'Clean' empty hard drive space

From: Alex (alex_at_totallynerd.com)
Date: 04/27/04

Date: 27 Apr 2004 12:06:43 -0700

Hi all,

I work for a company that writes confidential data to the hard drive
daily then deletes it. I'd like to know if there's anyway to 'clean'
the free/unoccupied space on the hard drive to make undeleting files
impossible. I know there's utilities that do this by formatting,
writing random data, reformatting, and so on.. but we want the data on
the drive to stay intact... just cause deleted data to be

Any suggestions? I've written a small perl script to write random
text to a file until the HD is full... then it deletes the file, but
I'm not sure if this is truly doing anything useful.

Another option is to add a second hard drive to each computer then run
the deletion software on the drives, but most systems are
small-formfactor Dells with no area for a second HD.

Thanks for any comments or suggestions. OS is Red Hat 9.0 and
Slackware 9.1 with EXT3 file system.