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diff --git a/hurd/faq/old_hurd_faq.txt b/hurd/faq/old_hurd_faq.txt deleted file mode 100644 index e6c6cb5a..00000000 --- a/hurd/faq/old_hurd_faq.txt +++ /dev/null @@ -1,289 +0,0 @@ -The Unofficial (and no longer maintained) GNU Hurd FAQ, Version 0.13 - -Contributions by: - -Michael I. Bushnell <mib@gnu.org> -Len Tower <tower@gnu.org> -Trent Fisher <trent@gnurd.uu.pdx.edu> -jlr@usoft.spb.su -Remy Card <Remy.Card@masi.ibp.fr> -Louis-Dominique Dubeau <hallu@info.polymtl.ca> - -Original Document by: Derek Upham <upham@cs.ubc.ca> - - -============================== - -Contents: - -Q0. Where can I get the Unofficial GNU Hurd FAQ? -Q2. Where can I get a copy? -Q3. Why bother writing a new OS when we have Linux and 386/BSD? -Q4. What's all this about Mach 3.0 (and Mach 4.0)? -Q5. Where can I find more information? -Q6. What's a proper machine? -Q7. What sort of machines will run Hurd in the future? -Q8. What is the current development status? -Q9. What sort of system would we have if the Hurd was bootable today? - -============================== - -Q0. Where can I get the Unofficial GNU Hurd FAQ? - -The Unofficial Hurd FAQ (what you are reading now) is occasionally -posted to the USENET newsgroup, gnu.misc.discuss. It is also -available from - - http://www.enci.ucalgary.ca/~gord/hurd/hurd-faq.txt (Broken Link ?) - -If you don't have WWW access, you may send mail to me, Gordon -Matzigkeit <gord@enci.ucalgary.ca> with a subject line that reads: - - Subject: send hurd-faq - -You should receive a PGP-signed copy of the current version of this -document in a matter of minutes. - - -Q2. Where can I get a copy? - -To put it simply, you can't. It is still under development (by -Michael Bushnell, Roland McGrath and Miles Bader). It is almost, but -not quite, at the point where you can do real work on it. Keep your -fingers crossed. - -Some people have actually bootstrapped it, but the work is not easy, -and the current snapshot won't work until a new multiserver boot -mechanism is made. - -If you *really* want to try it, beware that it is still pre-alpha -code, and that it will likely crash on you. See Trent Fisher's Hurd -pages (under question 5) for the latest information. - - -Q3. Why bother writing a new OS when we have Linux and 386/BSD? - -For one thing, Linux and BSD don't scale well. Hardware designers are -shifting more and more toward multiprocessor machines for performance, -and standard Unix kernels do not provide much multiprocessor support. -The Hurd, on the other hand, runs on top of the Mach 3.0 micro-kernel -[[1]] from CMU. Mach was designed precisely for multiprocessing -machines, so its portability should carry over nicely to the Hurd. - -In addition, the Hurd will be considerably more flexible and robust -than generic Unix. Wherever possible, Unix kernel features have been -moved into unprivileged space. Once there, anyone who desires can -develop custom replacements for them. Users will be able to write and -use their own file systems, their own `exec' servers, or their own -network protocols if they like, all without disturbing other users. - -The Linux kernel has now been modified to allow user-level file -systems, so there is proof that people will actually use features such -as these. It will be much easier to do under the Hurd, however, -because the Hurd is almost entirely run in user space and because the -various servers are designed for this sort of modification. - - -Q4. What's all this about Mach 3.0 (and Mach 4.0)? - -As mentioned above, Mach is a micro-kernel, written at Carnegie Mellon -University. A more descriptive term might be a greatest-common-factor -kernel, since it provides facilities common to all ``real'' operating -systems, such as memory management, inter-process communication, -processes, and a bunch of other stuff. Unfortunately, the system -calls used to access these facilities are only vaguely related to the -familiar and cherished Unix system calls. There are no "fork", -"wait", or "sleep" system-calls, no SIGHUPs, nothing like that. All -this makes it rather difficult to, say, port GNU Emacs to a Mach box. - -The trick is, of course, to write an emulation library. Unix programs -can then use (what they think are) POSIX system calls and facilities -while they are really using Mach system calls and facilities. - -The simplest way of going about this is to take an ordinary Unix -kernel, open it up, and rip out all the machine-specific guts; any -time the Unix kernel talks to the machine, replace the code with calls -to the Mach micro-kernel. Run this fake kernel on a Mach machine and -you end up with something that looks and acts just like Unix (even to -GNU Emacs). Note that the Unix kernel we have implemented is just one -Really Big Mach program (called a single-server). - -The Hurd, on the other hand, breaks the giant Unix kernel down into -various Mach programs running as daemons. Working in concert with -facilities placed in the C library, these daemons provide all of the -POSIX system-calls and features; from the outside they look just like -a standard Unix kernel. This means that, for practical purposes, -anything that you can port to Linux will also port to the Hurd. - -Of course, if a user wishes to run his own daemons, he can do that as -well.... - -Mach 4.0 is an enhanced version of Mach 3.0, put out by the people at -the University of Utah. They are working on another free operating -system, and part of it includes an enhanced, more flexible version of -Mach. The Hurd has moved to Mach 4.0, which is good, because it is a -lot easier to build than 3.0 was. - -You can find more information on Mach by browsing the Hurd pages given -in the next answer, or by looking at the Project Mach and Flux -homepages at: - -Carnegie Mellon University (for Mach versions before 4.0): - - http://www.cs.cmu.edu/afs/cs.cmu.edu/project/mach/public/www/mach.html - -the University of Utah (for Mach 4.0): - - http://www.cs.utah.edu/projects/flux/mach4/html/ - - -Q5. Where can I find more information? - -The June 1995 GNU's Bulletin contains the following official -information: - - The GNU Hurd now runs programs native. We have implemented both - shared libraries using ELF, & the popular `ext2' file system used - by Linux. It can run GCC, `make', Emacs, & most other GNU - utilities. Progress is being made so rapidly that by the time you - read this it probably does much more. It is right on the verge of - being self-hosting (able to run on its own well enough to compile - its own source code, & be used for its own development). We have - much better device supportm [sic] & some new utilities, including a - fancy `ps' & `settrans'. For a complete system we still have much - more work to do, but we will make an alpha release as soon as the - network software is finished & shared libraries have been well - tested. We have a mailing list to announce progress; to be added - to it, ask `hurd-announce-request@gnu.org'. - -The Portland State University CS department (via Trent Fisher) -maintains a WWW server with various Hurd documents, including Michael -Bushnell's Hurd paper, all the collected GNU's Bulletins, and various -announcements posted to "gnu.misc.discuss". The top-level GNU page is - - http://www.cs.pdx.edu/~trent/gnu/gnu.html - -and the Hurd page is - - http://www.cs.pdx.edu/~trent/gnu/hurd/hurd.html - -People in Europe might want to try the GNU WWW server for DESY -Germany, first: - - http://info.desy.de/gnu/www - -This site lacks culled, Hurd-specific information at the moment, but -it does have the last two GNU's Bulletins plus lots of general -information. - -There is a snapshot of the Hurd development tree on -"alpha.gnu.ai.mit.edu" in the "/gnu" directory. It is updated as -significant changes are made, and not guaranteed to run. - -You can subscribe to the Hurd announcement list by sending a request -to "hurd-announce-request@gnu.org". This is a moderated list -for distributing Hurd info to ``all and sundry'', and anyone can join. -In addition, there is a private (invitation-only) list for developers -to coordinate their efforts. It's not even worth thinking about -unless you (a) have a lot of free time on your hands, (b) know Unix -internals and Mach very well, and (c) have a proper machine. - - -Q6. What's a proper machine? - -A ``proper machine'', at the moment, means an x86 box running Mach 3.0 -(or 4.0), with FreeBSD 2.x, NetBSD 1.x, or Linux. - -A single-server OS is no longer required for development because by -the time the Hurd bootstrap mechanism is finished, the Hurd will -probably be self-hosting. - -Linux, FreeBSD, or NetBSD will only be required to splat the Hurd -binaries onto a partition of some sort, and to provide a way of -transferring files to the Hurd until the networking code is ready. - - -Q7. What sort of machines will run Hurd in the future? - -The first thing a prospective Hurd machine needs is a Mach 3.0 port. -According to the most recent "comp.os.mach" FAQ (which hasn't been -updated since February 1994), the following chips have redistributable -Mach micro-kernels and device drivers: - - Intel 80x86 (ISA and PS/2 buses) - Motorola 68000 (Sun 3) - Motorola 88000 (Omron Luna) - DEC Vax - DEC Pmax (DECstation 3100) - DEC Alpha - MIPS R4000 (DECstation 5000 et al.) - IBM RS/6000 - Apple Macintosh - -IBM is planning to run WorkplaceOS (the OS/2 successor) over Mach 3.0 -on the PowerPC chip (closely related to the RS/6000), so the PowerPC -will likely be added to this list soon. The University of Utah has -ported Mach 4.0 to the HP700, but it is not yet stable. - -Sun Sparc machines have a redistributable Mach microkernel, but the -device drivers require a SunOS 4.1.1 source license. - -In addition, any prospective Hurd machine needs a port of the GNU C -library. Version 1.07.4 of the library can handle the following -chips: - - Intel 80x86 (BSD, Dynix, Hurd, SCO, SysV) - Motorola 68000 (HP BSD, NEWS, Sun 4) - MIPS R4000 (Ultrix) - Sun Sparc (Solaris 2, Sun 4) - DEC Alpha (OSF/1, mostly finished) - -So if the next Hurd snapshot is self-hosting, we will be able to run -it (in theory) on Intel 80x86s, Motorola 68000s, MIPS R4000s and DEC -Alphas. - -People who can port the Mach micro-kernel to new architectures are -encouraged to do so. People who can port the GNU C library to new -chips (a much larger group) are also encouraged to do so. You can -help out here without knowing anything about Mach or having any -special machine. Note that once the GNU C library exists for a new -chip, for _any_ OS, making a Hurd port later is simple (and making -ports to other chips becomes easier as well---the effects are -cumulative). - -By current indications, the other hardware requirements (RAM, disk -space, and the like) will be about the same as those of BSD 4.4. - - -Q8. What is the current development status? - -Please see Trent Fisher's Hurd pages for details. - - -Q9. What sort of a system would we have if the Hurd was bootable -today? - -Quite likely, if you already use an end-user system like Linux, -FreeBSD, or NetBSD, you'll be disappointed with the Hurd. It will -take some time before the OS hackers really get to work on -applications and major enhancements. - -But, rest assured, Hurd development should proceed very rapidly. - -Of course, if you think you can help, or you just enjoy neat stuff, -then you'll probably like the Hurd. When you actually understand a -fraction of what's going on behind the scenes, it's very impressive. - -All I'm saying is that I'm not expecting all the Windows '95 users in -the world to switch to the Hurd right away. Wait a little while, -maybe 5-6 years (ample time for GNUStep and Guile to be in use), and -GNU users everywhere will be very happy that the FSF proceeded with -the Hurd. :) - - -============================== - -Footnotes: - -[[1]] Yes, I know that ``micro-kernel'' is about as apt a description -as ``Reduced Instruction Set Chip'', but we're stuck with it. |