From: jkp@cs.HUT.FI (Jyrki Kuoppala)
Subject: Re: What is Linux?
Reply-To: jkp@cs.HUT.FI (Jyrki Kuoppala)
Organization: Helsinki University of Technology, Finland
Date: Fri, 8 Jan 1993 14:52:19 GMT

In article <1993Jan8.135459.20303@ccd.harris.com>, stp@controls (Stephen T. Pierce) writes:
>
>Could someone give a good review for those of us rather unfamiliar with Linux?
>It would help to know what users think, about limitations, etc.

(added alt.uu.tools because Linux can be a valuable tool for many
purposes useful to UU-like activities)

This posting contains the Linux infosheet and the comp.os.linux meta-FAQ.

This is the infosheet for Linux:

To: Linux-Activists@BLOOM-PICAYUNE.MIT.EDU
Crossposted-To: comp.os.linux.announce,news.answers
From: mdw@db.TC.Cornell.EDU (Matt Welsh)
Subject: Linux INFO-SHEET
Date: Sat, 2 Jan 1993 04:01:02 GMT

Archive-name: linux-faq/info-sheet
Last-modified: 1992-12-10


LINUX INFORMATION SHEET
by Lars Wirzenius (lars.wirzenius@helsinki.fi) and
Matt Welsh (mdw@tc.cornell.edu).
Earlier versions done by other people.


0. About this INFO-SHEET

        This INFO-SHEET tries to be a concentrated distillation of the
        necessary information one needs to decide whether Linux is a
        suitable operating system for you.  It is kind of an
        advertisment, although hopefully more truthful.

        This INFO-SHEET is posted every other week to the
        comp.os.linux and comp.os.linux.announce newsgroups.

1. What Is Linux?

        Linux is a freely distributable UNIX clone.  It is mostly
        compatible with System V and POSIX specifications, but is
        quite compatible with BSD as well.

        The Linux kernel has been written from scratch, and therefore
        does not contain any proprietary code, either from AT&T,
        MINIX, or other places--not in the kernel, the compiler, the
        utilities, or the libraries.  For this reason it can be made
        available with the complete source code via anonymous FTP.
        (The software that runs under Linux, on the other hand, is
        mostly already existing Unix freeware, with a lot of stuff
        coming from the GNU Project.)

        Linux runs only on 386/486 machines with an ISA or EISA bus;
        porting to other architectures is likely to be difficult, as
        the kernel makes extensive use of 386 memory management and
        task primitives (but there are people working on at least an
        Amiga port).  MCA is not supported because there is little
        available documentation (especially for poor-hacker -friendly
        prices) about it.  (See below for more information on
        hardware.)

        Linux is still in beta testing and therefore not really
        considered to be suitable for production work (although it is
        used for that anyway).  There are still bugs in the system,
        and since it develops rapidly, new bugs creep up often.
        However, some releases are quite stable, and you can stay with
        those if you don't want to be on the bleeding edge.  Some
        sites have been running Linux systems continuously doing real
        work for more than 50 days, without a single reboot, crash, or
        other lock-up!

        One thing to be aware of is that Linux is developed using an
        open and distributed model, instead of a closed and
        centralised model like much other software.  This means that
        the current development version is always public (with up to a
        week or two's delay) so that anybody can use it.  The result
        is that whenever a version with new functionality is released,
        it almost always contains bugs, but it also results in a very
        rapid development so that the bugs are found and corrected
        quickly, sometimes in hours.

        (The closed and centralised model means that there is only one
        person or team working on the project, and they only release
        software that they think is working well.  Often this leads to
        long intervals between releases, long waiting for bug fixes, and
        slower development.  Of course, the latest release of such
        software is often of higher quality.)

        As of December 10 the current version is 0.98 patchlevel 6.

