Permanent Eraser 2.3.3

Just read the myth of the Gutmann method - makes sense and has gone some way to putting my paranoias to bed - thanks!

Overwriting a file 35 times over is a complete waste of time. This blog post explains why:

http://vocaro.com/trevor/blog/2006/09/18/the-myth-of-the-gutmann-method/

Disk Utility can do a 35-pass erase, either when erasing an entire volume or from the "Erase Free Space" option (which, as you might guess from the name, does the whole random-rewrite stuff to all the empty space on your drive). True, the built-in OS X GUI apps don't offer a way to do 35-pass erase upon emptying the Trash, but that's quite different from saying they don't do it at all.

A further tip: the srm command-line tool uses a 35-pass erase by default (with options -m or -s for 7-pass or single-pass, respectively).

A single pass is enough, MFM encoded drives do not exist anymore and Guttman's paper has been invalid for many years.

See: http://www.nber.org/sys-admin/overwritten-data-guttman.html & http://shsc.info/DataRecovery

But I believe this is for deleting files, not the whole HDD like in Disk Utility...

Is this really necessary? I understand that if it is a document that is supposed to be kept out of reach of people, but 5 passes or 7 passes would not do good enough?

disk utility can over write 35 times, its an advanced option