Boot Disc 15/boot-disc-1997-11.iso/Debian/Docs/debian-faq.txt

Text File | 1997-09-15 | 123KB | 2,778 lines

                          The Debian GNU/Linux FAQ

 Susan G. Kleinmann ([e-mail]), Sven Rudolph ([e-mail]),
                  and Joost Witteveen ([e-mail])

                              28 December 1996


1.  Meta-questions


1.1.  In what format is this document written?

This document was written using the Linuxdoc-SGML DTD.  The
Linuxdoc-SGML system can be used to create files in a variety of other
formats, e.g., GNU info, HTML, LaTeX, TeX .dvi format, and PostScript
(TM) files.  sdc (SGML Document Compiler) is an alternative system
that in some cases produces better output than
Linuxdoc-SGML. Linuxdoc-SGML and sdc are available as Debian packages.


1.2.  Where do I get the latest version of this document?

The latest version of this document can be viewed in HTML format at
the Debian home page ( http://www.debian.org/FAQ/ ) .

It is also available in HTML, PostScript, GNU info and plain text
format at the Debian FTP Server ( ftp://ftp.debian.org/debian/ ) and
any of its mirrors ( http://www.debian.org/ftplist.html ) in the
directory doc/FAQ/.

The original SGML files used to create this document are available as
part of the Debian package called doc-debian_VVV-RRR.deb, where VVV is
the latest version number and RRR is the latest revision number. This
package is normally stored in the directory stable/binary-all/doc/.
The linuxdoc-sgml package contains tools to transform this document
into one or more other formats, as required by the user: GNU info
files, HTML, LaTeX, TeX .dvi format, and PostScript.


1.3.  Where do I send questions, corrections, etc. about this document?

Comments on this document are welcome.  Please send e-mail to
[e-mail].


1.4.  (How) Can I redistribute this file?

This document is copyright 1996 by SPI (see section Software in the
Public Interest (14.3.1)).

Permission is granted to make and distribute verbatim copies of this
document provided the copyright notice and this permission notice are
preserved on all copies.

Permission is granted to copy and distribute modified versions of this
document under the conditions for verbatim copying, provided that the
entire resulting derived work is distributed under the terms of a
permission notice identical to this one.

Permission is granted to copy and distribute translations of this
document into another language, under the above conditions for
modified versions, except that this permission notice may be included
in translations approved by the Free Software Foundation instead of in
the original English.


1.5.  What information resources were used to obtain the questions and
      answers presented here?

This FAQ previously was maintained by J.H.M.  Dassen
([e-mail]) and Chuck Stickelman ([e-mail]).

Parts of the information came from
o  The Debian-1.1 release announcement (
   http://www.debian.org/1.1/release.html ) by Bruce Perens.
o  The  Linux FAQ (  http://www.cl.cam.ac.uk/users/iwj10/linux-faq/ ) by
   Ian Jackson ( http://www.cl.cam.ac.uk/users/iwj10/ijackson.html ) .
o  The  Debian Mailing List Archives (
   ftp://ftp.debian.org/debian/debian-lists/ )
o  The dpkg programmers' manual and the Debian policy manual (12.1)
o  The many developers, volunteers, and beta testers.
o  The flaky memories of its authors.

The authors would like to thank all those who helped make this
document possible.



2.  Definitions and Overview


2.1.  What is Debian GNU/Linux?

Debian GNU/Linux is a particular distribution of the Linux operating
system, and numerous packages that run on it. In principle, users
could obtain the Linux kernel via the Internet or from elsewhere, and
compile it themselves.  They could then obtain source code for many
applications in the same way, compile the programs, then install them
into their systems.  For complicated programs, this process can be not
only time-consuming but error-prone.  To avoid it, users often choose
to obtain the operating system and the application packages from one
of the Linux distributors.  What distinguishes the various Linux
distributors are the software, protocols, and practices they use for
packaging, installing, and tracking applications packages on users'
systems, combined with installation and maintenance tools,
documentation, and other services.

Debian GNU/Linux is the result of a volunteer effort to create a free,
high-quality Unix-compatible operating system, complete with a suite
of applications.  The idea of a free Unix-like system originates from
the GNU project, and many of the applications that make Debian
GNU/Linux so useful were developed by the GNU project.

Debian was created by Ian Murdock in 1993, initially under the
sponsorship of the Free Software Foundation's GNU project.  Today,
Debian's developers think of it as a direct descendent of the GNU
project.

Debian GNU/Linux is
o  full featured: Debian includes more than 700 software packages at
   present.  Users can select which packages to install;  Debian provides
   a  tool for this purpose.  You can find a list and descriptions of the
   packages currently available in Debian at any of the Debian mirror
   sites.
o  free to use and redistribute:  There is no consortium membership or
   payment required to participate in its distribution and development.
   All packages that are formally part of Debian GNU/Linux are free to
   redistribute, usually under terms specified by the GNU General Public
   License.  The Debian FTP archives also carry approximately 50 software
   packages (in the  non-free and contrib directories at the FTP archives),
   which are distributable under specific terms included with each
   package.
o  dynamic: With about 120 volunteers constantly contributing new and
   improved code, Debian is evolving rapidly.  New releases are planed
   to be made about every three months, and the FTP archives are updated
   daily.

Though Debian itself is free software, it is a base upon which
value-added Linux distributions can be built.  By providing a
reliable, full-featured base system, Debian provides Linux users with
increased compatibility, and allows Linux distribution creators to
eliminate duplication-of-effort and focus on the things that make
their distribution special.


2.2.  OK, now I know what Debian is...what is Linux!?

In short, Linux is the kernel of a Unix-like operating system.  It was
originally designed for 386/486/Pentium PCs; now, ports to other
systems, including multi-processor systems, are under
development. Linux is written by Linus Torvalds and many computer
scientists around the world.

Besides its kernel, a Linux system usually has:
o  a file system that follows the Linux Filesystem Hierarchy Standard
   ( http://www.pathname.com/fhs/ ) .
o  a wide range of Unix utilities, many of which have been developed by
   the GNU project and the Free Software Foundation.

The combination of the Linux kernel, the filesystem, the GNU and FSF
utilities, and the other utilities are designed to achieve compliance
with the POSIX (IEEE 1003.1) standard; see source code compatibility
(4.2).

For more information about Linux, see Michael K. Johnson's INFO-SHEET
( ftp://sunsite.unc.edu/pub/Linux/docs/HOWTO/INFO-SHEET ) and META-FAQ
( ftp://sunsite.unc.edu/pub/Linux/docs/HOWTO/META-FAQ ) .


2.3.  What is the difference between Debian and other Linux distributions?

Three key features distinguish Debian from other Linux distributions:

The Debian package maintenance system: The entire system, or
   any individual component of it, can be upgraded in place without
   reformatting, without losing custom configuration files, and (in
   most cases) without rebooting the system.  Most Linux distributions
   available today have some kind of package maintenance system; the
   Debian package maintenance system (6) is unique and particularly
   robust.

Open development: Whereas other Linux distributions are developed by
   individuals, small, closed groups, or commercial vendors, Debian is
   the only Linux distribution that is being developed cooperatively
   by many individuals through the Internet, in the same spirit as
   Linux and other free software. More than 120 volunteer package
   maintainers are working on over 700 packages and improving Debian
   GNU/Linux.  The Debian developers contribute to the project not by
   writing new applications (in most cases), but by packaging existing
   software according to the standards of the project, by
   communicating bug reports to upstream developers, and by providing
   user support.  See also additional information on how to become a
   contributor (14.1).

The Bug Tracking System: The geographical dispersion of the Debian
   developers required sophisticated tools and quick communication of
   bugs and bug-fixes to accelerate the development of the system.
   Users are encouraged to send bugs in a formal style, which are
   quickly accessible by WWW archives or via e-mail. See additional
   information in this FAQ on the management of the Bug Log (13).

2.4.  How does the Debian project fit in or compare with the Free Software
      Foundation's GNU project?

The Debian system builds on the ideals of free software first
championed by the Free Software Foundation (
http://www.gnu.ai.mit.edu/ ) and in particular by Richard Stallman.
FSF's powerful system development tools, utilities, and applications
are also a key part of the Debian system.

The Debian Project is a separate entity from the FSF, however we
communicate regularly and cooperate on various projects. The FSF
explicitly requested that we call our system "Debian GNU/Linux", and
we are happy to comply with that request.

The FSF's long-standing objective is to develop a new operating system
called GNU based on HURD
( http://www.gnu.ai.mit.edu/software/hurd/hurd.html ).


2.5.  How does one pronounce Debian and what does this word mean?

The project name is pronounced Deb'-ian, with a short e, and emphasis
on the first syllable.  This word is a contraction of the names of
Debra and Ian Murdock, who founded the project.  (Dictionaries seem to
offer some ambiguity in the pronunciation of Ian (!), but Ian prefers
ee'-an.)


3.  Hardware Requirements



3.1.  On what architectures/systems does Debian GNU/Linux run?

Debian GNU/Linux includes complete source-code for all of the included
programs, so it should work on all systems which are supported by the
Linux Kernel; see the Linux FAQ (
http://www.cl.cam.ac.uk/users/iwj10/linux-faq/ ) for details.

The current Debian GNU/Linux release contains a complete, binary
distribution for the i386 architecture; this covers PCs based on
Intel-compatible processors, including Intel's80386, 80486, Pentium,
and Pentium Pro, and compatible processors by AMD, Cyrix and others.
The development of binary distributions of Debian 1.2 for the m68k
architecture (Motorola 680x0 processors for x>=2; with MMU) is
currently underway, and ports to Alpha, SPARC, and MIPS processors are
expected to follow.


