This document written and maintained by Allen Garvin (

Quick Definitions:
UNIX:		Operating system whose ultimate roots are 6th & 7th editions. 
		Usually contains actual AT&T-derived code (excepting 4.4BSD).
UNIX-clone:	Operating system which very strongly resembles traditional
		UNIXes.  Usually implemented with no AT&T-derived code.
UNIX-like:	Operating system which resembles traditional unix in system
		calls and/or interface

|                           Current UNIXes                           |
Company:	Hewlett Packard
Current:	11i
Newsgroup:	comp.sys.hp.hpux
	1:  System III-based
	1.2: <1987> SVR2
	2: <1988> SVR3
	3: <1988>
	5: SVR2 Some BSD
	7: SVR3, some BSD (long filenames, symlinks, sockets, et al) [680x0]
	8: shared libs, SVR3.2 (+~80% BSD) [680x0 300/400; 700 PA-RISC]
	9: DCE, SAM, Motif [680x0 400; 700/800 PA-RISC]
	10.x: SVR4.  Journaled file system [PA-RISC]
	11: 64bit [PA-RISC; IA-64 in future?]

OS:		Solaris
Company:	Sun
Current:	8
Newsgroups:	comp.sys.sun.*, comp.unix.solaris
	1.0: Retroactive name of SunOS 4.1.2 (see below) 
	   (last release is Solaris 1.1.1 == SunOS 4.1.4)
	1.1: OpenWin 3
	2.x: SVR4, threaded kernel, SMP, kerberos, CDE; 
		compiler unbundled
	    	[SPARC; i386]
	2.0: Announced <1989>, released 
	2.1: SMP support, first x86 support  
	2.3: OpenWin 3.3 (X11R5) 
	2.5: NFSv3; Sendmail 8; POSIX threads; POSIX ACL's
	2.5.1: PPC architecture support added for this version only
	2.6: NFSv3 enhancements; Doors IPC; largefiles; X11R6
	7: 2.X numbering scheme changed to X; real 64-bit option;
		optional journaling on UFS
	8: IPv6 & IPsec; GNU tools + apache;  Semi-free at first. 
	9: <2002> New volume manager.  Improved UFS.

Company:	SGI
Current:	6.5.8
Newsgroups:	comp.sys.sgi.*
	1 & 2: BSD-based??				[Motorola 680x0?]
	3: SVR3						[MIPS]
	4: <1990> SVR3.2 with much BSD. GL. POSIX	[MIPS]
	5.x: <1993> SVR4				[MIPS]
	6.x: <1994> 64-bit.				[MIPS]

Company:	IBM
Current:	4.3.3
Newsgroup:	comp.unix.aix
Comments:	Originally SVR2, with many BSD extensions over the years.
		Rather unique among UNIXes, with assorted oddities.
	1: <1986> SVR2 [i386 (IBM PS/2)]
	2: <1987> [PC RT, a RISC-based system]
	3: <1989> Logical Volume Manager [RS/6000 PPC; S/370?]
	4.x: [RS/6000 PPC]
	5L: unreleased at present [RS/6000; IA-64]

OS:		OS/390 
Company:	IBM
Comments:	Mainframe OS that thas been UNIX-fied.  Relationship
		to AIX/ESA?

Company:	BSDi
Current:	4.1
Newsgroups:	comp.unix.bsd.bsdi*
Comments:	Originally called BSD/386.  Do not confuse with 386BSD
	1: <1992> BSD/386, based on 4.3 Net/2.  Subject of lawsuit by AT&T.
	2: <1994> 4.4-Lite merged in.
	3: <1997>
	4: <1998> Runs Linux.  SMP support.
Company:	NetBSD Project
Current:	1.4.3
Newsgroups:	comp.unix.bsd.netbsd*
	0.8: 386BSD-based [i386 only?]
	1.0: <1994> 4.4-lite based.  [i386, SPARC, MIPS, 680x0, Mac, 
			PA-RISC, VAX, et al]

OS:		FreeBSD
Company:	FreeBSD Project
Current:	4.1.1
Newsgroups:	comp.unix.bsd.freebsd*
	1: <1993> Based on 386BSD (Net/2)
	2.0: <1994> Based on 4.4-Lite [i386; alpha]
	4.0: <2000>

