利用recv函数实现C++服务器接收数据

下面是一个简单的C++服务器端程序，利用recv函数接收数据：

#include <iostream>#include <cstring>#include <sys/socket.h>#include <netinet/in.h>int main() {    // 创建socket    int server_fd = socket(AF_INET, SOCK_STREAM, 0);    if (server_fd == -1) {        std::cerr << "Error creating socket" << std::endl;        return 1;    }    // 绑定端口    struct sockaddr_in server_addr;    server_addr.sin_family = AF_INET;    server_addr.sin_addr.s_addr = INADDR_ANY;    server_addr.sin_port = htons(8888);    if (bind(server_fd, (struct sockaddr *)&server_addr, sizeof(server_addr)) < 0) {        std::cerr << "Bind failed" << std::endl;        return 1;    }    // 监听端口    listen(server_fd, 3);    // 接受连接    int client_fd;    struct sockaddr_in client_addr;    int addr_len = sizeof(client_addr);    client_fd = accept(server_fd, (struct sockaddr *)&client_addr, (socklen_t *)&addr_len);    // 接收数据    char buffer[1024] = {0};    int valread = recv(client_fd, buffer, 1024, 0);        std::cout << "Received: " << buffer << std::endl;    return 0;}

这个程序创建一个服务器端socket，绑定端口，监听端口，并接受连接。接受到连接后，利用recv函数从客户端接收数据，并输出到控制台。