Editing OpenServer (section)

==History==

===SCO UNIX/SCO Open Desktop===
In 1987 [[AT&T Corporation]], [[Microsoft]], and [[Sun Microsystems]] agreed to combine their versions of the [[Unix]] operating system. [[Santa Cruz Operation]] (SCO) sublicensed Microsoft's [[Xenix]] and wanted to retain the Xenix name, but AT&T said "If they want to call it Unix, they've got to use it the way it is. We don't want another set of variants".<ref name="patton19880118">{{Cite magazine |last=Patton |first=Carole |date=18 January 1988 |title=AT&T Unix Standard Could Impact Santa Cruz Operation 
 |url=https://books.google.com/books?id=Dz8EAAAAMBAJ&pg=PA33#v=onepage&q&f=false |access-date=2025-05-25 |magazine=[[InfoWorld]] |page=33 |volume=10 |issue=3}}</ref>

SCO UNIX was the successor to Xenix, derived from [[UNIX System V|UNIX System V Release 3.2]] with an infusion of Xenix device drivers and utilities. SCO UNIX System V/386 Release 3.2.0 was released in 1989, as the commercial successor to SCO Xenix. The base operating system did not include [[TCP/IP]] networking or [[X Window System]] graphics; these were available as optional extra-cost add-on packages. Shortly after the release of this bare OS, SCO shipped an integrated product under the name of SCO Open Desktop, or ODT. 1994 saw the release of SCO MPX, an add-on [[symmetric multiprocessing|SMP]] package.

At the same time, AT&T completed its merge of Xenix, [[BSD]], [[SunOS]], and [[UNIX System V|UNIX System V Release 3]] features into [[UNIX System V Release 4]]. SCO UNIX remained based on System V Release 3, but eventually added home-grown versions of most of the features of Release 4.

The 1992 releases of SCO UNIX 3.2v4.0 and Open Desktop 2.0 added support for long [[file name]]s and [[symbolic link]]s. The next major version, OpenServer Release 5.0.0, released in 1995, added support for [[Executable and Linkable Format|ELF]] executables and dynamically linked [[shared object]]s, and made many kernel structures dynamic.

===SCO OpenServer===
SCO OpenServer 5, released in 1995, would become SCO's primary product and serve as the basis for products like PizzaNet (the first Internet-based food delivery system done in partnership with [[Pizza Hut]]) and SCO Global Access, an Internet gateway server based on Open Desktop Lite.<ref>{{cite news |first=Christine |last=Burns |title=SCO to roll out Internet access software |date=7 March 1994 |newspaper=Network World |url=https://books.google.com/books?id=gQ0EAAAAMBAJ&pg=PA6 |page=6}}</ref> To compete with [[Windows NT]] and [[Linux]], by 1997 SCO was distributing single-user licenses for educational use for $19, the cost of the CD-ROM, or completely free at trade shows.<ref name="collins19971101">{{Cite magazine |last=Collins |first=Ken |date=1997-11-01 |title=SCO OpenServer |url=https://www.linuxjournal.com/article/2427 |access-date=2025-05-12 |magazine=Linux Journal}}</ref> Due to its large installed base, SCO OpenServer 5 continues to be actively maintained by SCO with major updates having occurred as recently as September 2018.<ref name="definitive2018">
{{ cite web
| url = https://www.xinuos.com/wp-content/uploads/OpenServer5D2M1-ReleaseNotes-201809.pdf
| title = SCO OpenServer® 5 Definitive 2018
| work = [[Xinuos]]
| access-date = 2023-02-25 }}
</ref>

SCO OpenServer 6, based on the merging of AT&T [[UNIX]] [[System V]] Release 4.2MP and [[UnixWare|UnixWare 7]], was initially released by [[The SCO Group]] in 2005.  It includes support for large files, increased memory, and multi-threaded kernel (light-weight processes).  This merged codebase is referred to as [[UNIX System V#SVR5 / UnixWare 7|UNIX System V Release 5]] (SVR5) and was used only by SCO for OpenServer 6; SVR5 is not used by any other major developer or reseller.  SCO OpenServer 6 contains the [[UnixWare|UnixWare 7]]'s SVR5 kernel integrated with SCO OpenServer 5 application and binary compatibility, OpenServer 5 system administration, and OpenServer 5 user environments.