OS:		OpenBSD
Current:	2.7
Newsgroups:	comp.unix.bsd.openbsd*
Comments:	Offshoot of NetBSD.  Code has been heavily audited
		for buffer overflows and other possible exploits.
		"Secure by default"
	1.0: <1995>

OS:		Tru64
Company:	Compaq
Current:	5.4
Newsgroups:	comp.unix.osf, comp.unix.tru64
Comments:	Initially known as OSF/1, developed by the Open Software
		Foundation.  (HP, DEC, Apollo, IBM, Bull,
		Siemens-Nixdorf).  Based on top of the Mach kernel.
		Rather unusual mix of SVR3 & BSD (now known as System
		V Environment). After OSF disbanded, Digital changed
		the name to Digital UNIX.  Compaq acquired digital in '98.
	1: <1990> Motif, SMP support, dynamic loading, DCE.  Mach 2.5 [MIPS]
	1.1: <1992?> Mach 3.0-based kernel
	1.2: [Alpha-based]
	3.2: <1996> Renamed Digital UNIX
	4.0D: <1999> Renamed Compaq Tru64 UNIX

OS:		UnixWare
Company:	SCO (Caldera?)
Current:	7.1.1
Newsgroup:	comp.unix.unixware
Comments:	Originally produced by Univel, which was acquired by
		Novell, then sold to SCO.
	1: <1992> SVR4.0 [i386]
	1.1: <1993> Novell UnixWare
	2: <1995> SVR4.2MP
	2.1: SCO acquires UW
	[any versions between 2.1 & 7??]
	7: <1997> "Gemini" SCO Unixware (branded SVR5, some OpenServer features)

OS:		OpenServer
Company:	SCO (Caldera?)
Current:	5.0.6
Newsgroup:	comp.unix.sco*
Comments:	Originally SCO UNIX (1989), then SCO ODT (to version 3).  
		Based on SVR3.2, with most SVR4 features.

OS:		DYNIX/pts
Company:	Sequent (subsidiary of IBM)
Current:	4.x??
Newsgroup:	[none?]
Comments:	Name originally owned by SCO prior to Xenix.  Sold to
		Sequent. Pioneered SMP support under UNIX.  Originally a
		"dual universe" system based on 4.2BSD & SVR3. Now SVR4.

Company:	Data General
Current:	4.2
Newsgroup:	[none?]
Comments:	Based on SVR4, with custom SMP support.  Older systems
		were based on Motorola 88k CPUs; now high-end i386.

Company:	Cray (subsidiary of SGI)
Newsgroup:	comp.unix.cray
Comments:	First 64-bit UNIX implementation; unusual internals.
		First SMP support in commercial UNIX.  Based on SVR4.
		What is CSOS?
	1: <1985>
	6: SVR3
	7: SVR4

OS:		Reliant UNIX
Company:	Fujitsu-Siemens
Current:	5.45
Comments:	Derived from SINIX.  Popular in Europe. 

OS:		MachTen
Company:	Tenon
Newsgroup:	comp.unix.machten
Comments:	4.4BSD on mach kernel for Macintoshes (both 680x0 & PPC),
		implemented on top of MacOS.  Utilizes Mach 2.5 kernel.

Company:	Concurrent
Comments:	Derived from earlier RTU (real time unix) & Harris CX/UX
		(see below).  SVR4.2MP-based, on MIPS & PPC platforms.

|                  	 UNIX-clone systems                          |

OS:		GNU/Linux
Company:	not applicable; many companies
Current:	2.4 kernel
Newsgroup:	comp.os.linux*
Comments:	Open-source (GPL) Unix clone, POSIX-compliant.  Actually
		just a kernel, the OS that people think of as "Linux" is
		usually a set of mostly GNU tools bundled together into
		"distributions" (c.g., RedHat, Slackware, Debian, et al).
	2.x: SMP support [Many platforms & architectures]
	2.4: Journal file system, LVM, rewritten virtual memory system

Company:	Free Software Foundation
Comments:	Based on Mach 3 kernel.  Work started in 1991.

