Comment # 7 on bug 979265 from Wolfgang Bauer

(In reply to Enno Nagel from comment #6)
> Under Awesome WM, 
> 
> --- ~ � krusader -c 'hallo'
> krusader: Option � c � inconnue.
> krusader: Utilisez � --help � pour obtenir la liste des options de ligne de
> commande disponibles.

That is to be expected.
'-c' is *not* a supported option, not even inside a KDE session.
Again, try "krusader -caption 'hallo'" (without the double quotes), that should
work fine, also in awesome or any other session.

The desktop file contains krusader -caption, not krusader -c, those two are
*not* the same. (--caption would work as well though)

> then
>
> xdg-open .
>
> does not open Krusader.

Yes, you already wrote that.
But what happens instead?
Again, do you get any error message? If yes what message exactly?

> Everything is fine, because the Krusader package apparently only installs a
> /usr/share/applications/kde4/krusader.desktop.

Yes.

> But now there's a module by which an applications can be attached to a file
> type, say a folder (inode), and if Krusader is chosen, then this association
> works under KDE but not, for example, under Awesome WM. Therefore, this
> module should update a kde4-mimeapps.list, but not, say
> ~/.local/share/applications/mimeapps.list.

It's this "module"'s choice whether it updates a kde4-mimeapps.list (should
actually be kde-mimeapps.list btw) or a mimeapps.list. I don't see how we
should influence that from the KDE/krusader side (the desktop file name's
prefix, e.g. kde-, does *not* indicate that it should only be used by a
specific desktop session).
And if you do set krusader as default application in awesome, it should of
course be used as default application in awesome, no? I suppose it would be
unexpected if *some* applications you set in that "module" are only respected
by a KDE desktop, while others would be used by all desktops.

What "module" is that exactly btw?

But again, the very same krusader.desktop file (with -caption as command line
parameter) *should* work outside a KDE desktop session too, it contains nothing
that's specific to a KDE desktop session.
If it doesn't work for you, something is going wrong somewhere, and we need to
find out what that is exactly.
My best guess so far would be that the expansion of %c (by xdg-open in this
case) results in an invalid command line. A wild guess: maybe removing the
double quotes around the %c would fix it too? If I understand the specs
correctly, they shouldn't be necessary.

Unfortunately I cannot really reproduce this here. xdg-open seems to just
ignore my ~/.local/share/applications/mimeapps.list (regardless whether I set
krusader or something else) when I run it outside of KDE, and always starts
nautilus... (this would also qualify as "does not open Krusader", but removing
the -caption option from krusader.desktop does not fix that... ;-) )
Haven't tried awesome though as I don't have it installed, maybe I will install
it tomorrow. xdg-open does try to find out in what desktop session it runs and
uses different methods to find the default application accordingly.

Could you please provide your actual mimeapps.list file too (for the sake of
trying to reproduce it), to rule out a mistake on my part?