<!doctype linuxdoc system>

<article>

<title>Linux Information Sheet
<author>Michael K. Johnson &lt;johnsonm@redhat.com&gt;
<date>v4.14, 1 September 1998
<abstract>
This document provides basic information about the Linux operating
system, including an explanation of Linux, a list of features, some
requirements, and some resources.
</abstract>

<toc>

<sect>Introduction to Linux

<p>Linux is a completely free reimplementation of the POSIX specification,
with SYSV and BSD extensions (which means it looks like Unix, but does
not come from the same source code base), which is available in both
source code and binary form.  Its copyright is owned by Linus Torvalds
&lt;torvalds@transmeta.com&gt; and other contributors, and is freely
redistributable under the terms of the GNU General Public License (GPL).
A copy of the GPL is included with the Linux source; you can also get a
copy from <url url="ftp://prep.ai.mit.edu/pub/gnu/COPYING">

<bf/Linux/, per se, is only the kernel of the operating system, the part
that controls hardware, manages files, separates processes, and so forth.
There are several combinations of Linux with sets of utilities and
applications to form a complete operating system.  Each of these
combinations is called a <bf/distribution/ of Linux.  The word <bf/Linux/,
though it in its strictest form refers specifically to the kernel, is
also widely and correctly to refer to an entire operating system built
around the Linux kernel.  For a list and brief discription of various
distributions, see
<url url="http://sunsite.unc.edu/LDP/HOWTO/Distribution-HOWTO.html">
<bf/None/ of these distributions is ``the official Linux''.

Linux is <bf/not/ public domain, nor is it `shareware'.  It is `free'
software, commonly called <bf/freeware/
or <bf/Open Source Software[tm]/ (see <url url="http://www.opensource.org">),
and you may give away or sell
copies, but you must include the source code or make it available in
the same way as any binaries you give or sell.  If you distribute any
modifications, you are legally bound to distribute the source for those
modifications.  See the GNU General Public License for details.

Linux is still free as of version 2.0, and will continue to be free.
Because of the nature of the GPL to which Linux is subject, it would be
illegal for it to be made not free.  Note carefully: the `free' part
involves access to the source code rather than money; it is perfectly
legal to charge money for distributing Linux, so long as you also
distribute the source code.  This is a generalization; if you want the
fine points, read the GPL.

Linux runs on 386/486/Pentium machines with ISA, EISA, PCI and VLB busses.
MCA (IBM's proprietary bus) is not well-supported in 2.0.x and earlier versions,
but support has been added to the current development tree, 2.1.x.
If you are interested, see <url url="http://glycerine.itsmm.uni.edu/mca">

There is a port to multiple Motorola 680x0 platforms
(currently running on some Amigas, Ataris, and VME machines), which
now works quite well.  It requires a 68020 with an MMU, a 68030, 68040,
or a 68060, and also requires an FPU. Networking and X now work.
See <url url="news:comp.os.linux.m68k">

Linux runs well on DEC's Alpha CPU, currently supporting the
"Jensen", "NoName", "Cabriolet", "Universal Desktop Box" (better
known as the Multia), and many other platforms.  For more
information, see <url url="http://www.azstarnet.com/~axplinux/FAQ.html">

Linux runs well on Sun SPARCs; most sun4c, sun4m, and sun4u machines now
run Linux, with support for sun4 in development.
Red Hat Linux is (as of this writing) the only
Linux distribution available for SPARCs; see
<url url="http://www.redhat.com/support/docs/rhl-sparc/">

Linux is being actively ported to the PowerPC architecture,
including PowerMac (Nubus and PCI), Motorola, IBM, and Be
machines.  See <url url="http://www.cs.nmt.edu/~linuxppc/"> and
<url url="http://www.linuxppc.org/">

Ports to other machines, including MIPS (see
<url url="http://linus.linux.sgi.com"> and <url url="http://lena.fnet.fr/">)
and ARM,
are under way and showing various amounts of progress.  Don't hold
your breath, but if you are interested and able to contribute, you may
well find other developers who wish to work with you.