2. Linux Features

      * multitasking: several programs running at once
      * multiuser: several users on the same machine at once (and NO
        two-user licenses!)
      * memory protection between processes, so that one program can't
        bring the whole system down
      * core dumps for post-mortem analysis (using a debugger on a
        program after it has crashed)
      * demand loading of executables: only read in those parts of a
        program that are actually used
      * virtual memory using paging (not swapping whole processes) to
        disk, to a separate partition or a file in the filesystem, or
        both, and with a possibility to add more swapping areas at
        runtime (they're still called swapping areas)
      * shared pages among executables with copy-on-write
      * shared libraries (static too, of course)
      * a unified memory pool for user programs and disk cache (so
        that all free memory can be used for caching, and the cache
        can be reduced when running large programs)
      * mostly compatible with POSIX, System V, and BSD at the source
        level
      * all source code is available, including the whole kernel and
        all drivers, the development tools and all user programs;
        also, all of it is freely distributable
      * POSIX job control
      * pseudoterminals (pty's)
      * 387-emulation in the kernel so that programs don't need to
        include math emulation packages
      * support for many national or customized keyboards, and it's
        fairly easy to add new ones
      * runs in protected mode of the 386
      * multiple virtual consoles: several independent login sessions
        through the console, you switch by pressing a hot-key
        combination (not dependent on video hardware)
      * normal and extended Minix filesystems (the extended version
        supports up to 4 TB, filenames up to 255 chars)
      * transparent access to MS-DOS partitions (or OS/2 FAT
        partitions) via a special filesystem: you don't need any
        special commands to use the MS-DOS partition, it looks just
        like a normal Unix filesystem (except for funny restrictions
        on filenames, permissions, and so on)
      * CD-ROM filesystem
      * Xenix filesystem
    
In addition the following are being worked on (in various states of
usability):

      * networking (TCP/IP, including ftp, telnet, etc)
      * compressed file system
      * Xenix binary compatibility

3. Hardware Issues

    Minimal configuration

        The following is probably the smallest possible configuration
        that Linux will work on: 386SX/16, 2 MB RAM, 1.44 MB or 1.2 MB
        floppy, any supported video card (+ keyboards, monitors, and
        so on of course).  This should allow you to boot and test
        whether it works at all on the machine, but you won't be able
        to do anything useful.

        In order to do something, you will want some hard disk space
        as well, 5 to 10 MB should suffice for a very minimal setup
        (with only the most important commands and perhaps one or two
        small applications installed, like, say, a terminal program).
        This is still very, very limited, and very uncomfortable, as
        it doesn't leave enough room to do just about anything.  (It's
        definitely not recommended for anything but testing if things
        work, and of course to be able to brag about small resource
        requirements. :-)

    Usable configuration

        If you are going to run computationally intensive programs,
        such as gcc, X, and TeX, you will probably want a faster
        processor than a 386SX/16, but even that should suffice if you
        are patient.

        In practice, you need at least 4 MB of RAM if you don't use X,
        and 8 MB if you do.  Also, if you want to have several users
        at a time, or run several large programs (compilations for
        example) at a time, you may want more than 4 MB of memory.  It
        will still work with a smaller amount of memory (should work
        even with 2 MB), but it will use virtual memory and that will
        be so slow it's unusable.

        The amount of hard disk you need depends on what software you
        want to install.  The normal basic set of Unix utilities,
        shells, and administrative programs should be comfortable in
        less than 10 MB, with a bit of room to spare for user files.
        For a more complete system, the SLS documentation reports that
        a full base system without X fits into 20 MB, and with X into
        40 MB (this is only binaries).  Add the whatever space you
        want to reserve for user files.

        Add more memory, more hard disk, a faster processor and other
        stuff depending on your needs, wishes and budget to go beyond
        the merely usable.

    Supported hardware

        Note: This section is still sketchy.  Feedback appreciated.

        CPU: Anything that runs 386 protected mode programs (all
        models of 386s and 486s should work; 286s don't work, and
        never will).

        Architecture: ISA or EISA bus (you still need an ISA-bus hard
        disk controller, though).  MCA (aka PS/2) does not work.
        Local bus should work.

