Subject: Re: 32 bit dev_t, Revision 2
To: None <tech-kern@NetBSD.ORG>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: tech-kern
Date: 01/11/1998 18:21:08
[ Note, headers trimmed :-]

On Sun, 11 Jan 1998 17:30:18 -0800 
 Paul A Vixie <paul@vix.com> wrote:

 > back on topic, can someone 'splain to me why device special files are still
 > inside a UFS/FFS container with special "MAKEDEV" scripts?  if we can do
 > /proc it seems to me that /dev can be a special file system whose entries
 > are _made_ at successful probe time, using monotonically increasing dev_t's
 > with an opaque internal structure?  ted says this has been done in some
 > form.  if we're going to pull dev_t through a knothole backward and touch
 > the kernel in 125 places to do it, why not do the Right Thing and just stop
 > trying to figure out whether 12/20 is a good split or whether MI and MD need
 > different ranges and whether one or two tables are the right approach.  we
 > KNOW this isn't the right approach, why are we taking it anyway?

Um.. probably because:

	(1) There are several problems with a "devfs" approach, including
	    non-persistence of chmod's and symlinks.

	(2) There are some programs out there that like to compare dev_t's
	    to see if e.g. file foo is on the same file system as file bar.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                            Home: +1 408 866 1912
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