svn commit: r214431 - head/bin/rm

[Bruce Cran]

On Thu, 28 Oct 2010 14:11:14 -0700
Garrett Cooper <gcooper at FreeBSD.org> wrote:

> Unfortunately it's implied superficially by the 3 pass tort; but as
> most people who understand magnetic disks know, unless you completely
> obliterate a disk, wipe over it with random data enough times,
> whatever, the content is still on the disk and retrievable via various
> methods... I agree that this advice should be placed near the flag
> itself so that people completely understand the implications of the
> feature.

I believe the only method 10-15 years ago would have been a scanning
electron microscope, but that probably isn't possible with today's
disks. Simply writing zeros once is enough to obliterate all the data
(except for any remapped sectors).

-- 
Bruce Cran