Re: Proposal: add a _NET_WM_DESKTOP_FILE

["Jasper St. Pierre" <jstpierre mecheye net>]

On Wed, Nov 11, 2015 at 11:42 PM, Martin Graesslin <mgraesslin kde org> wrote:
> On Wednesday, November 11, 2015 11:25:15 PM CET you wrote:
> > Is there a use case where the WM_CLASS would be different from the
> > desktop file name in practice?
> >
> > I'm not aware of any applications which weren't able to adapt to the
> > new WM_CLASS matching rules once told about them -- we should just
> > document it.
>
> Erm, sorry. You cannot change the meaning and expect legacy applications will
> adopt to it. That just doesn't work.
>
> And yes I tried and the first application I checked has a mismatch between
> desktop file name and WM_CLASS. I picked xterm.

The latest version of xterm ships an xterm.desktop, and the default
class is "XTerm":
https://github.com/tkztmk/xterm/blob/master/main.h#L58

Seems like it works fine to me.

> Oh and there are also windows belonging to applications which don't have a
> desktop file at all. I can think of hundreds of test applications which just
> don't install on the system in any meaningful way. What's their WM_CLASS
> supposed to be?

When they create their .desktop file, they should give it the same
name as WM_CLASS. I don't see how this is in conflict. If they're test
applications that don't require .desktop files, then I don't see how
your _NET_WM_DESKTOP_FILE proposal helps that use case either.

We already have too many different kinds of identifiers for
applications (package name, binary name, .desktop file name,
well-known DBus name, WM_CLASS). I am strongly in the interest of
moving towards one identifier.

> Sorry, I think that's just wish-full thinking to be able to update ICCCM
> section 4.1.2.5 and everybody adopting to it.

WM_CLASS is already used as an application identifier for
~/.Xresources -- that's part of the reason it was introduced. I see no
reason why we can't use that same application identifier for .desktop
files as well. GNOME has done this in practice for well over 5 years
at this point without any major issues.

> Cheers
> Martin
>
> > On Wed, Nov 11, 2015 at 11:22 PM, Martin Graesslin <mgraesslin kde org>
> wrote:
> > > On Wednesday, November 11, 2015 11:21:44 AM CET Allison Ryan Lortie wrote:
> > > > I understand that this doesn't correspond exactly to your original
> > > > intention with this addition,
> > >
> > > no it's worse: it makes the part which I wanted to fix impossible. Which
> > > would mean that:
> > > a) I scratch what I wanted to fix
> > > b) willfully break the spec
> > > c) add a KDE specific additional property to get what I wanted in the
> > > first
> > > place
> > >
> > > > but I think your original intent is
> > > > unrealisable: you will either have many apps that provide nothing at
> > > > all,
> > >
> > > which is fine! This is an optional flag. It's not a requirement. The
> > > proposal (after Thomas update) will say that the window MUST NOT specify
> > > the desktop file if it doesn't know it. If it cannot be matched to a
> > > desktop file: that's fine.
> > >
> > > > or you will have some apps that provide something other than the
> > > > desktop file name.
> > >
> > > This would be a clear violation of the spec. Adding a requirement to add
> > > DBus to it, will not fix windows ignoring the spec and passing in wrong
> > > data.>
> > > > This is the same problem as the previous attempt to solve this problem:
> > > > there was a proposal at some point that the wmclass should be equal to
> > > > the name of the desktop file.  For many apps this was true, but coverage
> > > > was never 100%.
> > >
> > > Right, because you cannot change the meaning of an existing property and
> > > then assume that it will work. Because of that I propose a new additional
> > > protocol applications can opt-in to when they can provide the
> > > information.
> > >
> > > Cheers
> > > Martin
> > > _______________________________________________
> > > wm-spec-list mailing list
> > > wm-spec-list gnome org
> > > https://mail.gnome.org/mailman/listinfo/wm-spec-list



-- 
  Jasper