3.2.  What hardware is assumed by the stock Debian GNU/Linux boot disks?

The configuration file used to build Debian GNU/Linux' standard
distribution kernel assumes an 80386 CPU, and includes support for
PCMCIA cards SCSI cards for which there exist Linux drivers. Support
for network interface card is provided by loadable modules, so there
is no need to compile these drivers into the kernel.


3.3.  What amount of disk space is recommended?

A generous installation, sufficient to accommodate a few users, X
Window System software, and several large applications, might require
disk partitions at least as large as:
o  50 MBytes for the root directory (/)
o  500 MBytes for /usr
o  50 MBytes for swap space
o  50 MBytes for each home directories
o  100 MBytes for /tmp
o  100 MBytes for /var

The optimum disk space allocated for swap depends critically on the
way the system will be used.  Many people just choose to set aside
twice as much disk space as they have RAM space.  Systems with large
RAM may not need so much swap space, especially if there are only a
few users. The installation process supports systems with no swap
space.


3.3.1 But how much RAM and disk space are absolutely essential?

These minimal requirements are sufficient for a system without X11 and
only 1 or 2 users:

o  15 MBytes of disk space for the base system; this provides a
   minimally-functioning Unix system, but includes no application
   programs and no network support.
o  100 MBytes of disk space for a standard system running applications
   on the console (i.e., without an X11 interface).
o  150 MBytes of disk space for a standard system running applications
   with the X Window System.
o  300 MBytes and more for all the optional programs (You probably do
   not need all of these programs.)

Debian Linux can be installed on systems with only 4 MBytes of
RAM. The latest installation disks are especially organized to provide
an easy installation path for machines with small memories.  Some
users report success at using Debian Linux to convert PCs having
limited RAM (and disk space) into X terminals.  An 80386-based system
with only 4 MBytes of RAM and 40 MBytes disk space has been used to
run Debian Linux in this way; i.e., both networking and basic X11
server functions operated satisfactorily. This mode of operation even
works if 1 MByte of the RAM is used as a ramdisk when the machine is
booted, implying that only 3 Mbytes of RAM is absolutely essential for
using Debian Linux on a PC in order to use it as an X server.  This
mode of operation requires a swap partition; without it, the system
will not even go into multi-user mode.


3.4.  How should I partition my drive?

Partitioning a drive has the disadvantage that drive space can be used
much less flexibly than an unpartitioned drive.  Most users find,
however, that this disadvantage is more than offset by the fact that
damage to a filesystem on a partitioned disk is usually limited to a
single partition.  Furthermore, backups of a partitioned hard disk can
be more easily managed because the files that change most frequently
are likely to be localized to a single partition.

A user with a 1.6 GByte drive has concluded after a survey of Debian
users that it is reasonable to design a partitioning scheme that
closely follows the Filesystem Hierarchy Standard (
http://www.pathname.com/fhs/ ) . For his 1.6 GByte disk, he chose
these partitions:

o  30 MBytes for the root directory (/)
o  450 MBytes for /usr
o  50 MBytes for swap space
o  1000 MBytes for home directories (some of this could be used for
   /usr/local/)
o  0 MBytes for /tmp; make /tmp a symbolic link to /var/tmp
o  40 MBytes for /var

It is possible to use a swap file instead of a swap partition. However
this usually is a bad solution, so we suggest to use a swap partition.


3.5.  Are very large disks supported?

There is an upper limit on the size of the disk partition that is used
for booting.  This limit applies to all operating systems, not just
Linux. Basically, the BIOSs typically available on PCs cannot access
disk partitions larger than 1024 cylinders or tracks. Thus, any
operating system used on a PC cannot be booted from a disk partition
larger than 1 GByte.  It is worth emphasizing that this restriction
only applies to the partition from which Linux is booted. Other
partitions can be larger.  One solution to this limitation is to place
the directory /boot/ (and usually the whole root partition) in its own
(very small) partition, entirely within the first 1024 blocks of the
disk.

Support for large non-bootable partitions varies with the
driver. Detailed information is provided in the Large-Disk mini-HOWTO.

The Linux kernel includes the Multi-Device disk driver ('md'), which
provides plain concatenation of drives (called linear mode) or
striping support (also known as RAID 0) in software.


3.6.  (How) Does Debian provide PCMCIA support?

Utilities that provide PCMCIA card services have been developed by
David Hinds.  These utilities are provided in Debian by the package
pcmcia-cs-KKK_VVV-RRR.deb, where the components 'VVV' and 'RRR' follow
the usual conventions on Debian package names (6.3), and the component
'KKK' refers to the kernel version for which the pcmcia-cs package was
built.

The   pcmcia-modules-KKK  package   must   be  rebuilt   for  systems   not
using   the   default   Debian   kernel.    The   pcmcia-source_VVV-RRR.deb
package  is   provided  for  users   who  need  to  recompile   the  PCMCIA
modules  or  utilities.   It  unpacks  the  source  files  for  the  PCMCIA
utilities   into  the   /usr/src/modules/pcmcia-cs/  directory.    See  the
/usr/src/modules/pcmcia-cs/README.gz  file;  it contains  instructions  for
rebuilding the PCMCIA packages.

PCMCIA cards that include IDE drives have to be supported by the
kernel.  The version of the kernel distributed with the Debian
installation disks includes support for such PCMCIA cards.  That is,
its .config file includes the line: CONFIG_BLK_DEV_IDE_PCMCIA=y.



4.  Compatibility issues


4.1.  How compatible is Debian with other distributions of Linux?

Debian developers communicate with other Linux distribution creators
in an effort to maintain binary compatibility across Linux
distributions. Most commercial Linux products run as well under Debian
as they do on the system upon which they were built.

Debian GNU/Linux adheres strictly to the Linux File System Structure (
http://www.pathname.com/fhs/ ) (now known as the FHS). However, there
is room for interpretation in some of the rules within this standard,
so there may be differences between a Debian system and other Linux
systems.


4.2.  How source code compatible is Debian with other Unix systems?

For most applications Linux source code is compatible with other Unix
systems.  It supports almost everything that is available in System V
Unix systems and the free and commercial BSD- derived systems. However
in the Unix business such claim has nearly no value because there is
no way to prove it. In the software development area complete
compatibility is required instead of compatibility in about most
cases. So years ago the need for standards arose, and nowadays POSIX.1
(IEEE Standard 1003.1-1990) is one of the major standards for source
code compatibility in Unix-like operating systems.

Linux is intended to adhere to POSIX.1, but the POSIX standards cost
real money and the POSIX.1 (and FIPS 151-2) certification is quite
expensive; this made it more difficult for the Linux developers to
work on complete POSIX conformance.  The certification costs make it
unlikely that Debian will get an official conformance certification
even if it completely passed the validation suite. (The validation
suite is now freely available, so it is expected that more people will
work on POSIX.1 issues.)

Unifix GmbH (Braunschweig, Germany) developed a Linux system that has
been certified to conform to FIPS 151-2 (a superset of POSIX.1). This
technology is available in Unifix' own distribution called Unifix
Linux 2.0 and in Lasermoon's Linux-FT (
http://www.lasermoon.co.uk/linux-ft/linux-ft.html ) . Currently Unifix
merges its patches into the Linux kernel, gcc and other tools; so it
is expected that their fixes towards POSIX.1 conformance will be
available in Debian (and other distributions).


4.3.  Can I use Debian packages (.deb files) on my RedHat/Slackware/...
      Linux system? Can I use RedHat packages (.rpm files) on my Debian
      GNU/Linux system?

Different Linux distributions use different package formats and
different package management programs.


You probably can: A program to unpack a Debian package onto a Linux
   host that is been built from a `foreign' distribution is available,
   and will generally work, in the sense that files will be unpacked.
   The converse is probably also true, that is, a program to unpack a
   RedHat or Slackware package on a host that is based on Debian Linux
   will probably succeed in unpacking the package and placing most
   files in their intended directories.  This is largely a consequence
   of the existence (and broad adherence to) the Linux File System
   Standard.

You probably do not want to: Most package managers write
   administrative files when they are used to unpack an archive.
   These administrative files are generally not standardized.
   Therefore, the effect of unpacking a Debian package on a `foreign'
   host will have unpredictable (certainly not useful) effects on the
   package manager on that system.  Likewise, utilities from other
   distributions might succeed in unpacking their archives on Debian
   systems, but will probably cause the Debian package management
   system to fail when the time comes to upgrade or remove some
   packages, or even simply to report exactly what packages are
   present on a system.

A better way: The Linux File System Standard (and therefore Debian
   GNU/Linux) requires that subdirectories under /usr/local/ be
   entirely under the user's discretion.  Therefore, users can unpack
   `foreign' packages into this directory, and then manage their
   configuration, upgrade and removal individually.


4.4.  Is Debian able to run my old a.out programs?

To execute a program whose binary is in a.out (i.e., QMAGIC or ZMAGIC)
format,

o  Make sure your kernel has a.out support built into it, either
   directly (CONFIG_BINFMT_AOUT=y) or as a module
   (CONFIG_BINFMT_AOUT=m). (Debian's kernel-image package contains the
   module binfmt_aout.)

   If your kernel supports a.out binaries by a module, then be sure
   that the binfmt_aout module is loaded.  You can do this at boot
   time by entering the line binfmt_aout into the file /etc/modules.
   You can do it from the command line by executing the command insmod
   DIRNAME/binfmt_aout.o where DIRNAME is the name of the directory
   where the modules that have been built for the version of the
   kernel now running are stored. On a system with the 2.0.27 version
   of the kernel, DIRNAME is likely to be /lib/modules/2.0.27/fs/.
o  install the package libc4.
o  If the program you want to execute is an a.out X client, then
   install the xcompat package.

