Re: FileCopy overwrites the existing file

The most naive believe here is that "the old data disappears for good"
in case of overwriting the same sectors.

Why is it naive???? There is a speculation that *THEORETICALLY* it may
be possible to retrieve overwritten data with microscope, but this is
just a speculation - no one has *EVER* demonstrated that it can get
done in practice. Just to give you an idea, ovewriting data 3 times
(once with all 0s, once with all1s and once with a random sequence) is
the technique, approved by US Department of Defence for destroying *
CLASSIFIED* data.....

Anton Bassov




Grzegorz Wróbel wrote:
anton bassov wrote:
If I were writing CopyFile, I'd open the existing file for writing. That
means I'm overwriting the same sectors with new data, and the old data
disappears for good.

Well, I think you are much too optimistic....

In order to make sure that it all works the above way, you would have
to be a file system writer - as CopyFile() writer you would have no
control over these things whatsoever...

The most naive believe here is that "the old data disappears for good"
in case of overwriting the same sectors.

--
Grzegorz Wróbel
http://www.4neurons.com/
677265676F727940346E6575726F6E732E636F6D

.

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