Re: tty: add 'active' sysfs attribute to tty0 and console device

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

> > Stuff never stops changing until the machine shuts down, its undefined.
> 
> Either you don't, or you just don't want to understand what all this
> is about. :)

At what point do you think the current tty stops changing ? The only
cases I can think of are shutdown, and when your own processes locks vt
changes.

> > Except that it doesn't address things like the permissions side of things.
> >
> > NAK again
> 
> Specifics please.

/dev/tty* and sysfs nodes don't track permissions, owner with each other,
so you are providing interfaces that either expose information they
shouldn't (which screen is valuable info in some environments), or don't
expose info they should.

sysfs also lacks vhangup so you can't fix it right now either.

> > "We have an interface that doesn't quite work for our case and we think
> > that is a bug" is not the reasoning behind writing a new random one with
> > a totally disconnected permission model that doesn't work either.
> >
> > Fix the one we have.
> 
> So how do you think you'll fix it? I better don't get into your
> ioctl() business.

Start by explaining why the current interface doesn't work for you, but
in detail.