Linux is no longer considered to be in beta testing, as version 1.0
was released on March 14, 1994.  There are still bugs in the system,
and new bugs will creep up and be fixed as time goes on.  Because
Linux follows the ``open development model'', all new versions will
be released to the public, whether or not they are considered
``production quality''.  However, in order to help people tell whether
they are getting a stable version or not, the following scheme has
been implemented:  Versions n.x.y, where x is an even number, are
stable versions, and only bug fixes will be applied as y is
incremented.  So from version 1.2.2 to 1.2.3, there were only bug
fixes, and no new features.  Versions n.x.y, where x is an odd number,
are beta-quality releases for developers only, and may be unstable and
may crash, and are having new features added to them all the time.
>From time to time, as the currect development kernel stabilizes, it
will be frozen as the new ``stable'' kernel, and development will
continue on a new development version of the kernel.  Note that most
releases of the Linux kernel, beta or not, are relatively robust;
``stable'' in this context means ``slow to change'' in addition
to ``robust''.

The current stable version is 2.0.35 (this will continue to change as
new device drivers get added and bugs fixed), and development has also
started on the experimental 2.1.x kernels.  The Linux kernel source code
contains a file, Documentation/Changes, which explains changes that
you should be aware of when upgrading from one kernel version to another.
However, the great majority of Linux users simply update their Linux
distribution occasionally to get a new kernel version.

Most versions of Linux, beta or not, are quite robust, and you
can keep using those if they do what you need and you don't
want to be on the bleeding edge.  One site had a computer
running version 0.97p1 (dating from the summer of
1992) for over 136 days without an error or crash.  (It would
have been longer if the backhoe operator hadn't mistaken a main
power transformer for a dumpster...) Others have posted uptimes
in excess of a year. One site still had a computer running
Linux 0.99p15s over 600 days at last report.

One thing to be aware of is that Linux is developed using an
open and distributed model, instead of a closed and
centralized model like much other software.  This means that
the current development version is always public (with up to a
week or two of 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, often in hours, as many people work to fix them.

In contrast, the closed and centralized 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.  The latest release of such software to the
public is sometimes of higher quality, but the development speed is
generally much slower.

For a discussion of these two models, read ``The Cathedral and the Bazaar''
at <url url="http://sagan.earthspace.net/~esr/writings/cathedral-bazaar/">
by Eric Raymond.

As of September 1, 1998, the current stable version of Linux is
2.0.35, and the latest development version is 2.1.119.

<sect>Linux Features

<p>
<itemize>
<item>multitasking: several programs running at the same time.
<item>multiuser: several users on the same machine at the same time
	(and <bf/no/ two-user licenses!).
<item>multiplatform: runs on many different CPUs, not just Intel.
<item>multiprocessor: SMP support is available on the Intel and
	SPARC platforms (with work currently in progress on other
	platforms), and Linux is used in several loosely-coupled MP
	applications, including Beowulf systems (see
	<url url="http://cesdis.gsfc.nasa.gov/linux-web/beowulf/beowulf.html">)
	and the Fujitsu AP1000+ SPARC-based supercomputer.
<item>multithreading: has native kernel support for multiple independent
	threads of control within a single process memory space.
<item>runs in protected mode on the 386.
<item>has memory protection between processes, so that one program can't
        bring the whole system down.
<item>demand loads executables: Linux only reads from disk those parts of a
        program that are actually used.
<item>shared copy-on-write pages among executables.  This means that
	multiple process can use the same memory to run in.  When one
	tries to write to that memory, that page (4KB piece of memory)
	is copied somewhere else.  Copy-on-write has two benefits:
	increasing speed and decreasing memory use.
<item>virtual memory using paging (not swapping whole processes) to
        disk: to a separate partition or a file in the filesystem, or
        both, with the possibility of adding more swapping areas during
        runtime (yes, they're still called swapping areas).  A total of 16
        of these 128 MB (2GB in recent kernels)
	swapping areas can be used at the same time, for a
	theoretical total of 2 GB of useable swap space.  It is simple
	to increase this if necessary, by changing a few lines of source code.
<item>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.
<item>dynamically linked shared libraries (DLL's), and static libraries
        too, of course.
<item>does core dumps for post-mortem analysis, allowing
	the use of a debugger on a program not only while it is running
	but also after it has crashed.
<item>mostly compatible with POSIX, System V, and BSD at the source
        level.
<item>through an iBCS2-compliant emulation module, mostly compatible with SCO,
	SVR3, and SVR4 at the binary level.
<item>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.  Plenty of
	commercial programs are being provided for Linux without
	source, but everything that has been free, including the
	entire base operating system, is still free.
<item>POSIX job control.
<item>pseudoterminals (pty's).
<item>387-emulation in the kernel so that programs don't need to
        do their own math emulation.  Every computer running Linux
        appears to have a math coprocessor.  Of course, if your
	computer already contains an FPU, it will be used instead
	of the emulation, and you can even compile your own kernel
	with math emulation removed, for a small memory gain.
<item>support for many national or customized keyboards, and it is
        fairly easy to add new ones dynamically.
<item>multiple virtual consoles: several independent login sessions
        through the console, you switch by pressing a hot-key
        combination (not dependent on video hardware).  These are
	dynamically allocated; you can use up to 64.
<item>Supports several common filesystems, including minix,
	Xenix, and all the common system V filesystems, and has an advanced
	filesystem of its own, which offers filesystems of up to 4 TB,
	and names up to 255 characters long.
<item>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).  MS-DOS 6 compressed
	partitions do not work at this time without a patch (dmsdosfs).
	VFAT (WNT, Windows 95) support and FAT-32 is available in Linux 2.0
<item>special filesystem called UMSDOS which allows Linux to be
	installed on a DOS filesystem.
<item>read-only HPFS-2 support for OS/2 2.1
<item>HFS (Macintosh) file system support is available separately as
	a module.
<item>CD-ROM filesystem which reads all standard formats of CD-ROMs.
<item>TCP/IP networking, including ftp, telnet, NFS, etc.
<item>Appletalk server
<item>Netware client and server
<item>Lan Manager/Windows Native (SMB) client and server
<item>Many networking protocols: the base protocols available in the
	latest development kernels include TCP, IPv4, IPv6, AX.25, X.25,
	IPX, DDP (Appletalk), Netrom, and others.  Stable network
	protocols included in the stable kernels currently include TCP, IPv4,
	IPX, DDP, and AX.25.
</itemize>


