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 //This comes from a thread in the [[https://groups.google.com/d/msg/net.unix/-H9x36DMOBQ/tHDE2z7Z4qEJ|net.unix Usenet newsgroup]]//
+<code>
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1 exptools 1/6/84; site ih1ap.UUCP
+Path: utzoo!linus!decvax!harpo!ihnp4!ih1ap!pat
+From: pat@ih1ap.UUCP (Patrick A. Fargo)
+Newsgroups: net.unix
+Subject: UNIX History
+Message-ID: <270@ih1ap.UUCP>
+Date: Wed, 11-Jan-84 15:18:47 EST
+Article-I.D.: ih1ap.270
+Posted: Wed Jan 11 15:18:47 1984
+Date-Received: Fri, 13-Jan-84 04:01:20 EST
+Organization: AT&T Bell Labs, Naperville, IL
+Lines: 42
+After reading the various responses to the history of UNIX within and outside
+AT&T Bell Laboratories, I decided to provide some other details of the
+development inside the labs.  I ordered the 2nd PDP 11/70 at Indian Hill
+in 1976. I will try to give a list of important changes in perspective.
+After development of the first UNIX systems in research, Joe Maranzano
+of Murray Hill created a UNIX support group. This group would package,
+fix bugs, and enhance the research version periodically. A year after
+this new group was formed, Heiz Lacklama and Doug Bayer of Holmdel
+modified UNIX for a PDP 11/70 using the 3 memory management registers so
+that UNIX ran as a supervisor. This product, called MERT for Mult
+Environment Real-Time operating system, was eventually support by the same
+UNIX support group.
+The third major entry was UNIX/PWD. The programmers workbench contained
+programs which controlled remote job entry, and source control. These were
+developed at Piscataway N. J. In this time period, new PDP processors such
+as the PDP 11/34, and PDP 11/23 and even a PDP 11/55 were released and off-
+springs to UNIX developed for them. The PCC (Portable C Compiler) and satellite
+library for UNIX was generated and new MINI UNIX products arose. On the
+other hand, UNIX for a HONEYWELL and UNIVAC 1100 series was also started.
+Around 1978, the UNIX support group in conjunction with a computer task force
+decided to support two major releases. UNIX/TS and UNIX/RT. UNIX/TS was USG
+UNIX and PWD UNIX combined. The UNIX/RT was basically supported MERT. Columbus
+had modifyed a version of MERT extensively, and called their product
+CB UNIX. Another version of MERT formed the basis for DMERT, a Duplex operating
+system. The thrust of only two supported versions was that UNIX/RT showed
+very good promise as being the more used version and anything that could
+be done in UNIX/TS would work in UNIX/RT.
+The advent of the PDP VAX computer now created four products. UNIX/RT and
+UNIX/TS for both PDP 111/70 and VAX 780 computers. In 1979 UNIX/RT was
+announced as 1 year to freeze, with UNIX/RT VAX officially dead. The
+remaining UNIX/TS VAX was again modified by the Indian Hill computer center
+into another product called UNIX/TS Augmented. Finally, the product
+internal to AT&T Bell Labs call UNIX/TS was the only major product supported.
+I hope this little history was interesting. If you have further questions
+I will try and answer them within company constraints.
+Patrick A. Fargo
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1a 12/4/83; site rlgvax.UUCP
+Path: utzoo!linus!decvax!harpo!seismo!rlgvax!guy
+From: guy@rlgvax.UUCP (Guy Harris)
+Newsgroups: net.unix
+Subject: Re: UNIX History
+Message-ID: <1541@rlgvax.UUCP>
+Date: Wed, 11-Jan-84 17:27:53 EST
+Article-I.D.: rlgvax.1541
+Posted: Wed Jan 11 17:27:53 1984
+Date-Received: Fri, 13-Jan-84 04:22:37 EST
+References: <270@ih1ap.UUCP>
+Organization: CCI Office Systems Group, Reston, VA
+Lines: 60
+Correcting a few typos: "Heiz Lacklama" is actually Heinz Lycklama, now
+of Interactive Systems; "UNIX/PWD" is actually PWB/UNIX.
+MERT was actually a separate OS from UNIX, which had a UNIX overlay on
+top of it (so the first case of putting a UNIX-compatible interface on
+top of a different OS was Bell's own MERT!).