        RAM: Theoretically up to 1 GB (but more than 16 MB requires a
        kernel recompilation).  (It will work with "too much" memory,
        but it won't use it.)

        Data storage: Generic AT drives (IDE, 16 bit HD controllers
        with MFM or RLL), generic XT controllers (8 bit controllers
        with MFM or RLL) need a special driver (not currently part of
        the standard kernel), SCSI hard disks and CD-ROM.  Supported
        SCSI cards: Adaptec 1542 (but not 1522), the 1740 in extended
        (not 1542 compatible) mode, Seagate ST-01 and ST-02, Future
        Domain TMC-88x series (or any board based on the TMC950 chip)
        and TMC1660/1680, Ultrastor 14F, and Western Digital wd7000.
        SCSI and QIC-02 tapes.

        Video: VGA, EGA, CGA, or Hercules (and compatibles) work in
        text mode.  For graphics and X, there is support for (at
        least) EGA, normal VGA, some super-VGA cards (most of the
        cards based on ET3000, ET4000, Paradise, and some Trident
        chipsets), some S3 cards (not Diamond Stealth, because the
        manufacturer won't tell how to program it) and 8514/A.  (Linux
        uses the Xfree86 X server, so that determines what cards are
        supported.)

        Other hardware: SoundBlaster, AST Fourport cards (with 4 serial
        boards), several flavours of bus mice (Microsoft, Logitech,
        PS/2).

4. An Incomplete List of Ported Programs and Other Software

        Most of the common Unix tools and programs have been ported to
        Linux, including almost all of the GNU stuff and many X
        clients from various sources.  Actually, ported is often too
        strong a word, since many programs compile out of the box
        without modifications, or only small modifications (maybe
        being POSIXy and following standards isn't so bad :).
        Unfortunately, there are not very many end-user applications.
        Nevertheless, here is an incomplete list of software that is
        known to work under Linux.

        Basic Unix commands: ls, tr, sed, awk and so on (you name it,
        we've probably got it).

        Development tools: gcc, gdb, make, bison, flex, perl,
        rcs, cvs, gprof.

        Graphical environments: X11R5 (Xfree86), MGR.

        Editors: GNU Emacs, MicroEmacs, elvis, joe.

        Shells: Bash, zsh, tcsh, rc.

        Telecommunication: UUCP, kermit, szrz, minicom, pcomm, xcomm,
        term (runs multiple shells over one modem line).

        News and mail: C-news, trn, nn, tin, smail, elm.

        Textprocessing: TeX, groff.

        Games: Nethack, several Muds.

5. Getting Linux

   Anonymous FTP

        At least the following anonymous ftp sites carry Linux.  This
        list is taken from the Meta-FAQ list, which is posted every
        week to the comp.os.linux newsgroup (the Meta-FAQ is updated
        more often than this information sheet, so the list below may
        not be the most current one).

   textual name                            numeric addr    Linux directory

   tsx-11.mit.edu                          18.172.1.2      /pub/linux
   sunsite.unc.edu                         152.2.22.81     /pub/Linux
   nic.funet.fi                            128.214.6.100   /pub/OS/Linux
   ftp.mcc.ac.uk                           130.88.200.7    /pub/linux
   fgb1.fgb.mw.tu-muenchen.de              129.187.200.1   /pub/linux
   ftp.informatik.tu-muenchen.de           131.159.0.110   /pub/Linux
   ftp.dfv.rwth-aachen.de                  137.226.4.105   /pub/linux
   ftp.informatik.rwth-aachen.de           137.226.112.172 /pub/Linux
   kirk.bu.oz.au                           131.244.1.1     /pub/OS/Linux
   utsun.s.u-tokyo.ac.jp                   133.11.11.11    /misc/linux
   ftp.uu.net                              137.39.1.9      /packages/linux
   wuarchive.wustl.edu                     128.252.135.4   mirrors/linux
   ftp.win.tue.nl                          131.155.70.100  /pub/linux


    Other methods of obtaining Linux

        There are several BBS's that have Linux files.  A list of them
        is maintained by Zane Healy; he posts it to the comp.os.linux
        newsgroup around the beginning and middle of the month, please
        see that post for more information.