If you have a commercial application in a.out format, now would be a
good time to ask them to send you an ELF upgrade.


4.5.  Can Debian be used to compile a.out programs?

To compile programs in the a.out binary format,

o  install the Debian a.out developer's packages, which are
   -  libc4-dev
   -  aout-binutils

   -  aout-librl
   -  aout-gcc

o  place the a.out tools ahead of the ELF tools in your path.  That is,
   execute the command export PATH=/usr/i486-linuxaout/bin:$PATH (This
   is not essential, just advantageous.) If you are only going to do
   this once, you could execute: PATH=/usr/i486-linuxaout/bin:$PATH
   make target.


4.6.  How should I install a non-Debian package?

Files under the directory /usr/local/ are not under the control of the
Debian package management system.  Therefore, it is good practice to
place the source code for your program in /usr/local/src/.  For
example, you might extract the files for a package named foo.tar into
the directory /usr/local/src/foo.  After you compile them, place the
binaries in /usr/local/bin/, the libraries in /usr/local/lib/, and the
configuration files in /usr/local/etc/.

If your programs and/or files really must be placed in some other
directory, you could still store them in /usr/local/, and build the
appropriate symbolic links from the required location to its location
in /usr/local/, e.g., you could make the link

ln -s /usr/local/bin/foo /usr/bin/foo

In any case, if you obtain a package whose copyright allows
redistribution, you should consider making a Debian package of it, and
uploading it for the Debian system.  Guidelines for becoming a package
developer are included in the Debian policy manual (12.1).


4.7.  Why can't I compile programs that require libtermcap?

Debian uses the terminfo database and the ncurses library of terminal
interface routes, rather than the termcap database and the termcap
library.  Users who are compiling programs that require some knowledge
of the terminal interface should replace references to libtermcap with
references to libncurses.

To support binaries that have already been linked with the termcap
library, and for which you do not have the source, Debian provides a
package called termcap-compat.  This provides both libtermcap.so.2 and
/etc/termcap.  Install this package if the program fails to run with
the error message can't load library 'libtermcap.so.2', or complains
about a missing /etc/termcap file.


4.8.  Why can't I install AccelX?

AccelX uses the termcap library for installation. See about termcap
(4.7) above.

4.9.  Why do I get Can't find libX11.so.6 errors when I try to run foo?

This error message could mean that the program is in a.out format. In
this case you need to install the xcompat package.


4.10.  Can I install and compile a kernel without some Debian-specific
       tweaking?

Yes.  But you have to understand the Debian policy with respect to
headers.  The Debian C libraries are built with the most recent stable
releases of the gcc headers.  For example, the Debian-1.2 release used
version 5.4.13 of the headers.  This practice contrasts with the Linux
kernel source packages distributed at all Linux FTP archive sites,
which uses even more recent versions of the headers.  The kernel
headers distributed with the kernel source are located in
/usr/include/linux/include/.

If you need to compile a program with kernel headers that are newer
than those provided by libc5-dev, then you must add
-I/usr/src/linux/include/ to your command line when compiling. This
came up at one point, for example, with the packaging of the
automounter daemon (amd).  When new kernels changed some internals
dealing with NFS, amd needed to know about them.  This required the
inclusion of the latest kernel headers.



5.  Software available in the Debian system


5.1.  What types of applications and development software are available for
      Debian GNU/Linux?

Like most Linux distributions, Debian GNU/Linux provides:
o  the major GNU applications for software development, file manipulation,
   and text processing, including gcc, libc, g++, make, texinfo, gnuplot,
   the Bash shell and numerous upgraded Unix utilities,
o  Perl and its libraries,
o  TeX, LaTeX, and dvips,
o  the X Window System, which provides a networked graphical user
   interface for Linux, and numerous X applications,
o  a full suite of other networking applications, including WWW servers,
   browsers, and development tools.

Nearly 700 packages, ranging from news servers and readers to sound
support, FAX programs, database and spreadsheet programs, image
processing programs, communications, net, and mail utilities, Web
servers, and even ham-radio programs are included in the
distribution. Another 50 software suites are available as Debian
packages, but are not formally part of Debian due to license
restrictions.

5.2.  Who wrote all that software?

o  For each package the authors of this program are credited in thefile
   /usr/doc/PACKAGE/copyright, where PACKAGE is to be substituted with
   the package's name. (Packages conforming to an older Debian
   Packaging Standard have this in the file /usr/doc/copyright/PACKAGE
    instead.)

o  Maintainers who package this software for the Debian Linux system
   are listed in the Debian control file (6.4) that comes with each
   package.


5.3.  How can I get a current list of programs that have been packaged for
      the Debian project?

A complete list is available from any of the Debian mirrors.  The file
indices/Packages-Master-i386.gz provides a list, including short
descriptions, of all packages that are available for computers with
80386 (or more advanced) chips. The file
indices/Packages-Master-m68k.gz provides a similar list of packages
that are available for computers with Motorola 68k0x0 CPUs.

The WWW interface to the Debian packages conveniently summarizes the
packages in each of about twenty sections of the Debian archive, as
well as the 10 most recently uploaded packages.


5.4.  What is missing from Debian GNU/Linux?

A list of packages which are most urgently needed for Debian is
maintained by Sven Rudolph.  For more details, see the section on
contributing to the Debian project (14.1).


5.5.  Where is 'which'?

This is a historical question, no longer relevant, but is included
with this FAQ because it may still hold the record as the single most
frequently asked question on the Debian mailing lists.

The functionality of the Berkeley utility which is provided in the
Bash shell by the built-in command type.  To learn the path name for
an executable file foo, use the command type foo.  To learn all the
paths where foo can be found, use type -a foo.

To accommodate users' lack of familiarity with this (in this writer's
opinion, obscure) feature of Bash, the Debian maintainers have built a
package called debianutils, which includes a Bash script called which.
This script includes only these lines:


   #!/bin/bash
   for i in $*; do
     type -all -path $i | head -1
   done

The debianutils package is normally stored in the base section of the
FTP archive, and is therefore part of the initial installation of
every Debian system.


5.6.  (How) Does Debian support Java?

The Java Development Kit from Sun is currently available as a Debian
package (jdk_VVV-RRR.deb).  The JDK will allow you to run Java
programs and applets, and write your own.  If your kernel is properly
configured (see below), the JDK will allow you to run Java programs
just like other executables.  The JDK package also includes a number
of demo programs.

Debian's kernel is configured with Java support built in as a module
(i.e., CONFIG_BINFMT_JAVA=m).  Users who wish to build their own
custom kernel (10.1) can of course omit this if they choose.  Once
module support is available in the kernel, you need to make sure the
module is loaded.  You can do it at boot time by inserting the line
binfmt_java in the file /etc/modules. Alternatively, you can install
the module from the command line by executing the command insmod
DIRNAME/binfmt_java.o where DIRNAME is the name of the directory where
the modules that have been built for the version of the kernel now
running are stored. On a system with the 2.0.0 version of the kernel,
DIRNAME is likely to be /lib/modules/2.0.0/fs/. You can check that a
module is loaded using the command lsmod.

Running a Java applet requires a browser with the capability to
recognize and execute them.  The Netscape browser that can be
installed as a Debian package will run Java applets.  (The Netscape
source code is not publicly available.  The Debian netscape package
provides a wrapper which aids the installation and management of
Netscape on a Debian system.  This is actually a good example of the
integration of commercial packages with the Debian system.)

A final note of mixed blessings: Sun's licensing policies on the JDK
are becoming more restricted with time, so this package may not be
available as part of Debian soon.  It is possible that it may be
available in the same way that Netscape is available for Debian Linux.
Better news is that a number of programs are currently being developed
with may provide attractive publicly-available alternatives.


5.7.  What are all those directories
      (stable/development/non-free/contrib/project) at the Debian FTP
      archives?

The software that has been packaged for Debian GNU/Linux is available
in one of several directory trees on each Debian mirror site.


5.7.1 Top-level Directories

The Major Package Trees:

   o   Debian-1.2: This directory contains the packages which formally
       constitute the most recent release of the Debian Linux
       system. The contents of this directory do not change.
   o   Debian-1.2-updates: Updates to the current release are in this
       directory.

   o   Debian-1.2.x, a.k.a. stable: A copy of the current release
       with the updates applied.  The minor number is changed whenever new
       updates are added.
   o   non-free:  This directory contains packages whose distribution is
       restricted in a way which requires that distributors take careful
       account of the specified copyright requirements. For example, some
       packages have licenses which prohibit commercial distribution.
       Others can be redistributed but are in fact shareware and not
       freeware.  The licenses of each of these packages must be
       studied, and possibly negotiated, before the packages are
       included in any redistribution (e.g., in a CD-ROM).
   o   contrib: This directory contains packages which are freely
       distributable, but do not meet the policy requirements for
       distribution by the Debian project for some reason, e.g., the
       packages have some unusual restriction on modification by other
       users, or are only available in binary form.  For such
       packages, the project cannot given the user any means to assure
       that they are free of Trojan horses, and cannot port them to
       other architectures.
       Binary-only packages which are not freely redistributable are
       placed in the non-free directory.

