Re: Zeroing unused FFS blocks

["Steven M. Bellovin" <smb%cs.columbia.edu@localhost>]

On Sat, 26 Jan 2008 08:09:17 +1100
Daniel Carosone <dan%geek.com.au@localhost> wrote:

> On Fri, Jan 25, 2008 at 01:08:19PM +0000, Steven M. Bellovin wrote:
> > The easiest thing is to mount the file and copy /dev/zero to some
> > filename.  When the disk fills up, delete the file... 
> 
> What I do is rm the file as soon as it's created and dd is running;
> that way, as soon as dd gets ENOSPC and quits, the file is removed and
> the space is returned automatically.
> 
Good idea.  One more suggestion: run the dd as root, so that you can go
above the 100% mark.


                --Steve Bellovin, http://www.cs.columbia.edu/~smb