View source for UNIX System III

{{Short description|Discontinued UNIX variant}}
{{Distinguish|Version 3 Unix}}
{{Use mdy dates|date=December 2023}} {{Use American English|date=December 2023}}
{{Infobox OS
| logo = SysIII-boot.png
| logo caption = UNIX System III on SIMH (PDP-11)
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| version of = <!-- For articles about releases of operating systems ONLY -->
| developer = [[American Telephone & Telegraph|AT&T]]'s Unix Support Group (USG)<!-- Name of main developer or sponsor-->
| family = [[Unix]]<!-- "Unix-like" or "Microsoft Windows" -->
| working state = Discontinued<!-- "Current", "Discontinued" (operating systems), or "No longer supported" (releases) -->
| source model = [[Closed source]]<!-- "Open source", "Closed source", or "Shared source" -->
| released = {{Start date and age|1980}}<ref>{{cite book |author=<!--Not stated--> |editor-first1=T. A. |editor-last1=Dolotta |editor-first2=S. B. |editor-last2=Olsson  |editor-first3=A. G. |editor-last3=Petruccelli |date=June 1980 |title=UNIX User's Manual, Release 3.0 |url=https://archive.org/details/bitsavers_attunixSysalRelease3Jun80_33886798 |location=Murray Hill, NJ 07974 |publisher=Laboratory 364, Bell Telephone Laboratories, Incorporated}}</ref>
| discontinued = <!-- DON'T use this for articles about releases of operating systems -->
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| update model = <!-- APT, Windows Update, etc. -->
| package manager = <!-- dpkg, rpm, Windows installer, etc. -->
| supported platforms = [[Digital Equipment Corporation|DEC]] [[PDP-11]] and [[VAX]]<!-- IA-32, x64, Itanium, ARM, etc. -->
| kernel type = <!-- Hybrid, Monolithic, Microkernel, Exokernel, Nanokernel, etc. -->
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| ui = [[Command-line interface]]
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| succeeded by = [[UNIX System V]]
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'''UNIX System III''' (or '''System 3''') is a discontinued version of the [[Unix]] operating system released by [[AT&T Corporation|AT&T]]'s Unix Support Group (USG).

AT&T announced System III in late 1981,<ref name="fiedler198310">{{cite magazine | url=https://archive.org/stream/byte-magazine-1983-10/1983_10_BYTE_08-10_UNIX#page/n133/mode/2up | title=The Unix Tutorial / Part 3: Unix in the Microcomputer Marketplace | magazine=[[Byte (magazine)|BYTE]] |volume=8 |issue=10 | date=October 1983 | access-date=30 January 2015 | author=Fiedler, Ryan | pages=132}}</ref> and it was first released outside of [[Bell Labs]] in 1982. UNIX System III was a mix of various AT&T Unix systems: [[Version 7 Unix]], [[PWB/UNIX]] 2.0, [[CB UNIX]] 3.0, [[Multi-Environment Real-Time|UNIX/RT]] and [[UNIX/32V]]. System III supported the [[Digital Equipment Corporation|DEC]] [[PDP-11]] and [[VAX]] computers.

The system was apparently called System III because it was considered the outside release of UNIX/TS 3.0.1 and CB UNIX 3 which were internally supported Bell Labs Unices; its manual refers to it as '''UNIX Release 3.0''' and there were no Unix versions called System I or System II. There was no official release of UNIX/TS 4.0 (which would have been ''System IV'') either,<ref>{{cite newsgroup
|title = UNIX History
|author = Dale Dejager
|date = 1984-01-16
|newsgroup = net.unix
|url = http://groups.google.com/group/net.unix/msg/b80689d4b3bff13f?dmode=source
}}</ref><ref>{{cite book |title=Modern Operating Systems |last=Tanenbaum |first=Andrew S. |quote=Whatever happened to System IV is one of the great unsolved mysteries of computer science. |location=Upper Saddle River, NJ |publisher=[[Prentice Hall]] |edition=2nd |year=2001 |page=[https://archive.org/details/modernoperatings00tane/page/675 675] |isbn=0-13-031358-0 |url-access=registration |url=https://archive.org/details/modernoperatings00tane/page/675 }}</ref> so System III was succeeded by [[UNIX System V|System V]], based on UNIX/TS 5.0.

System III introduced new features such as [[named pipe]]s, the [[uname]] system call and command, and the [[run queue]]. It also combined various improvements to [[Version 7 Unix]] by outside organizations. However, it did not include notable additions made in [[Berkeley Software Distribution|BSD]] such as the [[C shell]] (csh) and screen editing.

Third-party variants of System III include (early versions of) [[HP-UX]], [[IRIX]], [[Interactive Systems Corporation|IS/3]] and [[PC/IX]], [[PC-UX]], [[PERQ|PNX]], [[SINIX]], [[Venix]] and [[Xenix]].

==References==
{{Reflist}}

==External links==
* {{cite magazine |url= https://archive.org/details/login_apr00/page/n73/mode/1up |title=20 Years Ago in UNIX |author-link=Peter H. Salus |first=Peter H. |last=Salus |magazine = LOGIN |date= April 2000 | volume=25 |number = 2 | pages = 72–73 }}
*System III source code
** {{cite web
|url = http://a.papnet.eu/UNIX/sysIII_pdp11/Installation
|title = UNIX System III on PDP-11
|archiveurl = https://web.archive.org/web/20190411165355/http://a.papnet.eu/UNIX/sysIII_pdp11/Installation
|archivedate = 11 April 2019
|url-status = dead}}
** {{cite web
|url = http://a.papnet.eu/UNIX/sysIII_vax/Installation
|title = UNIX System III on VAX
|archiveurl = https://web.archive.org/web/20190411165353/http://a.papnet.eu/UNIX/sysIII_vax/Installation
|archivedate = 11 April 2019
|url-status = dead}}

{{Bell Unix}}
{{Unix-like}}

[[Category:Bell Labs Unices]]
[[Category:Discontinued operating systems]]
[[Category:1982 software]]