Supplementary directories:

   o   tools: DOS utilities for creating boot disks, partitioning your
       disk drive, compressing/decompressing files, and booting Linux.
   o   upgrades: Files needed for upgrading a debian-0.93 system (based
       on a.out binary format files) to Debian-1.1 (or later, based on
       ELF binary files).  Included are instructions for upgrading
       (either manually using dpkg, or more automatically, using
       dselect), along with a copy of the particular version of the
       package management tool, dpkg that must be used in a.out
       systems to start the upgrade, and a list of files that will be
       needed in order to do the upgrade.
   o   doc: Documentation, instructions on how to submit bug reports.
   o   debian-lists: Archives of the Debian mailing lists.

Of particular interest to developers:

   o   development: A snapshot of the current development system.  Users
       are welcome to use and test these packages, but are warned
       about their state of readiness.
   o   project/experimental/: This directory contains packages and tools
       which are being developed specifically for the Debian project,
       and are still in the testing stage.  Users are welcome to use
       and test these packages, but warned about their state of
       readiness.
   o   private/project/Incoming/: Packages that have been uploaded by
       developers, and which are awaiting placement in the directory
       hierarchy by the distribution maintainer.
   o   indices/:  Various lists, including the Packages-Master file.


5.7.2 Sub-directories

Within each of the major directory trees (stable, non-free, contrib,
and development, but not project/experimental), which is too small to
subdivide), the binary packages reside in sub-directories whose names
indicate the chip architecture for which they were compiled:

o  binary, which is normally a link to binary-i386.
o  binary-all, for packages which are architecture-independent.  These
   include, for example, Perl scripts.
o  binary-i386, for packages which execute on 80x86 machines.
o  binary-m68k, for packages which execute on machines based on one of
   the Motorola 680x0 processors.  Currently this is done mainly for
   Atari and Amiga computers, and also for some VME based industry
   standard boards.
   There is no port of Linux to the old m68k based Macintoshes,
   because Apple did not supply the needed hardware information.
o  binary-sparc, for packages which execute on Sun Sparcstations.
o  binary-alpha, for packages which execute on DEC Alpha machines.


5.8.  Is source code included with the system?

Source code is included for everything in the Debian system. Most of
the license terms of programs in the system require that source code
be distributed along with the programs, or that an offer to provide
the source code accompany the programs.

Source code may or may not be available for packages in the contrib
and non-free directories, which are not formally part of the Debian
system.


5.9.  How can I check that I am using a Debian system?

The existence of the program dpkg shows that you should be able to
install Debian packages on your system.

In order to make sure that your system has been installed from the
real Debian base disks check for the existence of /etc/debian_version.


5.10.  How can I tell what version of the Debian system I am using?

There is a file, /etc/debian_version, which contains a single one-line
entry giving the version number of the release, as defined by the
package base.

Users should be aware, however, that the Debian system consists of
many parts, each of which can be updated (almost) independently.  Each
Debian release contains well defined and unchanging contents.  Updates
are separately available.  For a one-line description of the
installation status of package foo, use the command dpkg --list foo.
(With no arguments, this command prints out versions of all installed
packages.)

For a more verbose description, use dpkg --status foo.


5.11.  How does Debian support non-English languages?

o  Debian GNU/Linux is distributed with keymaps for nearly two dozen
   keyboards, and with utilities (in the kbd package) to install,
   view, and modify the tables. The installation prompts the user to
   specify the keyboard he will use.

o  Support for French-, German-, Italian- and Spanish-language manual
   pages is provided through the manpages-fr, manpages-de, manpages-it
   and manpages-es packages.  To access an NLS manual page, the user
   must set LC_MESSAGES to the appropriate string.  In the case of the
   German-language manual pages, LC_MESSAGES must be set to 'de_DE'.
   The man program will then search for German manual pages under
   /usr/man/de_DE/.

5.12.  What about the US export regulation limitations?

US laws place restrictions on the export of defense articles, which
includes some types of cryptographic software. PGP and ssh fall into
this category.

To prevent anyone from taking unnecessary legal risks, certain Debian
GNU/Linux packages are only available from a non-US site
( ftp://os.inf.tu-dresden.de:/pub/debian-non-US/ ) , there is a list of
mirror sites
( ftp://os.inf.tu-dresden.de/pub/debian-non-US/README.mirrors )



6.  Basics of the Debian Package Management System


6.1.  What is a Debian package?

Packages generally contain all of the files necessary to implement a
set of related commands or features.  There are two types of Debian
packages:

o  Binary packages, which contain executables, configuration files,
   man/info pages, copyright information, and other documentation.
   These packages are distributed in a Debian-specific archive format
   (6.2); they are usually distinguished by having a '.deb' file
   extension.  Binary packages can be unpacked using the Debian
   utility dpkg; details are given in its manual page.

o  Source packages, which consist of a .dsc file describing the
   source package (including the names of the following files), a
   .orig.tar.gz file that contains the original unmodified source in
   gzip-compressed tar format and usually a .diff.gz file that
   contains the Debian-specific changes to the original source.  The
   utility dpkg-source packs and unpacks Debian source archives;
   details are   provided in its manual page.

Installation of software by the package system uses dependencies which
are carefully designed by the package maintainers.  These dependencies
are documented in the control file associated with each package.  For
example, the package containing the GNU C compiler (gcc) depends on
the package binutils which includes the linker and assembler.  If a
user attempts to install gcc without having first installed binutils,
Debian's package system will send an error message that it also needs
binutils, and will install gcc only if the user agrees to install
binutils first.  (However, this facility can be overridden by the
insistent user.)  See more details on package dependencies (6.9)
below.

Debian's packaging tools can be used to:
o  manipulate and manage packages or parts of packages,
o  aid the user in the break-up of packages that must be transmitted
   through a limited-size medium such as floppy disks,
o  aid developers in the construction of package archives, and
o  aid users in the installation of packages which reside on a remote FTP
   site.


6.2.  What is the format of a Debian binary package?

A Debian package, or a Debian archive file, contains the executable
files, libraries, and documentation associated with a particular suite
of program or set of related programs.  Normally, a Debian archive
file has a filename that ends in .deb.

The internals of this Debian binary packages format are described in
the deb(5) manual page. This internal format is subject to change,
therefore always use dpkg-deb(8) for manipulating .deb files.

6.3.  Why are Debian package file names so long?

The Debian binary package file names conform to the following
convention: foo_VersionNumber-DebianRevisionNumber.deb

Note that foo is supposed to be the package name. As a check, one can
learn the package name associated with a particular Debian archive
file (.deb file) in one of these ways:

o  inspect the Packages file in the directory where it was stored in a
   Debian FTP archive site.  This file contains a stanza describing
   each package; the first field in each stanza is the formal Package Name.
o  use the command dpkg --info foo_VVV-RRR.deb.  This sends a message to
   STDOUT which gives, among other things, the Package Name
   corresponding to the archive file being unpacked.

The VVV component is the version number specified by the upstream
developer.  There are no standards in place here, so the version
number may have formats as different as 960428 and 2.7.2.l.3.

The RRR component is the Debian revision number, and is specified by
the Debian developer (or an individual user if he chooses to build the
package himself).  This number corresponds to the revision level of
the Debian package (which includes the Debian-specific Makefile,
called debian/rules, as well as the Debian control file, usually
called debian/control).  Thus, a new revision level usually signifies
changes in the Debian Makefile, the Debian control file, the
installation or removal scripts, or in the configuration files used
with the package.


6.4.  What is a Debian control file?

Specifics regarding the contents of a Debian control file are provided
in the dpkg programmer's manual (
ftp://ftp.debian.org/debian/doc/package-developer/programmer.ps.gz ) .
Briefly, a sample control file is shown below for the Debian package
hello:


   Package: hello
   Version: 1.3-13
   Architecture: i386
   Depends: libc5 (>= 5.2.18)
   Installed-Size: 31
   Maintainer: Ian Jackson <[e-mail]>
   Description: The classic greeting, and a good example
    The GNU hello program produces a familiar, friendly greeting.  It
    allows nonprogrammers to use a classic computer science tool which
    would otherwise be unavailable to them.
    .
    Seriously, though: this is an example of how to do a Debian
   package.
    It is the Debian version of the GNU Project's `hello world' program
    (which is itself an example for the GNU Project).


The Package field gives the package name.  This is the name by which
the package can be manipulated by the package tools, and usually
similar to but not necessarily the same as the first component string
in the Debian archive file name.

The version field gives both the upstream developer's version number
and (in the last component) the revision level of the Debian package
of this program as explained in (6.3).

The Architecture field specifies the chip for which this particular
binary was compiled.

The Depends field gives a list of packages that have to be installed
in order to install this package successfully.

The Installed-Size indicates how much disk space the installed package
will consume. This is intended to be used by installation front-ends
in order to show whether there is enough disk space available to
install the program .

The Maintainer field gives the e-mail address of the person who is
currently responsible for maintaining this package.

The Description field gives a brief summary of the package's features.


6.5.  What is a Debian conffile?

Conffiles are listings of configuration files, usually placed in /etc,
that the package management system will not overwrite when a package
is upgraded. This ensures that local values for the contents of these
files will be preserved, and is a critical feature enabling the
in-place upgrade of packages on a running system.

To determine exactly which files are preserved during an upgrade,
run dpkg --status package.


6.6.  What is a Debian preinst, postinst, prerm, and postrm script?

These files are executable scripts which are automatically run before
or after a package is installed. Along with a file named control, all
of these files are part of the control section of a Debian archive
file. The individual files are:

preinst    This script executes before that package will be unpacked from
   its Debian archive (.deb) file. Many 'preinst' scripts stop
   services for packages which are being upgraded until their
   installation or upgrade is completed (following the successful
   execution of the 'postinst' script).

postinst    This script typically completes any required configuration
   of the package foo once foo has been unpacked from its Debian
   archive (.deb) file. Often, 'postinst' scripts ask the user for
   input, and/or warn the user that if he accepts default values, he
   should remember to go back and re-configure that package as the
   situation warrants.  Many 'postinst' scripts then execute any
   commands necessary to start or restart a service once a new package
   has been installed or upgraded.  It is a good idea to check the
   contents of the 'postinst' script for any configuration advice,
   when trying out a package for the first time.

prerm    This script typically stops any daemons which are associated with
   a package.  It is executed before the removal of files associated
   with the package.

postrm    This script typically modifies links or other files associated
   with foo. (See notes on Virtual packages (6.8).)

