帮我写个proactor的网络socket服务端c++的程序

好的，我可以帮您编写一个proactor的网络socket服务端c程序。以下是代码示例：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/epoll.h>

#define MAX_EVENTS 10
#define PORT 8888

int setnonblocking(int fd) {
    int flags = fcntl(fd, F_GETFL, );
    if (flags == -1) {
        return -1;
    }
    flags |= O_NONBLOCK;
    if (fcntl(fd, F_SETFL, flags) == -1) {
        return -1;
    }
    return ;
}

int main() {
    int listen_fd, conn_fd, epoll_fd, nfds, n, i;
    struct sockaddr_in serv_addr, cli_addr;
    socklen_t cli_len = sizeof(cli_addr);
    struct epoll_event ev, events[MAX_EVENTS];

    listen_fd = socket(AF_INET, SOCK_STREAM, );
    if (listen_fd == -1) {
        perror("socket");
        exit(EXIT_FAILURE);
    }

    memset(&serv_addr, , sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(PORT);

    if (bind(listen_fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) == -1) {
        perror("bind");
        exit(EXIT_FAILURE);
    }

    if (listen(listen_fd, SOMAXCONN) == -1) {
        perror("listen");
        exit(EXIT_FAILURE);
    }

    epoll_fd = epoll_create1();
    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);
    }

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

        for (i = ; i < nfds; i++) {
            if (events[i].data.fd == listen_fd) {
                conn_fd = accept(listen_fd, (struct sockaddr *)&cli_addr, &cli_len);
                if (conn_fd == -1) {
                    perror("accept");
                    continue;
                }

                if (setnonblocking(conn_fd) == -1) {
                    perror("setnonblocking");
                    exit(EXIT_FAILURE);
                }

                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");
                    exit(EXIT_FAILURE);
                }
            } else {
                do {
                    n = read(events[i].data.fd, buf, sizeof(buf));
                    if (n == -1) {
                        if (errno != EAGAIN) {
                            perror("read");
                            epoll_ctl(epoll_fd, EPOLL_CTL_DEL, events[i].data.fd, NULL);
                            close(events[i].data.fd);
                        }
                        break;
                    } else if (n == ) {
                        epoll_ctl(epoll_fd, EPOLL_CTL_DEL, events[i].data.fd, NULL);
                        close(events[i].data.fd);
                        break;
                    }

                    if (write(events[i].data.fd, buf, n) == -1) {
                        perror("write");
                        epoll_ctl(epoll_fd, EPOLL_CTL_DEL, events[i].data.fd, NULL);
                        close(events[i].data.fd);
                        break;
                    }
                } while (1);
            }
        }
    }

    return ;
}

希望这个程序能够帮助到您。