SCO OpenServer has primarily been sold into the small and medium business (SMB) market. It is widely used in small offices, [[point of sale]] (POS) systems, replicated sites, and backoffice [[database server]] deployments. Prominent larger SCO OpenServer customers include [[McDonald's]], [[Taco Bell]], [[Big O Tires]], [[Pizza Hut]], [[Costco]] pharmacy, [[NASDAQ]], The [[Toronto Stock Exchange]], [[Banco do Brasil]], many banks in [[Russia]] and [[China]], and the railway system of [[India]].<ref name="openservercustomers">{{cite web
| url = http://cdms-inc.com/pdfs/unix_windows.pdf
| title = Costco Cuts Costs with SCO OpenServer
| work = CDMS Inc
| access-date = 2010-04-12
| archive-url = https://web.archive.org/web/20100325234204/http://www.cdms-inc.com/pdfs/unix_windows.pdf
| archive-date = 2010-03-25
| url-status = dead
}}</ref><ref name="successstories">
{{ cite web
| url = http://www.sco.com/company/success/search.html?select_cat=1&category_submit=true
| title = OpenServer 5.0.7 Success Stories
| work = [[The SCO Group]]
| access-date = 2010-04-12 }}
</ref><ref name="groklawreport">{{cite web
| url = http://www.groklaw.net/articlebasic.php?story=20090611130638179
| title = Monday's Agenda in SCO's Bankruptcy and the Letter from Russia
| work = Groklaw
| access-date = 2010-04-12
| archive-url = https://web.archive.org/web/20100612020636/http://www.groklaw.net/articlebasic.php?story=20090611130638179
| archive-date = 2010-06-12
| url-status = dead
}}</ref>

===UnixWare merger===
[[File:SCO OpenServer 5.0.6 large dark blue commemorative cup (rotate).jpg|thumb|upright=0.7|left|Commemorative cup for the SCO OpenServer 5.0.6 release]]

SCO purchased the right to distribute the [[UnixWare]] system and its System V Release 4 code base from [[Novell]] in 1995. SCO was eventually able to re-use some code from that version of UnixWare in later releases of OpenServer. Until Release 6, this came primarily in the compilation system and the [[Uniform Driver Interface|UDI]] driver framework and the [[USB]] subsystem written to it.

By the end of the 1990s, there were around 15,000 [[value-added reseller]]s (VARs) around the world who provided solutions for customers of SCO's Unix systems.

SCO announced on August 2, 2000, that it would sell its Server Software and Services Divisions, as well as UnixWare and OpenServer technologies, to [[Caldera Systems]], Inc. The purchase was completed in May 2001. The remaining part of the SCO company, the Tarantella Division, changed its name to [[Tarantella, Inc.]], while Caldera Systems became [[Caldera International]], and subsequently in 2002, the [[SCO Group]].
{{clear}}

===Under The SCO Group===
[[Image:SCO OpenServer.png|thumb|200px|right|OpenServer logo at the time of The SCO Group]]

The SCO Group continued the development and maintenance of OpenServer. On June 22, 2005, OpenServer 6.0 was released, codenamed "Legend", the first release in the new 6.0.x branch. SCO OpenServer 6 is based on the UNIX [[UNIX_System_V#SVR5_/_UnixWare_7|System V Release 5]] kernel, a merged codebase of [[UNIX System V|UNIX System V Release 4.2MP]] and [[UnixWare|UnixWare 7]].  OpenServer 6.0 features multi-threading application support for C, C++, and Java applications through the POSIX interface. OpenServer 6 features kernel-level threading (not found in 5.0.x).

Some improvements over OpenServer 5 include improved SMP support (support for up to 32 processors), support for files over a terabyte on a partition (larger network files supported through NFSv3), better file system performance, and support for up to 64GB of memory.

OpenServer 6.0 maintains backward-compatibility for applications developed for Xenix 286 onwards.<ref name="os6qsg">
{{ cite web
| url = http://www.sco.com/products/openserver6/quickfacts.html
| title = SCO OpenServer Release 6 Quick Start Guide
| work = SCO Group Web Site
| access-date = 2009-10-27 }}
</ref>

The SCO Group went bankrupt in 2011, after a long [[SCO–Linux controversies|series of legal battles]].

===UnXis / Xinuos (2011–present)===
The rights to OpenServer, as well as UnixWare, were acquired by UnXis in 2011, which was later renamed [[Xinuos]].

In June 2015, Xinuos announced OpenServer 10, which is based on the [[FreeBSD]] 10 operating system. Simultaneously, Xinuos introduced a migration path for existing customers using older OS products. In December 2015, Xinuos released "definitive" versions of OpenServer 5, OpenServer 6, and UnixWare 7. 

In December 2017, Xinuos released "Definitive 2018" versions of OpenServer 6 and UnixWare 7, and in October 2018 OpenServer 5 Definitive 2018 was released. The "Definitive 2018" releases were a commitment by Xinuos to keep the legacy OS's updated and supported protecting the applications that customers need to continue to run. The Definitive 2018 products contain major updates over the Definitive releases, and an updated development kit was released which makes it easier to compile current packages for the Definitive 2018 products.

However, by 2023, OpenServer 10 was no longer listed as a product on Xinuos' home page, implying that it had been withdrawn from marketing.<ref>{{Cite web |last=Proven |first=Liam |date=17 Jan 2023 |title=Unix is dead. Long live Unix! |url=https://www.theregister.com/2023/01/17/unix_is_dead/ |access-date=2023-02-08 |website=www.theregister.com |language=en}}</ref>