GCOS (Genereal Comprehensive Operating System) was originally a quick-and-dirty clone of System/360 disk operating system that emerged from General Electric around 1970. It was originally called GECOS (the General Electric Comprehensive Operating System), and was later kluged to support primitive timesharing and transaction processing. After the buyout of GE's computer division by Honeywell, the name was changed to General Comprehensive Operating System (GCOS). Other OS groups at Honeywell began referring to it as "God's Chosen Operating System", allegedly in reaction to the GCOS crowd's attitude about the superiority of their product. In a fiercely fought intracorporate political battle, GCOS prevailed over Multics, Honeywell's other operating system at the time, to become Honeywell's lead operating system offering. GCOS later played a major role in keeping Honeywell a dismal also-ran in the mainframe market, and was itself mostly ditched for UNIX in the late 1980s when Honeywell began to retire its aging big iron designs.
While GCOS is no longer in use, a small remnant of it is remains on UNIX (and UNIX-like systems such as Linux). Some early UNIX systems at Bell Labs used GCOS machines for print spooling and various other services; in order to accomodate this a field was added to /etc/passwd to carry GCOS ID information. This field was called the "GECOS field" and survives today in UNIX as the pw_gecos member used to store the user's full name and other human-ID information.
Source
- The Jargon File version 4.3.1, ed. ESR
