View source for A/UX

{{short description|Computer operating system}}
{{Use mdy dates|date=October 2017}}
{{Infobox OS
| name                   = A/UX
| screenshot             = Apple Unix with Netscape.png
| caption                = A/UX 3.0.1 with Finder, CommandShell, and Netscape
| developer              = [[Apple Inc.|Apple Computer]]
| family                 = {{Flat list|
* [[Mac operating systems|Macintosh]]
* [[UNIX System V]]
}}
| source_model           = [[Closed source]]
| released               = {{Start date and age|1988|02}}<ref name="A/UX ships following lengthy delay">{{cite magazine |magazine=[[Computerworld]] |title=A/UX ships following lengthy delay |first=Julie |last=Pitta |date=February 15, 1988 |page=133|url=https://books.google.com/books?id=TFES14SaHgMC&pg=PT132| volume=XXII| issue=7}}</ref>
| latest_release_version = 3.1.1
| latest_release_date    = {{Start date and age|1995}}
| kernel_type            = [[Monolithic kernel]]
| license                = [[Proprietary software|Proprietary]]
| working_state          = Historic
| website                =
}}

'''A/UX''' is a [[Unix]]-based [[operating system]] from [[Apple Inc.|Apple Computer]] for [[Mac (computer)|Macintosh]] computers, integrated with [[System 7]]'s graphical interface and application compatibility. It is Apple's first official Unix-based operating system, launched in 1988 and discontinued in 1995 with version 3.1.1.<ref>{{cite magazine|magazine=[[InfoWorld]]|url=https://books.google.com/books?id=Cj8EAAAAMBAJ&q=%22apple%27s+first%22+infoworld+unix+%22a%2Fux%22&pg=PA31|date=March 7, 1988|title=Universities High on A/UX But Want More|first=Laurie|last=Flynn|page=31| volume=10| issue=10| access-date=June 19, 2017}}</ref> A/UX requires select [[Motorola 68000 series|68k]]-based Macintosh models with an [[Floating point unit|FPU]] and a paged [[memory management unit]] (PMMU).

Its foundation is [[UNIX System V]] Release 2.2, with features from Releases 3 and 4{{citation needed|date=February 2023}} and from [[Berkeley Software Distribution|BSD]] versions 4.2 and 4.3. It is compliant with [[POSIX]] and [[System V Interface Definition]] (SVID), and includes [[TCP/IP]] [[computer network|networking]] since version 2. Having a Unix-compatible, POSIX-compliant operating system enabled Apple to bid for large contracts to supply computers to the U.S. federal government.<ref>{{cite magazine |title=Uncle Sam Salutes the Mac |first=Mitch |last=Betts |magazine=[[Computerworld]] |date=August 8, 1988 |url=https://books.google.com/books?id=rEilRN4XgNgC&pg=PT60| volume=XXII| issue=32| page=60}}</ref><ref name="Computerworld Aug 1988" />

A/UX was described by ''[[MacUser]]'' as "the most interesting and impressive software to have come out of Apple since [[HyperCard]]" and by ''[[InfoWorld]]'' as "an open systems solution with the Macintosh at its heart".<ref name="InfoWorld August 1992" />

==Features==
A/UX has a [[graphical user interface]] (GUI) including the familiar [[Finder (software)|Finder]] windows, menus, and controls. The A/UX Finder is a customized version of the [[System 7]] Finder, adapted to run as a Unix [[Process (computing)|process]] and to interact with the underlying Unix [[file system]]s. CommandShell is a GUI for the underlying Unix [[command-line interface]]. An [[X Window System]] server (called [[MacX]]) with a terminal program can interface with the system and run X applications alongside Finder. Alternatively, a fullscreen X11R4 session can run without Finder.<ref name="InfoWorld August 1992" />

Apple's [[compatibility layer]] allows A/UX to run applications for [[Classic Mac OS|Macintosh System]] 7.0.1, Unix, and hybrids of both. For example, a Macintosh application can call Unix system functions, or a Unix application can call [[Macintosh Toolbox]] functions (such as [[QuickDraw]]), or a [[HyperCard]] stack can be a graphical frontend for a command-line Unix application. A/UX's compatibility layer uses some existing Toolbox functions in the computer's [[Read-only memory|ROM]], and other function calls are translated into native Unix [[system call]]s; and it cooperatively multitasks all Macintosh apps in a single address space by using a token-passing system for their access to the Toolbox.<ref>{{cite magazine | title=Macintosh Hybrid Applications for A/UX | magazine=MacTech | first=John | last=Morley | url=http://www.mactech.com/articles/develop/issue_08/064-078_Morley.html | access-date=October 3, 2017}}</ref>