Currently all of the control files can be found in /var/lib/dpkg/info.
The files relevant to package foo begin with the name foo and have
file extensions of preinst, postinst, etc., as appropriate.  The file
foo.list in that directory lists all of the files that were installed
with the package foo. (Note that the location of these files is a dpkg
internal; you should not rely on it.)


6.7.  What is a Required/Important/Standard/Optional/Extra package?

Each Debian package is assigned a priority by the distribution maintainers,
as an aid to the package management system.  The priorities are:

o  Required packages are necessary for the proper functioning of
   the system.  This inludes all tools that are necessary to repair
   system defects.  You must not remove these packages or your system
   may become totally broken and you may probably not even be able to
   use dpkg to put things back.  Systems with only the Required
   packages are probably unusable, but they do have enough
   functionality to allow the sysadmin to boot and install more
   software.

o  Important packages should be found on any Unix-like system.  Other
   packages which the system will not run well or be usable without
   will be here. This does NOT include Emacs or X11 or TeX or any
   other large applications.  These packages only constitute the bare
   infrastructure.

o  Standard packages are standard on any Linux system, including a
   reasonably small but not too limited character-mode system. This is
   what will install by default if users do not select anything
   else. It does not include many large applications, but it does
   include Emacs (this is more of a piece of infrastructure than an
   application) and a reasonable subset of TeX and LaTeX (if this
   turns out to be possible without X).

o  Optional packages include all those that you might reasonably want
   to install if you did not know what it was or do not have
   specialized requirements.  This includes X11, a full TeX
   distribution, and lots of applications.
o  Extra packages conflict with others with higher priorities, or are
   only likely to be useful if you already know what they are or have
   specialized requirements.


6.8.  What is a Virtual Package?

A virtual package is a generic name that applies to any one of a group
of packages, all of which provide similar basic functionality.  For
example, both the tin and trn programs are both news readers, and
should therefore satisfy any dependency of a program that required a
news reader on a system in order to work or to be useful. They are
therefore both said to provide the virtual package called news-reader.

Similarly, smail and sendmail both provide the functionality of a mail
transport agent.  They are therefore said to provide the virtual
package, mail transport agent.  If either one is installed, then any
program depending on the installation of a mail-transport-agent will
be satisfied by the existence of this virtual package.

Debian provides a mechanism so that, if more than one package which
provide the same virtual package is installed on a system, then system
administrators can set one as the preferred package.  The relevant
command is update-alternatives, and is described further in the
section on diversions (11.8).


6.9.  What is meant by saying that a file
      Depends/Recommends/Suggests/Conflicts/Replaces/Provides another
      package ?

The Debian package system has a range of package dependencies which
are designed to indicate (in a single flag) the level at which Program
A can operate independently of the existence of Program B on a given
system:

o  Package A depends on Package B if B absolutely must be installed in
   order to run A.  In some cases, A depends not only on B, but on a
   version of B.  In this case, the version dependency is usually a
   lower limit, in the sense that A depends on any version of B more
   recent than some specified version.

o  Package A recommends Package B, if the package maintainer judges
   that most users would not want A without also having the
   functionality provided by B.

o  Package A suggests Package B if B contains files that are related to
   (and usually enhance) the functionality of A.

o  Package A conflicts with Package B when A will not operate if B is
   installed on the system.  Most often, conflicts are cases where A
   contains files which are an improvement over those in B. Conflicts
   are often combined with replaces.

o  Package A replaces Package B when files installed by B are removed
   and (in some cases) over-written by files in A.

o  Package A provides Package B when all of the files and functionality
   of B are incorporated into A.  This mechanism provides a way for
   users with constrained disk space to get only that part of package
   A which   they really need.

More detailed information on the use of these terms can be found in
the Debian programmer's manual.


6.10.  What is meant by Pre-Depends?

Pre-Depends is a special dependency.

In the case of most packages, dpkg will unpack its archive file (i.e.,
its .deb file) independently of whether or not the files on which it
depends exist on the system.  Simplistically, unpacking means that
dpkg will extract the files from the archive file that were meant to
be installed on your filesystem, and put them in place.  If those
packages depend on the existence of some other packages on your
system, dpkg will refuse to complete the installation by executing its
configure action until the other packages are installed.

However, for some packages, dpkg will refuse even to unpack them until
certain dependencies are resolved.  Such packages are said to
Pre-depend on the presence of some other packages. The Debian project
provided this mechanism to support the safe upgrading of systems from
a.out format to ELF format, where the order in which packages were
unpacked was critical.

More detailed information on the use of these terms can be found in
the Debian programmer's manual.

6.11.  What is meant by unknown/install/remove/purge/hold in the package
       status?

These want flags tell what the user wanted to do with a package (as
indicated either by the user's actions in the Select section of
dselect, or by the user's direct invocations of dpkg).  Their meanings
are:

o  unknown  - the user has not said whether he wants the package
o  install  - the user wants the package installed or upgraded
o  remove   - the user wants the package removed, but does not want to
   remove any existing configuration files.
o  purge    - the user wants the package to be removed completely,
   including configuration files.
o  hold     - the user wants this package not to be processed, i.e., he
   wants to keep the current version with the current status whatever
   that is.

6.12.  Where will I get detailed info on creating Debian packages?

See the dpkg programmer's manual and the Debian policy manual (12.1)



7.  The Debian Package Management Tools


7.1.  What program(s) does Debian provide for managing its packages?


7.1.1 dselect

This program is a menu-driven interface to the Debian package
management system.  It is particularly useful for first-time
installations and large-scale upgrades.  dselect can

o  guide the user as he/she chooses among packages to install or
   remove, ensuring that no packages are installed that conflict with
   one another, and that all packages required to make each package
   work properly are installed;
o  warn the user about inconsistencies or incompatibilities in their
   selections;
o  determine the order in which the packages must be installed;
o  automatically perform the installation or removal; and
o  guide the user through whatever configuration process are required for
   each package.

dselect begins by presenting the user with a menu of 7 items, each of
which is a specific action.  The user can select one of the actions by
using the arrow keys to move the highlighter bar, then pressing the
ENTER key to select the highlighted action.

What the user sees next depends on the action he selected.  If he
selects any option but Access or Select, then dselect will simply
proceed to execute the specified action: e.g., if the user selected
the action Remove, then dselect would proceed to remove all of the
files selected for removal when the user last chose the Select action.

Both the Access menu item and the Select menu item lead to additional
menus.  In both cases, the menus are presented as split screens; the
top screen gives a scrollable list of choices, while the bottom screen
gives a brief explanation (info) for each choice.

Extensive on-line help is available: Use the '?' key to get to a help
screen, then use the '.' key to see each of the several pages of help
one screen at a time.

Some users find it easier to navigate dselect when it is colorized.
To see color screens in dselect, be sure that you have executed:
export TERM=linux before invoking dselect.

The order in which the actions are presented in the first dselect menu
represents the order in which a user would normally choose dselect to
install packages.  However, a user can pick any of the main menu
choices as often as needed (including not at all, depending on what
one wants to do).

o  Begin by choosing an Access Method.  This is the method by which the
   user plans on accessing Debian packages; e.g., some users have
   Debian packages available on CD-ROM, while others plan to fetch
   them using anonymous ftp.  The selected Access Method is stored
   after dselect exits, so if it does not change, then this option
   need not be invoked again.

o  Then Update the list of available packages.  To do this, dselect
   reads the file Packages.gz which should be included in the top
   level of the directory where the Debian packages to be installed
   are stored.  (But if it is not there, dselect will offer to make it
   for you.)

o  Select specific packages for installation on his system.
   After choosing this menu item, the user is first presented with a
   full screen of help; he can exit it (and any help screen) by
   pressing the SPACEBAR.  Better (for first time users) is to read
   all of the help screen, but repeatedly pressing the '.' key to
   fetch one page of help after another.  Once the user exits the Help
   screen, he sees the split-screen menu for choosing packages to
   install (or remove). The top screen is a relatively narrow window
   into the list of Debian's nearly 700 packages; the bottom screen is
   a window into info about the package or group of packages which are
   highlighted in the top.

   First-time users are often confused by these aspects of the Select
   screen:

   -  Deselecting a  packages: One can specify which packages should be
      removed (previously called deselecting an item) by highlighting
      a package name or the label for a group of packages (e.g., All) and
      then pressing either:
      *  the '-' key.  This removes most of the files associated with the
         package, but preserves the files listed as configuration files
         (6.5) and other configuration information.
      *  the '_' key.  This removes every file that is part of the
         package.

      Note that if you deselect All Packages your system will be reduced
      to the initial installed base packages.  This is probably what
      you wanted.

   -  Putting a package on hold (by pressing '='): This effectively
      tells dselect not to upgrade a package even if the version
      currently installed on your system is not as recent as the
      version that is available in the Debian repository you are using
      (this was specified when you set the Access Method).  (The
      version that is available in the repository is given in the file
      Packages.gz that is read when the Update menu choice is
      activated.)
      Putting a package on unhold (by pressing ':'): This is the
      default, and means that the packages will be upgraded if a newer
      version is available.

