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(operating system)
/jee'kohs/ An operating system developed by General Electric from 1962; originally called GECOS (the General Electric Comprehensive Operating System).

The GECOS-II operating system was developed by General Electric for the 36-bit GE-635 in 1962-1964. Contrary to rumour, GECOS was not cloned from System/360 the GE-635 architecture was very different from the IBM 360 and GECOS was more ambitious than DOS/360.

GE Information Service Divsion developed a large special multi-computer system that was not publicised because they did not wish time sharing customers to challenge their bills. Although GE ISD was marketing DTSS - the first commercial time sharing system - GE Computer Division had no license from Dartmouth and GE-ISD to market it to external customers, so they designed a time-sharing system to sell as a standard part of GECOS-III, which replaced GECOS-II in 1967. GECOS TSS was more general purpose than DTSS, it was more a programmer's tool (program editing, e-mail on a single system) than a BASIC TSS.

The GE-645, a modified 635 built by the same people, was selected by MIT and Bell for the Multics project. Multics' infancy was as painful as any infancy. Bell pulled out in 1969 and later produced Unix.

After the buy-out of GE's computer division by Honeywell, GECOS-III was renamed GCOS-3 (General Comprehensive Operating System). Other OS groups at Honeywell began referring to it as "God's Chosen Operating System", allegedly in reaction to the GCOS crowd's uninformed and snotty attitude about the superiority of their product. GCOS won and this led in the orphaning and eventual death of Honeywell Multics.

Honeywell also decided to launch a new product line called Level64, and later DPS-7. It was decided to mainatin, at least temporarily, the 36-bit machine as top of the line, because GCOS-3 was so successfull in the 1970s. The plan in 1972-1973 was that GCOS-3 and Multics should converge. This plan was killed by Honeywell management in 1973 for lack of resources and the inability of Multics, lacking databases and transaction processing, to act as a business operating system without a substantial reinvestment.

The name "GCOS" was extended to all Honeywell-marketed product lines and GCOS-64, a completely different 32-bit operating system, significanctly inspired by Multics, was designed in France and Boston. GCOS-62, another different 32-bit low-end DOS level was designed in Italy. GCOS-61 represented a new version of a small system made in France and the new DPS-6 16-bit minicomputer line got GCOS-6.

When the intended merge between GCOS-3 and Multics failed, the Phoenix designers had in mind a big upgrade of the architecture to introduce segmentation and capabilities. GCOS-3 was renamed GCOS-8, well before it started to use the new features which were introduced in next generation hardware.

The GCOS licenses were sold to the Japanese companies NEC and Toshiba who developed the Honeywell products, including GCOS, much further, surpassing the IBM 3090 and IBM 390.

When Honeywell decided in 1984 to get its top of the range machines from NEC, they considered running Multics on them but the Multics market was considered too small. Due to the difficulty of porting the ancient Multics code they considered modifying the NEC hardware to support the Multics compilers.

GCOS3 featured a good Codasyl database called IDS (Integrated Data Store) that was the model for the more successful IDMS.

Several versions of transaction processing were designed for GCOS-3 and GCOS-8. An early attempt at TP for GCOS-3, not taken up in Europe, assumed that, as in Unix, a new process should be started to handle each transaction. IBM customers required a more efficient model where multiplexed threads wait for messages and can share resources. Those features were implemented as subsystems.

GCOS-3 soon acquired a proper TP monitor called Transaction Driven System (TDS). TDS was essentially a Honeywell development. It later evolved into TP8 on GCOS-8. TDS and its developments were commercially successful and predated IBM CICS, which had a very similar architecture.

GCOS-6 and GCOS-4 (ex-GCOS-62) were superseded by Motorola 68000-based minicomputers running Unix and the product lines were discontinued.

In the late 1980s Bull took over Honeywell and Bull's management choose Unix, probably with the intent to move out of hardware into middleware. Bull killed the Boston proposal to port Multics to a platform derived from DPS-6. Very few customers rushed to convert from GCOS to Unix and new machines (of CMOS technology) are still to be introduced in 1997 with GCOS-8. GCOS played a major role in keeping Honeywell a dismal also-ran in the mainframe market.

Some early Unix systems at Bell Labs used GCOS machines for print spooling and various other services. The field added to "/etc/passwd" to carry GCOS ID information was called the "GECOS field" and survives today as the "pw_gecos" member used for the user's full name and other human-ID information.


(General Comprehensive OS) An operating system from Bull that, originally used in its minis and mainframes, has migrated to its Intel-based servers. GCOS was originally developed by GE in the early 1970s as GECOS (GE Comprehensive OS), then changed to General Comprehensive OS when Honeywell took over GE's computer division. Later, Bull acquired Honeywell's computer products. See Bull.
References in periodicals archive ?
2010b: Guideline for the generation of datasets and products meeting GCOS requirements.
The results of the GCOS portion of the survey instrument revealed the dominant Motivational Orientation among dental hygienists in both Utah and Idaho was Autonomy.
Por otra parte, la GCOS ha sido utilizada en estudios referidos a la autonomia y el bienestar psicologico de las personas.
Bull says that it will be working to give GCOS customers more performance and better bang for the buck in the future, which might mean the "Madison" 9MB chip due later this year and the dual-core "Montecito" Itaniums due next year.
2011: Report of the Third GCOS Reference Upper Air Network Implementation and Coordination Meeting (GRUAN ICM-3).
The EE-Instrument Interface Suite has built-in, easy-to-use wizards capable of registering sample data automatically from spreadsheets and CSV files, converting and moving data into the Affymetrix GCOS.
This Framework Agreement is to maintenance and renewal of equipment, the right to use the concession, environment software maintenance GCOS 7 and the provision of additional services associated.
UC4:global supports comprehensive process management for business solutions such as SAP, PeopleSoft, Oracle, and Siebel, as well as all operating systems, including Windows, Linux, Unix, OpenVMS, HP NonStop Kernel, OS/400, MPE/ix, z/OS, BS2000/OSD and GCOS 8.
Astrea intended to replace the trade GCOS / Heart PackBase / IDS2 of Ncjv2 and to streamline and urbanize its complex and diverse ecosystem in a modern platform.
forerunner of Syncrude); Process Equipment Supplier to GCOS (Suncor) through Bechtel Corporation; Manager of the Industrial Engineering Division of Associated Engineering Services Ltd.