linux网络编程-TCP服务端

#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <pthread.h>
#include <semaphore.h>
#include <termios.h>
#include <sys/stat.h>
#include <fcntl.h>
//使用多线程解决并发
//pthread_attr_setdetachstate(pthread_attr_t *attr, int detachstate);
//为什么选择多线程解决并发问题,而不选择多进程
void serial_port_init(int fd);
void *pthread_fun(void *args)
{
    int *cidp = (int *)args;
    int cid = *cidp;
    char buf[128] = "";
    int count = -1;
    //5.发送或接收数据:send(),write()/recv(),read();
    while (strncmp(buf, "quit", 4))
    {
        read(cid, buf, sizeof(buf));
        printf("接收到:%s\n", buf);
        write(cid, buf, strlen(buf));
        memset(buf, 0, sizeof(buf));
    }
    //6.关闭套接字:close();
    shutdown(cid, SHUT_RDWR);
    close(cid);
}

int main(int argc, char **argv)
{
    if (argc < 3)
    {
        printf("usage : ./a.out ip port\n");
        return -1;
    }

    int sid = socket(AF_INET, SOCK_STREAM, 0);
    if (sid < 0)
    {
        perror("socket error");
        return -1;
    }

    //2.绑定到本机ip和端口号bind();
    struct sockaddr_in saddr = {0};
    saddr.sin_family = AF_INET;
    saddr.sin_port = htons(atoi(argv[2]));
    saddr.sin_addr.s_addr = inet_addr(argv[1]);
    int reuseaddr = 1;
    if (setsockopt(sid, SOL_SOCKET, SO_REUSEADDR, &reuseaddr, sizeof(reuseaddr)) < 0) //设置地址复用
    {
        perror("reuseaddr error");
        close(sid);
        return -1;
    }

    //端口复用
    if (bind(sid, (struct sockaddr *)&saddr, sizeof(saddr)) < 0)
    {
        perror("bind error: port binded");
        close(sid);
        return -1;
    }

    //3.把套接字设置为监听状态listen();
    if (listen(sid, 10) < 0)
    {
        perror("listen error");
        close(sid);
        return -1;
    }

    //4.等待客户端连接请求:accept();
    int cid = -1;
    pthread_t tid;

    //设置线程分离
    pthread_attr_t attr;
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);

    //当有客户端连接时，会有两个线程:主线程处理客户端连接请求，并创建一个子线程与网络客户端交互,子线程:负责与网络客户端交互
    while (1)
    {
        cid = accept(sid, NULL, NULL);
        if (cid < 0)
        {
            perror("accept error");
            continue;
        }

        pthread_create(&tid, &attr, pthread_fun, &cid); //创建子线程
    }
    close(sid);
}