0721,抄了都没看懂

client: socket -->  connect        -->send/recv-->close
server: sockket-->bind -->listen-->send/recv-->close

抄了都没看懂

//002.c
#include <func.h>

int main()
{
    //client
    int clientfd=socket(AF_INET,SOCK_STREAM,0);
    if(clientfd<0){error(1,0,"socket");}//miao1
    
    printf("client :%d\n",clientfd);

    struct sockaddr_in serveraddr;
    memset(&serveraddr,0,sizeof(serveraddr));
    serveraddr.sin_family=AF_INET;
    serveraddr.sin_port=htons(8080);
    serveraddr.sin_addr.s_addr=inet_addr("192.168.235.128");
    //sin_addr  你也是个结构体miao
    int  ret =connect(clientfd,(struct sockaddr*)&serveraddr,
                     sizeof(serveraddr));
    if(ret==-1){error(1,errno,"connect");}
    printf("connect sucess\n");

    //进行数据的接收和发送
    char buff[100]={0};//initialize

    //默认情况虾，recv函数也是一个阻塞式函数
    ret=recv(clientfd,buff,sizeof(buff),0);
    printf("rec:%d bytes\n",ret);
    printf("rec:%s \n",buff);

    //发送数据
    char msg[]="hello ,server";
    ret=send(clientfd,msg,strlen(msg),0);
    printf("send %d bytes.\n",ret);
    
    while(1);
    
    return 0;
}

//002sever.c
#include <func.h>

int main()
{
    //创建server的监听套接字
    int listenfd=socket(AF_INET,SOCK_STREAM,0);
    if(listenfd==-1){error(1,-1,"listen");}
    printf("listendfd=%d\n",listenfd);

    //设置套接字的属性,网络地址可以重用（before bind)
    int on=1;
    int ret=setsockopt(listenfd,SOL_SOCKET,SO_REUSEADDR,&on,sizeof(on));
    if(ret==-1){error(1,errno,"setsockopt");}

    struct sockaddr_in serveraddr;
    memset(&serveraddr,0,sizeof(serveraddr));
    serveraddr.sin_family=AF_INET;
    serveraddr.sin_port=htons(8080);
    serveraddr.sin_addr.s_addr=inet_addr("192.168.235.128");

    //human can see
    printf("%s:%d\n",inet_ntoa(serveraddr.sin_addr),
           ntohs(serveraddr.sin_port));
    //bind  绑定一个套接字和一个网络地址
    //只有服务器需要调用猫，暴露自己的网络地址
    //lient会被操作系统自动分配一个
    
    ret=bind(listenfd,(const struct sockaddr*)&serveraddr,
                 sizeof(serveraddr));
    if(ret==-1){error(1,errno,"bind");}

    //jianting client
    ret=listen(listenfd,1);
    printf("sever is listening.\n");

    while(1){
        struct sockaddr_in clientaddr;
        memset(&clientaddr,0,sizeof(clientaddr));
        socklen_t len=sizeof(clientaddr);
        printf("len :%d\n",len);
        //通过accpt的第二个参数可以获取到客户端的网络地址
        int perrfd=accept(listenfd,
                          (struct sockaddr*)&clientaddr,&len);
        //perrfd是listendfd的分身，主要用来和客户端交互
        printf("peerfd:%d\n",perrfd);
        printf("client addr:%s:%d\n",inet_ntoa(clientaddr.sin_addr),
               ntohs(clientaddr.sin_port));

        char buff[100]="hello.client";

        //sizeof(buff)==len
        //ret=send(perrfd,buff,strlen(buff),0);
        //字符穿一般使用strlen
        sleep(3);
        ret=recv(perrfd,buff,strlen(buff),0);
        printf("send %d bytes\n",ret);

        memset(buff,0,sizeof(buff));//clean massage
        ret=recv(perrfd,buff,sizeof(buff),0);
        printf("recv: %s\n",buff);
        
    }
    //关闭套接字
    close(listenfd);
    return 0;
}

xiaohuichen@xiaohuichen-virtual-machine:~/001/710$ ./002sever
listendfd=3
192.168.235.128:8080
./002sever: bind: Address already in use
xiaohuichen@xiaohuichen-virtual-machine:~/001/710$ ./002
client :3
connect sucess 

神经，抄错了喵

改了还是一样喵