Securely delete files...

[Faramir]

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Chris De Young escribió:
> Robert J. Hansen wrote:
>> Faramir wrote:
>>> lets say I just want to avoid recovery software like "get data back"
>>> being able to recover a file. Is there a reliable way to do it
>>> without going to "extreme" solutions?
>> No.
> 
> It's not clear to me why this is the case; it seems to me that if you're only
> worried about access that uses the drive's own process for getting bits off the
> platters, then a simple overwrite (and only once) would be sufficient. If you're
> going to try to read the drive using the drive's own read/write heads and
> firmware (which all of these software applications do, right?), the most
> recently written bits are the only ones that should be available.

  That's is what I am no longer sure I can do, I mean, it seems I can
tell the disk "overwrite that file", and the disk can write somewhere
else, not over the sectors containing the file I want to "destroy" (at
least, that is what I have understood from this thread). But maybe there
is some app capable of telling the disk "write this random patter right
over the place where the original file is, and not in other places".

  Or maybe if I fill the whole disk with zeroes, it MUST overwrite the
file... since I would be using the full capacity of the disk, there
would not be "other places" available... but this was already discarded,
and I didn't really understand why it is not reliable in the "avoid
commercial software utilities for info recovery" context.

> That doesn't protect you from someone who wants to take apart the drive in a
> clean room and spend lots of money reading it other ways, of course, but that
> seemed out of bounds from the original question.

   Well, the original question did not include any context (and I was
not the one making the question), so it was very reasonable to talk
about physical destruction of the drive, but since I am sure some people
is not concerned about NSA or KGB trying to recover the info, just about
low budget people, I added that context... something like "I want to be
sure my room mate won't be able to recover the picture portraying my
girlfriend naked, which I just deleted" (it is just an imaginary
context, I don't have that problem).

 Best Regards

P.S: about "Ahh, the climactic scene from the movie "Lord of the disks"
where Frodo BaGPGins drops the platters in Mount Doom.", I figure I
would have to jump to the lava to save "my precious" info XD
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