Yesterday, Aaron made some interesting comments on the unified configuration system that has been discussed on the xdg-list over the last few weeks. I think some of his comments are spot on, unfortunately some others seem to be of the more paranoid hallucinogenic kind. I'm not into mushrooms myself so I will concentrate on the productive parts.
Let me start by pointing out that the discussion on the xdg-list is lively and ongoing. In my view there is an overall concensus among the participants of the discussion that it would be beneficial to have a common configuration system in place on Linux, what keeps the discussion going is the question how such configuration system should look like and how to get there. If you think you have anything to contribute in this area, by all means, join the fun.
For the sake of discussion this future configuration system has been dubbed D-Conf. Aaron describes D-Conf as vapourware, which is true of course, the challenge though is to model the vapour into a shape of our liking and then put in some honest work, sweat and tears to turn vapour into reality. Not all the participants in the discussion have the same amount of experience with configuration systems so it is important to make sure that the vapour doesn't end up like some bad trip, that would be a shame because such a system, once implemented, would be unlikely to find adoption in either KDE or Gnome.
In his blog entry, Aaron characterizes D-Conf as an effort to create the One True Unix Config File Format. I think that misses the point. Although file formats have certainly been discussed, they are not terribly interesting. What is interesting, is to have a One True Unix Configuration System. One true way to access and manage configuration settings. There is already One True KDE Configuration System, it is called KConfig. It uses an enhanced .ini-style storage format and was initially designed to support multiple different storage format. Although hardly anyone bothered over the years to come up with an alternative storage format, it should still be relative straight forward to add one. There is also the One True Gnome Configuration System which is called G-Conf. It uses an XML-based storage format and was designed to support multiple different storage formats. When you have a configuration system like KConfig or G-Conf in place and have applications using it, the storage format isn't that big of a deal... when you need something else, it's easy enough to add a different storage format. The internal design of the system is important though. It would, for example, be easy to add an XML backend to KConfig, but due to the internal design of KConfig it would be impossible at the moment to let applications take full advantage of the extra flexibility offered by XML.
Aaron makes two very interesting point when he writes "people need to realize that a new configuration system should do more and be better than what's there. so actually talk to the people making these systems." The first part can't be stressed enough, it makes no sense to design a new system if it doesn't do a better job than existing systems. The second part follows from the first because without the expertise of the the people that worked on the existing systems you are bound to repeat the failures instead of the successes. Luckily both Havoc, the lead developer of G-Conf, and me, maintainer of KConfig, are subscribed to the xdg list 
Havoc has outlined here what he thinks is currently lacking
in G-Conf.
At the KConfig side I am aware of the following wishes from KDE developers:
* Change notification
* Nested groups (if only to make khotkeysrc readable for humans)
And a recurring wish from KDE users:
* LDAP storage backend (or any remote storage)
If there are other things that you miss in KConfig don't hesitate to let me know.
I think that D-Conf creates a great opportunity to work together and improve both G-Conf and KConfig. Especially because the plans for G-Conf will make G-Conf more like KConfig, and in order to implement the above wishlist for KConfig, we will need to make KConfig more like G-Conf. I think we can create D-Conf that solves the needs of both G-Conf and KConfig and at the same time establish the elusive One True Unix Configuration System
Although I think the journey to D-Conf land will be an exciting journey I realize that many people are very happy with KDE's configuration system today and it is absolutely essential to keep it that way. That means that for D-Conf to be a success KDE developers must be able to continue to use KConfig as they do today and it means that KDE users must be able to continue to use their carefully tuned configuration as they do today. I think it's possible to do that and I hope that KDE developers will join me on this journey.
Syndicate Blogs
It's Much More than Just KDE, Gnome and Standards
I don't think anyone is being paranoid - you can't push things because someone has defined them as being a standard when they don't actually make anything better. Just think. Is an all-new new config system really going to make things any better, or is it just a case of re-inventing something for the purposes of being a standard when competitors continue to move off into the distance? What will this config system do? What will it accomplish? Will it be system-wide, beyond KDE and Gnome and any desktop? Get these things nailed down. That's a number one primary reason for all the noise going on.
Freedesktop can undoubtedly be a critical part of the free Unix Desktop's (or indeed, the Unix system) future. But, in many ways (at the moment) it is no different to all of those Unix standards bodies that got too far up their own backside in the past and pretty much handed desktop domination to you-know-who. Please, try and make sure that more nails aren't put in that particular coffin. Design by committee is a really bad idea when you aren't nailing down exactly what it is you want and certain people cannot accept that their pet project will not be accepted in its entirety. The Unix world has been through this "Yes, this may be a much better way of doing things but we have a standards body which dictates all of this stuff" crap before, and this is so similar to the eighties and nineties I can't quite believe it. Please, just don't do it. Note that this isn't finger pointing at Waldo or anyone in particular, but just generally from painful things that have happened in the past.
I know Freedesktop is called Freedesktop, but the stuff being talked about actually goes beyond the desktop. Certainly, DConf as a concept would be of major interest to server oriented open source projects, and people have pointed out that the Samba people as part of version 4 are trying to tackle many configuration issues. Presumably Apache and other major projects would have the same issues and similar experience that they can share. Coming up with a config system on your own and then hoping that these projects will somehow accept it later (hint - they won't) is just getting your carts and horses mixed up.
There is a world beyond KConfig and GConf that should really be embraced. Don't just say "Come to the XDG list", but ask these projects (get on their mailing lists) what they think about a Unified Unix Config System. This really does end up implying a unified file format though (I can understand the dilemma of Freedesktop, as how do you have standards unless you can prove them through implementations?). What would these projects want from such a system and how would they use it? Everybody depends on everybody else in the open source world, and there may be some surprising and productive answers. With people like Waldo and Havoc working for such major companies, I can't believe that there aren't people that they know who they can have informal discussions with. I don't know how a unified config system will help there though, as it is possible to have things that are incompatible even when you're all using the same system!
It's extremely easy to catch the standards bug, work inside your own sphere and think quite clearly that nothing is wrong. Unix and open source software? Been there and got the T-shirt, and that's unfortunately why I (and an awful lot of others) am not using any open source software for this one particular job I'm doing right now (not my choice in this particular case, but that's the way things have gone) or widely at all in the world today.
Just be careful. I don't think anyone need lose faith in Freedesktop, but people should get physically around a table and talk rationally about what they want it to be and what stuff like DConf should accomplish. This is a classic failure that people take as a sign of the end and Doomsday when it isn't really. They just don't work out what they want, what they were thinking of to start off with and where they want to go. If you identify those things correctly and get together then you've got a chance (think of the KDE APPEAL stuff, a really good start I think).