+	In this time period, new PDP processors such as the PDP 11/34,
+	and PDP 11/23 and even a PDP 11/55 were released and offsprings
+	to UNIX developed for them.
+The 11/55 was just an 11/45 with faster memory and a faster floating point
+unit, so the standard UNIX that ran on an 11/45 would run on the 11/55.
+The 11/34 and 11/23 would, by and large, run versions of UNIX that ran on
+the 11/40, except that they could support the floating point instructions.
+(They also had other features, like the 11/34's cache and the 11/23+'s
+-bit UNIBUS, but standard UNIX know about them.)
+	UNIX/TS was USG UNIX and PWD UNIX combined.
+And was derived from a version of UNIX that was mostly Research V7, although
+it was, I believe, slightly earlier than the released V7 (it had a V6-ish)
+terminal driver, for instance) - the original USG UNIX and PWB/UNIX were
+derived from V6 or from V6es later than the released V6 - a set of "50 changes"
+that would turn V6 into what was running at Research at the time when the
+changes were sent out was done by Ken Thompson, and there was a
+"Phototypesetter, Version 7" distribution that contained the "modern"
+nroff/troff/eqn/tbl, the "modern" C compiler with "long", "typedef", etc.,
+the "modern" linker and archiver, and the Standard I/O library.  Most of the
+"50 changes" and "Phototypesetter, Version 7" stuff was in PWB/UNIX 1.0.
+	Another version of MERT formed the basis for DMERT, a Duplex operating
+	system.
+For the 3B20-D; the D stood for Duplex and meant there were two CPUs in a
+redundant configuration.
+	In 1979 UNIX/RT was announced as 1 year to freeze, with UNIX/RT
+	VAX officially dead.
+Just out of curiosity, why was UNIX/RT canned if, as stated earlier, it was
+felt that UNIX/RT could do everything UNIX/TS could and more?
+	The remaining UNIX/TS VAX was again modified by the Indian Hill
+	computer center into another product called UNIX/TS Augmented.
+Was there also *another* UNIX/TS variant called UNIX/TS+ (plus)?
+	Finally, the product internal to AT&T Bell Labs call UNIX/TS
+	was the only major product supported.
+And was named just UNIX as of release 3.0 (release 3.0.1 was publicly
+released as System III); it incorporated stuff from TS Augmented and
+TS+.
+Was CB-UNIX based on UNIX or MERT, and how much stuff going into the
+mainstream UNIX (S3, S5) came from CB-UNIX?
+	Guy Harris
+	{seismo,ihnp4,allegra}!rlgvax!guy
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1 exptools 1/6/84; site ih1ap.UUCP
+Path: utzoo!linus!decvax!harpo!ihnp4!ih1ap!pat
+From: pat@ih1ap.UUCP (Patrick A. Fargo)
+Newsgroups: net.unix
+Subject: UNIX History
+Message-ID: <271@ih1ap.UUCP>
+Date: Thu, 12-Jan-84 08:06:26 EST
+Article-I.D.: ih1ap.271
+Posted: Thu Jan 12 08:06:26 1984
+Date-Received: Fri, 13-Jan-84 06:33:56 EST
+Organization: AT&T Bell Labs, Naperville, IL
+Lines: 23
+Thanks to Guy Harris for the corrections. In response to his other questions:
+). Why was UNIX/RT canned instead of TS? Good question! I believe
+	    because of staffing a choice had to be made. Since DMERT was RT
+	    based and would be supported, USG felt UNIX/TS had more potential
+ 	    from a computer center standpoint.
+). Was UNIX/TS+ another modified UNIX/TS?  Yes, the UNIX/TS Augmented
+	    that I spoke of was actually called UNIX/TS++. Modifications were
+	    made that were mostly hidden from the user interface.
+). What was CB-UNIX based on?  CB-UNIX was a modified MERT. The
+	    SCCS project modified extensively, the version of MERT they had.
+	    Later, they incorporated the MERT changes in UNIX/RT releases.
+	    Eventually, an agreement to take the requested CB modifications
+	    into the standard UNIX/RT product was reached and that line of
+	    modified O.S. ceased.
