[Tutor] Shredding Files?

[Alan Trautman]

Joshua,

Shredders are incredible OS and even controller (IDE or SCSI) specific. If
you have a Journaled filed system (i.e. JFS, ext2a, Others) that allows an
access for third party ports it can be relatively (for a non-beginner) to
write a system that will block overwrite specific spots on a hard drive. You
get the position and some even have a method of controlling that position to
overwrite the text. The problem is that you can't just resave a file over
the same name to shred an item. The hard drive controller or the hard drive
itself may overwrite any where it wants. You have to write low level
software that will record the physical location of the record/file. Then
using those positions write  1's and 0's a couple of times. The problem is
getting that specific location and the exact record length, locking the
drive so it doesn't try to optimize file IO, and then marking and
overwriting that sector(s) without corrupting the main file system.

I have been proven wrong many times on this list but I think this would have
to be done in C++ or assembler unless on of the journaled file systems has a
python API. The only shredder I have written was for DOS and it used
assembler because I talked directly to the hard drive controller and of
course every other process was locked out while I was doing it.

HTH
Alan



-----Original Message-----
From: Jmllr891@cs.com [mailto:Jmllr891@cs.com]
Sent: Monday, January 13, 2003 12:47 PM
To: tutor@python.org
Subject: [Tutor] Shredding Files?


I'm concerned with my personal privacy and I've been trying file shredders
left and right for a while, but none of them seem to be good enough. Another
problem is that I don't have enough money to buy professional software,
so...

I was wondering if anyone knew where I could find a file shredder written in
Python or a tutorial or resource where I could find information about
securely deleting data with (specifically) Python.

Thanks,
Joshua Miller