THEOS, which translates from Greek as "God", is an

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...

which started out as OASIS, a

microcomputer A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PC ...

for small computers that use the

Z80 The Z80 is an 8-bit microprocessor introduced by Zilog as the startup company's first product. The Z80 was conceived by Federico Faggin in late 1974 and developed by him and his 11 employees starting in early 1975. The first working samples were ...

processor. When the operating system was launched for the IBM Personal Computer/AT in 1982, the decision was taken to change the name from OASIS to THEOS, short for ''THE Operating System''.

History

OASIS

The ''OASIS operating system'' was originally developed and distributed in 1977 by

Phase One Systems Phase or phases may refer to: Science *State of matter, or phase, one of the distinct forms in which matter can exist *Phase (matter), a region of space throughout which all physical properties are essentially uniform * Phase space, a mathematic ...

Oakland, California Oakland is the largest city and the county seat of Alameda County, California, United States. A major West Coast of the United States, West Coast port, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, the third ...

(President Howard Sidorsky). OASIS was developed for the

processor and was the first multi-user operating system for 8-bit microprocessor based computers (Z-80 from

Zilog Zilog, Inc. is an American manufacturer of microprocessors and 8-bit and 16-bit microcontrollers. It is also a supplier of application-specific embedded system-on-chip (SoC) products. Its most famous product is the Z80 series of 8-bit microp ...

). "OASIS" was a backronym for "Online Application System Interactive Software". OASIS consisted of a multi-user operating system, a powerful Business Basic/Interpreter, C compiler and a powerful text editor. Timothy Williams developed OASIS and was employed at Phase One. The market asked for 16-bit systems but there was no real 16-bit multi-user OS for 16-bit systems. Every month Phase One announced OASIS-16 but it did not come. One day Timothy Williams claimed that he owned OASIS and started a court case against Phase One and claimed several million

U.S. dollars The United States dollar (symbol: $; code: USD; also abbreviated US$ or U.S. Dollar, to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official ...

. Sidorsky had no choice and claimed Chapter 11. The court case took two years and finally the ruling was that Timothy Williams was allowed to develop the 16-bit version of OASIS but he was not allowed to use the OASIS name anymore. David Shirley presented an alternative history at the Computer Information Centre, an OASIS distributor for the UK in the early 1980s. He said Timothy Williams developed the OASIS operating system and contracted with Phase One Systems to market and sell the product. Development of the 16-bit product was underway, but the product was prematurely announced by POS. This led to pressure to release OASIS early, when it was still not properly debugged or optimised. (OASIS 8-bit was quite well optimised by that point, with many parts hand-coded in Z80 assembler, but that meant then-new 16-bit systems performed nowhere near as well as their 8-bit counterparts). This situation led to Williams becoming dissatisfied with the Phase One company at the time, and forming his own company to market and support the 16-bit OASIS. The company was initially called Oasis Technologies, until Phase One took action to protect the name. Rather than fight a long and expensive court battle, the company and product was renamed "THEOS". Williams created a new company and product name: "THEOS" meaning "the OS" in the sense of "the one" ("Theos" is Greek for " God"). While Williams and Sidorsky where fighting in the court the manufacturers had no 16-bit multi-user OS. That led to the agreement between

Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...

and

Santa Cruz Operation The Santa Cruz Operation, Inc. (usually known as SCO, pronounced either as individual letters or as a word) was an American software company, based in Santa Cruz, California, that was best known for selling three Unix operating system variants ...

to make a new operating system based on Version 7 Unix from

Bell Labs Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by mult ...

. Microsoft purchased a license for Version 7 UNIX from AT&T in 1978, and announced on August 25, 1980, that it would make it available for the

16-bit 16-bit microcomputers are microcomputers that use 16-bit microprocessors. A 16-bit register can store 216 different values. The range of integer values that can be stored in 16 bits depends on the integer representation used. With the two mos ...

microcomputer market. Because Microsoft was not able to license the "UNIX" name itself, called

Xenix Xenix is a discontinued version of the Unix operating system for various microcomputer platforms, licensed by Microsoft from AT&T Corporation in the late 1970s. The Santa Cruz Operation (SCO) later acquired exclusive rights to the software, and ...

. Microsoft would distribute the product via Larry Michels and his son Doug Michels (

). Seiko also lost patience with THEOS and Williams, and decided to make their own OASIS 16-bit version and hired Dr. Jeffrey Bahr. When Xenix and THEOS became available Seiko did decide to leave this market. Jeffrey Bahr started CET which went on with the development of the 16-bit OASIS compatible software. CET software was complete compatible with OASIS/THEOS and allowed these users to go into the Unix and Microsoft world. CET acquired the Phase one company. Also, Phase One Systems licenses a porting tool called

CET Basic CET or cet may refer to: Places * Cet, Albania * Cet, standard astronomical abbreviation for the constellation Cetus * Colchester Town railway station (National Rail code CET), in Colchester, England Arts, entertainment, and media * Comcast En ...