The Commando utility assists users with entering [[Unix commands]], resembling the one in [[Macintosh Programmer's Workshop]]. Opening a Unix [[executable]] file from Finder opens a [[dialog box]] that allows the user to choose [[Command line interface|command-line]] options for the program using standard controls such as [[radio button]]s and [[check box]]es, and display the resulting command line [[Parameter (computer science)|argument]] for the user before executing the command or program. This feature is intended to ease the [[Experience curve effects|learning curve]] for users new to Unix, and decrease the user's reliance on the [[Unix manual]]. A/UX has a utility that allows the user to reformat third-party SCSI drives in such a way that they can be used in other Macs of that era.<ref name="InfoWorld August 1992" />

A/UX requires select models<ref>{{Cite web|url=http://support.apple.com/kb/TA31173?viewlocale=en_US |title=A/UX and Compatible Macintoshes |publisher=Apple, Inc.|date=August 1994 |archive-url=https://web.archive.org/web/20200731191716/https://support.apple.com/kb/TA31173?locale=de_AT&viewlocale=en_US |archive-date=July 31, 2020}}</ref> of [[Motorola 68000 series|68k]]-based Macintoshes with a floating point unit (FPU) and a paged memory management unit (PMMU),<ref>{{Cite web |url=http://www.kernelthread.com/publications/appleoshistory/4.html |title=Many Systems for Many Apples |first=Amit |last=Singh |publisher=Kernel Thread |date=February 2004 |access-date=December 12, 2013 |archive-date=February 21, 2009 |archive-url=https://web.archive.org/web/20090221093510/http://www.kernelthread.com/publications/appleoshistory/4.html |url-status=dead}}</ref>

==History==
A/UX 1.0 was announced at the February 1988 Uniforum conference, seven months behind schedule.<ref name="A/UX ships following lengthy delay"/> It is based on [[AT&T Corporation|AT&T]]'s [[UNIX System V#SVR2|Unix System V.2.2]] with additional features from [[Berkeley Software Distribution|BSD Unix]]. Networking support includes [[TCP/IP]], [[AppleTalk]], and [[Network File System|NFS]] implementations, developed by [[UniSoft]].<ref>{{cite magazine |title=Apple brackets Unix, Ethernet |first=Patricia |last=Keefe |magazine=[[Computerworld]] |date=March 2, 1987 |url=https://books.google.com/books?id=SZ4AAehqfn0C&pg=PA94| volume=XXI| issue=9| page=94}}</ref> The base system has no GUI, with only the command line. It can run one Macintosh application at a time, using the [[System 6]] GUI interface, although it is compatible with only about 10% of the existing Macintosh software library.

It was initially aimed at existing Unix customers, universities and [[value-added reseller|VARs]].<ref name="Apple breaks into Unix market with A/UX">{{cite magazine |first1=Laurie |last1=Flynn |first2=Carole |last2=Patton |title=Apple breaks into Unix market with A/UX |magazine=[[InfoWorld]] |date=February 22, 1988 |url=https://books.google.com/books?id=Cz8EAAAAMBAJ&pg=PA31 |page=31| volume=10| issue=8}}</ref> The system was initially sold pre-installed on the [[Macintosh II]] for {{US$|8597|1988|round=-2}}, a larger monitor could be added, or a kit could upgrade an existing Mac II for a lower price.<ref name="A/UX ships following lengthy delay"/><ref name="Apple breaks into Unix market with A/UX"/> Third-party software announced with the system's first release includes the [[Ingres (database)|Ingres]] database, [[StatView]], developer tools, and various [[productivity software]] packages.<ref name="A/UX ships following lengthy delay"/><ref>{{cite magazine |first=Laurie |last=Flynn |title=Developers Eager to Display Programs Run Under A/UX |magazine=[[InfoWorld]] |date=February 22, 1988 |url=https://books.google.com/books?id=Cz8EAAAAMBAJ&pg=PA32 |page=32| volume=10| issue=8}}</ref>

