在c++中使用Winsock2时出现套接字创建编译错误

Question

编辑：

#undef UNICODE

#define WIN32_LEAN_AND_MEAN

#include <Windows.h>
#include <WinSock2.h>
#include <WS2tcpip.h>
#include <iostream>
#include <string>
#include <thread>

#pragma comment (lib, "Ws2_32.lib")

#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "1016"

//Globals
struct addrinfo *result = NULL;
struct addrinfo hints;

//Prototypes
int listenFunction();
int acceptFunction(SOCKET ListenSocket);

我最近开始重新编写一个tchat服务器，为了让代码更干净，我从来没有去工作过，但我遇到了一个让我有点困惑的错误。我知道如何解决这个问题，但我想知道它为什么要这样做。所以基本上，我有两个函数，我的主函数：

int main()
{
    int iResult;
    std::cout << "At the begginning of main." << std::endl;
    WSADATA wsaData;

    //Initialize winsock
    std::cout << "Initializing winsock..." << std::endl;
    iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
    if (iResult != 0)
    {
        std::cout << "WSAStartup failed." << std::endl;
        return 1;
    }
    std::cout << "Sucess" << std::endl;

    ZeroMemory(&hints, sizeof(hints));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;
    hints.ai_flags = AI_PASSIVE;

    std::cout << "Going into listenFunction()" << std::endl;
    listenFunction();

    return 0;
}

和我的listenFunction：

int listenFunction()
{
    int iResult;
    std::cout << "In Listening function" << std::endl;

    SOCKET ListenSocket = INVALID_SOCKET;

    std::cout << "Calling addrinfo()" << std::endl;
    iResult = getaddrinfo(NULL, DEFAULT_PORT, &hints, &result);
    if (iResult != 0){
        std::cout << "getaddrinfo() failed with error code : " << std::endl;
        WSACleanup();
        return -1;
    }

    //Create a SOCKET for connecting to the server
    std::cout << "Creating ListenSocket..." << std::endl;
    ListenSocket = socket(result->ai_family, result->ai_socktype, result->ai_protocol);
    if (ListenSocket == INVALID_SOCKET) {
        std::cout << "Socket failed with error : " << WSAGetLastError() << std::endl;
        freeaddrinfo(result);
        WSACleanup();
        return -1;
    }

    //Maybe setsockopt function here if bug

    //Setup the TCP listening socket
    std::cout << "Setting up the TCP listening socket..." << std::endl;
    iResult = bind(ListenSocket, result->ai_addr, (int)result->ai_addrlen);
    if (iResult == SOCKET_ERROR) {
        std::cout << "Bind failed with error : " << WSAGetLastError() << std::endl;
        freeaddrinfo(result);
        closesocket(ListenSocket);
        WSACleanup();
        return -1;
    }

    freeaddrinfo(result);

    std::cout << "Listening on ListenSocket..." << std::endl;
    //Listening
    iResult = listen(ListenSocket, SOMAXCONN);
    if (iResult == SOCKET_ERROR){
        std::cout << "Listen failed with error : " << WSAGetLastError() << std::endl;
        closesocket(ListenSocket);
        WSACleanup();
        return -1;
    }

    std::thread AcceptThread{ acceptFunction(ListenSocket) };

    return 0;
}

简单地说，当我在listenFunction中声明套接字时，我得到了这个错误：

Error   1   error C2064: term does not evaluate to a function taking 0 arguments

如果我复制相同的行并将其粘贴到main函数中，我就不会再得到那个错误(当然，我会得到listenFunction中的所有错误，因为它没有声明)。有没有办法解决这个问题，而不是在参数中传递它？

任何帮助都是非常感谢的，

民宿

Answer 1

您列出的错误不是由创建套接字引起的，而是由以下代码行引起的：

std::thread AcceptThread{ acceptFunction(ListenSocket) };

我不知道你在做什么，因为我不熟悉如何用大括号来初始化std::thread。也许是对Lambda的一种尝试？