Common call for launching file browser

[Cybe R. Wizard]

Derek Broughton <derek at pointerstop.ca>  said:
> Charlie, you _know_ this is Linux - we can do anything!
> 
> As long as you can identify the desktop, it can't be that difficult
> (as xdg-open shows) to invoked the appropriate application for the
> desktop - or it could be done through the "alternatives" system.

As for xdg-open, it seems to me that it only opens a file with the
preferred application or a URL with the preferred browser.  Am I missing
something?  If it /does/ open a file manager I haven't been able to do
it.
I am not familiar with the "alternatives" system.
<googles>
hmmm...
<reads man page>
I can't find a correct group name for a file manager
in /etc/alternatives.
<checks gconf-editor>
I can't find a place to change the default file manager anywhere.  I
would love to set it to use PCManFM if I only could.

I /know/ that we, as Linux users, can do anything.  I am stumped by
the, "how?"
Even inside my own system this doesn't look so easy, much less
for /any/ system.

Help?

Cybe R. Wizard
-- 
Nice computers don't go down.
	Larry Niven, Steven Barnes
		"The Barsoom Project"