How to refresh the file-read-cache by file data on disk? Or just flush the file-read-cache?

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Hi there,

I just looked for a solution on this question several days but didn't find one, could you please give me any suggestion? Thanks a lot!

The background of the question is:
We build a file filter driver for windows. When our security app is running, our driver DECRYPT the file data from disk and ENCRYPT the data when writing back to disk, so the file data on harddisk is always encrypted. Then, user cannot read file without running our app.
Unfortunately, windows has CACHE system. Windows cache gets the decrypted file data whenever our app is running or not. Therefore, if an user opens a file when our app is running, and if another user opens the same file again after quit our app, windows will read the file data from RAM cache instead of from the disk, so this user can read the file data although the file on disk has already been encrypted.

Therefore, I need a way to flush the windows file-read-cache when closing our application. But it looks like quite difficult to find a reasonable way.

Did anyone work on this before? Thanks!

Hanbear

Posted 10-Mar-11 5:05am

hanbear

Updated 10-Mar-11 13:06pm

v3

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Henry Minute 10-Mar-11 11:09am

Which language are you using? Please alter your tags to indicate this.

hanbear 10-Mar-11 19:08pm

Updated, thanks!

Dalek Dave 10-Mar-11 19:38pm

Nice to see people try before resorting to asking! plus 5 for effort

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Henry Minute · Answer 1 · 2011-03-10T05:13:00

Solution 1

This thread[^] has information on reading files without caching. It is in C# but uses the API so would be useable for C++ too.

Posted 10-Mar-11 5:13am

Henry Minute

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hanbear 10-Mar-11 19:17pm

Thank you, Henry!
I read that question when I was googling. But it's for reading/writing file by your own app. What I need is to flush windows cache for other applications such as notepad, word, PS...

Dalek Dave 10-Mar-11 19:39pm

Interesting link, henry.