[PATCHv4] Add name event to xdg-output

[Simon Ser]

On April 18, 2018 9:57 AM, Jonas Ådahl <jadahl at gmail.com> wrote:
> Replying to both Pekka and Drew at the same time here:
> 
> On Mon, Apr 16, 2018 at 11:14:51AM -0400, Drew DeVault wrote:
> > On 2018-04-16  2:57 PM, Jonas Ådahl wrote:
> > > I'd still like a bit more clarification about what to expect of this
> > > string. What I'm trying to avoid is one compositor sending "eDP-1" while
> > > another sends "Built-in Display". For example, the first is suitable for
> > > command line interfaces (e.g. movie-player --fullscreen-on HDMI-2), but
> > > the second is suitable for GUI's (e.g. a widget for selecting what
> > > monitor to play a movie on). If it can be either one, I don't see its
> > > usefulness in a generic client.
> > 
> > I'm explicitly not trying to avoid that. To me it's acceptable that one
> > compositor uses "eDP-1" and another uses "Built-in Display".
> 
> I'd be more fine if the expectation was clear that the string is
> suitable for a graphical user interface and not as a keyword in a
> command line or something similar.
>
> […]
>
> Because it may result in unnecessary inconveniences and bugs. If
> "console-movie-player" starts using a "human readable description" as a command
> line argument because it's unclear what to expect from it, but
> gnome-shell provides a descriptive string that may very well change,
> that is localized etc, it's suddenly very unsuitable for how it the use
> case the "consolemovie-player" intended to use it for.
> 
> Another thing to note is that a human readable description ala "Built-in
> Display" or "Dell HD123456 24"" may not even be unique.

I agree with Jonas here. Maybe we could add two fields:

- "codename", restricted to alphanumeric + hyphens characters (to reflect the
  current informal practice to name outputs like "VGA-1"), specified to be
  unique and persistent. These could be used in configuration files.
- "description", specified to be human-readable and not necessarily unique.
  These could be used in user interfaces.