Destroying files

[Erno Kuusela]

On Thu, 28 Oct 1999 21:38:09 -0400, Gordon McMillan <gmcm at hypernet.com>
wrote:

>> Yes, I'm on Windows 95. No, deleting files does not remove them
>> from your hard drive; They can be recovered by computer forensics
>> experts or by nosey hacks. I'm putting my PC up for sale, and the
>> thought is troubling.
>
>How about opening a file, writing '\000'*1024 (and flushing) 
>until it runs out of disk space, and then deleting it? A wizard 
>might be able to get filenames out of the FAT, but I don't think 
>there's be any data left.
>

writing zeros over the data does not make it unrecoverable.
there are numerous companies that specialise in this kind
of recovery.

you can find lots of discussion about this with dejanews. see
for example http://www.deja.com/=dnc/getdoc.xp?AN=375423857 or
http://www.deja.com/=dnc/getdoc.xp?AN=457401725 .

to make it short, the only sure way to prevent data
recovery is to melt the disk and this is what people that
are serious about the matter usually do...

now, the python file objects seem to be missing a melt() method...
perhaps this can be added for python 2.0? or perhaps a more suitable
name would be self_destruct(), so it would not be tied to any single
method.


  -- erno