网络编程day2

 TCP服务器

#include 
#include 
#include 
#include 
#include 

#define ERR_MSG(msg) do{\
		fprintf(stderr,"__%d__",__LINE__);\
		perror("msg");\
}while(0)

#define PORT 6666
#define IP "192.168.114.87"

int main(int argc, const char *argv[])
{
	//创建流式套接字　socket
	int sfd = socket(AF_INET,SOCK_STREAM,0);
	if(sfd < 0)
	{
		ERR_MSG("socket");
		return -1; 
	}
	printf("socket create success sfd=%d\n",sfd);
	//允许端口快速的被复用
	int reuse = 1;
	if(setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse))<0 )
	{
		ERR_MSG("setsockopt");
		return -1;
	}
	printf("允许端口快速的被复用\n");
	
	//填充地址信息结构体给bind函数绑定
	//真是的地址信息结构体根据地址族指定　AF_INET:man 7 ip
	struct sockaddr_in sin;
	sin.sin_family 		= AF_INET;  //必须填AF_INFT
	sin.sin_port 		=htons(PORT);//端口号的网络字节序
	sin.sin_addr.s_addr =inet_addr(IP);//本机IP

	//绑定服务器的地址信息-->必须绑定bind
	if(bind(sfd, (struct sockaddr*)&sin, sizeof(sin)) < 0)
	{
		ERR_MSG("bind");
		return -1;
	}
	printf("bind success\n");
	
	//将套接字设置为被动监听状态 listen
	if(listen(sfd,128) < 0)
	{
		ERR_MSG("listen");
		return -1;
	}
	printf("listen success\n");

	int newfd = -1;
	struct sockaddr_in cin;
	socklen_t addrlen = sizeof(cin);
	
	//获取一个已经完成的客户端信息，生成一个新的文件描述符 accept
	newfd = accept(sfd,(struct sockaddr*)&cin,&addrlen);
	if(newfd < 0)
	{
		ERR_MSG("newfd");
		return -1;
	}
	printf("[%s:%d]客户端链接成功 newfd=%d\n",\
			inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd);

	char buf[128] = "";
	ssize_t res = 0;
	while(1)
	{
		//清空字符串
		bzero(buf,sizeof(buf));

		//接收
		res = recv(newfd, buf, sizeof(buf), 0);
		if(res < 0)
		{
			ERR_MSG("recv");
			return -1;
		}
		else if(res == 0)
		{
			printf("[%s:%d]客户端下线 newfd=%d\n",\
			inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd);
			break;
		}
		printf("[%s:%d] newfd=%d : %s\n",\
			inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),newfd,buf);
		//发送
		strcat(buf,"hello");
		if(send(newfd, buf, sizeof(buf),0) < 0)
		{
			ERR_MSG("send");
			return -1;
		}
		printf("send success\n");
	}
	//关闭文件描述符
	close(newfd);
	if(close(sfd) < 0)
	{
		ERR_MSG("close");
		return -1;
	}
	return 0;
}

 

 TCP客户端

#include 
#define ERR_MSG(msg) do{\
fprintf(stderr,"__%d__:",__LINE__);\
perror(msg);\
}while(0)

#define PORT 6666
#define IP "192.168.114.87"

int main(int argc, const char *argv[])
{
	int cfd = socket(AF_INET, SOCK_STREAM, 0);
	if(cfd < 0)
	{
		ERR_MSG("socket");
		return -1;
	}
	printf("socket create success cfd=%d\n",cfd);

	struct sockaddr_in sin;
	sin.sin_family = AF_INET;
	sin.sin_port = htons(PORT);
	sin.sin_addr.s_addr = inet_addr(IP);

	//连接指定服务器 connect
	if(connect(cfd, (struct sockaddr*)&sin, sizeof(sin)) < 0)
	{
		ERR_MSG("connect");
		return -1;
	}
	printf("coonnect success\n");
	
	char buf[128] = "";
	ssize_t res = 0;
	while(1)
	{
		//清空字符串
		bzero(buf, sizeof(buf));
		printf("请输入：");
		fgets(buf, sizeof(buf),stdin);
		buf[strlen(buf)-1] = 0;

