为什么给 ReadFileEx() 的回调没有收到正确的 OVERLAPPED 结构？

Question

出于某种原因，我的回调OVERLAPPED在调用ReadFileEx. 什么会导致这种情况？

更新 - 示例：

#include <stdio.h>
#include <Windows.h>

void __stdcall completion_routine(
    unsigned long dwErrorCode,
    unsigned long dwNumberOfBytesTransfered,
    OVERLAPPED *lpOverlapped)
{
    printf("Overlapped = %p\n", lpOverlapped);
}

int _tmain(int argc, LPTSTR argv[])
{
    HANDLE hvolume = CreateFile(
        _T("C:\\Windows\\Notepad.exe"), FILE_READ_DATA,
        FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
        NULL, OPEN_EXISTING, 0, NULL);
    char tempbuf[512];
    OVERLAPPED tempoverlapped = { };
    printf("%p\n", &tempoverlapped);
    if (ReadFileEx(hvolume, tempbuf, sizeof(tempbuf),
                   &tempoverlapped, &completion_routine)
        && GetLastError() == ERROR_SUCCESS)
    {
        SleepEx(INFINITE, TRUE);
    }
}

Answer 1

我忘了指定FILE_FLAG_OVERLAPPED给CreateFile。