<sect>Hardware Issues

<sect1>Minimal configuration

<p>
The following is probably the smallest possible configuration that
Linux will work on: 386SX/16, 1 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.
See
<url url="http://rsphy1.anu.edu.au/~gpg109/mem.html"> for minimal
Linux configurations

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, unless your applications are quite limited.  It's
generally not recommended for anything but testing if things work, and
of course to be able to brag about small resource requirements.

<sect1>Usable configuration

<p>
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 will want 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 may still work with a smaller
amount of memory, but it will use virtual
memory (using the hard drive as <bf/slow/ memory) and that will be so
slow as to be unusable.  If you use many programs at the same time, 16 MB will
reduce swapping considerably.  If you don't want to swap appreciably
under normal load, 32 MB will probably suffice for a single user.
If you run lots of memory-intensive applications at once, 64 MB may
be necessary to avoid lots of swapping.  Of course, if
you run memory-hungry applications, you may want more.

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,
get Red Hat, Debian, or another distribution, and assume
that you will need 60 to 600 MB, depending on what you choose to install
and what distribution you get.  Add whatever space you want to
reserve for user files to these totals.  With today's prices on hard
drives, if you are buying a new system, it makes no sense to buy a
drive that is too small.  Get at least 2 GB, preferably 4 GB
or more, and you will not regret it.  Linux will happily handle
very large hard drive such as the recently popular 11 GB IDE hard
drives or 18 GB SCSI hard drives.

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.  In general, one big difference from DOS is
that with Linux, adding memory makes a large difference,
whereas with DOS, extra memory doesn't make that much
difference.  This of course has something to do with DOS's
640KB limit, which is completely nonexistent under Linux.

<sect1>Supported hardware

<p>
<descrip>
<tag/CPU:/ Anything that runs 386 protected mode programs.  All
models of 386s 486s, Pentiums, Pentium Pros, Pentium IIs,
and clones of these chips should work.  (286s and
below may someday be supported on a smaller kernel called ELKS
(Embeddable Linux Kernel Subset), but don't expect the same
capabilities).
A version for the 680x0 CPU (for
<em/x/ = 2 with external MMU, 3, 4, and 6) which runs on Amigas
and Ataris can be found at
tsx-11.mit.edu in the 680x0 directory.  Many DEC Alphas, SPARCs,
and PowerPC machines are supported.  Ports are also being
done to the ARM, StrongARM, and MIPS architectures.  More details
are available elsewhere.