+Thanks again for the corrections,
+P. A. Fargo
+AT&T Bell Laboratories IH
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1 exptools 1/6/84; site ihuxf.UUCP
+Path: utzoo!linus!decvax!harpo!ihnp4!ihuxf!larry
+From: larry@ihuxf.UUCP (Larry Marek)
+Newsgroups: net.unix
+Subject: Re: UNIX History (UNIX/RT)
+Message-ID: <1701@ihuxf.UUCP>
+Date: Thu, 12-Jan-84 10:53:11 EST
+Article-I.D.: ihuxf.1701
+Posted: Thu Jan 12 10:53:11 1984
+Date-Received: Fri, 13-Jan-84 06:39:07 EST
+References: <271@ih1ap.UUCP>
+Organization: AT&T Bell Labs, Naperville, IL
+Lines: 15
+This is about as UNofficial as it can be, but from the point of a  computer
+system ``user'' UNIX/RT was a **PIG**.  It may have been great for certain
+applications, but it certainly did NOT make a good general time-sharing
+system!
+Another point is that the whole system was riddled with bugs.  I had the
+opportunity to work with some of the RT folks (on a few of the bugs) and my
+impression was that they were a small group of people that were just
+overloaded.  Apparently the "management" decision was that RT wasn't worth the
+effort to "rescue" it.
+--
+		Larry Marek
+		 ihnp4!ihuxf!larry
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1 6/24/83; site abnjh.UUCP
+Path: utzoo!linus!decvax!harpo!eagle!mhuxl!abnjh!usenet
+From: usenet@abnjh.UUCP (usenet)
+Newsgroups: net.unix
+Subject: Re: UNIX History
+Message-ID: <399@abnjh.UUCP>
+Date: Thu, 12-Jan-84 12:34:24 EST
+Article-I.D.: abnjh.399
+Posted: Thu Jan 12 12:34:24 1984
+Date-Received: Fri, 13-Jan-84 07:00:22 EST
+References: <270@ih1ap.UUCP>, <1541@rlgvax.UUCP>
+Organization: ATTIS, NJ
+Lines: 13
+The story goes that the stuff new to 5.0 (called System V when it
+was released to the outside world) was put there to satisfy
+the needs of the people at Columbus, who were using UNIX as a base for
+writing 'Operations Support Systems', ie. programs to be used by
+operating companys in non-programmer environments.  They needed things
+like shared memory and inter-process communication.  Those features
+had already been done for CB-UNIX (Whether as part of DMERT or UNIX, I
+dont know.) but were re-done but the UNIX Support Group people.
+The hope was that the Columbus people would all convert over to 5.0
+and efforts could be consolidated.  I dont know whether this hope was
+realized, I left the Labs about the time this was happening.
+ Rick Thomas
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1 exptools 1/6/84; site ih1ap.UUCP
+Path: utzoo!linus!decvax!harpo!ihnp4!ih1ap!pat
+From: pat@ih1ap.UUCP (Patrick A. Fargo)
+Newsgroups: net.unix
+Subject: UNIX History (UNIX/RT)
+Message-ID: <272@ih1ap.UUCP>
+Date: Thu, 12-Jan-84 12:52:55 EST
+Article-I.D.: ih1ap.272
+Posted: Thu Jan 12 12:52:55 1984
+Date-Received: Fri, 13-Jan-84 07:02:46 EST
+Organization: AT&T Bell Labs, Naperville, IL
+Lines: 5
+The point about the performance and reliability of UNIX/RT is well taken,
+and I agree. But remember, UNIX/RT (MERT) was in existence about 1 and a half
+years less than UNIX/TS. The bug rate was higher, and UNIX/RT performance
+was increased dramatically for a few projects at the labs. Overall apprasail
+of UNIX/RT by the developers themselves were RT before TS.
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1 exptools 1/6/84; site ih1ap.UUCP
+Path: utzoo!linus!decvax!harpo!ihnp4!ih1ap!pat
+From: pat@ih1ap.UUCP (Patrick A. Fargo)
+Newsgroups: net.unix
+Subject: UNIX History
+Message-ID: <273@ih1ap.UUCP>
+Date: Fri, 13-Jan-84 08:11:58 EST
+Article-I.D.: ih1ap.273
+Posted: Fri Jan 13 08:11:58 1984
+Date-Received: Sat, 14-Jan-84 03:17:35 EST
+Organization: AT&T Bell Labs, Naperville, IL
+Lines: 7
+A clarification about a statement I made concerning CB-UNIX.
