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c++windowsgethostbyname

Problems with gethostbyname c++

I've this code made in c++ to connect to a server but every time I try "gethostbyname" the value is null(or optimized away and not available).

WSADATA wsaData;
if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
    cout << "WSAStartup failed.\n";
    system("pause");
    return 1;
}
hostent *host = gethostbyname("www.example.com");

I've tried hostent as volatile but still gives null. Is there any other way to make this work? I've tried too Optimization disabled but keeps giving null.

Solution

  • host is null on error. Check the return value of WSAGetLastError() to figure out whats wrong.

    Try calling ping www.example.com in a cmd shell to check whether the target is reachable from your machine.

    To not optimize add:

    if(host!=NULL && host->h_name)
    cout << "host: " << host->h_name << std::endl;

    Don't store pointers returned by gethostbyname(). They are overridden on the next call by the same thread.