OS:		Minix
Company:	Prentice-Hall
Current:	2.0.2
Newsgroup:	comp.os.minix
Comments:	Conceived as a small clone of the 7th edition of UNIX.
		Written by Andrew Tanenbaum for pedagogical purposes.
		Code is freely available, but cannot be modified and
		redistributed (patches are allowed to be distributed).
	1.0: <1987> Included in textbook "Operating Systems: Design and
		Implementation" by Tanenbaum and Woodhull
	1.5: [x86, including 8086; 680x0; SPARC]
	2.0: POSIX-compliant (fully?) [x86; SPARC]

OS:		LynxOS
Company:	Lynux Works (formerly Lynx Real Time Systems)
Current:	4.0
Newsgroup:	comp.os.lynx
Comments:	POSIX-compliant real time UNIX-clone (no AT&T-based code).

Company:	QNX (formerly Quantum Software)
Current:	4.21 ?
Newsgroup:	comp.os.qnx
Comments:	Real-time unix-like OS for [x86] systems
	1:	<1981> First microkernel OS for PC
	3:	<1990?> POSIX.1 certified kernel [i386]
	4:	most of POSIX.1b

|                  Older UNIXes, dead and/or obsolete                |

Company:	AT&T
Last release:	System V Release 4.2
Comments:	The original UNIX of all UNIXes.  Originally part of
	Bell labs, became commercial product with divestiture of AT&T.
	Ownership transferred to UNIX Systems Laboratories around 1990,
	which was purchased by Novell around 1993.  See UnixWare for
	subsequent details.
	First 7 versions are named after their printed manuals.  Later
	in-house versions at Bell Labs continued the same naming scheme
	(through the 10th edition in late 80s).  
	(work began in 1989 on PDP-8)
	1st edition: <1971> fork(2), sh, ed, roff [PDP-11]
	2nd edition: <1972> pipes
	3rd edition: <1973>
	4th edition: <1973> rewritten in C
	5th edition: <1974>
	6th edition: <1975> Released outside of Bell Labs. 
	7th edition: <1978> Online man pages, uucp, awk, adb, make
	32V: 32-bit port on Interdata.
	System III: <1982> named pipes.
	System IV: in-house version, never publicly released.
	System V: <1983> shared memory, message queues, semaphores
	System V Release 2: <1985?> opendir, readdir
	System V Release 3: <1987> STREAMS, RFS
	System V Release 3.2: <1988?> SCO collaboration
	System V Release 4: <1989> Lots from BSD & SunOS (sockets, UFS, NFS, 
		etc), shadow passwords (in optional security addon)
	System V Release 4 MP: <1992> SMP support
	System V Release 4.2: <1993?> Dynamic libraries?

Company:	Unix Systems Computer Group at University of California,
Last release:	4.4
Newsgroup:	comp.unix.bsd
Comments:	See FreeBSD, BSD/OS, OpenBSD, NetBSD for modern
	1: <1977> Tape of utilities for Version 6 (ex, csh, trek, et al)
	2: <1978> More utilities (csh & job control, et al).  Sold for $60.
	    2.8:  <1981> full OS for PDP-11, with parts of 3 & 4BSD
	    2.11: <1992 thru 1999>.  Contains much of 4.4BSD [PDP-11 only]
	3: <1979> paging virtual memory system.  First complete OS
		released by Berkeley. [VAX]
	4: <1980> reliable signals. FFS (Fast File System), 
		delivermail (== sendmail)
	4.1: <1981>
	4.2: <1983> socket support
	4.3: <1986>
	4.3-Tahoe: <1988> Version for extinct Harris Tahoe minicomputer; 
		last "true" BSD (or even Unix) in some eyes.
	4.3-Reno: <1990> POSIX-ified
	4.3 Net/2 (4.3 Lite): <1991> Subject of lawsuit by AT&T, Novell
	4.4: <1993> Last release from CSRG at UCB.  Immutable files, more 
			passwd fields, SV IPC.