+The SCCS project at Columbus was NOT Source Control. It was
+short for Switching Control Center System or something like that. Thanks
+to Andy for the help.
+P. A. Fargo
+BTL -IH
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10 5/3/83; site mhtsa.UUCP
+Path: utzoo!linus!philabs!seismo!harpo!eagle!mh3bs!mhtsa!jimjwf
+From: jimjwf@mhtsa.UUCP
+Newsgroups: net.unix
+Subject: Re: UNIX History
+Message-ID: <414@mhtsa.UUCP>
+Date: Fri, 13-Jan-84 20:53:49 EST
+Article-I.D.: mhtsa.414
+Posted: Fri Jan 13 20:53:49 1984
+Date-Received: Sun, 15-Jan-84 00:06:04 EST
+References: <273@ih1ap.UUCP>
+Organization: AT&T Bell Laboratories, Murray Hill, NJ
+Lines: 19
+CB UNIX was not derived from MERT but grew out of the internal
+distributions from the USG (generic 1,2 and 3) (yes thats a new set
+of numbers, not to be confused with any of the other UNIX numbering
+conventions). The USG 3 system had some of the real time things that
+CB wanted and they were incorporated into CB-UNIX. One of the reasons
+that UNIX developed quickly and MERT did not was the support/feedback
+from the CB Labs. They had some sharp people and a good exchange with
+the USG when UNIX was an infant, but grew to love their version of UNIX
+and did not swing their applications to MERT/UNIX-RT. I suspect that if
+they had, RT might have been a good product but with only a few customers
+and an over-burdened support staff RT was put on the shelf.
+Any old USGer's care to add to this.
+I hope some one is collecting all of this UNIX folklore and plans to
+print it paperback.
+Jim Farrell
+AT&T Bell Labs
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Path: utzoo!linus!decvax!harpo!seismo!...@BRL-VLD.ARPA
+From: gwyn%b...@BRL-VLD.ARPA
+Newsgroups: net.unix
+Subject: Re:  UNIX History
+Message-ID: <15460@sri-arpa.UUCP>
+Date: Fri, 13-Jan-84 21:39:34 EST
+Article-I.D.: sri-arpa.15460
+Posted: Fri Jan 13 21:39:34 1984
+Date-Received: Mon, 16-Jan-84 01:25:49 EST
+Lines: 5
+From:      Doug Gwyn (VLD/VMB) <gwyn%brl-vld@BRL-VLD.ARPA>
+The UNIX System V IPC was already present in USG UNIX 4.1.
+(Not related to 4.1BSD.)
+It appears to me that these features must have been in UNIX/RT.
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Path: utzoo!linus!decvax!harpo!seismo!...@BRL-VLD.ARPA
+From: gwyn%b...@BRL-VLD.ARPA
+Newsgroups: net.unix
+Subject: Re:  UNIX History
+Message-ID: <15461@sri-arpa.UUCP>
+Date: Fri, 13-Jan-84 22:01:43 EST
+Article-I.D.: sri-arpa.15461
+Posted: Fri Jan 13 22:01:43 1984
+Date-Received: Mon, 16-Jan-84 01:26:04 EST
+Lines: 33
+From: Doug Gwyn (VLD/VMB) <gwyn%brl-vld@BRL-VLD.ARPA>
+Guy Harris has given much more accurate UNIX history notes than most
+of what has filtered into the ARPAnet on this topic.  I would like to
+add a couple of comments:
+It was fairly easy to take the 6th Edition UNIX 11/45 floating-point
+processor (FP11) support and add it into the 11/40 version for a
+PDP-11/34.  One subtle problem with using the 11/40 kernel on an 11/34
+is that the faulted-instruction restart code was not entirely correct
+for the 11/34, although later the 11/23 was again 11/40-compatible in
+this regard.  The 6th Edition UNIX floating-point support also had
+some bugs that needed to be fixed if one was going to make heavy use
+of floating-point on an 11/34 or 11/23, as we did at Geotronics Corp.
+The most important Columbus product to appear in USG UNIX would
+probably be the augmented "make", which is much nicer than the
+th Edition UNIX version, although still not perfect.
+All it takes to make UNIX quite usable for real-time data acquisition
+is:
+	(1) plock(2) or equivalent to ensure that user-mode code is
+	    memory-resident when needed.
+	(2) strict priority scheduling, which can be as simple as
+	    adding a privileged "real-time process queue" to the
+	    existing scheduler.