<tag/Architecture:/ PCI, ISA, EISA, and VLB busses.  MCA (mostly true
blue PS/2s) support is incomplete but improving (see above).
Linux puts higher demands on hardware than DOS, Windows, and
in fact most operating systems.  This means that some marginal hardware
that doesn't fail when running less demanding operating system may fail
when running Linux.  Linux is an excellent memory tester...

<tag/RAM:/ Up to 1 GB on Intel; more on 64-bit platforms.
Some people (including Linus) have noted that adding ram
without adding more cache at the same time has slowed down
their machine extremely, so if you add memory and find your
machine slower, try adding more cache.  Some machines can
only cache certain amounts of memory regardless of how much
RAM is installed (64 MB is the most one popular chipset can
cache).  Over 64 MB of memory will require
a boot-time parameter with kernels 2.0.35 and earlier, as the
BIOS was originally designed to be unable to report more than
64MB.  Recent 2.1.x kernels and later are able to detect more
memory in a system.

<tag/Data storage:/ Generic AT drives (EIDE, IDE, 16 bit HD
controllers with MFM or RLL, or ESDI) are supported, as are
SCSI hard disks and CD-ROMs, with a supported SCSI adaptor.
Generic XT controllers (8 bit controllers with MFM or RLL) are
also supported.  Supported SCSI adaptors: Advansys, Adaptec 1542, 1522,
1740, 27xx, and 29xx (with some exceptions) series, Buslogic MultiMaster
and Flashpoint, NCR53c8xx-based
controllers, DPT controllers, Qlogic ISP and FAS controllers,
Seagate ST-01 and ST-02, Future Domain TMC-88x
series (or any board based on the TMC950 chip) and
TMC1660/1680, Ultrastor 14F, 24F and 34F, Western Digital
wd7000, and others.  SCSI, QIC-02, and some QIC-80 tapes are
also supported.  Besides IDE and SCSU cdroms, several proprietary
CD-ROM devices are also supported,
including Matsushita/Panasonic, Mitsumi, Sony, Soundblaster,
Toshiba, ATAPI (EIDE), SCSI, and others.  For exact models, check the hardware
compatibility HOWTO.  <bf/N.B./ These lists are incomplete, and
always will be.  Distribution vendors maintain more up-to-date lists.

<tag/Video:/ VGA, EGA, CGA, or Hercules (and compatibles) work
in text mode.  For graphics and X, there is support for (at
least) normal VGA, some super-VGA cards (most of the cards
based on Tseng, Paradise, and some Trident chipsets),
S3, 8514/A, ATI, Matrox, and Hercules.  (Linux uses
the XFree86 X server, so that determines what cards are
supported.  A full list of supported chipsets alone takes over
a page.  See <url url="http://www.XFree86.org/">)

<tag/Networking:/ 
Ethernet support includes 3COM 503/509/579/589/595/905 (501/505/507 are
supported but not recomended), AT&amp;T GIS (ne&eacute; NCR) WaveLAN, most
WD8390-based cards, most WD80x3-based cards, NE1000/2000 and most clones,
AC3200, Apricot 82596, AT1700, ATP, DE425/434/435/500, D-Link DE-600/620,
DEPCA, DE100/101, DE200/201/202 Turbo, DE210, DE422, Cabletron E2100
(not recommended), Intel EtherExpress (not recommended), EtherExpress Pro,
EtherExpress 100, DEC EtherWORKS
3, HP LAN, HP PCLAN/plus, most AMD LANCE-based cards, NI5210, ni6510,
SMC Ultra, DEC 21040 (tulip), Zenith Z-Note ethernet, All Zircom cards
and all Cabletron cards other than the E2100 are unsupported, due to
the manufacturers unwillingness to release programming information freely.

FDDI support currently includes the DEF<it>xx</it> cards from
DEC.

Point-to-Point networking support include PPP, SLIP, CSLIP, and PLIP.
PPP support is available for both standard asyncronous devices like
modems, and syncronous connections like ISDN.

Limited Token Ring support is available.

<tag/Serial:/ Most 16450 and 16550 UART-based boards, including
AST Fourport, the Usenet Serial Card II, and others.
Intelligent boards supported include Cyclades
Cyclom series (supported by the manufacturer), Comtrol
Rocketport series (supported by the manufacturer), Stallion
(most boards; supported by the manufacturer), and Digi (some
boards; supported by the manufacturer).  Some ISDN, frame
relay, and leased line hardware is supported.

