> But the best for me would be that konqueror is used as the browser, with
> your lib, since I run KDE. You can detect this from the env variable
> DESKTOP_SESSION which is set to "kde".

I answer to myself :
DESKTOP_SESSION doesn't seem to be reliable, since its values are not standard 
(and often is equal to "default").
So, maybe the best bet is to check the existence of KDE_SESSION_UID or 
GNOME_SESSION_ID, to know which desktop is run, if any.

By the way, I was looking for the equivalent of OSX's "open" and 
Windows' "start" under *nix. There is the command "xdg-open" from the 
freedesktop project, which does just that. It's already on my system, maybe 
it is already widely installed on systems that follow freedesktop guidelines.

-- 
Olivier Renaud