Close CAsyncSocket on server side

[AnitaEugene]

Hi
After sending data using "Send(...)", I would like to close an CAsyncSocket socket. But, how do I know that complete data is sent?
If I close after "Send(...)", I get socket error.

Thanks for the help in advance
Anita Eugene

[MikeAThon]

Read "Graceful Shutdown, Linger Options, and Socket Closure" at http://msdn2.microsoft.com/en-us/library/ms738547.aspx

You should not be getting an error after calling send() and then closesocket(). Show us the code, and tell us what error you are getting (i.e, tell us the return value for the close function, and also tell us the return value for WSAGetLastError()).

Mike

[AnitaEugene]

Hi Thanks for the response. Yes. I tried ShutDown(0) and then Close().
I get error on the function below on the CAsyncSocket
-----------------------------------------------------------------------------------
void CAsyncSocket::Close()
{
if (m_hSocket != INVALID_SOCKET)
{
VERIFY(SOCKET_ERROR != closesocket(m_hSocket));
CAsyncSocket::KillSocket(m_hSocket, this);
(Error here) m_hSocket = INVALID_SOCKET;
}
}
-----------------------------------------------------------------------------------
asserting here
ASSERT(CAsyncSocket::LookupHandle(hSocket, FALSE) != NULL);

----------------------------------------------------------------------------------------
My stack
CAsyncSocket::KillSocket(unsigned int 1884, CAsyncSocket * 0x00326f0c {CClientSock}) line 482 + 34 bytes
CAsyncSocket::Close() line 235
MTProcessRequestThread(void * 0x00000000) line 380 + 17 bytes
_AfxThreadEntry(void * 0x0012f934) line 112 + 13 bytes
_threadstartex(void * 0x00422d70) line 212 + 13 bytes
KERNEL32! 7c80b683()

I tried with Shutdown(0) after send. I get a FD_CLOSE after a very long time and all good. But, the time it takes for FD_CLOSE to come is very long.


Thanks
Anita Eugene

[MikeAThon]

Is your application multi-threaded? Are you correctly Detach()'ing the socket handle in one thread when passing it in and Attach()'ing it in the other?

Mike

[AnitaEugene]

Its a HTTP server I am working on,
On receving GET request on "OnReceive", I call the thread below to send the data and thn suutdown.

AfxBeginThread(MTProcessRequestThread,(LPVOID)wParam);

Basically, its not thread based except this.

Thanks
Anita EUgene

[MikeAThon]

... Basically, its not thread based except this.

Hehe, that seems like a pretty big thread to me.

Anyway, it explains your ASSERTs. Look at this article from Joseph Newcomer's site, which explains how to Attach/Detach the socket handle between threads, so as to avoid the ASSERTs you are seeing: http://www.flounder.com/detach.htm#Sockets

If your code is based on KB192570, or by coincidence is similar to it, then you might also want to see his scathing (and correct) criticism of the code that Microsoft gives there: "A Rewrite of KB192570: An MFC Asynchronous Socket Example Done Right" at http://www.flounder.com/kb192570.htm

Mike

[AnitaEugene]

Thanks. Let me go through this articles. I know I am doing some mistake. Let me try to fix it and post the result.
Thanks
Anita Eugene