/dev/io , /dev/mem : only used by Xorg?

[Ted Mittelstaedt]

> -----Original Message-----
> From: Kris Kennaway [mailto:kris at obsecurity.org]
> Sent: Tuesday, March 01, 2005 1:29 AM
> To: Ted Mittelstaedt
> Cc: Kris Kennaway; Loren M. Lang; Rob; FreeBSD questions
> Subject: Re: /dev/io , /dev/mem : only used by Xorg?
>
>
> On Tue, Mar 01, 2005 at 12:06:11AM -0800, Ted Mittelstaedt wrote:
>
> > >> Another strange thing is that /dev/random should block when it
> > >> runs out of entropy - it doesen't seem to do so, however.  And the
> > >> device doesen't seem to gain entropy that quickly.
> > >
> > > No, it should not block because it's not defined to block
> >
> > In FreeBSD
> >
> > > and that
> > > would be a bad interface anyway.
> >
> > The "u" in /dev/urandom means unblocking.
>
> It also means "return stuff even when you have no more entropy".
> Can't get there from here.
>

Presumably the app writer knows this.

Come now, I never said it was a -good- interface.  The ideas of how
the random device should work are somewhat of a moving target among
UNIXes.  The yarrow generator is one of the better ones us ordinary
mortals
have access to, I wonder what the NSA uses?

Ted