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Nova - http://www.freesoftware.fsf.org/nova/
Effort to create a POSIX-like operating system atop the rtmk microkernel. [Open Source, GPL] |
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Quantix - http://quantix.sourceforge.net/
A POSIX microkernel with roots of the Mach and FreeBSD projects. [Open source, BSD-like] |
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OS/C - http://blake.prohosting.com/osc1/
Small Unix-like microkernel OS, process- and file-oriented, most of the system is built around the scheduler; designed to use minimum system resources to provide network services and utilities; written in C; source browsing and downloads available. [Open Source, GPL] |