将TCP服务器转换为UDP服务器

Question

因此，我试图从TCP服务器中创建Winsock UDP服务器，但我似乎无法让它正常工作。官方的winsock文档似乎没有涵盖UDP服务器(至少据我所能找到)。

正在工作的TCP服务器在这里：

#include <iostream>
#include <ws2tcpip.h>
#include <windows.h>

using namespace std;

int main()
{
    const char* port = "888";
    char message[50] = {0};

// Initialize WINSOCK
    WSADATA wsaData;
    WSAStartup(MAKEWORD(2,2), &wsaData);

// Create the listening socket
    SOCKET ListenSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); 
    SOCKET DataSocket;

// Initialize the sample struct and get another filled struct of the same type and old values
    addrinfo hints, *result(0); ZeroMemory(&hints, sizeof(hints));
    hints.ai_family   = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;
    hints.ai_flags    = AI_PASSIVE;

    getaddrinfo(0, port, &hints, &result);

// Bind the socket to the ip and port provided by the getaddrinfo and set the listen socket's type to listen
    bind(ListenSocket, result->ai_addr, (int)result->ai_addrlen);
    listen(ListenSocket, SOMAXCONN); // Only sets the type to listen ( doesn't actually listen )

// Free unused memory
    freeaddrinfo(result);

// Accept a connection
    DataSocket = accept(ListenSocket, 0, 0);
    cout << "Connected!" << endl << endl;

// Recieve data
    while(true){
        recv(DataSocket, message, 10, 0);
        cout << "Recieved: \n\t" << message << endl << endl;
        system("cls");
        Sleep(10);
    }

// Shutdown
    shutdown(DataSocket, SD_BOTH);
    shutdown(ListenSocket, SD_BOTH);
    WSACleanup();
    exit(0);
    return 0;
}

如何将其转换为可工作的UDP服务器？根据我的经验，仅仅改变协议和套接字并不能改变它。

代码更新：

const char* port = "888";
char message[50] = {0};

// Initialize WINSOCK
WSADATA wsaData;
WSAStartup(MAKEWORD(2,2), &wsaData);

// Create the listening socket
SOCKET DataSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); 

// Initialize the sample struct and get another filled struct of the same type and old values
addrinfo hints, *result(0); ZeroMemory(&hints, sizeof(hints));
hints.ai_family   = AF_INET;
hints.ai_socktype = SOCK_DGRAM;
hints.ai_protocol = IPPROTO_UDP;
hints.ai_flags    = AI_PASSIVE;

getaddrinfo(0, port, &hints, &result);

// Bind the socket to the ip and port provided by the getaddrinfo and set the listen socket's type to listen
bind(DataSocket, result->ai_addr, (int)result->ai_addrlen);
listen(DataSocket, SOMAXCONN); // Only sets the type to listen ( doesn't actually listen )

// Free unused memory
freeaddrinfo(result);

// Recieve data
while(true){
    int bytes = recvfrom(DataSocket, message, 20, 0, 0, 0);
}

Answer 1

若要将TCP服务器转换为UDP服务器，至少必须执行以下更改：

1. 将SOCK_STREAM替换为SOCK_DGRAM；IPPROTO_TCP替换为IPPROTO_UDP。
2. 删除listen和accept调用。
3. 将recv替换为recvfrom。
4. 将send替换为sendto。