[systemd-devel] Automatic user ACL management

Martin Pitt martin.pitt at ubuntu.com
Sun May 17 06:00:11 PDT 2015

Mikhail Morfikov [2015-05-17 12:46 +0200]:
> As you can read, for instance here
> ( http://enotty.pipebreaker.pl/2012/05/23/linux-automatic-user-acl-management/
> ), logind, which is a part of systemd, can set permissions to some
> devices for user sessions. There's also a vid showing how this kind of
> behavior works in practice
> ( https://www.youtube.com/watch?v=qcD4Qr5ldbI ). In short, if you
> start, let's say, amarok, and you play some song, you will hear the
> sound till you switch to another user or TTY where you have only the
> login prompt. That's because the active session became inactive.

If you log into the TTY, the sound will continue, as you will again be
in a foreground session, right?

> I know that you can simply add a user (or users) to a specific group,
> in this case "audio", and that will 'fix' this issue

Personally I wouldn't consider this a "fix"; it's a very wrong thing
to do for environments with multiple users. But indeed using static
group memberships will achieve this "first user to grab a device will
keep owning it" behaviour.

Martin Pitt                        | http://www.piware.de
Ubuntu Developer (www.ubuntu.com)  | Debian Developer  (www.debian.org)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: Digital signature
URL: <http://lists.freedesktop.org/archives/systemd-devel/attachments/20150517/61035433/attachment.sig>

More information about the systemd-devel mailing list