KeyKOS is a persistent, pure capability-based

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 ...

for the IBM

S/370 The IBM System/370 (S/370) is a model range of IBM mainframe computers announced on June 30, 1970, as the successors to the System/360 family. The series mostly maintains backward compatibility with the S/360, allowing an easy migration path f ...

mainframe

computer A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as C ...

s. It allows

emulating In computing, an emulator is hardware or software that enables one computer system (called the ''host'') to behave like another computer system (called the ''guest''). An emulator typically enables the host system to run software or use peri ...

the environments of VM,

MVS Multiple Virtual Storage, more commonly called MVS, was the most commonly used operating system on the System/370 and System/390 IBM mainframe computers. IBM developed MVS, along with OS/VS1 and SVS, as a successor to OS/360. It is unrelated ...

, and Portable Operating System Interface (

POSIX The Portable Operating System Interface (POSIX) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines both the system- and user-level application programming interf ...

). It is a predecessor of the

Extremely Reliable Operating System Extremely Reliable Operating System (EROS) is an operating system developed starting in 1991 at the University of Pennsylvania, and then Johns Hopkins University, and The EROS Group, LLC. Features include automatic data and process persistence, s ...

(EROS), and its successor

CapROS Capability-based Reliable Operating System (CapROS) is an operating system incorporating pure capability-based security. It features automatic persistence of data and processes, even across system reboots. Capability systems naturally support th ...

, and Coyotos. KeyKOS is a

nanokernel In computer science, a microkernel (often abbreviated as μ-kernel) is the near-minimum amount of software that can provide the mechanisms needed to implement an operating system (OS). These mechanisms include low-level address space management ...

-based operating system. In the mid-1970s, development of KeyKOS began at

Tymshare Tymshare, Inc (Matthew Heyer-Baker) was a time-sharing service and third-party hardware maintenance company competing with companies such as CompuServe, Service Bureau Corporation and National CSS. Tymshare developed or acquired various technolo ...

, Inc., under the name

GNOSIS Gnosis is the common Greek noun for knowledge ( γνῶσις, ''gnōsis'', f.). The term was used among various Hellenistic religions and philosophies in the Greco-Roman world. It is best known for its implication within Gnosticism, where it ...

. In 1984,

McDonnell Douglas McDonnell Douglas was a major American aerospace manufacturing corporation and defense contractor, formed by the merger of McDonnell Aircraft and the Douglas Aircraft Company in 1967. Between then and its own merger with Boeing in 1997, it produ ...

(MD) bought Tymshare. A year later MD spun off Key Logic, which bought GNOSIS and renamed it ''KeyKOS''.

References

External links

* , Norman Hardy
GNOSIS: A Prototype Operating System for the 1990s
a 1979 paper, Tymshare Inc.

a 1988 paper, Key Logic, Inc. {{Operating-system-stub Nanokernels Capability systems Microkernel-based operating systems