		//发送
		if(send(cfd, buf, sizeof(buf),0) < 0)
		{
			ERR_MSG("send");
			return -1;
		}
		printf("send success\n");

		bzero(buf, sizeof(buf));

		//接受
		res = recv(cfd, buf, sizeof(buf), 0);
		if(res < 0)
		{
			ERR_MSG("recv");
			return -1;
		}
		else if(res == 0)
		{
			printf("服务器下线 cfd=%d\n",cfd);
			break;
		}
		printf("cfd=%d : %s\n",cfd,buf);
	}

	//关闭文件描述符
	if(close(cfd) < 0)
	{
		ERR_MSG("close");
		return -1;
	}

	return 0;
}

UDP服务器

#include 

#define ERR_MSG(msg) do{\
fprintf(stderr,"__%d__:",__LINE__);\
perror(msg);\
}while(0)

#define PORT 6666
#define IP "192.168.114.87"

int main(int argc, const char *argv[])
{
	//创建报式套接字　socket
	int sfd = socket(AF_INET, SOCK_DGRAM, 0);
	if(sfd < 0)
	{
		ERR_MSG("socket");
		return -1;
	}
	printf("socket create success sfd=%d\n",sfd);

	struct sockaddr_in sin;
	sin.sin_family 		= AF_INET;
	sin.sin_port 		= htons(PORT);
	sin.sin_addr.s_addr = inet_addr(IP);

	//绑定地址信息结构体--->bind
	if(bind(sfd,(struct sockaddr*)&sin, sizeof(sin)) <0 )
	{
		ERR_MSG("bind");
		return -1;
	}
	printf("bind success\n");

	char buf[128] = "";
	struct sockaddr_in cin;
	socklen_t addrlen = sizeof(buf);

	while(1)
	{
		bzero(buf,sizeof(buf));
		//接受数据
		if(recvfrom(sfd, buf, sizeof(buf),0,(struct sockaddr*)&cin,&addrlen) < 0 )
		{
			ERR_MSG("recvfrom");
			return -1;
		}
		printf("[%s:%d] : %s\n",inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),buf);

		//发送数据
		strcat(buf,"*_*");
		if(sendto(sfd,buf,sizeof(buf),0,(struct sockaddr*)&cin,sizeof(cin)) < 0)
		{
			ERR_MSG("sendto");
			return -1;
		}
		printf("sendto success\n");
	}

	//关闭套接字
	close(sfd);

	return 0;
}

UDP客户端

#include 
#define ERR_MSG(msg) do{\
fprintf(stderr,"__%d__:",__LINE__);\
perror(msg);\
}while(0)

#define PORT 6666
#define IP "192.168.114.87"

int main(int argc, const char *argv[])
{
	//创建报式套接字  socket
	int sfd = socket(AF_INET, SOCK_DGRAM, 0);
	if(sfd < 0)
	{
		ERR_MSG("socket");
		return -1;
	}
	struct sockaddr_in sin;
	sin.sin_family = AF_INET;
	sin.sin_port = htons(PORT);
	sin.sin_addr.s_addr = inet_addr(IP);

	char buf[128] = "";
	socklen_t addrlen = sizeof(sin);

	while(1)
	{
		bzero(buf,sizeof(buf));
		printf("请输入>>>");
		fgets(buf, sizeof(buf),stdin);
		buf[strlen(buf)-1] = 0;

		//发送数据
		if(sendto(sfd, buf, sizeof(buf),0, (struct sockaddr*)&sin,sizeof(sin)) < 0)
		{
			ERR_MSG("sendto");
			return -1;
		}
		printf("sendto success\n");

		//接受数据
		if(recvfrom(sfd,buf,sizeof(buf),0,(struct sockaddr*)&sin,&addrlen) < 0)
		{
			ERR_MSG("recvfrom");
			return -1;
		}
	}
	
	//关闭套接字
	close(sfd);
	
	return 0;
}