| I assume you mean Joe uses something like sudo
| so he can mount the disk..

  Joe doesn't use the shell.  The Finder will do this for him; when  
you insert a floppy in Mac OS, it gets mounted and shows up on your  
desktop.  This is the case with all media.

| So allow users to use the fancy new mount command (with certain  
limitations on
| the mountable device node of course...)

  Yes, the fancy command is what the Finder does for him.  Options  
are details, and not really interesting.  The question is what should  
the behaviour be, and what's happening underneath the covers to  
support that?  Are we mapping UID's to something meaningful?  How?   
Or is Joe a superuser for that volume?  Which volumes get treated  
this way, and how to you choose them?

	-Fred


--
       Wilfredo Sanchez, wsanchez@apple.com
Apple Computer, Inc., Core Operating Systems / BSD
          Technical Lead, Darwin Project
   1 Infinite Loop, 302-4K, Cupertino, CA 95014