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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100644 index 4ebe019b..00000000 --- a/hurd/faq/old_hurd_faq.txt +++ /dev/null @@ -1,145 +0,0 @@ -The Unofficial (and no longer maintained) GNU Hurd FAQ, Version 0.13 - -Contributions by: - -Michael I. Bushnell 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? -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/ - - - -============================== - -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. |