嵌入式学习day39

day38练习

用select方式，实现tcp点对点聊天

server.c

#include "head.h"

int tcp_accept(char const*ip,char const * port )
{
    //step1 socket 
    int fd = socket(AF_INET,SOCK_STREAM,0);

    if (fd < 0)
    {
        perror("socket fail");
        return -1;
    }

    printf("fd = %d\n",fd);

    struct sockaddr_in seraddr;
    //ip 192.168.0.150
    //port 50000
    bzero(&seraddr,sizeof(seraddr));
    seraddr.sin_family = AF_INET;
    seraddr.sin_port = htons(atoi(port));
    seraddr.sin_addr.s_addr = inet_addr(ip);

    if (bind(fd,(const struct sockaddr *)&seraddr,sizeof(seraddr)) < 0)
    {
        perror("connect fail");
        return -1;
    }
    if (listen(fd,5) < 0)
    {
        perror("listen fail");
        return -1;
    }

    int connfd = accept(fd,NULL,NULL);
    if (connfd < 0)
    {
        perror("accept fail");
        return -1;
    }
	return connfd;
}



int main(int argc, char const *argv[])
{
	if (argc != 3)
	{
		printf("Usage: %s <ip> <port>\n",argv[0]);
		return -1;
	}
	int connfd = tcp_accept(argv[1],argv[2]);
	if (connfd < 0)
	{
		printf("tcp_accept fail");
		return -1;
	}

	//1.准备表 
	fd_set readfds;
	FD_ZERO(&readfds);

	//2.添加 要监控的文件描述符
	FD_SET(0,&readfds);
	FD_SET(connfd,&readfds);

	//3.准备参数
	int maxfds = connfd + 1;
	fd_set backfds ;

	char buf[1024] = {0};

	while (1)
	{
		backfds = readfds;
		int ret = select(maxfds,&backfds,NULL,NULL,NULL);

		if (ret < 0)
		{
			perror("select fail");
			return -1;
		}

		int i = 0;
		for (i = 0; i < maxfds;++i)
		{
			if (FD_ISSET(i,&backfds))
			{
				if (i == 0)
				{
					printf(">");
					fgets(buf,sizeof(buf),stdin);
					write(connfd,buf,strlen(buf)+1);
					if (strncmp(buf,"quit",4) == 0)
					{
						close(connfd);
						exit(0);
					}

				}else 
				{
					read(connfd,buf,sizeof(buf));
					if (strncmp(buf,"quit",4) == 0)
					{
						close(connfd);
						exit(0);
					}
					printf("cli buf: %s\n",buf);

				}
			}
		}

	}
    return 0;
}

client.c