C语言网络编程：面向未来的新兴网络技术

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

int main() {
    // 创建套接字
    int server_socket = socket(AF_INET, SOCK_STREAM, 0);
    if (server_socket < 0) {
        perror("创建套接字失败");
        return -1;
    }

    // 绑定套接字
    struct sockaddr_in server_addr;
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = INADDR_ANY;
    server_addr.sin_port = htons(7000);
    if (bind(server_socket, (struct sockaddr *)&server_addr, sizeof(server_addr)) < 0) {
        perror("绑定套接字失败");
        close(server_socket);
        return -1;
    }

    // 监听套接字
    if (listen(server_socket, SOMAXCONN) < 0) {
        perror("监听套接字失败");
        close(server_socket);
        return -1;
    }

    // 接受连接
    struct sockaddr_in client_addr;
    socklen_t addrlen = sizeof(client_addr);
    int client_socket = accept(server_socket, (struct sockaddr *)&client_addr, &addrlen);
    if (client_socket < 0) {
        perror("接受连接失败");
        close(server_socket);
        return -1;
    }

    // 发送消息
    char message[] = "Hello World!";
    if (send(client_socket, message, sizeof(message), 0) < 0) {
        perror("发送消息失败");
        close(client_socket);
        close(server_socket);
        return -1;
    }

    // 关闭套接字
    close(client_socket);
    close(server_socket);

    return 0;
}