VC++ Winsock2 错误 10049。尝试构建 IRC 机器人

Question

我正在尝试将我的 IRC 机器人从 Python 移植到 C++，但在使用 Winsock2 时遇到了一些问题。我对 C/C++ 中的套接字相当陌生，并且大部分代码都是从各种教程拼凑而成的。我不断收到错误 10049 并且不知所措。任何帮助将不胜感激。谢谢！

port_ 设置为 6667，host_ 为“irc.rizon.net”

WSADATA wsaData;
int starterr = WSAStartup(MAKEWORD(2,2), &wsaData);
if (starterr != 0) {
    std::cout << "Error: " << WSAGetLastError() << " occurred!" << std::endl;
    WSACleanup();
    return 1;
}
std::cout << "WSAStartup Successful!" << std::endl;
socketfd_ = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
if (socketfd_ == INVALID_SOCKET) {
    std::cout << "Error: " << WSAGetLastError() << " occurred!" << std::endl;
    WSACleanup();
    return 1;
}
std::cout << "Socket Creation Successful!" << std::endl;

sockaddr_in anews;
anews.sin_port = htons(port_);
anews.sin_addr.s_addr = inet_addr(host_.c_str());
anews.sin_family = AF_INET;
if (connect(socketfd_,(sockaddr*)&anews, sizeof(anews)) == SOCKET_ERROR) {
    std::cout << "Error: " << WSAGetLastError() << " occurred!" << std::endl;
    WSACleanup();
    return 1;
}
std::cout << "Socket has connected successfuly!" << std::endl;
return 0;

Answer 1

inet_addr() 采用“x.x.x.x”形式的点式 IP 地址，您将主机名传递给它。

你可以使用gethostbyname():

hostent* host;
char* ip;

...

// Get the local host information
host= gethostbyname(host_.c_str());
ip= inet_ntoa(*(struct in_addr *)*host->h_addr_list);

sockaddr_in anews;
anews.sin_port = htons(port_);
anews.sin_addr.s_addr = inet_addr(ip);
anews.sin_family = AF_INET;

...

或者更简单的方法是使用 getaddrinfo()：

struct addrinfo *ai;

if(getaddrinfo(host_.c_str(), "6667", NULL, &ai) != 0)
    return 1;

socketfd_ = socket(ai->ai_family, SOCK_STREAM, 0);
if (socketfd_ == INVALID_SOCKET) {
    freeaddrinfo(ai);
    return 1
}

if (connect(socketfd_, ai->ai_addr, (int)ai->ai_addrlen) == SOCKET_ERROR) {
    closesocket(socketfd_);
    freeaddrinfo(ai);
    return 1;
}

...