*BSD News Article 22469


Return to BSD News archive

Xref: sserve comp.unix.wizards:31211 comp.unix.bsd:12760
Newsgroups: comp.unix.wizards,comp.unix.bsd
Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!elroy.jpl.nasa.gov!swrinde!cs.utexas.edu!uunet!nwnexus!jhgrud!eskimo!scs
From: scs@eskimo.com (Steve Summit)
Subject: looking for bsd ffs user-mode implementation quote
Message-ID: <CEyuAH.IzC@eskimo.com>
Organization: none, at the moment
Date: Sat, 16 Oct 1993 01:27:43 GMT
Lines: 23

I distinctly remember, back when 4.2bsd came out, reading a nice
description of the way the new filesystem had been initially
developed in user mode, thus being able to make use of user-mode
development tools and debuggers, and not having to rebuild and
reboot an entire kernel with each pass through the edit/compile/
debug cycle.  (They had used a spare disk drive and a special
write-through device driver to enable the user-mode code to talk
directly to the disk.)

I could have sworn I read this in the "Fast File System for UNIX"
paper, but I don't seem to have a copy in my archives of the
paper I read then, and the text I remember doesn't appear in any
of the copies of the paper I can now find (bsd Unix SMM,
ACM TOCS).

Does anyone remember the text I'm talking about, and can anyone
suggest where it might be?  (I'm just trying to cite it as a
reference; it was a powerful statement on the virtues of
user-mode development of code that classically belongs in,
or is on its way into, the kernel.)

					Steve Summit
					scs@eskimo.com