| KeyKOS | |
| Developer: | Tymshare (Norm Hardy, Bill Frantz, Charlie Landau) McDonnell Douglas Key Logic |
| Family: | Capability-based |
| Working State: | Discontinued |
| Df: | yes --> |
| Latest Release Version: | Final |
| Df: | yes --> |
| Marketing Target: | Research |
| Programmed In: | C |
| Language: | English |
| Update Model: | Compile from source code |
| Supported Platforms: | S/370 mainframe |
| Kernel Type: | Microkernel |
| Ui: | Command-line interface |
| Preceded By: | GNOSIS |
| Succeeded By: | Extremely Reliable Operating System (EROS), CapROS, Coyotos |
KeyKOS is a persistent, pure capability-based operating system for the IBM S/370 mainframe computers. It allows emulating the environments of VM, MVS, and Portable Operating System Interface (POSIX). It is a predecessor of the Extremely Reliable Operating System (EROS), and its successor operating systems, CapROS, and Coyotos. KeyKOS is a nanokernel-based operating system.[1]
In the mid-1970s, development of KeyKOS began at Tymshare, Inc., under the name GNOSIS. In 1984, McDonnell Douglas (MD) bought Tymshare. A year later MD spun off Key Logic, which bought GNOSIS and renamed it KeyKOS.[2]