SHRED for EXT3?

[Robert Nichols]

Mike McCarty wrote:
>     One issue is that if I overwrite the file, the location
> which contains the original data is *not* the place the overwrite
> is done to.

The 'shred' program overwrites the file in a manner that does not
reallocate the space.  You can also do that with 'dd' if you use
the "conv=notrunc" option.  A single overwrite is sufficient to
prevent anyone without the resources of certain three-letter
government agencies from recovering the data, so there's little
point in doing more unless you have a legal requirement to erase
the file to DoD specs.  You do want to 'sync' the filesystem to
make sure all writes have been flushed out before unlinking the
file.  The kernel might decide not to write out a dirty buffer if
the target file has already had its space released.

-- 
Bob Nichols         Yes, "NOSPAM" is really part of my email address.