+	(3) data acquisition device driver and user-mode dual-buffered
+	    program that cooperate nicely.
+One of the past USENIX tapes contained Geotronics contributions for
+items (1) and (2) for 6th Edition UNIX.  John Quarterman, now with the
+University of Texas Dept. of CS, did a really nice job of making (3)
+work for the proprietary 11/23-based system used in the field by
+Geotronics Corp.
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1a 12/4/83; site rlgvax.UUCP
+Path: utzoo!linus!decvax!harpo!seismo!rlgvax!guy
+From: guy@rlgvax.UUCP (Guy Harris)
+Newsgroups: net.unix
+Subject: Re:  UNIX History
+Message-ID: <1551@rlgvax.UUCP>
+Date: Sun, 15-Jan-84 13:57:00 EST
+Article-I.D.: rlgvax.1551
+Posted: Sun Jan 15 13:57:00 1984
+Date-Received: Mon, 16-Jan-84 01:35:03 EST
+References: <15460@sri-arpa.UUCP>
+Organization: CCI Office Systems Group, Reston, VA
+Lines: 76
+	The UNIX System V IPC was already present in USG UNIX 4.1.
+	(Not related to 4.1BSD.)
+For you real UNIX trivia freaks, the USG 4.0 IPC was different
+from the USG 4.1 IPC.  The original message send/receive system calls sent
+to a process ID; they were changed to send to message queues, which had a
+-bit unique ID, instead (which makes more sense, as it permits you to
+transparently replace servers).  (It might be interesting to see how many
+changes to the Berkeley IPC mechanism would be needed to provide yet another
+domain which provides compatibility with the S5 IPC mechanism; obviously,
+the socket addresses would be the unique IDs.  The trick is that the S5
+messages have a "long" which is a "message type", and the S5 "msgrcv"
+call can ask to be delivered only messages of a certain type, or messages with
+a certain type number or lower number.  Also, message queues (and other
+"IPC objects") have an owner UID, owner GID, and permission bit set
+associated with them.)  The semaphore code was also very different (it may
+have been descended from semaphore code done for the pre-UNIX/TS USG systems),
+and the shared memory code was the MAUS code which used a dedicated part
+of physical memory for the shared space.  The history of Bell UNIX IPC
+mechanisms looks rather multi-branched; anybody out there with the full
+story?
+It's also interesting to see mention of various such branches in the BSTJ
+issue on UNIX (the July-August 1978 issue, Vol. 57, No. 6, Part 2).  They
+make casual reference to "the UNIX interprocess message facility", "the
+semaphore capability of the UNIX system", and to "run levels" in "the standard
+UNIX 'init' program" in the article on the Network Operations Control System,
+and also describe the MAUS shared-memory facility which was originally done
+for that system.  (Another aside: the MAUS was credited to Dale DeJager
+and R. J. Perdue; I remember seeing some code from Gould which was part of
+their driver and support code for their 5000 series electrostatic printer-
+plotter for DEC systems which was also credited to R. J. Perdue - was this
+the same guy?)  A lot of those features probably came out of Columbus but
+never made it into the UNIXes released to the outside world until System III
+(the 'init') or System V (the messages and semaphores).  Andy Tannenbaum sent
+me a "man" page for an "init" from a pre-UNIX/TS USG system which also had
+the run levels, and Hal Pierson (ex-Labs, now working here) mentioned that
+they had done both a semaphore system and the run-level based 'init' for a
+system they did which collected output from the console terminal ports of
+Electronic Switching Systems processors and allowed "craftsmen" (which I
+think is AT&Tese for "field engineer") to peruse that output for maintenance
+purposes.  They also realized that these craftsmen wouldn't know an inode if
+it came up and bit them in the *ss, so they had to replace "icheck" and "dcheck"
+with a new program which would do most of the dirty work of file system repair
+for them - Hal wrote one called "fcheck", which cleaned V6 file systems, and
+which appeared in source-code form on the PWB/UNIX 1.0 distribution tape.