OS:		SunOS
Company:	Sun
Last release:	4.1.4
Newsgroups:	comp.sys.sun.*
Comments:	SunOS is used here to refer to the BSD-based operating
		system prior to the SVR4-based Solaris
	1: <1982> 4.1BSD-based [680x0]
	2: <1985> 4.2BSD-based; NFS 
	3: <1985> 4.2 & 4.3BSD; NeWS; FIFOs; SV IPC
	4: <1989> 4.3BSD with many SV extensions (STREAMS, etc).  POSIX.
		also sold as "Solaris 1" (Solaris 1.0 == SunOS 4.1.2)
		[680x0; SPARC; i386].
	5: (See Solaris above; Solaris still uses the SunOS designation

OS:		Xenix
Company:	SCO
Last release:	System V
Newsgroup:	comp.unix.xenix*
Comments:	First UNIX for intel 8086, from Microsoft; Microsoft sold
		Xenix to SCO.  Many proprietary extensions in early days.
		Several features found their way into SVR4.
	3: <1983> [x86 only]
	5: <1987> First 32-bit UNIX for x86 platform (386).
	SV: <1988?> mostly SVR3

OS:		386BSD
Company:	Not applicable; work of Bill & Lynne Jolitz
Last release:	1.0
Newsgroup:	comp.unix.bsd.386bsd.misc
Comments:	Based on Net/2 release of BSD.  Partially MACH-based,
		with threads.  See assorted Dr Dobbs, 1992.  Very
		important historically to modern BSD development.
	1.0: <1994>

Company:	NeXT (owned by Apple)
Last release: 	4.0
Comments:	4.3BSD on top of MACH microkernel, with proprietary GUI
		written in ObjectiveC.  Large influence on Mac OS X.
		Based on Mach 2.0 kernel at first, later 2.5.
	1: <1988> DisplayPostscript [NeXT hardware (68040]
	2: <1990>
	3: <1992>
	3.1: [i386 support added?]
	3.3: [PA-RISC & SPARC support added]
	4.0: Released after Apple acquired NeXT [NeXT; i386; PA-RISC; SPARC]

OS:		Ultrix
Company:	DEC (now part of Compaq)
Last release:	4.5
Newsgroup:	comp.unix.ultrix
Comment:	ULTRIX-11 [PDP-11], ULTRIX-32 [VAX]
	1: <1984> 4.2BSD [PDP-11; 32V on VAX]
	2: Some SVR2 features?
	3: [VAX, PDP-11, MIPS]
	4: [VAX & MIPS; PDP-11 support dropped in 3] POSIX
	4.5: <1995>

OS:		DomainOS
Company:	Apollo
Last release:	SR10.4
Newsgroup:	comp.sys.apollo
Comment:	last version was "Dual Universe" UNIX (see also DYNIX,
		PyramidOS).  Acquired by HP around 1990.  Some
		contributions to OSF/1.  Previous version (SR9.*) was
		Domain/IX (and before that Aegis).  [680x0]

Company:	Pyramid
Last release:	2.0? (references to OSx 5.1)
Newsgroup:	comp.sys.pyramid
Comment:	Originally a "Dual Universe" UNIX (PyramidOS?) derived 
		from SVR3 and BSD.  Later versions were SVR4 on MIPS. 
		Pyramid is now owned by Siemens-Fujitsu.

OS:		Interactive UNIX (ISC UNIX)
Company:	Interactive Systems Corp (now owned by Sun)
Last release:	4.0
Comment:	Bought by Sun around 1992, who dropped support shortly
		thereafter (marketted for a while as a Solaris transition,
		before Solaris 2 released).  Originally PC/IX (System III &
		System V (rel 1)) around 1983.   Last release was based on
		SVR3.2 (SVR4 released briefly?). 
	4: TCP/IP, NFS support

OS:		Coherent
Company:	Mark Williams (out of business 1995)
Last release:	4.0
Comments:	UNIX-clone of 7th edition, with some SV IPC. Ran on 80286.
	4: <1993> TCP/IP support 

Company:	Apple
Last release:
Newsgroup:	comp.unix.aux
	2.0: SVR2 with 4.2BSD; system 6 Mac apps.
	3.0: <1992> SVR2.2 with 4.3BSD, soem SVR3/4 extensions.
		X11R4, MacX.  System 7 Mac apps.
	4.0:  ??

Company:	Bull
Last release:
Comments:	Also BOS/X and AIX for Bull's PPC... how does it relate
		to below?
	1: <1990> SVR3 with BSD extensions (FFS, select, sockets), SMP,
		X11R3 [680x0]
	2: <1991> job control, disk mirroring, C2, DCE

Company:	Harris (now Concurrent)
Last release:	7.1
Newsgroup:	comp.sys.harris
Comments:	Dual-universe SVR3 & 4.3BSD
		On Harris Night Hawks [motorola 68k & 88k].  
		Marketted by 3 designations: CX/UX, CX/SX (Secure),
			CX/RT (Real-Time).  Essentially the same
			code tree.
	6: POSIX.

