", "Error!",MB_ICONEXCLAMATION | MB_OK);
        else {
            sprintf(s,"recv failed with error: %d\n", WSAGetLastError());
            MessageBox(NULL,s, "Error!",MB_ICONEXCLAMATION | MB_OK);
        }
    } while( iResult > 0 );

    // cleanup
    closesocket(ConnectSocket);
    WSACleanup();

    return TRUE;
}

When i compile it with Visual C++ 2010 gives Access violation error but if I compile it with Visual C++ 6.0 it works…

this is what i can see in error log:

First-chance exception at 0x1027d22f (msvcr100d.dll) in Work Time Managment.exe: 0xC0000005: Access violation writing location 0x00130000.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
First-chance exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
Unhandled exception at 0xfefefefe in Work Time Managment.exe: 0xC0000005: Access violation reading location 0xfefefefe.
The program '[1456] Work Time Managment.exe: Native' has exited with code 0 (0x0).

what is wrong… ? why cannt work getaddrinfo in Visual C++ 2010 ????
This libraries i use in my code:

#define WIN32_LEAN_AND_MEAN
#define _WSPIAPI_COUNTOF
#include "windows.h"
#include "winsock2.h"
#include "ws2tcpip.h"
#include "stdio.h"
#pragma comment (lib, "Ws2_32.lib")

Answer 1

This is a problem:

memset (&hints, 0, (sizeof (hints)+1000)); 

as it will be writing to 1000 bytes of memory it should not, causing undefined behaviour. The call to memset() is unrequired as hints has already been initialised. However, the correct use is:

memset (&hints, 0, sizeof(hints));

---

I think the problem is elsewhere in the code as getaddrinfo() executed successfully for me using VC2010. This is the source I used:

#include <winsock2.h>
#include <Ws2tcpip.h>
#include <stdio.h>
#include <string.h>

int main()
{
    WSADATA wsaData;
    struct addrinfo *result= NULL, hints={0}; 
    int iResult;

    iResult = WSAStartup(MAKEWORD(2,2), &wsaData);

    if (iResult != 0)
    {
        fprintf(stderr, "Startup failure: %d\n", iResult);
    }
    else
    {
        /* Identical behaviour with and without the memset(). 
        memset(&hints, 0, sizeof(hints)); */

        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;
        hints.ai_protocol = IPPROTO_TCP;

        iResult = getaddrinfo("localhost", "80", &hints, &result);
        if (0 != iResult)
        {
            fprintf(stderr, "failure: %d\n", iResult);
        }
        else
        {
            printf("Success\n");
        }

        WSACleanup();
    }
    return 0;
}