   -  The order in which the packages are presented: The default order
      is to present packages by Priority; within each priority,
      packages are presented in order of the directory (a.k.a.
      section) of the archive in which they are stored.  Given this
      sort order, some packages in section A (say) may be presented
      first, followed by some packages in section B, followed by more
      packages (of lower priority) in section A. Users can select a
      different presentation order by using the 'o' key to cycle
      between various options for sorting the packages.
   -  Meanings of the labels at the top of the screen: The labels at
      the top can be expanded by using the 'v' (verbose) key.  This
      action pushes much of the text that formerly fit onto the
      display off to the right.  To see it, press the right arrow; to
      scroll back to the left, press the left arrow.
   -  What to do with a package conflict/dependency screen: If a user
      selects (for installation or removal) a package, e.g., foo.deb
      that depends on or recommends another package, e.g., blurf.deb,
      then dselect will place the user in a sub-screen of the main
      selection screen. This process begins by presenting the user
      with a full-screen Help file, which can be escaped by pressing
      SPACEBAR.

      Thereafter, the user can choose among the related packages,
      accepting the suggested actions (to install or not), or
      rejecting them.  To do the latter, press SHIFT-D; to return to
      the former, press SHIFT-U.  In any case, the user can save his
      selections and return to the main selection screen by pressing
      SHIFT-Q.

o  Users returning to the main menu can then select the Install menu
   item to unpack and configure the selected packages.  Alternatively,
   users wishing to remove files can choose the Remove menu item.  At
   any point, users can choose Quit to exit dselect; users' selections
   are preserved by dselect.


7.1.2 dpkg

This is the main package management program. dpkg can be invoked with
many options.  Some common uses are:

o  Find out all the options:  dpkg --help.

o  Print out the control file (and other information) for a specified
   package: dpkg --info foo_VVV-RRR.deb

o  Install a package (including unpacking and configuring) onto the
   file system of the hard disk: dpkg --install foo_VVV-RRR.deb.

o  Unpack (but do not configure) a Debian archive into the file system
   of the hard disk: dpkg --unpack foo_VVV-RRR.deb.  Note that this
   operation does not necessarily leave the package in a usable state;
   some files may need further customization to run properly. This
   command removes any already-installed version of the program and
   runs the preinst (6.6) script associated with the package.

o  Configure a package that already has been unpacked: dpkg --configure
   foo.  Among other things, this action runs the postinst (6.6)
   script associated with the package.  It also updates the files
   listed in the conffiles for this package. Notice that the
   'configure' operation takes as its argument a package name (e.g.,
   foo), not the name of a Debian archive file (e.g.,
   foo_VVV-RRR.deb).

o  Extract a single file named blurf (or a group of files named blurf*
   from a Debian archive: dpkg --fsys-tarfile foo_VVV-RRR.deb | tar
   -xf - blurf*

o  Remove a package (but not its configuration files): dpkg --remove
   foo.

o  Remove a package (including its configuration files): dpkg --purge
   foo.

o  List the installation status of packages containing the string foo*:
   dpkg --list 'foo*'.


7.1.3 dpkg-deb

This program manipulates Debian archive(.deb) files. Some common uses
are:

o  Find out all the options:  dpkg-deb --help.

o  Determine what files are contained in a Debian archive file:
   dpkg-deb --contents foo_VVV-RRR.deb)

o  Extract the files contained in a named Debian archive into a user
   specified directory: dpkg-deb --extract foo_VVV-RRR.deb tmp
   extracts each of the files in foo_VVV-RRR.deb into the directory
   tmp/.  This is convenient for examining the contents of a package
   in a localized directory, without installing the package into the
   root file system.

More information is given in the manual page dpkg-deb(1).


7.1.4 dpkg-split

This program splits large package into smaller files (e.g., for
writing onto a set of floppy disks), and can also be used to merge a
set of split files back into a single file. It can only be used on a
Debian system, since it calls the program dpkg-deb to parse the debian
package file into its component records. For example, to split a big
.deb file into N parts,

o  Execute the command dpkg-split --split foo.deb. This will produce N
   files each of approximately 460 KBytes long in the current
   directory.

o  Copy those N files to floppy disks.

o  Copy the contents of the floppy disks onto the hard disk of your
   choice on the other machine.

o  Join those part-files together using dpkg-split --join "foo*".


7.2.  Debian claims to be able to update a running program; how is this
      accomplished?

Debian GNU/Linux provides a program called the start-stop-daemon which
is used by installation scripts to start daemons at boot time or to
stop daemons when the kernel runlevel is changed (e.g., from
multi-user to single-user or to halt). The start-stop-daemon command
is also used when a new package containing a daemon is installed, to
stop running daemons, and restart them as necessary, e.g., when a
package is being installed with an updated configuration script.

7.3.  How can I tell what packages are already installed on a Debian
      system?

To learn the status of all the packages installed on a Debian system,
execute the command dpkg --list.  This prints out a one-line summary
for each package, giving a 2-letter status symbol, the package name,
the version which is installed, and a very brief description.

To learn the status of packages whose names match the string any
pattern beginning with foo by executing the command dpkg --list 'foo*'
To get a more verbose report for a particular package, execute the
command: dpkg --status foo.


7.4.  How can I find out what package produced a particular file?

To identify the package that produced the file named foo execute either:

o  dpkg --search filename.

   This searches for filename in installed packages.  (This is
   (currently) equivalent to searching all of the files having the
   file extension of .list in the directory /var/lib/dpkg/info/.)

o  grep foo Contents, or zgrep foo Contents.gz.

   This searches for files which contain the substring foo in their
   full path names.  The files Contents and Contents.gz reside in the
   major package directories (stable, non-free, contrib, development)
   at a Debian FTP site.  A Contents file refers only to the packages
   in the subdirectory tree where it resides.  Therefore, a user might
   have to search more than one Contents files to find the package
   containing the file foo.

   This method has the advantage over dpkg --search in that it will
   find files in packages that are not currently installed on your
   system.


8.  Getting and Installing Debian GNU/Linux


8.1.  Where/how can I get the Debian installation disks?

You can get the installation disks by downloading the appropriate
files from the Debian FTP site: ( ftp://ftp.debian.org/debian/ ) and
its mirrors ( http://www.debian.org/ftplist.html ) .  From the
directory stable/disks-i386/current/, you will need:

The Installation Guide.     This document gives detailed installation
   instructions.  It is available in the files install.txt (ASCII) and
   install.html (HTML).

The Rescue Disk.    This disk is the boot disk and contains a minimal
   file system and the installation program.

   If your system can boot from a 1.44 MByte floppy disk drive,
   download the file called resq1440.bin.  On the other hand, if your
   system can boot only from a 1.2 MByte floppy disk drive, download
   the file called resq1200.bin.  (There seems to be no resq1200.bin
   file available right now.)

The Device Driver Disk.    This disk contains many device drivers that can
   be loaded into the Linux kernel.

   If your system has a 1.44 MByte floppy disk drive, you can use the
   file called drv1440.bin.  On the other hand, if your system only
   has a 1.2 MByte floppy disk drive, you have to download the file
   called drv1200.bin.

The Base  Disks.   These disks contain the software that is necessary to
   have a bare-bones system.

   If your system has a 1.44 MByte floppy disk drive, you can use
   the files called base14-1.bin, base14-2.bin, base14-3.bin and
   base14-4.bin.  On the other hand, if your system only has a 1.2
   MByte floppy disk drive, you have to download the files called
   base12-1.bin, base12-2.bin, base12-3.bin and base12-4.bin.

Once you have downloaded these files, transfer them to a disk as
described in the Installation Guide.

You may, of course, get these disks from a friend. You can make as
many copies as you want.  Debian is freely redistributable, provided
you follow a few simple rules.  For more information, see The GNU
General Public License (
http://www.gnu.ai.mit.edu/copyleft/copyleft.html ) .

If you cannot get copies of the installation disks from one of the
Debian FTP sites or from a friend, then make a request to one of the
Debian mailing lists.  See the debian-user mailing list (12.2). The
likelihood is very high that someone will be willing to help.


8.2.  OK, I have got the disks; how do I install the system?

Complete, detailed instructions are given in the Installation Guide
that you downloaded above. Follow these instructions!


8.3.  How (and on what media) can I get the Debian packages?

Once the base system has been installed, you can complete the
installation of your Debian GNU/Linux system by accessing packages on
any (or several) of these media:

o  a CD-ROM (8.4) containing Debian.
o  a remote NFS (8.5) server.
o  a partition of your hard disk (8.7).
o  a collection of floppy disks (8.6).
o  a remote system accessible by anonymous ftp (8.8).

In each case, you can use either

o  dselect (7.1.1), Debian's user-interface program to its package
   system.  (This will help you mount the device containing the Debian
   package files (if necessary), and then guide you through the
   selection of packages and their installation on your system.)  Or,

o  use dpkg (7.1.2) directly to control the installation of individual
   packages.  Debian gurus quizzically refer to this approach as
   installing packages by hand.

