mounting file systems on arbitrary nodes

[reiher at ucla-cs.UUCP]

UNIX allows one to mount a file system essentially anywhere.  The invariable
practice I have seen is that each file system is mounted on one given file all 
of the time.  In other words, file system 12 would always be mounted on file
/xyz, never anywhere else.  In the pursuance of some research I am doing,
I have found that enforcing this kind of behavior would be very handy.  What
I need to know is whether anyone makes use of UNIX's casual attitude about
where file systems are mounted.  In particular, would either of the following
changes to standard UNIX cause problems?

	1).  File systems may only be mounted on files which have been
		specially designated as mount points.  These files would
		be treated normally for all other purposes.

	2).  Each special mount point file would be able to serve as the
		mount point for only 1 given file system, no other.  Each
		file system would have only one mount point file.

I expect that removable media file systems (such as floppies) may be handled
differently, but I would like opinions about whether these schemes are
appropriate for them, too.

Please respond via mail.  If there is sufficient interest, I will post
my results to the net.


				Thank you,
-- 

					Peter Reiher
					reiher at ucla-cs.arpa
					{...ihnp4,ucbvax,sdcrdcf}!ucla-cs!reiher