        There is also at least one organization that distributes Linux
        on floppies, for a fee.  Contact 

                Softlanding Software
                910 Lodge Ave.
                Victoria, B.C., Canada
                V8X-3A8
                (608) 360-0188

        The price is US$3.25 per disk ($4.00 Canadian) in 5.25" format
        (add $1/disk for 3.5").  Add GST (7%) and PST/SST as
        applicable, plus $10.00 for S&H (outside North America, add
        $10.00).  (Prices may change without notice.)  There are 13
        disk in a base system, 21 if you want X.

        Also, don't forget about friends and user's groups, who are
        usually glad to let you make a copy.

    Getting started

        As mentioned at the beginning, Linux is not centrally
        administered.  Because of this, there is no "official" release
        that one could point at, and say "That's Linux".  Instead,
        there are various "distributions", which are more or less
        complete collections of software configured and packaged so
        that they can be used to install a Linux system.  The two most
        important ones are the SLS and MCC releases.

        SLS is put together by Peter MacDonald, and is the more
        full-featured one.  It contains most of the available
        software, and includes X.  MCC is maintained by Owen LeBlanc
        at the Manchester Computing Centre, and has a longer history
        than SLS, but it doesn't contain X, and some other goodies.
        Either one serves as a starter's package.

        The first thing you should do is to get and read the list of
        Frequently Asked Questions (FAQ) from one of the FTP sites, or
        by using the normal Usenet FAQ archives (e.g.
        pit-manager.mit.edu).  This document has plenty of
        instructions on what to do to get started, what files you
        need, and how to solve most of the common problems (during
        installation or otherwise).

6. Legal Status of Linux

        Although Linux is supplied with the complete source code, it
        is copyrighted software, not public domain.  However, it is
        available for free under the GNU Public License.  See the GPL
        for more information.  The programs that run under Linux have
        each their own copyright, although much of it uses the GPL as
        well.  All of the software on the FTP site is freely
        distributable (or else it shouldn't be there).

7. News About Linux

        There is a Usenet newsgroup, comp.os.linux, for Linux
        discussion, and also several mailing lists.  See the Linux FAQ
        for more information about the mailing lists (you should be able
        to find the FAQ either in the newsgroup or on the FTP sites).

        The newsgroup comp.os.linux.announce is a moderated newsgroup
        for announcements about Linux (new programs, bug fixes, etc).

        For the current status of the Linux kernel, finger
        torvalds@kruuna.helsinki.fi.

        There is also a more or less weekly "newsletter", Linux News,
        which summarizes the most important announcements and uploads,
        and has occasional other articles as well.  Look in
        comp.os.linux for a sample issue.

8. Future Plans

        Work is underway on Linux version 1.0, which will close some
        of the gaps in the present implementation.  The major
        functionality shortcomings are advanced interprocess
        communication (semaphores, shared memory), closer
        compatibility with POSIX, and a lot of tweaking.
        Documentation is also sorely missing.

9. Legalese

        Trademarks are owned by their owners.  There is no warranty
        about the information in this document.

-- 
Send submissions for comp.os.linux.announce to: linux-announce@tc.cornell.edu

For pointers to more information, this is the META-FAQ for Linux:

Newsgroups: comp.os.linux.announce,comp.os.linux,news.groups
From: mdw@db.TC.Cornell.EDU (Matt Welsh)
Subject: Linux META-FAQ
Followup-To: poster
Keywords: linux faq
Organization: Cornell Theory Center
Date: Sat, 2 Jan 1993 03:55:08 GMT

Archive-name: linux-faq/meta-faq
Last-modified: 1 Jan 93

This is the Meta-FAQ for Linux.  It is mainly a list of valuable sources of
information.  Check them out if you want to learn more about Linux, or have
problems and need help.  The Meta-FAQ is posted every Monday (I think).
Mail Matt Welsh (mdw@tc.cornell.edu) if you have meta-questions about the
meta-FAQ itself. Lars Wirzenius (wirzeniu@cc.helsinki.fi) actually wrote the
first version of this document.

