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Date: Tue, 16 Nov 2010 22:42:50 +0100
From: Lennart Poettering <mzxreary@0pointer.de>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Kay Sievers <kay.sievers@vrfy.org>,
        linux-kernel <linux-kernel@vger.kernel.org>, Greg KH <greg@kroah.com>,
        Werner Fink <werner@suse.de>, Jiri Slaby <jslaby@suse.cz>
Subject: Re: tty: add 'active' sysfs attribute to tty0 and console device
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On Tue, 16.11.10 20:49, Alan Cox (alan@lxorguk.ukuu.org.uk) wrote:

> /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.

Well, I find the informatoin who is logged in much more valuable then
the information whether I am active or not. And the who is logged in
informatin I can find out with a simple stat() on the tty caller.

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

Which is a feature, no a bug. It would be kinda messy if the service
which manages device access based on whose session is active would
always be forcibly stopped from doing so if somebody calls vhangup().

Lennart

-- 
Lennart Poettering - Red Hat, Inc.