Editing PowerOpen Environment

{{short description|Open standard by AIM alliance}}
{{more citations needed|date=August 2022}}
The '''PowerOpen Environment''' ('''POE'''), created in 1991 from the [[AIM alliance]], is an [[open standard]] for running a [[Unix]]-based [[operating system]] on the [[PowerPC]] [[computer architecture]].

==History==
The [[AIM alliance]] was announced on October 2, 1991, yielding the historic first technology partnership between Apple and IBM. One of its many lofty goals was to somehow eventually merge Apple's user-friendly graphical interface and desktop applications market with IBM's highly scalable Unix server market, allowing the two companies to enter what Apple believed to be an emerging "general desktop open systems market". This was touched upon by Apple's November 1991 announcement of [[A/UX 3.0]]. The upcoming [[A/UX 4.0]] (never actually released) would target the PowerOpen Environment [[application binary interface|ABI]], merge features of [[IBM]]'s [[IBM AIX|AIX]] variant of Unix into [[A/UX]], and use the [[OSF/1]] kernel from the [[Open Software Foundation]]. A/UX 3.0 would serve as an "important migration path" to this new system, making Unix and System 7 applications compliant with PowerOpen.<ref name="InfoWorld August 1992">{{cite news |title=Apple finally gets Unix right with A/UX 3.0 |newspaper=InfoWorld |date=August 10, 1992 |first=Don |last=Crabb |url=https://books.google.com/books?id=ElEEAAAAMBAJ&pg=PA68 |pages=68–69}}</ref> A/UX 4.0 and AIX were intended to run on a variety of IBM's [[IBM POWER instruction set architecture|POWER]] and PowerPC hardware, and on Apple's [[PowerPC]] based hardware.<ref name="InfoWorld Nov 1991">{{cite news |first=Cate |last=Corcoran |date=November 4, 1991 |title=Apple reveals plans for updated A/UX, PowerOpen Unix development alliance |newspaper=InfoWorld |url=https://books.google.com/books?id=Xz0EAAAAMBAJ&pg=PA1 |pages=1, 115–116}}</ref>

{{blockquote | text=PowerOpen will be the operating system for PowerPC Mac owners who need to run Unix-based applications. ... 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'' in 1993<ref name="MacWeek Vol7 Num12">{{ cite magazine | magazine=[[MacWEEK]] | title=Forces Gather for PowerPC Roundtable | volume=7 | issue=12 | date=22 March 1993 | url=https://archive.org/details/MacWEEKVol07Num12/page/n37/mode/1up | access-date=6 May 2024 }}</ref>}}

The need for the POE reduced due to the increasing availability of [[Unix-like]] operating systems on PowerPC, such as [[Linux]] [[Linux distribution|distributions]] and AIX. The [[PowerOpen Association]] was formed to promote the POE and test for conformance, and disbanded in 1995. That year, other AIM elements disbanded.

==Overview==
The POE contains [[application programming interface|API]] and [[application binary interface|ABI]] specifications.<ref name="ppc">{{cite journal | journal=IEEE | publisher=[[IEEE]] | title=PowerPC Processors | pages=550–556 | first1=Anthony | last1=Marsala | first2=Basel | last2=Kanawati | url=https://www.ece.uprm.edu/~nayda/Courses/Inel4215F03/powerpc.pdf | access-date=August 19, 2022}}</ref> The presence of the ABI specification in the POE distinguishes it from other open systems such as [[POSIX]] and [[XPG4]], since it allows [[platform (computing)|platform]]-independent binary compatibility, which is otherwise typically limited to particular [[computer hardware|hardware]]. Derived from [[AIX operating system|AIX]], the POE conforms to industry open standards including POSIX, XPG4, and [[Motif (software)|Motif]].

The POE is hardware [[computer bus|bus]] independent. System implementations can range from [[laptop computer]]s to [[supercomputer]]s. It requires a multi-[[user (computing)|user]], [[computer multitasking|multitasking]] operating system. It provides [[computer network|networking]] support, an [[X Window System]] extension, a [[Mac (computer)|Macintosh]] Application Services extension, and Motif.

Macintosh Application Services (MAS) was an Apple software product intended to run existing Mac applications alongside other applications in the X environment, including those written for the 680x0 architecture.<ref name="macweek19930322_market">{{ cite magazine | url=https://archive.org/details/MacWEEKVol07Num12/page/n36/mode/1up | title=Apple not the only player in the PowerPC market | magazine=MacWEEK | date=22 March 1993 | access-date=6 May 2024 | last1=Norr | first1=Henry | volume=7 | issue=12 | pages=37 }}</ref> Also supporting Mac applications that had been ported to PowerPC, MAS was described as "Apple's key contribution to the PowerOpen alliance" and was demonstrated running Mac applications including a [[QuickTime]] movie on three different workstation platforms. It was an optional component in the PowerOpen architecture.<ref name="byte199308_poweropen">{{ cite magazine | url=https://archive.org/details/eu_BYTE-1993-08_OCR/page/n61/mode/2up | title=PowerOpen Gives Users Freedom of Choice | magazine=Byte | last1=Halfhill | first1=Tom R. | date=August 1993 | access-date=6 May 2024 | pages=58–59 }}</ref>

==See also==
* [[PowerPC Reference Platform]]

== References ==
{{reflist}}
* [http://www.sourceware.org/pub/binutils/ppc-docs/ppc-poweropen/ PowerOpen ABI specification]
* This article was originally based on material from the ''[[Free On-line Dictionary of Computing]]'' and is used under the [[GNU Free Documentation License|GFDL]].

[[Category:IBM software]]