NOTE: Filenames in this article are for the tsx-11 ftp site (see below for
full address and more sites).  Files are usually located in similar places on
other sites.  The names are relative to the Linux directory on tsx-11.

What is Linux?
   Linux is a clone of the UNIX operating system that has been written
   entirely from scratch.  It has no proprietary code in it.  Linux is freely
   distributable under the GNU Public License.  It only works on IBM PC
   compatibles with an ISA or EISA bus and a 386 or compatible.  See the FAQ
   for more exact hardware requirements.  The Linux kernel is written by Linus
   Torvalds (torvalds@kruuna.helsinki.fi) from Finland.  Most of the programs
   running under Linux are generic Unix freeware, much of it comes from GNU.

The Linux FAQ 
   A collection of common problems and their solutions.  Answers many
   questions faster than the net.  Stored on many Linux ftp sites
   (docs/FAQ) and pit-manager.mit.edu, the general archive site for
   all FAQs.  The latest version was posted 1992-11-25.

Linux newsgroups
   There are two Usenet newsgroups for Linux: comp.os.linux, and
   comp.os.linux.announce.  The latter contains important stuff like
   announcements of new programs or versions, the former all the discussion.
   It is a good idea to follow at least c.o.l.a, if you use Linux.

Getting Linux I: Linux FTP sites
   textual name                            numeric addr    Linux directory

   tsx-11.mit.edu                          18.172.1.2      /pub/linux
   sunsite.unc.edu                         152.2.22.81     /pub/Linux
   nic.funet.fi                            128.214.6.100   /pub/OS/Linux
   ftp.mcc.ac.uk                           130.88.200.7    /pub/linux
   fgb1.fgb.mw.tu-muenchen.de              129.187.200.1   /pub/linux
   ftp.informatik.tu-muenchen.de           131.159.0.110   /pub/Linux
   ftp.dfv.rwth-aachen.de                  137.226.4.105   /pub/linux
   ftp.informatik.rwth-aachen.de           137.226.112.172 /pub/Linux
   kirk.bu.oz.au                           131.244.1.1     /pub/OS/Linux
   ftp.uu.net                              137.39.1.9      /packages/linux
   wuarchive.wustl.edu                     128.252.135.4   mirrors/linux
   ftp.win.tue.nl                          131.155.70.100  /pub/linux
   ftp.stack.urc.tue.nl                    131.155.2.71    /pub/linux
   srawgw.sra.co.jp                                        /Linux
        
   tsx-11 and fgb1 are the official sites for Linux' GCC.  ftp.mcc is home of
   the MCC interim release.  Some sites mirror other sites.  Please use the
   site closest (network-wise) to you.

Getting Linux II: Linux on BBS's
   Zane Healy posts (around the beginning and middle of the month) a list of
   BBS's that have Linux available for download.  Try them if you can't FTP.

Getting Linux III: Linux floppy (and other media) distributors
   Linux is distributed on floppies by at least Softlanding Software (910
   Lodge Ave, Victoria, B.C, Canada, V8X-3A8, (604) 360-0188) for USD
   3.25/disk.  This is exactly the same SLS distribution that is available via
   FTP (see below).  The diskette distribution is mostly meant for people who
   can't FTP.  

   Marco Scheibe (mykee@cs.tu-berlin.de), Klaus Weidner
   (klaus@snarc.gold.sub.org) and Gert Doering (gert@greenie.gold.sub.org)
   will copy Linux (the complete SLS distribution, including X, possibly other
   things as well) for you, if you send him diskettes and return postage.
   Contact them via e-mail first.