A/UX 1.1 was released in 1989, and supplies the basic GUI of System 6, with Finder, Chooser, Desk Accessories, and Control Panels. It provisions Unix with the [[X Window System]] (X11R3) GUI, the Draft 12 POSIX standard, and overall improved speed comparable to a low end Sun workstation.<ref name="Computerworld Aug 1988" /><ref>{{cite magazine |first1=Scott |last1=Mace |first2=Carole |last2=Patton |title=Apple to Support X Window in A/UX |date=August 8, 1988 |url=https://books.google.com/books?id=cDoEAAAAMBAJ&pg=PA5 |magazine=[[InfoWorld]]| volume=10| issue=32 |page=5}}</ref><ref name="A/UX, Release 1.1 Supports X Window">{{cite magazine |magazine=[[InfoWorld]] |first=Martin |last=Marshall |date=January 16, 1989 |title=A/UX, Release 1.1 Supports X Window |url=https://books.google.com/books?id=rzsEAAAAMBAJ&pg=PT30 |page=31| volume=11| issue=3}}</ref> Having its first POSIX compliant platform allowed Apple to join "a growing list of industry heavyweights" to be allowed into the US federal government's burgeoning $6 billion bid market.<ref name="Computerworld Aug 1988" />

A/UX 2.0 was released in mid-1990, adding support for simultaneously windowed applications for Macintosh, Unix, and X Window upon the desktop. ''[[MacUser]]'' said that after months of lab testing, A/UX "easily meets or exceeds nearly all our expectations. [...] A/UX 2.0 is, on the whole, a superb combination of the Mac and UNIX System V 2.2 and 4.3 BSD extensions [...] A/UX is the most interesting and impressive software to have come out of Apple since [[HyperCard]]. A/UX 2.0 is not just great UNIX software - it's great Macintosh software." The review considered system performance adequate except maybe for heavy use of [[CAD]] and compilers, even on the fastest [[Macintosh IIfx]] which has less UNIX speed than the average workstation like a [[SPARCstation 1]]+.<ref>{{cite magazine | magazine=[[MacUser]] | title=The Best of Unix and the Mac: A/UX 2.0 | first1=Alexis | last1=Rosen | first2=Jeff | last2=Pittelkau | others=MacUser Labs Staff | date=January 1991 | pages=118-134 | url=https://archive.org/details/MacUser9101January1991/page/n119/mode/2up | access-date=December 31, 2024}}</ref>

In 1991, Apple's plans were influenced by the new [[AIM alliance]] with IBM, envisioning that A/UX should become the basis for drastically scaling the Macintosh system architecture and application compatibility across the computing industry, from personal to enterprise markets. Apple formed a new business division for enterprise systems, led by director Jim Groff to serve "large businesses, government, and higher education". Basing the division upon a maturing A/UX, Groff admitted that Apple was "not a major player" in the Unix market and had performed merely "quiet" marketing of the operating system, but fully intended to become a "major player" with "very broad-based marketing objectives" in 1992. Further, Apple believed the alliance with IBM would merge A/UX, [[IBM AIX|AIX]], and System 7 into one platform—thus ultimately scaling Macintosh applications from Mac desktops to huge [[IBM RS/6000]] systems.<ref name="InfoWorld Nov 1991" />

In November 1991, Apple launched A/UX 3.0, planning to synchronize the two concurrent release schedules of A/UX and System 7. At that time, the company also preannounced A/UX 4.0, expected for release in 1993 or 1994. The announcement expounded about AIM and its platform merger proposal, and about allowing AIM to enter what Apple believed to be an emerging "general desktop open systems market". A/UX 3.0 was positioned as an "important migration path" to this new system, making Unix and System 7 applications compliant with the PowerOpen specification. A/UX 4.0 was proposed to target the [[PowerOpen Environment]] [[Application binary interface|ABI]], merge AIX features into A/UX, and use the [[OSF/1]] kernel from the [[Open Software Foundation]].<ref name="InfoWorld August 1992" /> The future A/UX 4.0 and future AIX versions were intended for a variety of IBM's [[IBM POWER architecture|POWER]] and [[PowerPC]] hardware, and on Apple's PowerPC hardware.<ref name="InfoWorld Nov 1991" />

{{blockquote|text=...Apple agreed to provide IBM with the technology needed to allow standard Macintosh applications—starting with the Finder—to run under the new AIX, much as they do under A/UX today. Apple will apply the PowerOpen label to the new version of A/UX that results from the deal; IBM will do likewise with the new AIX.|source=''MacWeek''<ref>{{cite magazine | magazine=[[MacWeek]] | title=Forces Gather for PowerPC Roundtable | volume=7 | issue=12 | date=March 22, 1993 | url=https://archive.org/details/MacWEEKV07N12/page/n37/mode/2up | access-date=October 3, 2017| page=38}}</ref>}}