<tag/Other hardware:/ SoundBlaster, ProAudio Spectrum 16,
Gravis Ultrasound, most other sound cards, most (all?)
flavours of bus mice (Microsoft, Logitech, PS/2), etc.
</descrip>

<sect>An Incomplete List of Ported Programs and Other Software

<p> Most of the common Unix tools and programs have been ported
to Linux, including almost all GNU software 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, because
Linux tracks POSIX quite closely.  There are never enough
applications for any operating system, but Linux is gaining
both end-user applications and server applications.
Contact the vendor of your favorite
commercial Unix application and ask if they have ported it to Linux.

Here is an incomplete list of
software that is known to work under Linux:

<descrip>
<tag/Basic Unix commands:/ <tt/ls/, <tt/tr/, <tt/sed/, <tt/awk/ and so
on (you name it, Linux probably has it).

<tag/Development tools:/ <tt/gcc/, <tt/gdb/, <tt/make/, <tt/bison/,
<tt/flex/, <tt/perl/, <tt/rcs/, <tt/cvs/, <tt/prof/.

<tag/Languages and Environments:/ C, C++, Objective C, Java, Modula-3,
Modula-2, Oberon, Ada95, Pascal, Fortran, ML, scheme, Tcl/tk, Perl, Python,
Common Lisp, and many others.

<tag/Graphical environments:/ GNOME and KDE (desktops),
X11R6 (XFree86 3.x),
X11R5 (XFree86 2.x), MGR.

<tag/Editors:/ GNU Emacs, XEmacs, MicroEmacs, <tt/jove/, ez,
<tt/epoch/, <tt/elvis/ (GNU vi), <tt/vim/, <tt/vile/, <tt/joe/,
<tt/pico/, <tt/jed/, and others.

<tag/Shells:/ <tt/bash/ (POSIX sh-compatible), <tt/zsh/ (includes <tt/ksh/
compatiblity mode), <tt/pdksh/, <tt/tcsh/, <tt/csh/, <tt/rc/,
<tt/es/, <tt/ash/
(mostly sh-compatible shell used as <tt>/bin/sh</tt> by BSD), and
many more.

<tag/Telecommunication:/ PPP, UUCP, SLIP, CSLIP, full TCP/IP
communication toolset,
<tt/kermit/, <tt/szrz/, <tt/minicom/, <tt/pcomm/,
<tt/xcomm/, <tt/term/ (runs multiple shells, redirects network
activity, and allows remote X, all over one modem line), Seyon
(popular X-windows communications program), and several fax and
voice-mail (using ZyXEL and other modems) packages are
available.  Of course, remote serial and network logins are supported.

<tag/News and mail:/ C-news, <tt/innd/, <tt/trn/, <tt/nn/, <tt/tin/,
<tt/smail/, <tt/elm/, <tt/mh/, <tt/exmh/, <tt/pine/, <tt/mutt/, etc.

<tag/Textprocessing:/ TeX, <tt/groff/, <tt/doc/, <tt/ez/, LyX, Lout,
Linuxdoc-SGML, and others.

<tag/Games:/ Nethack, several Muds and X games, and lots of
others.  One of those games is looking through all the games available
at tsx-11 and sunsite.
</descrip>

All of these programs (and this isn't even a hundredth of what
is available) are freely available.  Commercial software is
becoming widely available; ask the vendor of your favorite
commercial software if they support Linux.

<sect>Who uses Linux?

<p>
Linux is freely available, and no one is required to register their
copies with any central authority, so it is difficult to know how many
people use Linux.  Several businesses now survive solely on
selling and supporting Linux, and the Linux newsgroups are some
of the most heavily read on the internet, so the number is likely in
the millions, but firm numbers are hard to come by.  The best
market research currently indicates between 7.5 and 11 million
users.

<p>One brave soul, Harald T. Alvestrand
&lt;Harald.T.Alvestrand@uninett.no&gt;, has decided to try to count
Linux users the hard way: one by one.  If you
are willing to be counted as a Linux user, please use the web forms
available at <url url="http://counter.li.org/"> Alternatively, you can
send a message to linux-counter@uninett.no with one of the following
subjects: `I use Linux at home', `I use Linux at work', or `I use Linux
at home and at work'.  He will also accept `third-party' registrations;
ask him for details.

