Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!usc!snorkelwacker.mit.edu!ai-lab!life!mib From: mib@churchy.ai.mit.edu (Michael I. Bushnell) Newsgroups: comp.os.mach Subject: Re: OS kernel sources Message-ID: Date: 14 Nov 90 23:20:53 GMT References: <1990Nov5.215209.4489@pyro.ei.dupont.com> <884@sibyl.eleceng.ua.OZ> <1990Nov12.155727.6568@maverick.ksu.ksu.edu> <448@organpipe.UUCP> Sender: news@ai.mit.edu Distribution: comp.os.mach Organization: /home/fsf/mib/.organization Lines: 37 In-reply-to: tom@afthree.as.arizona.edu's message of 14 Nov 90 20:42:18 GMT In article <448@organpipe.UUCP> tom@afthree.as.arizona.edu (Thomas J. Trebisky) writes: Perhaps this means a waiting game for folks like me (Is it not true that the gnu project is also waiting for a "clean" Mach, at which time it becomes a candidate for their kernel.) But life is short, hence this appeal. Mach is composed of two large pieces. The first is the microkernel, and the second is the server. The microkernel implements device drivers, most of the vm system (but not actual paging), process scheduling, and interprocess communication (IPC). The machine independent source to the microkernel is currently under the CMU license agreement (more on that later). To run the microkernel, you also need a port to a specific platform. All existing ports, with the exception of that to the 386, use non-free code (often in device drivers). The server implements unix semantics: signals, networks, filesystems, uid's and pid's, etc. CMU's server is based on Unix and includes lots of Unix code. OSF's server is not Unix-based, but it is certainly not free either. The microkernel is not usable without some server to run on top of it. This is somewhat analagous to having an Xserver without any utilities or libraries which use it. The CMU license agreement (covering the microkernel, some programs like an RPC generator, and a couple of libraries) specifies that all users of the software must send improvements to CMU. The FSF is negotiating to make the CMU license agreement mutually acceptable to CMU and the FSF. To my knowledge, no one (including CMU) other than the FSF is considering implementing a free server on top of the Mach microkernel. -- Michael I. Bushnell \ This above all; to thine own self be true LIBERTE, EGALITE, FRATERNITE \ And it must follow, as the night the day, mike@unmvax.cs.unm.edu /\ Thou canst not be false to any man. CARPE DIEM / \ Farewell: my blessing season this in thee!