socket测试（多线程，课上测试）

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <pthread.h>

#define BUFFER_SIZE 1024

void *handle_client(void *arg);
void send_daytime(int client_fd);

int main(int argc, char *argv[]) {
    int server_fd, client_fd, port;
    struct sockaddr_in server_addr, client_addr;
    socklen_t addr_len = sizeof(struct sockaddr_in);
    pthread_t tid;

    if (argc != 2) {
        printf("Usage: %s [port]\n", argv[0]);
        return 1;
    }

    port = atoi(argv[1]);

    server_fd = socket(AF_INET, SOCK_STREAM, 0);
    if (server_fd < 0) {
        perror("socket");
        return 1;
    }

    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(port);
    server_addr.sin_addr.s_addr = INADDR_ANY;

    if (bind(server_fd, (struct sockaddr *)&server_addr, addr_len) < 0) {
        perror("bind");
        return 1;
    }

    if (listen(server_fd, 5) < 0) {
        perror("listen");
        return 1;
    }

    while (1) {
        client_fd = accept(server_fd, (struct sockaddr *)&client_addr, &addr_len);
        if (client_fd < 0) {
            perror("accept");
            continue;
        }

        pthread_create(&tid, NULL, handle_client, (void *)&client_fd);
        pthread_detach(tid);
    }

    close(server_fd);
    return 0;
}

void *handle_client(void *arg) {
    int client_fd = *((int *)arg);
    char buffer[BUFFER_SIZE];

    send_daytime(client_fd);

    while (1) {
        memset(buffer, 0, BUFFER_SIZE);
        if (recv(client_fd, buffer, BUFFER_SIZE, 0) <= 0) {
            break;
        }
        printf("Received: %s\n", buffer);
    }

    close(client_fd);
    return NULL;
}

void send_daytime(int client_fd) {
    char buffer[BUFFER_SIZE];
    time_t rawtime;
    struct tm *timeinfo;

    time(&rawtime);
    timeinfo = localtime(&rawtime);

    snprintf(buffer, BUFFER_SIZE, "客户端IP：%lu\n客户端PID：%lu\n服务器tid：%lu\n服务器实现者学号：20211116\n当前时间：%02d：%02d：%02d\n",
              inet_addr("127.0.0.1"),
              getpid(),
              pthread_self(),
              buffer);

    send(client_fd, buffer, strlen(buffer), 0);
}

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

#define BUFFER_SIZE 1024

void send_message(int server_fd, const char *message);

int main(int argc, char *argv[]) {
    int client_fd;
    struct sockaddr_in server_addr;
    char buffer[BUFFER_SIZE];

    if (argc != 2) {
        printf("Usage: %s [IP_address]\n", argv[0]);
        return 1;
    }

    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(13116); // DAYTIME port
    inet_aton(argv[1], &server_addr.sin_addr);

    client_fd = socket(AF_INET, SOCK_STREAM, 0);
    if (client_fd < 0) {
        perror("socket");
        return 1;
    }

    if (connect(client_fd, (struct sockaddr *)&server_addr, sizeof(server_addr)) < 0) {
        perror("connect");
        close(client_fd);
        return 1;
    }

    send_message(client_fd, "GET DAYTIME\n");

    while (1) {
        memset(buffer, 0, BUFFER_SIZE);
        if (recv(client_fd, buffer, BUFFER_SIZE, 0) <= 0) {
            break;
        }
        printf("Received: %s\n", buffer);
    }

    close(client_fd);
    return 0;
}

void send_message(int server_fd, const char *message) {
    send(server_fd, message, strlen(message), 0);
}