In April 1992, a [[Trusted Computer System Evaluation Criteria|C2-level]] secure version of A/UX was released.<ref>{{cite magazine |date=April 13, 1992 |magazine=[[Network World]] |title=Apple unveils secure A/UX for Macintosh networks |first=Caryn |last=Gillooly |url=https://books.google.com/books?id=aw8EAAAAMBAJ&pg=PA13 |page=13| volume=9| issue=15}}</ref> Coincidentally, the [[AIM alliance]] had launched the Apple/IBM partnership  [[Taligent|Taligent Inc.]] one month earlier, with the mission of bringing Apple's other next-generation operating system Pink to market as a grandly universal operating system and application framework.

Contrary to all announcements, Apple eventually canceled A/UX 4.0. In 1995, [[PowerOpen]] was discontinued and Apple withdrew from the Taligent Inc. partnership in December. In 1996, Apple discontinued its [[Copland (operating system)|Copland]] project which had spent two years in the public view, intended to become [[Mac OS 8]] and to host Taligent software. From 1996 to 1997, the company deployed a short-lived platform of [[Apple Network Server]] systems based on [[PowerPC]] and a customized AIX.<ref>{{cite web|url=http://www.floodgap.com/retrobits/ans/aix.html|title=Floodgap ANSwers: The AIX on ANS FAQ|quote=What versions of AIX does the ANS support? Only 4.1.4 (4.1.4.0 and 4.1.4.1) and 4.1.5, and then only Apple-branded versions}}</ref> Apple's serially failed operating system strategy yielded no successor to the badly aged System 7. Apple acquired [[NeXT]] in 1996 and introduced [[Mac OS X Server 1.0]] in 1999, which merged Mac OS 8 upon the Unix-based [[NeXTSTEP]] operating system.

The final release of A/UX is version 3.1.1 of 1995.<ref>{{cite web|url=https://christtrekker.users.sourceforge.net/doc/aux/faq.html|title=A/UX FAQ}}</ref> Apple had abandoned A/UX completely by 1996.{{citation needed|date=March 2015}}

{{Timeline of Macintosh operating systems}}

==Reception==
A/UX 1.0 was criticized in the April 1988 ''[[InfoWorld]]'' review for having a largely [[command line interface]] as in other Unix variants, rather than [[WIMP (computing)|graphical]] as in System 6. Its networking support was praised.<ref>{{cite magazine |magazine=[[InfoWorld]] |date=April 4, 1988 |title=A/UX: This Operating System Is Far From Being "Unix for the Rest of Us" |url=https://books.google.com/books?id=6D4EAAAAMBAJ&pg=PA43 |first=Don |last=Crabb| volume=11| issue=14| page=43}}</ref> ''[[BYTE]]'' in 1989 listed A/UX 1.1 among the "Excellence" winners of the ''BYTE'' Awards, stating that it "could make Unix the multitasking operating system of choice during the next decade" and challenge [[OS/2]].<ref>{{Cite magazine |date=January 1989 |title=The BYTE Awards |url=https://archive.org/stream/byte-magazine-1989-01/1989_01_BYTE_14-01_PC_Communications_and_Annual_Awards_and_Digitizing_Tablets/page/n371/mode/2up |magazine=BYTE |page=327| volume=14| issue=1}}</ref> Compared to contemporary workstations from other Unix vendors, however, the Macintosh hardware lacks features such as [[demand paging]]. The first two versions A/UX consequently suffered poor performance,<ref name="A/UX, Release 1.1 Supports X Window"/> and poor sales.<ref name="InfoWorld August 1992" /> Users also complained about the amount of hard drive space it uses on a standard Macintosh, though comparable to any Unix system.<ref name="Computerworld Aug 1988" />

