[第一版]最简单的发送与接收

server

最大连接数为10,监听13号端口,当有客户端连接上来时,打印客户端的相关信息,同时向客户端发送当前服务器时间

#include "unp.h"
#include <time.h>
 
int main(int argc, char *argv[]){
    int listenfd,connfd;
    socklen_t len;
    struct sockaddr_in servaddr,cliaddr;
    char buff[MAXLINE];
    time_t ticks;
 
    listenfd=Socket(AF_INET,SOCK_STREAM,0);
 
    bzero(&servaddr,sizeof(servaddr));
    servaddr.sin_family=AF_INET;
    servaddr.sin_addr.s_addr=htonl(INADDR_ANY);
    servaddr.sin_port=htons(13);
 
    Bind(listenfd,(struct sockaddr *)&servaddr,sizeof(servaddr));
 
    Listen(listenfd,10);
 
    for(;;){
        len=sizeof(cliaddr);
        connfd=Accept(listenfd,(struct sockaddr *)&cliaddr,&len);
        printf("connection from %s, port %d
",
                inet_ntop(AF_INET,&cliaddr.sin_addr,buff,sizeof(buff)),
                ntohs(cliaddr.sin_port));
        ticks=time(NULL);
        snprintf(buff,sizeof(buff),"%.24s
",ctime(&ticks));
        write(connfd,buff,strlen(buff));
 
        Close(connfd);
    }
}

client

连接到服务端,连接完成后只接受不发送信息,收到第一条信息后打印并退出

#include "unp.h"
 
int main(int argc,char *argv[]){
    int sockfd;
    struct sockaddr_in servaddr;
 
    if(argc != 2)
        err_quit("usage: client <ip address>");
 
    sockfd=Socket(AF_INET,SOCK_STREAM,0);
 
    bzero(&servaddr,sizeof(servaddr));
    servaddr.sin_family=AF_INET;
    servaddr.sin_port=htons(13);
    inet_pton(AF_INET,argv[1],&servaddr.sin_addr);
 
    Connect(sockfd,(struct sockaddr *)&servaddr,sizeof(servaddr));
 
    char buff[1024]={0};
    read(sockfd,buff,1024);
    printf("received: %s",buff);
    exit(0);
}