8.4.  How do I get and install the Debian from CD-ROM?

Linux supports the ISO 9660 (CD-ROM) file system with Rock Ridge
extensions (formerly known as High Sierra).  Several vendors provide
Debian in this format; these vendors have directly supported the
Debian project:

o  iConnect Corp.: i-Connect.Net provides the master FTP system
   used by Debian developers, and its network connection and system
   administration.  They provide our 168 developers with free accounts
   on a system that is exclusively for our use, and they run our DNS
   domain.  They also maintain several Debian packages.  Use the
   following contact info to order their CD-ROM:
   -  WWW:  ( http://www.i-connect.net/i-connect/services/cdrom.html )
   -  E-Mail (sales): [e-mail]
   -  E-Mail (help): [e-mail]
   -  Phone from inside the US: 1-503-641-8774
   -  Phone from outside the US: [phone]
   -  Postal address:


                 iConnect Corp.
                 14355 SW Allen Blvd., Suite 140
                 Beaverton, OR 97005

o  Flexible Software: This company maintains 8 Debian packages, and
   puts a lot of manpower into supporting users on the debian-user
   mailing list and refining the system design with our
   developers. They have carefully documented the development of one
   of the two methods used to upgrade from Debian 0.93 to Debian 1.1.

   -  E-Mail (sales): [e-mail]
   -  Postal address:


                 Flexible Software
                 1000 McCrackin Road
                 Tallahassee, FL 32308



To install packages provided on a CD-ROM, you must have CD-ROM support
built into the kernel you use.  This may require a a custom
modification of the file /etc/conf.modules, or (unlikely nowadays) a
special argument on the boot command line.

To mount a CD-ROM under the mount point /cdrom/ (a directory which
should have been created during installation), use these commands:

o  mount -t iso9660 /dev/hdd /cdrom/ if the CD-ROM is an IDE drive on the
   secondary IDE controller, or
o  mount -t iso9660 /dev/scd0 /cdrom/ if the CD-ROM is a SCSI drive, or
o  mount -t iso9660 /dev/xxxxx /cdrom/ where xxxxx refers to CD-ROMs which
   are sbpcd, cdu31a, or some other proprietary (non-IDE) drive.


8.5.  How do I get and install Debian from an NFS-mounted drive?

Debian packages on remote hosts can be installed via the Network File
System using a SLIP, PPP, PLIP or Ethernet connection. SLIP and PPP
require the netbase and netstd packages to be installed first.  These
packages are not part of the Debian base system, and must be obtained
by one of the other methods described in this section.

No special kernel configuration (other than the network drivers for
SLIP, PPP, PLIP, or one of the Ethernet cards) is necessary to access
a remote filesystem using NFS.  As with all network communication, the
appropriate ifconfig and route commands will have to be issued before
accessing a remote disk using NFS.

To mount a network-accessible file system using NFS (say,
/var/spool/debian/) under the local directory /usr/local/debian/,
issue the command

o  mount -t nfs host.fully-qualified.domain.name:/var/spool/debian/ -o
   ro,nosuid,soft /usr/local/debian/

To ensure that the filesystem is always accessible, the appropriate
string could be added to /etc/fstab:

o  rulway.leidenuniv.nl:/var/spool/ftp.pub.linux.debian/  /mnt/debian/  nfs
   ro,nosuid,soft

The preceding example shows the appropriate entry for the NFS site at
Leiden University, the Netherlands.  See README.mirror (
ftp://ftp.debian.org/debian/README.mirror ) for other sites providing
NFS access to their Debian mirror.


8.6.  How can I get/install the Debian from a set of floppy disks?

Copy the Debian packages onto formatted floppy disks.  Either a DOS,
the native Linux ext2, or the minix format will do; one just has to
use a mount command appropriate to the floppy being used.  Using
floppy disks has these complications:

o  Short MS-DOS filenames: If you are trying to place Debian package
   files onto MS-DOS formatted disks, you will find that their names
   are generally too long, and do not conform to the MS-DOS 8.3
   filename limitation.  To overcome this, Debian developers make all
   of their packages available by 8.3 filenames in separate msdos
   subdirectories ( stable/msdos-i386/, non-free/msdos-i386/,
   contrib/msdos-i386/, and development/msdos-i386/).  The files in
   these subdirectories are merely symbolic links to the Debian
   archive files; they only differ from the files in the binary-i386/,
   etc. directories by having shorter file names.

o  Large file sizes: Some packages are larger than 1.44 MBytes,
   and will not fit onto a single floppy disk.  To solve this
   problem, use the dpkg-split (7.1.4) tool, available in the tools
   directory at ( ftp://ftp.debian.org/debian/ ) and its mirrors (
   http://www.debian.org/ftplist.html ) .

You must have support in the kernel for floppy disks in order to read
and write to floppy disk; most kernels come with floppy drive support
included in them.

To mount a floppy disk under the mount point /floppy (a directory
which should have been created during installation), use:

o  mount -t msdos /dev/fd0 /floppy/ if the floppy disk is in drive A: and
   has an MS-DOS filesystem,
o  mount -t msdos /dev/fd1 /floppy/ if the floppy disk is in drive B: and
   has an MS-DOS filesystem,
o  mount -t ext2 /dev/fd0 /floppy/ if the floppy disk is in drive A: and
   has an ext2 (i.e., a normal Linux) filesystem.


8.7.  How can I get/install the Debian from my own hard disk?

The Debian packages can be installed from a hard disk on your system,
either IDE, EIDE, SCSI (including Jaz drives), or a drive connected
through a parallel port.

Kernel support must of course be available for the type of drive you
have.  The appropriate drivers are:

o  CONFIG_BLK_DEV_IDE for IDE or EIDE drives; most kernels include this
   driver.

o  CONFIG_SCSI for SCSI drives (including Jaz drives), along with one
   of the (many) drivers for your particular SCSI interface.

o  CONFIG_SCSI_PPA for the parallel port version of ZIP drives.

To start the installation invoke the program dselect, select the hard
disk access method and follow the instructions.

This will ask you for the device name where Debian resides. These
device names are constructed as follows:
(below X is to be substituted by the partition number (X =1,2,3, or 4))

o  /dev/hdaX if the disk is drive C: and has an MS-DOS filesystem,

o  /dev/sdaX if the disk is a SCSI drive and has the lowest SCSI ID of
   any SCSI device on your system,

o  /dev/sdbX if the disk is a SCSI drive and has the second lowest SCSI
   ID of any SCSI device on your system

o  /dev/ppa0 if the disk is a Zip drive.

Note that files on a disk partition having an MS-DOS filesystem must
conform to the DOS filename limitation of 8 characters plus a 3
character extension.  Files in the stable/msdos-i386/,
non-free/msdos-i386/, contrib/msdos-i386/, and development/msdos-i386/
directories conform to this limitation.


8.8.  How can I get and install Debian directly from a remote ftp site?

Install the Debian tool dpkg-ftp (9.2).  This package is currently
installed in the directory development/binary-all/net at
( ftp://ftp.debian.org/debian/ ) and its mirrors
( http://www.debian.org/ftplist.html ) . For details on installing a
package, see notes on dpkg (7.1.2).

Then invoke the program dselect, which will call dpkg-ftp for you,
guide you through the selection of packages, then install the
packages, without every downloading the packages themselves to your
machine.  This method is designed to save the user both disk space and
time. Note that no special kernel configuration is needed to access
and install Debian packages by this method.

To use this service of dselect, you will need to know:

o  the fully qualified domain name of the anonymous ftp site you plan
   to use.

o  the directory which contains the files you want to install, or the
   subdirectories which contain files you want to install.  This
   directory must contain a file called Packages (or its compressed
   equivalent, Packages.gz).


8.9.  How can I get and install Debian from a tape?

At present, installing packages directly from tape is not
supported. One can however, use tar, cpio, or afio to copy Debian
archive files onto a tape, then copy them onto your local disk for
installation.  In the same vein, floppy disks containing tar files
would have to be copied onto a local disk before they could be managed
with the Debian package tools.

8.10.  What is the latest version of Debian?

Currently there are three versions of Debian:

o  1.2: this is stable software, and will not change.
o  1.2.x, a.k.a. stable, a.k.a ; this  is  stable software, but it  may
   change when major fixes are incorporated.
o  the development version; this  is  the  version  currently  under
   development; it is updated continuously. You can retrieve packages
   from the development archive on any Debian FTP site and use them to
   upgrade your system at any time.

   It is planned that this will become a new Debian release about
   three months after the last release.


9.  Keeping Your Debian System Up To Date



9.1.  How can I upgrade my Debian 0.93 (or earlier) distribution, based on
      a.out format binaries, to 1.1 (or later), based on ELF binaries?

The directory upgrades/ contains files needed by users upgrading from
Debian 0.93R6 to Debian 1.1 (or later).  There are two ways to
upgrade:

o  the manual way, installing the packages by hand. Instructions are in
   upgrade_manual.doc.  You will also need the files UpGrade, base_list,
   and dpkg-*.deb.

o  using dselect to upgrade all the packages en masse. Instructions are in
   upgrade_dselect.doc.  You will also need dpkg-*.deb.

Note that the version of dpkg in this directory has the a.out binary
format.  The versions of dpkg in the development and stable trees have
the ELF format.


9.2.  How can I keep my Debian system current?

One could simply execute an anonymous ftp call to a Debian archive,
then peruse the directories until he finds the desired file, and then
fetch it, and finally install it using dpkg.  Note that dpkg will
install upgrade files in place, even on a running system. Sometimes, a
revised package will require the installation of a newly revised
version of another package, in which case the installation will fail
until/unless the other package is installed.

