Using ReadDirectoryChangesW() to get information about new files in a folder

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LUN2

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LUN2 Asks: Using ReadDirectoryChangesW() to get information about new files in a folder
Good evening!

I need to get information about new files in certain directory (Windows 10, C++).

To do this (1) I call ReadDirectoryChangesW in overlapped mode and point an event to be signaled when ReadDirectoryChangesW will finish, (2) wait until event will be signalled (WaitForMultipleObjects), (3) call GetOverlappedResult to get ReadDirectoryChangesW info about new files.

All actions above are repeated in a loop.

It works well, but if I create two or more files simultaneously (copy several files and paste them in the Windows Explorer), then in the step (3) I get info about one file only.

But if I rename a file, then I correctly get from ReadDirectoryChangesW two records – about old and new file names.

Buffer (FILE_NOTIFY_INFORMATION) for ReadDirectoryChangesW likely does not overflow – I allocate 10 kb, information about new files is about 50-200 bytes (their paths and names are short enough).

If I do copy/paste 1 file, then 1 file etc, than each copying is reported normally.

It seems ReadDirectoryChangesW/GetOverlappedResult return info about 1 file only if new files appear "fast" (copy/paste several files), but how can I get info about other files ?

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