Re: Secured RM ? (source)

I don't think this will work. When you

> if ( (Pfp = fopen(Pfilename, "wb") ) == NULL)

the file will be truncated. Subsequent writes could be anywhere on the
platter; you're building a new file.

I think you can work this way if you open the file for read/write
access, although I'd be more inclined to take the file name into the
directory and then walk the inodes.

jps
-- 
Jack P. Starrantino     (215) 674-0200 (voice)
SEMCOR, Inc.            (215) 443-0474 (fax)
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Hello jps@monad.semcor.com (Jack P. Starrantino)
  and cypherpunks@toad.com

...
> I think you can work this way if you open the file for read/write
> access, although I'd be more inclined to take the file name into the
> directory and then walk the inodes.

Yuck!

Opening the file for read/write should be ok on all filesystems
where walking the inodes is doable and ok, and will be more portable.

Walking the inodes has the advantage that it won't run out of disk space,
but I suspect confidential files with holes will be rare.

There's no automatic rm that will also delete all backups of the file.
(You are keeping backups, aren't you?)


Hope I'm making sense...

Jiri
- --
If you want an answer, please mail to <jirib@cs.monash.edu.au>.
On sweeney, I may delete without reading!
PGP 463A14D5 (but it's at home so it'll take a day or two)
PGP EF0607F9 (but it's at uni so don't rely on it too much)

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On Sun, 17 Dec 1995, Jiri Baum wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> 
> There's no automatic rm that will also delete all backups of the file.
> (You are keeping backups, aren't you?)
> 

In this particular case what im concerned about is a temporary  cleartext 
copy of a permanently encrypted document.  The cleartext only exists for 
about 1-4 seconds, and then is deleted, so backups arent really a 
problem..