Multiplan was released first for computers running CP / M ; it was developed using a Microsoft proprietary p-code C compiler as part of a portability strategy that facilitated ports to systems such as MS-DOS, Xenix, Commodore 64, Texas Instruments TI-99 / 4A, Radio Shack TRS-80 Model II, TRS-80 Model 100 ( on ROM ), Apple II, and Burroughs B-20 series.

When the original IBM-PC was created in 1980, there were three leading competing operating systems: PC-DOS, CP / M-86, and UCSD p-System, while Xenix was added in 1983-1984.

" Vaporware " was coined by a Microsoft engineer in 1982 to describe the company's Xenix operating system, and first appeared in print in a newsletter by computer expert Esther Dyson in 1983.

Ann Winblad, who was president of Open Systems Accounting Software, wanted to know if Microsoft planned to stop developing its Xenix operating system.

The initial port of Xenix was to the Zilog Z8000 series and subsequently to the Intel 8086 / 8088 architecture ported by The Santa Cruz Operation.

Microsoft Xenix originally ran on the PDP-11 ; the first port was for the Zilog Z8001 16-bit processor.

At the time, Xenix was based on AT & T's UNIX System III.

Version 2. 0 of Xenix was released in 1985 and was based on UNIX System V. An update numbered 2. 1. 1 added support for the Intel 80286 processor.

SCO's Xenix System V / 386 was the first 32-bit operating system available on the market for the x86 CPU Architecture.

In the late 1980s, Xenix was, according to The Design and Implementation of the 4. 3BSD UNIX Operating System, " probably the most widespread version of the UNIX operating system, according to the number of machines on which it runs ".

The last version of Xenix itself was 2. 3. 4.

Trusted Xenix was a variant developed by Trusted Information Systems which incorporated the Bell-La Padula model of multilevel security, and had a multilevel secure interface for the STU-III secure communications device ( that is, an STU-III connection would only be made available to applications running at the same privilege level as the key loaded in the STU-III ).

It was being used inside Microsoft ( for Windows and Xenix development ) in early 1984.

The first Sun workstations ( then based on the Motorola 68010 ) ran a V7 port by UniSoft ; the first version of Xenix for the Intel 8086 was derived from V7 ; and Onyx Systems soon produced a Zilog Z8000 computer running V7.

This version of Unix was not based on Xenix but via Interactive.

There may have been a Xenix version from some other company as back in 1979 Xenix was 8088 / 8086 based.

There was a Z8000 version of the Xenix Operating System

Analogous functionality was first developed on consumer level hardware by the Xenix operating system which supported multiple virtual consoles.

Santa Cruz Operation ( SCO ) was a software company based in Santa Cruz, California which was best known for selling three Unix variants for Intel x86 processors: Xenix, SCO UNIX ( later known as SCO OpenServer ), and UnixWare.

She went to Microsoft's offices, and asked two software engineers there, John Ulett and Mark Ursino, who confirmed that development of Xenix had stopped.

Xenix is a discontinued version of the Unix operating system, licensed by Microsoft from AT & T in the late 1970s.

Xenix varied from its 7th Edition origins by incorporating elements from BSD, and soon ( for a time ) possessed the most widely installed base of any Unix version due to the popularity of the inexpensive x86 processor.

* Xenix a version of the Unix computer operating system based on AT & T's UNIX System III, ported and distributed on the x86 PC architecture by SCO

The final version was Release 3. 2 in 1988, which added binary compatibility to Xenix on Intel platforms ; SCO OpenServer was based upon 3. 2, as was Interactive Systems Corporation ( ISC ) 386 / ix.

Because of this heritage, OS / 2 shares similarities with Unix, Xenix, and Windows NT in many ways.

In 1983 SCO ported Xenix to the Intel 8086 processor and licensed rights from Microsoft to be able to ship its first packaged Unix System, Xenix 1. 0 for the IBM PC XT.

Collectively, Xenix and SCO UNIX became the most installed flavor of Unix due to the popularity of the x86 architecture.

On Unix and DOS, B32 emulated all commonly used system calls of Data General's AOS / VS and RDOS operating systems, including implementing its own symbolic links on SCO Xenix and DOS.

The master boot record supported up to four partitions, and the other three were intended for other operating systems such as CP / M-86 and Xenix, which were expected to have their own partitioning utilities as did not support them.

While waiting for this new high-end system to develop, Microsoft would still receive licensing money from Xenix and OS / 2 sales.

Xenix 2. 3. 1 introduced support for i386, SCSI and TCP / IP.

* Xenix documentation and books for Download

* Intel Multibus System 320 for Xenix ( or iRMX86 )

Microsoft used this to interface MS Mail to an email system based on Xenix, for internal use.

The original release, written for the SCO Xenix operating system, quickly got ported to other platforms.

OpenServer 6. 0 maintains backward-compatibility for applications developed for Xenix 286 onwards.

; 1983: Profile 16 is released for the TRS-80 Model 16 running Xenix.

Microsoft continued to use Xenix internally, submitting a patch to support functionality in UNIX to AT & T in 1987, which trickled down to the code base of both Xenix and SCO UNIX.

IBM / Microsoft Xenix 1. 00 on 5¼-inch floppy disk

Microsoft is said to have used Xenix on Sun workstations and VAX minicomputers extensively within their company as late as 1992.

SCO first released SCO UNIX as a higher-end product, based on System V Release 3 and offering a number of technical advances over Xenix ; Xenix remained in the product line.

* Softpanorama take on Xenix development

The original accounts were all dialup shell accounts on Xenix Intel 80386 Tandy PC's, with email addresses in the format of user @ netcom. com.