OS:		RTU (Real Time UNIX)
Company:	Concurrent
Last release:	6.0?
Comments:	Well-known early real time Unix. motorola 68k-based Masscomp.
	3: BSD?
	4: SVR2 with BSD
	5: SVR3 with BSD (dual-universe)
OS:		UTX/32S
Company:	Gould
Last release:	1.0? 
Comments:	Based on top of 4.2BSD, implemented C2 auditing; Trusted
		Computing Base which involved trusted/untrusted access
		by users to system resources.  Ran on custom hardware.

Company:	Perihelion
Comments:	Designed specifically for parallel processing.  Ran on
		INMOS (a risc processor) transputer (Atari made a few).
		Dated from around 1987.

		Based on Mach 2.0 kernel at first, later 2.5.

OS:		Cromix
Company:	Cromemco 11
Comments:	Originally running on a [Z-80] (from the company that
		produced the first Z-80-based computer), this was the
		first UNIX-like OS on a microcomputer.	Did not contain
		UNIX code?  Later on [680x0]

Company:	Stratus
Last release:	3?
Comments:	Fault Tolerant Unix. [680x0, i860, i960]

Company:	Sony
Last release:	6
Comments:	SVR4.2-based.  Early versions on [680x0], after <1991> on [MIPS]
		Popular in Japan.  Sony ceased production in <1998>
	1: <1987>
	5: ELF

OS:		Texas Instruments System V
Company:	Texas Instruments
Last release:	3.3.2
Comments:	SVR3-based, on TI 1500 line of computers [680x0].
		SMP-support from start.  Featured bsh ("business shell"),
		a custom shell.  Sold to HP in <1992>.
	1: <1986> [68020]

Company:	NCR
Last release:	3.02
Comments:	Launched in 1982 on [680x0] hardware.  Continued on motorola
		through SVR3, switching to [i386] around the time they were
		bought out by AT&T <1991>.  Spun off from AT&T in 1995.
	3: SVR4 MP

OS:		UXP/DS (formerly DRS/NX)
Company:	Fujitsu (formerly ICL)
Last release:	7.7
Comments:	Later versions (SVR4.2) on [SPARC]
	3.2: SVR3.2

OS:		Eurix
Company:	GmbH
Last release:	2
Comments:	German UNIX.  Company also produced Munix in early <1980's>
	1: <1989?> SVR3.2. German release only [i386]
	2: <1991> SVR4, multi-lingual support

OS:		Munix
Company:	GmbH
Last release:	SVR2
Comments:	German UNIX, originally based on Version 7, first released 
		in <1982> for QU68000 [68000] & DEC PDP-11.  Later versions
		ran on 680x0 and implemented Munix/Net, a networking alternative
		to DECnet & TCP/IP, popular in Germany for a while.  See
		Eurix above.

|                           Other UNIXes                             |

                Assorted System V Release 4 derivatives
AT&T		SV/386		i386		See above.
Consensys	SVR4.2
DELL		SV		i386
ESIX		SVR4		i386
Generics	SVR4.03		i386		German
Microport	SVR4		i386
Olivetti	LSX		
UHC		SVR4		i386
Unisys		SVR4		i386
Amiga   	Amiga UX SVR4 	68030

		Assorted OSF/1 derivatives
Paragon		OSF/1		i860		on Paragon Supercomputer
Hewlett-Packard	OSF/1		PA-RISC		publicly released?
Hitachi		OSF/1-MJ	HI-370
DEC		OSF/1		DECstation	1.0
DEC		OSF/Rose	DECstation	Same as above, prior to ELF.
Dascom 		AD V1.1		i386