<p>He posts his counts to <url url="news:comp.os.linux.misc"> each month;
they are also available from <url url="http://counter.li.org/">.

<sect>Getting Linux

<sect1>Anonymous FTP

<p>
For freely-redistributable Linux documentation, see the Linux
Documentation Project sites at
<url url="ftp://sunsite.unc.edu/pub/Linux/docs/LDP/"> and
<url url="http://sunsite.unc.edu/LDP/">

<p>Stay tuned to the
<url url="news:comp.os.linux.announce"> newsgroup for further developments.

At least the following anonymous ftp sites carry Linux.

<tscreen><verb>
Textual name                   Numeric address  Linux directory
=============================  ===============  ===============
tsx-11.mit.edu                 18.172.1.2       /pub/linux
sunsite.unc.edu                152.2.22.81      /pub/Linux
ftp.funet.fi                   128.214.248.6    /pub/Linux
net.tamu.edu                   128.194.177.1    /pub/linux
ftp.mcc.ac.uk                  130.88.203.12    /pub/linux
src.doc.ic.ac.uk               146.169.2.1      /packages/linux
fgb1.fgb.mw.tu-muenchen.de     129.187.200.1    /pub/linux
ftp.informatik.tu-muenchen.de  131.159.0.110    /pub/comp/os/linux
ftp.dfv.rwth-aachen.de         137.226.4.111    /pub/linux
ftp.informatik.rwth-aachen.de  137.226.225.3    /pub/Linux
ftp.Germany.EU.net             192.76.144.75    /pub/os/Linux
ftp.lip6.fr                    132.227.77.2     /pub/linux
ftp.uu.net                     137.39.1.9       /systems/unix/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               133.137.4.3      /pub/os/linux
cair.kaist.ac.kr                                /pub/Linux
ftp.denet.dk                   129.142.6.74     /pub/OS/linux
NCTUCCCA.edu.tw                140.111.1.10     /Operating-Systems/Linux
nic.switch.ch                  130.59.1.40      /mirror/linux
sunsite.cnlab-switch.ch        193.5.24.1       /mirror/linux
cnuce_arch.cnr.it              131.114.1.10     /pub/Linux
ftp.monash.edu.au              130.194.11.8     /pub/linux
ftp.dstc.edu.au                130.102.181.31   /pub/linux
ftp.sydutech.usyd.edu.au       129.78.192.2     /pub/linux
</verb></tscreen>

<p>
tsx-11.mit.edu and fgb1.fgb.mw.tu-muenchen.de are the official sites
for Linux's GCC.  Some sites mirror other sites.  Please use the site
closest (network-wise) to you whenever possible.

At least sunsite.unc.edu and ftp.informatik.tu-muenchen.de offer
ftpmail services.  Mail ftpmail@sunsite.unc.edu or
ftp@informatik.tu-muenchen.de for help.

If you are lost, try looking at
<url url="http://sunsite.unc.edu/LDP/HOWTO/Distribution-HOWTO.html">,
where several distributions are enumerated.  Red Hat Linux and Debian
appear to be the most popular distributions at the moment, at
least in the U.S.

<sect1>CDROM

<p>
Most people now install Linux from CDROM's.  The distributions
have grown to hundreds of MBs of Linux software, and downloading
that over even a 28.8 modem or an ISDN connection takes a
<bf>long</bf> time.

<p>
There are essentially two ways to purchase a Linux distribution
on CDROM: as part of an archive of FTP sites, or directly from
the manufacturer.  If you purchase an archive, you will often
get several different distributions to choose from, but
support is generally not included.  When you purchase a
distribution directly from the vendor, you usually only get one
distribution, but you usually get some form of support, usually
installation support.

<sect1>Other methods of obtaining Linux

<p>
There are many BBSs that have Linux files.  A list of them
is occasionally posted to comp.os.linux.announce.  Ask friends and
user groups, or order one of the commmercial distributions.  A list of
these is contained in the Linux distribution HOWTO, available as
<url url="http://sunsite.unc.edu/LDP/HOWTO/Distribution-HOWTO.html">,
and posted regularily to the <url url="news:comp.os.linux.announce"> newsgroup.


