DAY1 网络编程（TCP客户端服务器）

作业：

        TCP客户端服务器。

server服务器代码：

#include <myhead.h>
#define  IP "192.168.110.52"
#define PORT 8886
#define BACKLOG 20
int main(int argc, const char *argv[])
{
	int oldfd=socket(AF_INET,SOCK_STREAM,0);//IPV4通信  TCP通信协议
	if(oldfd==-1)
	{
		perror("socket");
		return -1;
	}
	//2.绑定IP和端口号
	struct sockaddr_in server=
	{
		.sin_family=AF_INET,//IPV4
		.sin_port=htons(PORT),//端口号转为网络字节序
		.sin_addr.s_addr=inet_addr(IP),//IP
	};
	if(bind(oldfd,(struct sockaddr *)&server,sizeof(server))==-1)
	{
		perror("bind");
		return -1;
	}
	//3.监听
	if(listen(oldfd,BACKLOG)==-1)
	{
		perror("listen");
		return -1;   
	}
	//4.接收客户端连接请求创建新的描述符用于通讯
	struct sockaddr_in client;//接收客户端信息的结构体
	socklen_t client_len=sizeof(client);//计算出结构体大小
	int newfd;
	newfd =accept(oldfd,(struct sockaddr*)&client,&client_len);
	if(newfd==-1)
	{
		perror("accept");
		return -1;
	}
	printf("%s发来连接请求\n",inet_ntoa(client.sin_addr));

	//5.循环收发信息
	char buff[1024];
	while(1)
	{
		memset(buff,0,sizeof(buff));
		int len=recv(newfd,buff,sizeof(buff),0);//0:非阻塞 MSG_DONTWAIT
		if(len==0)
		{
			printf("客户端断开连接\n");
			break;
		}
		printf("%s\n",buff);
		strcat(buff,"520");
		send(newfd,buff,sizeof(buff),0);
	}
	close(oldfd);
	close(newfd);
	return 0;
}

client客户端代码：

#include <myhead.h>
#define IP "192.168.110.52"
#define PORT 8886
int main(int argc, const char *argv[])
{
	int oldfd=socket(AF_INET,SOCK_STREAM,0);
	if(oldfd==-1)
	{
		perror("socket");
		return -1;
	}
	struct sockaddr_in server=
	{
		.sin_family=AF_INET,
		.sin_port=htons(PORT),
		.sin_addr.s_addr=inet_addr(IP),
	};
	if(connect(oldfd,(struct sockaddr *)&server,sizeof(server))==-1)
	{
		perror("connect");
		return -1;
	}
	char buff[1024];
	while(1)
	{
		fgets(buff,sizeof(buff),stdin);
		buff[strlen(buff)-1]='\0';
		send(oldfd,buff,sizeof(buff),0);
		int len=recv(oldfd,buff,sizeof(buff),0);
		if(len==0)
		{
			printf("服务器意外退出\n");
			break;
		}
		printf("接收服务器：%s\n",buff);
	}
    close(oldfd);
	return 0;
}

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