   Yggdrasil Computing is producing a CD-ROM with Linux.  Currently an alpha
   version is available (alpha referring to the fact that the contents are
   still evolving; there will be at least one beta before final release).
   This is a completely new distribution, not SLS.  A complete listing of
   files is available via FTP from netcom.com in directory ~ftp/pub/yggdrasil.
   There is also a manual and other information there.  Contact
   yggdrasil@netcom.com or call (510)526-7531, 9am-5:30pm, California time.

   If you know of other distributors, send me a note!

Getting Linux IV: Commercial networks
   GEnie mirrors most of tsx-11 and sunsite (including SLS).  Rumor has it
   that CompuServe also has some Linux archives [confirmation welcome].

Getting Linux V: Mailservers and such
   The trickle server TRICKLE@AWIWUW11.BITNET, aka TRICKLE@AWIWUW11.EARN, aka
   TRICKLE@AWIWUW11.wu-wien.ac.at, send mail to one of these addresses with a
   body consisting of /HELP.

Linux distributions (aka "releases")
   Linux is distributed by its author only as a kernel.  Other people
   have put together "distributions" that can be used.

   Jim Winstead and H.J. Lu maintain the boot and root disks.  These
   two form more or less the "official" release.  It is fully
   functional, but only has the bare essentials.  The filenames are:
   images/bootimage-xxx.Z and images/rootimage-xxx.Z (xxx stands for
   the version number). They're also hard to install for newcomers; I'd
   go for the SLS release (below) if you're new to Linux and want all of the
   goodies.

   MCC and SLS are more complete systems that contain most of what is needed
   for normal use.  MCC is older, SLS includes X.  These are what a new user
   probably should start with (either one).  They aren't updated every week,
   but that shouldn't be a problem if you're only intersted in using the
   system.  (Hackers will figure out what to do anyway.)  SLS is in directory
   packages/SLS on tsx-11; MCC can be found in directory mcc-interim on
   ftp.mcc.ac.uk (it is not on tsx-11).

   HJ Lu (the Linux GCC maintainer) also has another set of disks,
   including a combined boot and rootdisk, and some additional disks
   with more programs.  This package assumes you are already familiar
   with Linux, and at least some of it may be incorporated to the work
   of Jim Winstead.  See directories GCC/rootdisk and GCC/basedisk on
   tsx-11.

Linux mailing-lists
   Used mostly for discussion between developers of new features and testers
   of pre-release versions.  See addresses in the FAQ.

Linux News -- summaries of annoucements
   A weekly summary of announcements of new programs and other interesting
   news.  Edited by Denise Tree, posted to comp.os.linux.announce,
   comp.os.linux and the LINUXNEWS channel on the linux-activists mailing list
   (see the FAQ for info on joining mailing lists).  It is also available via
   GEnie.  Intended for people who don't have time or energy to sift through
   the high volume of comp.os.linux.

OTHER NEWSGROUPS ARE USEFUL TOO
   At least the groups comp.unix.{questions,shell,programming,bsd,admin}, and
   comp.windows.x.i386unix should be useful for a Linux user.  If you have a
   problem that is not directly Linux-related, ask it in these groups, not in
   c.o.l (which is too big for some people as it is).

Documentation for various programs
   Many programs come with some sort of documentation, often in a file called
   README or something similar.  It is a VERY good idea to read them with
   care.  It is boring to see (_and_ answer) questions that are answered in
   the documentation.

Keeping track of current releases
   New releases, programs, and ports are usually announced in comp.os.linux.
   finger torvalds@klaava.helsinki.fi to get some information about the
   current kernel (often long!).  See also the next item.

The Linux Project Registry
   Maintained by James Callison, a list of "who is doing what".  See the list
   itself for mail addresses.  Posted every two weeks to comp.os.linux.
   Contains information about the current status for included projects.

Legalese
   Trademarks are owned by their owners.  Satisfaction not guaranteed.
   No warranties about this document.

-- 
Matt Welsh     mdw@tc.cornell.edu     Cornell Theory Center
  "It's a Katana, ya Midwestern Computer Geek." --Tom Payne