From: becka@rz.uni-duesseldorf.de
  To  : ggi-develop@eskimo.com
  Date: Thu, 15 Apr 1999 00:34:24 +0200 (MEST)

Re: current state of kernel input work?

Hi !

> Will be working on this. It is a matter of convicing the kernel guys to
> have /dev/tty represent real heads and /dev/vty to represent virtual
> heads. 

Tough task :-).

> > This avoids many security issues you would have with a multi-devfile
> > setup, as the getty just needs to chown a single file just like now.

> One aprroach I had to solve that problem was to save the current device
> state (file ownership, permissions) at the time of a VT switch. Then when
> you switch back it installs the orginal permissions.

? That doesn't help. Think of "old handles". Real virtual devices and EBUSY
on multi-open are the only protections that I think are both simple and
secure.

> Working on this with the linux input development team. Know of a good way
> to create a unique device id? Maybe something to deal with /dev numbers.

Increase a counter when you instantiate a new device.

Note the term instantiate, as given the probability to have tons of similar
devices, like a bunch of keyboards on USB or such, I'd vote for having an
object<->instance type model for the drivers. I.e. _one_ driver, that 
always gets passed a "state" (which makes it an "instance") thus avoiding 
code duplication.

CU, Andy

-- 
= Andreas Beck                    |  Email :  <andreas.beck@ggi-project.org> =