How to use the select function with socket in c under windows platform

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C

#include "stdafx.h"
#include <winsock2.h>
#include <stdlib.h>
int main(int argc, char* argv[])
{
	SOCKET SocketDescripter,AcceptSocket;//,ListenSocket;	
	WSADATA wsadataValue;
	WORD wData=MAKEWORD(2,2);
	WSAStartup(wData,&wsadataValue);
	DWORD dvalue;

	fd_set *readfds;

//	struct timeval *timevalue;
	/*a=10;	
	timevalue->tv_sec=a;
	
	timevalue->tv_sec=30;*/

	SocketDescripter=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
	if(SocketDescripter==SOCKET_ERROR)
	{
		printf("error");
		WSACleanup();
		return 0;
	}
	else
	{
		printf("\n Sucess\n");
	}
	sockaddr_in sockap;
	sockap.sin_family=AF_INET;
	sockap.sin_port=htons(10000);
	sockap.sin_addr.s_addr=inet_addr("127.0.0.1");
	bind(SocketDescripter,(sockaddr*)&sockap,sizeof(sockap));
	listen(SocketDescripter,2);
	unsigned long lValue=1;
		if(0==ioctlsocket(SocketDescripter, FIONBIO,&lValue))
		{
			printf("the io control is sucessfully done\n");
		}
		FD_ZERO(&readfds);
		
		FD_SET(SocketDescripter,&readfds);
	
		dvalue=select(NULL,readfds,NULL,NULL,NULL);
		
		if(FD_ISSET(SocketDescripter,&readfds)==0)
		{
			int size=sizeof(SocketDescripter);
			AcceptSocket=accept(SocketDescripter,(sockaddr*)&SocketDescripter,&size);
			//ioctlsocket(AcceptSocket,FIONBIO,&lValue);
			char buffer[1024];
			printf("i am here");
			recv(AcceptSocket,buffer,sizeof(buffer),NULL);

		}
	return 0;
}

i try like that..

i don't know how to use the select. i studied the msdn website about the basic syntax and try..

can you teach me how to use during a client server application..

i keep on trying that area..

.. please help me..

Posted 14-Jul-11 20:43pm

@BangIndia

Updated 14-Jul-11 21:14pm

Sergey Alexandrovich Kryukov

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R. Erasmus · Answer 1 · 2011-07-14T21:05:00

Solution 1

Check out http://shoe.bocks.com/net/[^]

Posted 14-Jul-11 21:05pm

R. Erasmus

Comments

Sergey Alexandrovich Kryukov 15-Jul-11 3:22am

It looks like the usage is explained in the referenced article, my 5.
--SA

@BangIndia 15-Jul-11 3:31am

Thanks you sir..from you help i done the program sir..

my program is::

// select.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <winsock2.h>
#include <stdlib.h>
int main(int argc, char* argv[])
{
SOCKET SocketDescripter,AcceptSocket;//,ListenSocket;
WSADATA wsadataValue;
WORD wData=MAKEWORD(2,2);
WSAStartup(wData,&wsadataValue);
DWORD dvalue;
TIMEVAL timeout;

fd_set *readfds;

// struct timeval *timevalue;
/*a=10;
timevalue->tv_sec=a;

timevalue->tv_sec=30;*/
int iListenvalue;
SocketDescripter=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
if(SocketDescripter==SOCKET_ERROR)
{
printf("error");
WSACleanup();
return 0;
}
else
{
printf("\n Sucess\n");
}

sockaddr_in sockap,clientcon;
sockap.sin_family=AF_INET;
sockap.sin_port=htons(10000);
sockap.sin_addr.s_addr=inet_addr("127.0.0.1");

if(SOCKET_ERROR==bind(SocketDescripter,(sockaddr*)&sockap,sizeof(sockap)))
{
printf("\bBinding error\n");
return 1;
}

iListenvalue = listen(SocketDescripter,2);

if(iListenvalue != 0)
{
printf("The socket listening error\n");
closesocket(SocketDescripter);
WSACleanup();
}

unsigned long lValue=1;
if(0==ioctlsocket(SocketDescripter, FIONBIO,&lValue))
{
printf("the io control is sucessfully done\n");
}
while(1)
{
FD_ZERO(&readfds);

FD_SET(SocketDescripter,&readfds);
timeout.tv_sec=30;
timeout.tv_usec=0;
dvalue=select(4,readfds,NULL,NULL,&timeout);
if(dvalue<0)
{
printf("select error\n");
}
else
{
printf("\nSelect is sucessful\n\n");
}
if(FD_ISSET(SocketDescripter,&readfds))
{
printf("waiting for client\n");
int size=sizeof(clientcon);
AcceptSocket=accept(SocketDescripter,(struct sockaddr*)&clientcon,&size);
if(SOCKET_ERROR == AcceptSocket)
{
printf("\nSocket accept Error\n");
closesocket(SocketDescripter);
WSACleanup();
return 0;
}
lValue=0;
ioctlsocket(AcceptSocket,FIONBIO,&lValue);
char buffer[1024];
printf("i am here");
recv(AcceptSocket,buffer,sizeof(buffer),NULL);

}
}
return 0;
}

..

problems is :
its not waiting the for the client connection .. it continuously running sir.. what can i do now.. please help sir

R. Erasmus 15-Jul-11 4:03am

wild guess... remove the while(1) maybe? Increase the timeout.

@BangIndia 15-Jul-11 5:31am

no sir.. its not working.. i tried sir..

@BangIndia 15-Jul-11 5:18am

ok.. i will do then i will post the program responce

Sergey Alexandrovich Kryukov · Answer 2 · 2011-07-15T04:17:00

Solution 3

MSDN help on this API provides a whole article explaining its usage: http://msdn.microsoft.com/en-us/library/ms740141%28v=vs.85%29.aspx[^][^]. It's hard to add anything else to it.

—SA

Posted 15-Jul-11 4:17am

Sergey Alexandrovich Kryukov