A/UX 3.0 was praised in the August 1992 issue of ''InfoWorld'' by the same author, describing it as "an open systems solution with the Macintosh at its heart" where "Apple finally gets Unix right". He praised the GUI, single-button point-and-click installer, one year of personal tech support, the graphical help dialogs, and the user's manuals, saying that A/UX "defies the stereotype that Unix is difficult to use" and is "the easiest version of Unix to learn". Its list price of {{US$|709|1992|long=no|round=-2}} is much higher than that of "much weaker" competing PC operating systems such as System 7, [[OS/2]], [[MS-DOS]], and [[Windows 3.1]], but low compared to the then prevailing proprietary Unix licenses of more than {{US$|2000|1992|long=no|round=-2}}. The review found the system speed "acceptable but not great" even on the fastest Quadra 950, blaming not the software but the incomplete Unix optimization found in Apple's hardware. Though "a very good value", the system's price-performance ratio was judged as altogether uncompetitive against Sun's [[SPARCstation 2]]. The reviewers thought it unlikely for users "to want to buy Macs just to run A/UX" and would have awarded ''InfoWorld''{{'}}s top score if the OS was not proprietary to Macintosh hardware.<ref name="InfoWorld August 1992" />

[[Tony Bove]] of the ''Bove & Rhodes Report'' generally complained that "[f]or Unix super-users there is no compelling reason to buy Apple's Unix. For Apple, A/UX has always been a way to sell Macs, not Unix; it's a check-off item for users."<ref name="InfoWorld Nov 1991" />

===Legacy===
Vintage A/UX users had one central repository for most A/UX applications: an Internet [[Server (computing)|server]] at [[NASA]] called Jagubox. It was administered by [[Jim Jagielski]], who was also the editor of the A/UX [[FAQ]].<ref>{{Cite web |title=jagubox's A/UX Home Page |url=http://jagubox.gsfc.nasa.gov/aux/ |url-status=dead |archive-url=https://web.archive.org/web/19990508140241/http://jagubox.gsfc.nasa.gov/aux/ |archive-date=May 8, 1999 |website=jagubox's A/UX Home Page}}</ref>

==See also==
* [[Executor (software)|Executor]], a third-party reverse-engineered reimplementation of System 7 as a Unix application
* [[Macintosh Application Environment]], Apple's Mac OS application layer for third-party Unix systems
* [[List of macOS components#Classic|Classic]], a subsystem for Mac OS X
* [[macOS]], Apple's current OS, descended from the Unix-based [[NeXTSTEP]]
* [[MachTen]], Unix in the form of a Mac OS 7 application
* [[MacMach]], an academic [[Mach (kernel)|Mach]]-based Unix experiment providing System 7 as a Unix application
* [[MkLinux]], Apple-sponsored Mach microkernel-based Linux on Macintosh hardware
* [[Star Trek project]], System 7 ported as a DOS application for [[IBM PC]] clones

==References==
<references>
<ref name="Computerworld Aug 1988">{{cite magazine |first=Alan J. |last=Ryan |magazine=[[Computerworld]] |date=August 15, 1988 |url=https://books.google.com/books?id=JAhNjLho9-sC&pg=PP6 |title=Apple keen on Unix future| volume=XXII| issue=33| page=6}}</ref>
<ref name="InfoWorld Nov 1991">{{cite magazine |first=Cate |last=Corcoran |date=November 4, 1991 |title=Apple reveals plans for updated A/UX, PowerOpen Unix development alliance |magazine=[[InfoWorld]] |url=https://books.google.com/books?id=Xz0EAAAAMBAJ&pg=PA1 |pages=1, 115–116| volume=13| issue=44}}</ref>
<ref name="InfoWorld August 1992">{{cite magazine |title=Apple finally gets Unix right with A/UX 3.0 |magazine=[[InfoWorld]] |date=August 10, 1992 |first=Don |last=Crabb |url=https://books.google.com/books?id=ElEEAAAAMBAJ&pg=PA68 |pages=68–69| volume=14| issue=32}}</ref>
</references>

==External links==
* [https://www.faqs.org/faqs/aux-faq/ Official A/UX FAQ] and [http://christtrekker.users.sourceforge.net/doc/aux/faq.html Semi-official A/UX FAQ updates]
* [http://basalgangster.macgui.com/RetroMacComputing/The_Long_View/Entries/2010/9/25_A_UX.html A/UX retrospective from 2010 at The Long View]
* [http://toastytech.com/guis/aux.html A/UX overview and tour]
* [http://www.aux-penelope.com/index.htm A/UX Installation Tutorial and General Info]

{{Apple Inc. operating systems}}
{{Unix-like}}

{{Authority control}}

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[[Category:A/UX| ]]
[[Category:Apple Inc. operating systems]]
[[Category:Macintosh operating systems]]
[[Category:Discontinued operating systems]]
[[Category:Window-based operating systems]]
[[Category:1988 software]]