. CET Basic is compatible with THEOS BASIC, MultiUser BASIC, OASIS BASIC, and UX-BASIC. This means you can keep most of your existing source code, and using W/32 BASIC, recompile your THEOS, OASIS, or UX-BASIC programs to work under additional operating systems such as

Microsoft Windows Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for serv ...

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which ...

SCO UNIX Xinuos OpenServer, previously SCO UNIX and SCO Open Desktop (SCO ODT), is a closed source computer operating system developed by Santa Cruz Operation (SCO), later acquired by SCO Group, and now owned by Xinuos. Early versions of OpenServer were ...

THEOS

THEOS operating systems have been distributed by

THEOS Software Corporation THEOS, which translates from Greek as "God", is an operating system which started out as OASIS, a microcomputer operating system for small computers that use the Z80 processor. When the operating system was launched for the IBM Personal Comp ...

in Walnut Creek, California, since 1983. As of 2003, Phase One Systems publishes software development tools for THEOS(R) systems. As well as porting tools, Phase One Systems distributed the Freedom query package and Control database package for THEOS systems, used to bring SQL-like data extraction tools to third-party software packages. THEOS was introduced in Europe by

Fujitsu is a Japanese multinational information and communications technology equipment and services corporation, established in 1935 and headquartered in Tokyo. Fujitsu is the world's sixth-largest IT services provider by annual revenue, and the la ...

and other hardware manufacturers 30 years ago, and is distributed by a number of distributors in Great Britain, Spain, Portugal, Germany, Italy and more. The 'current' version is THEOS Corona Commercial Release 6, which was released in December 2008, and a number of updates have been released since that time. The current Windows Workstation Client (as of May 2009) is version 3.16 from July 2003.

Features

Originally written in the late 1970s by Timothy S. Williams as a low-cost alternative to the more expensive mini- and mainframe- computers that were popular in the day, OASIS provided time-sharing multiuser facilities to allow several users to utilise the resources of one computer. Similar in concept to MP/M or

UNIX Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and ot ...

, THEOS uses external device drivers rather than a kernel, allowing it to be more portable to other environments, though support has been primarily directed towards industry-standard hardware (i.e. PC's). THEOS is specifically aimed at small business users, with a wide range of vertical-market applications packages being developed and supported by individuals and companies. The languages distributed with THEOS include THEOS Multi-User

Basic BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...

and C. A powerful EXEC shell language can be used for task automation or to produce a turnkey system. A number of security features exist, including dynamic passwords (where the password includes part of the date or time, or client IP address, or other dynamic elements), allow/deny security, a comprehensive inbound and outbound firewall, and an option to require a certain level of encryption in the workstation connection. In addition, the object file format is proprietary, and the operating system uses

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 seri ...

"protected mode" to further increase defence against buffer overrun attacks.

Commands

The following list of commands are supported by the THEOS/OASIS Command String Interpreter (CSI).THEOS/OASIS User′s Handbook
/ref> * ACCOUNT * ARCHIVE * ASSIGN * ATTACH * BACKUP *

BASIC BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...

* BULKERA * CACHE * CADVERF * CHANGE * CLASS * COMPARE * COPYFILE * CREATE * CSI *

DEBUG In computer programming and software development, debugging is the process of finding and resolving '' bugs'' (defects or problems that prevent correct operation) within computer programs, software, or systems. Debugging tactics can involve int ...

* EDIT *

ERASE Erase may refer to: *Data erasure, a method of software-based overwriting that completely destroys all electronic data *Data remanence, the residual representation of data that has been, in some way, nominally erased or removed * ''Erase'' (album ...

* ERRMSG * EXEC * FILELIST * FILT8080 * FORCE * GETFILE *

HELP Help is a word meaning to give aid or signal distress. Help may refer to: Arts, entertainment, and media Films * ''Help'' (2010 film), a Bollywood horror film * ''Help'' (2021 theatrical film), a British psychological thriller film * '' ...

* INITDISK * INITTAPE * KILL * LIST * LOGOFF * LOGON * MAILBOX * MSG * PEEK * RECEIVE *

RENAME Rename may refer to: * Rename (computing), rename of a file on a computer * RENAME (command), command to rename a file in various operating systems * Rename (relational algebra) In relational algebra, a rename is a unary operation written as \r ...

* REPAIR * RESTORE * SCRIPT * SEND * SET * SHOW * SPOOLER * START * STOP * SYSGEN * TERMINAL

Reception

BYTE The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit ...

'' in 1985 stated that "the functionality of THEOS is somewhere between

MS-DOS MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few ope ...

and

". The magazine criticized the documentation's quality, and concluded that the price was too high compared to other multiuser operating systems for the PC such as Pick and

Coherent Coherence, coherency, or coherent may refer to the following: Physics * Coherence (physics), an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference * Coherence (units of measurement), a deri ...

References

External links

THEOS Software CorporationHistoria de OASIS®/THEOS® CoronaOASIS Users' Group Archive
February 1981 through November 1985 {{Real-time operating systems Proprietary operating systems X86 operating systems 1977 software