Re: [Xpert]Re: User-level Tasks in Hotplug Scripts?

[<Oliver Neukum lrz uni-muenchen de>]

On Tue, 5 Feb 2002, Christer Palm wrote:

> Oliver Neukum wrote:
>
> >>And what would the problem be with using an event distribution mechanism
> >>that would require the listener to have certain privileges?
> >>
> >
> > You may not want to base the distribution on privileges but on identity. eg
> > you want to associate some ports with some keyboards.
> > But in principle such a scheme should work.
> >
>
>
> Not only in principle, but also in practice, as I stated earlier. I
> would suggest having a look at "man pam_console", which is the way this
> kind of stuff is currently implemented.
>
> There is no concept of more than one "local", i.e. console, user in
> Linux (or any other OS that I know of, for that matter), and changing
> that would be quite some work. Except for obscure vintage machines, does
> computers with more than one direct-attached keyboard even exist??

Support for more than one local user is a cornerstone of X and supported
in the kernel as well. In fact the X people are reportedly proud that
they've made it work.
Linux does support several graphics adapters, X supports the
machine:console.monitor notation and you can hook up dozens of
USB keyboards let alone terminals.

One local user is the typical case, but others must in principle work.

> Anyway, in Linux, PAM is usually what (automatically) provides the
> mapping between session and privileges. You could add your own PAM
> module to associate the necessary privileges with a user session based
> on whatever parameters you want.

You need filtering events as well. I don't want anybody to know
that I've plugged a webcam into the hub in my bedroom.

	Regards
		Oliver