给我写一段简单的epoll 和 signal 的服务器-客户端代码示例

好的，以下是一个简单的 epoll 和 signal 的服务器-客户端代码示例：

服务器端代码：

#include <iostream>
#include <cstring>
#include <cstdlib>
#include <unistd.h>
#include <signal.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/epoll.h>
#include <netinet/in.h>

#define MAX_EVENTS 10
#define BUF_SIZE 256

using namespace std;

int main(int argc, char ** argv)
{
    if (argc != 2) 
    {
        cout << "Usage: " << argv[0] << " <port>" << endl;
        return 1;
    }

    int server_port = atoi(argv[1]);

    int server_sockfd;
    struct sockaddr_in server_addr;

    // 创建 Socket
    server_sockfd = socket(AF_INET, SOCK_STREAM, 0);

    // 设置地址重用
    int reuse = 1;
    setsockopt(server_sockfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse));

    // 设置地址和端口
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    server_addr.sin_port = htons(server_port);

    // 绑定 Socket
    bind(server_sockfd, (struct sockaddr *)&server_addr, sizeof(server_addr));

    // 监听 Socket
    listen(server_sockfd, 10);

    int epoll_fd, nfds;
    struct epoll_event ev, events[MAX_EVENTS];
    char buffer[BUF_SIZE];

    // 创建 epoll
    epoll_fd = epoll_create(10);

    // 添加 server_sockfd 到 epoll 中
    ev.events = EPOLLIN;
    ev.data.fd = server_sockfd;
    epoll_ctl(epoll_fd, EPOLL_CTL_ADD, server_sockfd, &ev);

    while (1)
    {
        // 等待事件发生
        nfds = epoll_wait(epoll_fd, events, MAX_EVENTS, -1);
        if (nfds == -1)
        {
            perror("epoll_wait");
            break;
        }

        // 处理事件
        for (int i = 0; i < nfds; i++)
        {
            if (events[i].data.fd == server_sockfd)
            {
                // 接受客户端连接请求
                int client_sockfd;
                struct sockaddr_in client_addr;
                socklen_t client_len = sizeof(client_addr);

                client_sockfd = accept(server_sockfd, (struct sockaddr *)&client_addr, &client_len);

                // 添加 client_sockfd 到 epoll 中
                ev.events = EPOLLIN | EPOLLRDHUP | EPOLLET;
                ev.data.fd = client_sockfd;
                epoll_ctl(epoll_fd, EPOLL_CTL_ADD, client_sockfd, &ev);
            }
            else if (events[i].events & EPOLLIN)
            {
                // 处理读事件
                int sockfd = events[i].data.fd;

                int n = read(sockfd, buffer, BUF_SIZE);

                if (n == 0)
                {
                    // 客户端关闭连接
                    close(sockfd);
                    epoll_ctl(epoll_fd, EPOLL_CTL_DEL, sockfd, &ev);
                }
                else if (n > 0)
                {
                    // 发送数据到客户端
                    write(sockfd, buffer, n);
                }
                else
                {
                    perror("read");
                }
            }
            else if (events[i].events & EPOLLRDHUP)
            {
                // 处理客户端关闭连接事件
                int sockfd = events[i].data.fd;

                close(sockfd);
                epoll_ctl(epoll_fd, EPOLL_CTL_DEL, sockfd, &ev);
            }
            else
            {
                // 处理其他事件
            }
        }
    }

    // 关闭 Socket
    close(server_sockfd);

    return 0;
}

客户端代码：

#include <iostream>
#include <cstring>
#include <cstdlib>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <signal.h>

#define BUF_SIZE 256

using namespace std;

int running = 1;

void sig_handle(int signo)
{
    if (signo == SIGINT)
    {
        cout << "Terminating client..." << endl;
        running = 0;
    }
}

int main(int argc, char ** argv)
{
    if (argc != 3)
    {
        cout << "Usage: " << argv[0] << " <server_ip> <server_port>" << endl;
        return 1;
    }

    int server_port = atoi(argv[2]);

    int client_sockfd;
    struct sockaddr_in server_addr;
    char buffer[BUF_SIZE];

    // 创建 Socket
    client_sockfd = socket(AF_INET, SOCK_STREAM, 0);

    // 设置地址和端口
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = inet_addr(argv[1]);
    server_addr.sin_port = htons(server_port);

    // 连接到服务器
    connect(client_sockfd, (struct sockaddr *)&server_addr, sizeof(server_addr));

    // 注册信号处理函数
    signal(SIGINT, sig_handle);

    // 循环读取用户输入并发送到服务器
    while (running)
    {
        memset(buffer, 0, BUF_SIZE);

        fgets(buffer, BUF_SIZE, stdin);

        int n = write(client_sockfd, buffer, strlen(buffer));

        if (n < 0)
        {
            perror("write");
            break;
        }

        n = read(client_sockfd, buffer, BUF_SIZE);

        if (n < 0)
        {
            perror("read");
            break;
        }

        buffer[n] = '\0';

        cout << "Server reply:" << buffer;
    }

    // 关闭 Socket
    close(client_sockfd);

    return 0;
}

希望这个代码示例能对您有所帮助。如果您有任何疑问，请随时问我。