select epoll

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/epoll.h>
#include <sys/socket.h>
#include <netinet/in.h>

#define MAX_EVENTS 10

int main() {
    int listen_fd, conn_fd, epoll_fd, nfds, n;
    struct epoll_event ev, events[MAX_EVENTS];
    struct sockaddr_in server_addr;

    listen_fd = socket(AF_INET, SOCK_STREAM, 0);
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(8080);
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    bind(listen_fd, (struct sockaddr*)&server_addr, sizeof(server_addr));
    listen(listen_fd, SOMAXCONN);

    epoll_fd = epoll_create1(0);
    if (epoll_fd == -1) {
        perror("epoll_create1");
        exit(EXIT_FAILURE);
    }

    ev.events = EPOLLIN;
    ev.data.fd = listen_fd;
    if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, listen_fd, &ev) == -1) {
        perror("epoll_ctl: listen_fd");
        exit(EXIT_FAILURE);
    }

    for (;;) {
        nfds = epoll_wait(epoll_fd, events, MAX_EVENTS, -1);
        if (nfds == -1) {
            perror("epoll_wait");
            exit(EXIT_FAILURE);
        }

        for (n = 0; n < nfds; ++n) {
            if (events[n].data.fd == listen_fd) {
                conn_fd = accept(listen_fd, (struct sockaddr*)NULL, NULL);
                if (conn_fd == -1) {
                    perror("accept");
                    continue;
                }
                ev.events = EPOLLIN | EPOLLET;
                ev.data.fd = conn_fd;
                if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, conn_fd, &ev) == -1) {
                    perror("epoll_ctl: conn_fd");
                    close(conn_fd);
                }
            } else {
                // 处理客户端数据
                // ...
            }
        }
    }

    close(listen_fd);
    close(epoll_fd);
    return 0;
}