[systemd-devel] [PATCH 00/10] Device Management for systemd-logind

[Tom Gundersen]

On Tue, Aug 27, 2013 at 12:00 AM, David Herrmann <dh.herrmann at gmail.com> wrote:
> Hi
>
> On Mon, Aug 26, 2013 at 6:37 AM, Tom Gundersen <teg at jklm.no> wrote:
>> On Sun, Aug 25, 2013 at 8:46 PM, David Herrmann <dh.herrmann at gmail.com> wrote:
>>> logind itselfs takes care of revoking device access for inactive sessions
>>> (synchronized with session-switches!). It also tries to resume every device
>>> when a session is activated. But session-devices must not be used to watch
>>> session state! A compositor has to use the PropertiesChanged() signal plus the
>>> "Active" property of sessions for that! Session-devices do not replace this! On
>>> sessions with VTs, this is obviously replaced by the VT_SETMODE interface as
>>> usual.
>>
>> So essentially, all clients have to keep implementing the old
>> VT_SETMODE interface in addition to the new logind one?
>>
>> Would it be possible to ship a wrapper around VT_SETMODE and friends
>> so that new clients could only implement the logind interface, and
>> logind would deal with the VT layer internally (or rather, I suppose,
>> via some shim session daemon) when necessary?
>
> It's an orthogonal problem. And you don't need to handle it at all.
> The default for VT_SETMODE is a forced VT switch. So as long as no
> process in a session opens the VT and modifies VT_SETMODE, VT switch
> will "Just Work". And logind is notified via
> /sys/class/tty/tty0/active

Perfect. Thanks for the explanation.

Tom