<sect>Legal Status of Linux

<p> 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 General Public License, sometimes
referred to as the ``copyleft''.  See the GPL for more
information.  The programs that run under Linux each have their
own copyright, although many of them use the GPL as well.  X
uses the MIT X copyright, and some utilities are under the BSD
copyright.  In any case, all of the software on the FTP site is
freely distributable (or else it shouldn't be there).

<sect>News About Linux

<p> A monthly magazine, called <em/Linux Journal/, was launched over
four years ago.  It includes articles intended for almost all skill
levels, and is intended to be helpful to all Linux users.
One-year subscriptions are &dollar;22 in the U.S., &dollar;27
in Canada and Mexico, and &dollar;32 elsewhere, payable in US
currency.  Subscription inquiries can be sent via email to
subs@ssc.com, or faxed to +1-206-782-7191, or phoned to
+1-206-782-7733, or mailed to Linux Journal, PO Box 85867,
Seattle, WA 98145-1867 USA.  SSC has a PGP public key available
for encrypting your mail to protect your credit card number;
finger info@ssc.com to get the key.

There are several Usenet newsgroups 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 <url url="news:comp.os.linux.announce"> is a moderated newsgroup
for announcements about Linux (new programs, bug fixes, etc).

The newsgroup <url url="news:comp.os.linux.answers"> is a moderated newsgroup to
which the Linux FAQ, HOWTO documents, and other documentation
postings are made.

The newsgroup <url url="news:comp.os.linux.admin"> is an unmoderated newsgroup for
discussion of administration of Linux systems.

The newsgroup <url url="news:comp.os.linux.development.system"> is an unmoderated newsgroup
specifically for discussion of Linux <bf/kernel/ development.  The
only application development questions that should be discussed here
are those that are intimately associated with the kernel.  All other
development questions are probably generic Unix development questions
and should be directed to a comp.unix group instead, unless
they are very Linux-specific applications questions, in which
case they should be directed at comp.os.linux.development.apps.

The newsgroup <url url="news:comp.os.linux.development.apps"> is an unmoderated
newsgroup specifically for discussion of Linux-related
applications development.  It is not for discussion of where to
get applications for Linux, nor a discussion forum for those
who would like to see applications for Linux.

The newsgroup <url url="news:comp.os.linux.hardware"> is for Linux-specific
hardware questions.

The newsgroup <url url="news:comp.os.linux.networking"> is for Linux-specific
networking development and setup questions.

The newsgroup <url url="news:comp.os.linux.x"> is for Linux-specific X Windows
questions.

The newsgroup <url url="news:comp.os.linux.misc"> is the replacement for comp.os.linux,
and is meant for any discussion that doesn't belong elsewhere.

In general, <bf/do not/ crosspost between the Linux newsgroups.
The <bf/only/ crossposting that is appropriate is an occasional posting
between one unmoderated group and <url url="news:comp.os.linux.announce">.
The whole point of splitting the old comp.os.linux group into many groups
is to reduce traffic in each group.  Those that do not follow this rule
will be flamed without mercy...

Linux is on the web at the URL
<url url="http://sunsite.unc.edu/LDP/">

<sect>The Future

<p> After Linux 1.0 was released, work was done on several
enhancements.  Linux 1.2 included disk access speedups, TTY improvements,
virtual memory enhancements, multiple platform
support, quotas, and more.  Linux 2.0, the current stable version, has
even more enhancements, including many performance
improvements, several new networking protocols, one of the
fastest TCP/IP implementations in the world, and far, far more.
Even higher performance, more networking protocols, and more device
drivers will be available in Linux 2.2.

Even with over 3/4 million lines of code in the kernel,
there is plenty of code left to write, and even more documentation.
Please join the linux-doc@vger.rutgers.edu mailing list if you would
like to contribute to the documentation. Send mail to
majordomo@vger.rutgers.edu with a single line containing the word
``help'' in the body (<bf/NOT/ the subject) of the message.

<sect>This document

<p>
This document is maintained by Michael K. Johnson
&lt;johnsonm@redhat.com&gt;. Please mail me with any comments, no matter
how small.  I can't do a good job of maintaining this document without
your help.  A more-or-less current copy of this document can always be
found at
<url url="http://sunsite.unc.edu/LDP/">

<sect>Legalese

<p>
Trademarks are owned by their owners.  There is no warranty
about the information in this document.  Use and distribute at your
own risk.  The content of this document is in the public domain, but
please be polite and attribute any quotes.

</article>
