socket 缓存区大小问题，高手求进

2014-01-14 10:48:07 521 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

socket之send与发送缓冲区大小的关系关于send函数在发送的数据长度大于发送缓冲区大小，或者大于发送缓冲区剩余大小时，socket会怎么反应。参见这篇博客的两种说法http://blog.csdn.net/gukesdo/article/details/7295592 自己做了个测试，服务器只起socket在侦听,不recv, 也不send. //ubuntu10.04 32bit #include #include 阅读详情

#include "header.h"



#define MAXBUF 1024

typedef struct sockaddr SA;



int main(void)

{

	int socketfd,socketfd_server;

	struct sockaddr_in serveraddr,clientaddr;

	char buffer[MAXBUF];

	socklen_t addrlen;

	int n;



	if((socketfd=socket(AF_INET,SOCK_STREAM,0)) == -1)

	{

		perror("socket fail");

		exit(-1);

	}

  

	memset(&serveraddr,0,sizeof(serveraddr));

	serveraddr.sin_family=AF_INET;

	serveraddr.sin_port=htons(8000);

	serveraddr.sin_addr.s_addr=inet_addr("127.0.0.1");

	

	if(bind(socketfd,(SA *)&serveraddr,sizeof(serveraddr)) == -1)

	{

		perror("bind fail");

		exit(-1);

	}

	if(listen(socketfd,10) == -1)

	{

		perror("listen fail");

		exit(-1);

	}

	addrlen = sizeof(clientaddr);

	if((socketfd_server=accept(socketfd,(SA *)&clientaddr,&addrlen)) == -1) //接收到客户端的消息

	{

		perror("accept fail");

		exit(-1);

	}

	printf("a new connection :%d\n",socketfd_server);  //打印socket连接套接字



	int s_length;

	int opt_l = sizeof s_length;



	getsockopt(socketfd_server,SOL_SOCKET,SO_RCVBUF,&s_length,(socklen_t *)&opt_l); //输出接收缓冲区大小

	printf("recv buffer = %d\n",s_length);



	sleep(3000);

	exit(0);

}

#include "header.h" 



#define MAXBUF 32768 

typedef struct sockaddr SA;



int main()

{

	int socketfd;

	char client_buffer[MAXBUF];

	struct sockaddr_in serveraddr,clientaddr; 





	if((socketfd=socket(AF_INET,SOCK_STREAM,0)) == -1) //调用TCP接口，创建套接字

	{

		perror("socket fail");

		exit(-1);

	}

	

	serveraddr.sin_family=AF_INET;

	serveraddr.sin_port=htons(8000);

	serveraddr.sin_addr.s_addr=inet_addr("127.0.0.1");

	 

	if(connect(socketfd,(struct sockaddr *)&serveraddr,sizeof(serveraddr)) == -1)  //连接服务器套接字 connect（）

	{

		perror("connect fail");

		exit(-1);

	}



	int s_length;

	socklen_t optl = sizeof s_length;



	getsockopt(socketfd,SOL_SOCKET,SO_SNDBUF,&s_length,&optl);     //获得连接套接字发送端缓冲区的信息

	printf("send buffer = %d\n",s_length);                         // 发送缓冲区的大小



	getsockopt(socketfd,SOL_SOCKET,SO_RCVBUF,&s_length,&optl);      //获得连接套接字的接收端的缓冲区信息

	printf("recv buffer = %d\n",s_length);                            //打印接收端缓冲区大小



	int i = 0;

	int sum = 0;

	while(1){

		memset(client_buffer,'\0',sizeof(client_buffer));                 //清空缓冲区的数据

		sprintf(client_buffer,"the message is %d\n",i++);			            

		if(write(socketfd,client_buffer,MAXBUF) < 0)                      //写入缓冲区

		{

			perror("write fail");

			exit(-1);

		}



		sum += MAXBUF;                                                    

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

	}



	close(socketfd);	

}