Acorn		RiscIX					[Risc PC]
Archipel SA	VOLVIX		SVR3.2, BSD4.4
Alcyon		Regulus					RT UNIX OS on [680x0]
Altos		Altos System V	SVR3.2			[i386]
Alliant		Concentrix	4.3BSD			SMP [680x0 MP]
Amdahl		UTS 2.1.5				[Mainframe-based]
Auragen		AurOS
Ballistic Research \
  Labs		BRL UNIX	4.3BSD			<1988> [VAX]
Carnegie-Mellon	MacMach		4.3BSD on Mach 3.0	on [680x0] macs only
Charles River \
  Data Systems	UNOS 9.2				UNIX-clone real-time OS [680x0]
Chorus		MiXV		SVR3.2, SVR4		"over Chorus nucleus"
Codata		Unisis 3.1.1	V7			[68000]. Acquired by SCO 1990
Control Data	EP/IX		RISC/OS, SVR[34], BSD	POSIX [MIPS]
Convergent	CTIX 6.4.1	SVR3			previously CTOS??
Convex		ConvexOS 10.1	4.3BSD			Acquired by HP in 1994 [Convex supercomputers]
Convex		SPP-UX		HP-UX			[PA RISC]
SPP-UX - Convex    
Data General	Sphinx
Denelcor	HEP-UPX					Direct parallel execution
Diab Systems	DNIX		SV			Real-time Unix [DIAB DS90]
Emerge Systems	RTUX					Real-time UNIX [680x0]
Fortune Systems FOR:PRO		V7			 [Fortune 32:16]
Encore		Umax 5.2	BSD			[Motorola 88k]
Everex		ENIX		SV
Heurikon	UniPlus+	SV			[68010]
Hitachi		HI-UX 03	HP-UX			Sold in Japan only
Human Computing \
  Resources	RT/EMT		V7			[PDP-11]
IBM		CPIX		V7 (later SIII?)	<1982>
IBM		AOS		BSD?			<1982> [PC RT]
Interactive	IS/3		SIII			[PDP-11; VAX]
Interactive	VM/IX		SIII			[VM/360]
Introl		INOS					 [Artisan 6809]
JMI Software	C Executive				Unix-like real-time OS
Microware	OS 9					Unix-like real-time OS [680x0]
Mt Xinu		Mach386		4.3BSD-Tahoe on Mach 2.5 [DEC LSI]
Mt Xinu		more/BSD	4.3BSD-Tahoe		[VAX, HP 680x0]
Marrow Designs	Micronix
National \
  Semiconductor	Genix		4.2BSD			early 80's [NS16032, NS32032]
NEC		UX		SV			late 80's, early 90's
Norsk Data	NDIX		BSD			Norwegian?
Omega		TOS					Thoroughbred Operating System
Opus Systems	Opus 5		SVR3			[88k] coprocessor in PCs
Perq Systems	PNX 5.02	version 7 & SIII	[PERQ 680x0]
Plexus		System B?	SV
Phase 1		Oasis
Spider Systems	QNIX		SV			Runs on top of Accent (CMU Mach \
							forbearer) [PERQ 680x0]
Tektronix	TNIX V.3	SV			[Tektronix]
Tektronix	UTEK 4.0	4.2BSD			[ver 3: NS32032; ver 4: 680x0]
Sequoias Enterprise \
  Systems    	Topix 6.7				Transaction-oriented UNIX
SGS-Ates	SUNIX		SIII & BSD		[Z-8002]
Solbourne	OS/MP 4		SunOS derivative	Basically, multi-processing SunOS
SRI		Eunice					Oddball UNIX-simulator on top of VMS
Stardent	Stellix		SV with BSD?		[titan 1500/3000]
UCB		NachOS					Tiny UNIX-like instructional OS
University of \
  Canberra	Xinu					UNIX-clone [LSI; 680x0; i386; Sparc]
VenturCom Inc	Venix		SIII on PDP-11/SV on x86
Whitesmith	Idris		V7			Unix-clone.  [8086; VAX; 68000; PDP-11]
ZENY		System V/386	SVR3.2
Zilog		Zeus		V7			[Z8001]
Zenith		?		SVR3
(Tudor Hulubei)	Thix					Unix-clone (kernel from scratch)
(Frank Naumann) FREEMiNT				Unix-like OS for Atari [680x0]
(various)	UZIX		V7			Unix-clone, from scratch [Zilog MSX]
?		ACIS 3/ACIX 4	IBM PC RT		BSD-based?
?		Arix		SV
?		MipsOS		SV (prev. BSDish)
?		MMOS					Real-time UNIX

CCI		Perps
CIM Corp.	Serix
DMC		Uni-Dol
Unidos		Unidos
IBM/Interactive	VM/LX		[UNIX on 370s??]
ONYX		Onix
Unisys		SX-110		Unix or not?