linux下tcp多进程案例

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <signal.h>

void sigchld_handler(int sig) {
    while (waitpid(-1, NULL, WNOHANG) > 0);
}

int main() {
    int server_fd, new_socket;
    struct sockaddr_in address;
    int addrlen = sizeof(address);

    // 创建socket
    if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == 0) {
        perror("socket failed");
        exit(EXIT_FAILURE);
    }

    // 绑定地址和端口
    address.sin_family = AF_INET;
    address.sin_addr.s_addr = INADDR_ANY;
    address.sin_port = htons(8080);

    if (bind(server_fd, (struct sockaddr *)&address, sizeof(address)) < 0) {
        perror("bind failed");
        exit(EXIT_FAILURE);
    }

    // 监听连接
    if (listen(server_fd, 3) < 0) {
        perror("listen");
        exit(EXIT_FAILURE);
    }

    // 处理僵尸进程
    signal(SIGCHLD, sigchld_handler);

    while (1) {
        // 接受新连接
        if ((new_socket = accept(server_fd, (struct sockaddr *)&address, (socklen_t*)&addrlen)) < 0) {
            perror("accept");
            exit(EXIT_FAILURE);
        }

        pid_t pid = fork();
        if (pid == 0) { // 子进程
            close(server_fd); // 关闭监听socket
            char buffer[1024] = {0};
            read(new_socket, buffer, 1024);
            printf("Received: %s\n", buffer);
            send(new_socket, "Hello from server", strlen("Hello from server"), 0);
            close(new_socket);
            exit(0);
        } else if (pid > 0) { // 父进程
            close(new_socket); // 关闭客户端socket
        } else {
            perror("fork");
        }
    }

    return 0;
}