+Unfortunately, PWB/UNIX 1.0 modified the V6 file system so that it didn't
+support "huge" files, and the eighth indirect pointer pointed directly to
+a block as the other seven did, so the "fcheck" there wouldn't fix a vanilla
+PWB/UNIX file system, but it worked just fine on a vanilla V6 FS.  When I
+discovered it, quite by accident, I looked at it and it sure looked like
+a super-duper file system fixer; once we got it up, we never went back to
+"icheck" and "dcheck" again.  Later on, of course, Ted Kowalski rewrote it
+to work on a V7 filesystem, added some extra checks, gave it the ability
+to reconnect files with no directory entries, put comments into the
+code (something Hal still has trouble doing :-)), cleaned it up some, and
+renamed it "fsck".
+	It appears to me that these features must have been in UNIX/RT.
+MERT had its own set of new features, including yet *another* message facility
+which didn't look like any of the "Ken&Dennis-derived" UNIX systems'
+facilities, but I don't know what they did in UNIX/RT.
+A lot of source material is in the BSTJ UNIX article, and may appear in some
+issues of Bell Labs' "UNIX Systems Newsletter" which was distributed to
+UNIX sites within AT&T & operating companies.
+Anybody for a "net.unix.history" newsgroup - at the end of the year, maybe
+we gather up all the articles, give them to some editor (maybe Dennis, who
+certainly doesn't have anything more important to do :-)) who can cull out
+the chaff, and publish it somewhere?
+	Guy Harris
+	{seismo,ihnp4,allegra}!rlgvax!guy
+Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
+Posting-Version: version B 2.10.1 6/24/83; site lzmi.UUCP
+Path: utzoo!linus!security!genrad!grkermit!masscomp!clyde!floyd!harpo!eagle!mhuxl!houxm!hogpc!pegasus!lzmi!dale
+From: dale@lzmi.UUCP
+Newsgroups: net.unix
+Subject: Re: UNIX History
+Message-ID: <166@lzmi.UUCP>
+Date: Mon, 16-Jan-84 20:20:17 EST
+Article-I.D.: lzmi.166
+Posted: Mon Jan 16 20:20:17 1984
+Date-Received: Fri, 27-Jan-84 06:24:39 EST
+References: <270@ih1ap.UUCP>
+Organization: AT&T Information Systems, Lincroft, NJ
+Lines: 42
+A correction to the comment on the source of CB-UNIX.
+I was the supervisor of the group in Columbus for a number of years that was
+responsible for the development of CB-UNIX.  The system was derived
+from the UNIX operating system that was used in the SCCS (Switching
+Control Center System), which incidentally was the first application
+of UNIX outside of research. (UNIX was running on an 11/20, at the time,
+without memory management and we deployed the first version of SCCS
+in New Jersey Bell in New Brunswick, NJ.)
+The SCCS version of UNIX had a number of unique features for the times:
+semaphores and line disciplines (in 1974!) for example. Hal Pearson
+was responsible for semaphores, and Bill Snider for line disciplines.
+Messages and shared memory were first added to CB-UNIX in about 1975 or
+. Shared memory was called MAUS (pronounced moss, standing for
+Multiple Access User Space) and was derived from an earlier version
+done by R. J. Purdue.  CB-UNIX became rather widely accepted within BTL
+as a base for turnkey Operations Systems--many of which have been
+described in the BSTJ. Note that CB-UNIX was not a derivative of UNIX/RT, but
+of Version 6 and Version 7.  PWB UNIX was also a derivative of Version 7.
+USG UNIX was originally a derivative of Version 6 and 7 with some CB-UNIX
+facilities added.  Eventaully a decision was made to consoldate to two
+versions of UNIX:  UNIX/TS and UNIX/RT. RT was a derivative of MERT, and
+TS a derivative of PWB UNIX. RT was to be used by Operations Systems, but
+was never too widely accepted. Eventually, UNIX/TS was augmented to have
+many of the features present in CB-UNIX (this was done by Roger Faulkner
+at Indian Hill, BTL. This, in turn, became the base for UNIX 4.0, which
+was never released externally. While this augmentation was going on, UNIX/TS
+was being changed into UNIX 3.0 which was release externally as SYSTEM III.
+In more recent history, CB-UNIX has been eliminated entirely in favor of
+UNIX 5.0. (one reason is because it never ran on anything other than the 11/70)
+I once had a viewgraph with all this on it which I had great fun trying to
+explain.
+Now for trivia: How many know where in UNIX lore you would find the following
+quote:  "Values of beta will result in dom!"
+			Dale DeJager
+			AT&T Information Systems
+			Lincroft, N.J.
+</code>