Re: what is the difference among files in /gnu/store

[Julien Lepiller <julien@lepiller.eu>]

Le Thu,  2 Jun 2022 18:24:20 +0000,
Gottfried <gottfried@posteo.de> a écrit :

> Hi Julien,
> 
> thanks for your explanation
> 
> >> How did you get this list of store items?  
> 
> I simply used "catfish" to look for "TraditionalGreen" and it gave me 
> those 4 packages.

I see. In general, it's not very useful to figure out what the exact
store path for a file is. I'm not very familiar with Mate, but I
suppose it has some sort of theme chooser? You should use it and select
your favorite theme directly.

> 
> >> The second is the content of a system generation. You probably
> >> installed mate in your system :). The system generation is also
> >> the union of packages that you declared, so it includes mate, and
> >> consequently, the theme.  
> 
> When I installed Guix, it gave me only 3 options of desktops: MATE, 
> Enlightment and Awesome. That's why I installed all three of them.
> 
> I knew only MATE, I didn't know what Enlightment and Awesome was, so
> I installed them to get to know them. There was no Gnome, XFCE, KDE
> ... available. So I was wondering why some Guixers have e.g. Gnome or
> XFCE installed.
> Now checking in the Guix Packages I found Gnome and XFCE available,
> but no KDE. KDE, AFAIK isn't available at the moment. Is that right?

Correct, KDE is a bit difficult to package, and we don't have enough
people interested in making the effort.

> 
> >> If possible, please don't use a store path in your configuration.
> >> If you update the system, the new version will be at a different
> >> location (even if the version number is the same, as you've seen
> >> with mate-themes). It might get garbage-collected and will
> >> definitely get out of date. 
> 
> I didn't do anything. It was installed this way when I installed Guix 
> System.
> In which other location Guix will install the new version?

That's the problem: I don't know, because I can't predict it. A store
path looks like this:

/gnu/store/<hash>-<name>-<version>/

The <name> and <version> parts are easy to understand. The <hash> part
is a string that is derived from the <hash> part of the dependencies of
the package. Every time the package is updated, or one of its
dependencies, or a dependency of a dependency, etc, is updated, the
<hash> part changes.

That's why you have two "mate-themes" packages in your store. They're
both at the same version, but they were built with different packages,
because at least one of their dependencies is different.

After an update, guix will create a new store path for the new item.
Guix never updates anything in place, which guarantees that if
something works one day, it will always work.

> 
> >> Instead, you should reference a theme by its name only. If mate
> >> lets you, try to set the theme to "TraditionalGreen" and that will
> >> always be the latest version.  
> 
> In my home folder there is a hidden folder with the name
> .icons and another one with the name .themes.
> I thought that in one ot those my "themes" will be stored.
> But when I looked for them, catfish found them in /gnu/store.
> Those tho folders are empty.
> So if I would be able to install new themes, I thought to install
> them there, but I don't know if Guix will find them, because as far
> as I know Guix will look in /gnu/store.

Some themes come from guix packages, such as TraditionalGreen, but you
could install custom themes (outside of guix) in your .themes folder.
Mate will look both at this folder and in the store, at a location that
Guix will provide it (which is the location that contains the
up-to-date version).

If you select a store path directly, your config will always point to
that fixed version (remember a store path is immutable, it doesn't
change even with updates). So, you won't get updates. Instead, you
should just use the name of the theme, so Mate will look for a theme by
that name, and find it in the latest store path that Guix configured
for it. After an update, Guix will configure the new path and Mate will
be able to load the new version transparently.

> 
> Gottfried
> "hacking" on the basics
> 
> 
> Am 02.06.22 um 07:12 schrieb Julien Lepiller:
> > Hi Gottfried,
> > 
> > How did you get this list of store items?
> > 
> > The first one comes from "mate". That's a meta-package that
> > contains the union of a bunch of packages that are needed to run
> > mate.
> > 
> > The second is the content of a system generation. You probably
> > installed mate in your system :). The system generation is also the
> > union of packages that you declared, so it includes mate, and
> > consequently, the theme.
> > 
> > The last two are different versions of "mate-themes". I don't know
> > which is more recent.
> > 
> > If possible, please don't use a store path in your configuration.
> > If you update the system, the new version will be at a different
> > location (even if the version number is the same, as you've seen
> > with mate-themes). It might get garbage-collected and will
> > definitely get out of date.
> > 
> > Instead, you should reference a theme by its name only. If mate
> > lets you, try to set the theme to "TraditionalGreen" and that will
> > always be the latest version.
> > 
> > HTH!
> > 
> > On June 1, 2022 9:03:39 PM GMT+02:00, Gottfried
> > <gottfried@posteo.de> wrote:  
> >> Hi guixers,
> >>
> >> e.g.
> >>
> >> I have in my MATE desktop a theme called "TraditionalGreen"
> >>
> >> There are several files.
> >> What is the difference?
> >>
> >> /gnu/store/09bi02ldaqsykdfi8szv225z4adl98hj-mate-1.24.1/share/themes/TraditionalGreen
> >>
> >> /gnu/store/65dvsqhxly3cs33m935amvg1wc38s1ii-system/profile/share/themes/TraditionalGreen
> >>
> >> /gnu/store/aqpb71z7nl1jbaxi7q2364x5hm2lsab9-mate-themes-3.22.21/share/themes/TraditionalGreen
> >>
> >> /gnu/store/y3cwrifdqvainwddij7zvk0lspvbpsia-mate-themes-3.22.21/share/themes/TraditionalGreen
> >>
> >>
> >> The 1. and 2. have a different Icon, it has something to do with a
> >> link (Verknüpfung german).
> >>
> >> Which one is used for the desktop?
> >>
> >> I want to learn the basics!
> >>
> >> Gottfried  
> >   
>