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csocketswinapiwinsockiocp

How to know if a WSASend() operation has been completed without calling GetQueuedCompletionStatus()?

When calling WSASend(), I have to pass it a WSAOVERLAPPED instance, and I cannot re-use this WSAOVERLAPPED instance until the previous WSASend() operation has been completed (i.e. when a completion packet has been placed in the completion port).

Is there a way I can know if the WSASend() operation has been completed without calling GetQueuedCompletionStatus()?

Solution

  • You can use WSAGetOverlappedResult to get the WSASend progression:

    /* size bytes to send */
WSASend(Sock, &aBuf, 1, NULL, 0, &overlap, NULL);

/* warning no test for error cases */
DWORD dummy;
DWORD sent;   
do 
{
    /* Ask for the sending progression without waiting */
    WSAGetOverlappedResult(Sock, &SendOverlapped, &sent, FALSE, &dummy);
    /* to prevent too much CPU usage */
    Sleep(15);
} while (size != sent);