When is it safe to close CAsyncSocket?

Question

CAsyncSocket crashes my application if I delete the CAsyncSocket after a call to Connect, but before the OnConnect callback has been called. ASSERT(pSocket != NULL) fails in CAsyncSocket::DoCallBack and the application exits.

In other words, if I create a CAsyncSocket, try to connect it to a server, and then kill it before that connection either succeeds or fails, I have problems. I can avoid this particular crash by implementing OnConnect and setting a flag which indicates that the connection attempt completed. If the flag is false I know it's not safe to delete.

Are there other cases I need to check for before I delete the object? Is there a single way to check if it's safe? Or do I need to implement all of the callbacks for any operation I might initiate (OnReceive, OnSend, OnConnect ) and ensure those callbacks have been called?

Sure, but the destructor calls Close, so I'm not sure how that would be any better than simply deleting it. — morgancodes, Jan 21 '14 at 22:34
You're right. I couldn't even find any way to cancel outstanding operations. But there must be a way to cleanly do that. — usr, Jan 22 '14 at 09:39
Are the methods of the instance of the `CAsyncSocket` class called from different threads? — Sergey Vyacheslavovich Brunov, Jun 30 '15 at 23:15
Related question: [CAsyncSocket::Close Crashes](http://stackoverflow.com/q/1265308). — Sergey Vyacheslavovich Brunov, Jun 30 '15 at 23:29

score 1 · Answer 1 · answered Jun 30 '15 at 23:11

Please refer to the FIX: Assertion Failed, Line 475 of Sockcore.cpp, Microsoft Support article to perform the analysis.

Additional references:

How to Handle CAsyncSocket::OnClose Gracefully, Alan Ning.
Write a Simple HTTP-based Server Using MFC and Windows Sockets, David Cook, February 1996, Microsoft Systems Journal: MFC "dead" sockets map.

When is it safe to close CAsyncSocket?

1 Answers1

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