Many people find this approach much too time-consuming, since Debian
evolves so quickly---typically, a dozen or more new packages are
uploaded every week.  This number is larger just before a new major
release.  To deal with this avalanche, many people prefer to use an
automated programs.  Three different packages are available for this
purpose:

o  dpkg-ftp.  This is an access method for dselect. It can be invoked
   from within dselect, thereby allowing a user the ability to
   download files and install them directly in one step.  To do this,
   bring up the dselect program, choose option 0 (Choose the access
   method to use), highlight the option ftp then specify the remote
   hostname and directory. dpkg-ftp will then automatically download
   the files that are selected (either in this session of dselect or
   earlier ones).  Note that, unlike the mirror program, dpkg-ftp does
   not grab everything at a mirror site.  Rather, it downloads only
   those files which you have selected (when first starting up
   dpkg-ftp), and which need to be   updated.

   dpkg-ftp is available in the directory stable/binary-all/net/ on
   any Debian archive.

o  mirror.  This Perl script, and its (optional) manager program called
   mirror-master, can be used to fetch user-specified parts of a
   directory tree from a specified host via anonymous ftp. mirror is
   particularly useful for downloading large volumes of software.
   After the first time files have been downloaded from a site, a file
   called .mirrorinfo is stored on the local host.  Changes to the
   remote filesystem are tracked automatically by mirror, which
   compares this file to a similar file on the remote system and
   downloads only changed files.

   The mirror program is generally useful for updating local copies of
   remote directory trees.  The files fetched need not be Debian
   files.  (Since mirror is a Perl script, it can also run on non-Unix
   systems.)  Though the mirror program provides mechanisms for
   excluding files whose names match user-specified strings, this
   program is most useful when the objective is to download whole
   directory trees, rather than selected packages.

   The mirror program has been packaged for Debian, and is found in
   the directory stable/binary-all/net in the Debian FTP archive.

o  dftp.  This Perl script can be used to fetch user-specified Debian
   packages from a specified host.  It begins by downloading the
   Packages.gz files for the directories specified by the user (e.g.
   stable, contrib, non-free) and presents him with a list of
   packages.

   These are placed in various sections: new upgrades, downgrades, new
   packages, ignored upgrades, and ignored packages.  The user then
   selects the packages he wants and dftp downloads and installs them.
   This makes it very easy to have your Debian system 100% current all
   the time without downloading packages that you are not going to
   install.

   dftp can be used to call dselect (7.1.1), thereby providing an
   integrated way to fetch and update the Debian packages on one's
   system.  When the installation is finished, another dftp command
   can be used to remove the package archive (.deb) files.  Changes to
   the remote filesystem are tracked automatically by dftp, which
   compares the local Packages.gz file to the files on the remote
   system.  The dftp program is available as a script in the directory
   project/misc in the Debian FTP archive.


9.3.  Must I go into single user mode in order to upgrade a package?

No.  Packages can be upgraded in place, even in running
systems. Debian has a start-stop-daemon program that is invoked to
stop, then restart running process if necessary during a package
upgrade.


9.4.  Do I have to keep all those .deb archive files on my disk?

No.  If you have downloaded the files to your disk (which is not
absolutely necessary (see dpkg-ftp (9.2) or dftp (9.2))), then after
you have installed the packages, you can remove them from your system.


9.5.  How can I keep a log of the packages I added to the system?

dpkg keeps a record of the packages that have been unpacked,
configured, removed, and/or purged, but does not (currently) keep a
log of terminal activity that occured while a package was being so
manipulated. Some users overcome this simply by using tee:


   dpkg -iGOEB -R stable/binary non-free/binary contrib/binary | \
       tee -a /root/dpkg.log


The same command written using long options:

   dpkg --install --refuse-downgrade --selected-only \
     --skip-same-version --auto-deconfigure \
     --recursiv estable/binary non-free/binary contrib/binary | \
       tee -a /root/dpkg.log



10.  Debian and the kernel


10.1.  What tools does Debian provide to build custom kernels?

Users who wish to (or must) build a custom kernel are encouraged to
download the package kernel-package_VVV_all.deb (it is stored in
section misc at the Debian FTP archives).  This package contains the
script to build the kernel package, and provides the capability to
create a Debian kernel-image package just by running the command
make-kpkg kernel_image in the top-level kernel source directory. Help
is available by executing the command make-kpkg --help, and through
the manual page for make-kpkg(8).

Users must separately download the source code for the most recent
kernel (or the kernel of their choice) from their favorite Linux
archive site.  To build a custom kernel, users must have these
packages installed: gcc, libc5-dev, bin86, binutils, gawk, make, gzip,
and grep.

Executing the command dpkg --install kernel-package_VVV_all.deb sets
up the directory /usr/src/linux-VVV/, and sets up the link
/usr/src/linux to point to the directory /usr/src/linux-VVV/
containing the kernel sources.

Detailed instructions for using the package are given in the file
/usr/doc/kernel-package/README.  Briefly, one should:

o  Unpack the kernel sources, and cd to the newly created directory.

o  Modify the kernel configuration using one of these commands:
   --  make config  (for a tty one-line-at-a-time-interface).
   --  make menuconfig  (for an ncurses-based menu driven interface).
       Note that to use this option, the ncurses3.0-dev package must
       be installed.
   --  make xconfig  (for an X11 interface).  Using this option requires
       that relevant X packages be installed.

   Any of the above steps generates a new .config in the top-level kernel
   source directory.

o  Execute the command: make-kpkg -r Custom.N kernel_image, where
   N is a revision number assigned by the user.  The new
   Debian archive thus formed would have revision Custom.1, e.g.,
   kernel-image-2.0.27-Custom.1.deb for the Linux kernel 2.0.27.

o  Install the package created.

   --  Run dpkg --install /usr/src/kernel-image_VVV-Custom.N.deb to install
       the kernel itself.  The installation script will:
       *  run the boot loader, LILO (if it is installed),
       *  install the custom kernel in /boot/vmlinuz_VVV-Custom.N, and set
          up appropriate symbolic links to the most recent kernel version.

       *  prompt the user to make a boot floppy.  This boot floppy will
          contain the raw kernel only.  See additional notes for making a
          custom boot floppy (10.2).
   --  To employ a secondary boot loaders (e.g.,  loadlin), copy this image
       to other locations (e.g., an MS-DOS partition).

10.2.  How can I make a custom boot floppy?

This task is greatly aided by the Debian package
boot-floppies_VVV-RRR.deb, normally found in the binary/devel section
of the Debian FTP archive.  Shell scripts in this package produce boot
floppies in the SYSLINUX format.  These are MS-DOS formatted floppies
whose master boot records have been altered so that they boot Linux
directly (or whatever other operating system has been defined in the
syslinux.cfg file on the floppy). Other shell scripts in this package
produce emergency root disks and can even reproduce the base disks.

When the boot-floppies package is installed, it produces files which
reside in /usr/src/boot-floppies/, including the three scripts, called
bootdisk.sh, rootdisk.sh, and basedisk.sh.  Users of these scripts are
encouraged to read them and customize as appropriate.  In particular,
one should include the kernel of your choice when invoking the
bootdisk.sh script.  Be aware that this kernel cannot be used to load
the root disk into a RAMDISK unless it was compiled with
CONFIG_RAMDISK=y, and CONFIG_INITRD=y.

To write the kernel-image-2.0.27 package to the 1.44 MByte disk in
drive A: run this command:


   ./bootdisk.sh /usr/src/kernel-image-2.0.27_1.00.deb /dev/fd0 1440

Be sure to include the editor and whatever other tools you prefer when
building your custom root disk with ./rootdisk.sh.

Some people found that the boot and root disks make good emergency
floppies.


10.3.  What special provisions does Debian provide to deal with
       modules?

Debian's modconf package provides a shell script (/usr/sbin/modconf)
which can be used to customize the configuration of modules.  This
script presents a menu-based interface, prompting the user for
particulars on the loadable device drivers in his system.  The
responses are used to customize the file /etc/conf.modules (which
lists aliases, and other arguments that must be used in conjunction
with various modules), and /etc/modules (which lists the modules that
must be loaded at boot time).

Like the (new) Configure.help files that are now available to support
the construction of custom kernels, the modconf package comes with a
series of help files (in /usr/lib/modules_help/) which provide
detailed information on appropriate arguments for each of the modules.


10.4.  Can I safely de-install an old kernel, and if so how?

Yes.  The kernel-image-NNN.prerm script checks to see whether the
kernel you are currently running is the same as the kernel you are
trying to de-install.  Therefore you can remove unwanted kernel image
packages using this command:

dpkg --purge --force-remove-essential kernel-image-NNN



11.  Customizing your installation of Debian GNU/Linux


11.1.  How can I ensure that all programs use the same paper size?

The file /etc/papersize contains the name of the system-wide default
paper size (i.e.  letter or A4). It can be overwritten using the
PAPERSIZE environment variable. For details see the manual page
papersize(5).


11.2.  How can I configure an X11 program's application defaults ?

Debian's X11 installation expects you to leave the files in
/usr/X11R6/lib/X11/app-defaults/ unchanged. If you want to customise X
applications globally, put your customizations in
/etc/X11/Xresources. This file is marked as a configuration file, so
its contents will be preserved during upgrades.


11.3.  Every distribution seems to have a different boot-up method.  Tell
       me about Debian's.

Like all Unices, Debian boots up by executing the program init.  The
configuration file for init (which is /etc/inittab) specifies that the
first script to be executed should be /etc/init.d/boot.  This script
checks and mounts file systems, loads modules, starts the network
services (by calling the script /etc/init.d/network), sets the clock,
performs other initialization, and then runs all of the scripts
(except those with a '.' in the filename) in /etc/rc.boot/. The latter
script sets the default keyboard, recovers lost editor files, and
configures the serial ports.

After completing the boot process, init executes all start scripts in
a directory specified by the default runlevel (this runlevel is given
by the entry for id in /etc/inittab). Like most System V compatible
Unices, Linux has 7 runlevels:

0 (halt the system), 1 (single-user mode), 2 through 5 (various
multi-user modes), and 6 (reboot the system). Debian systems come with
id=2, which indicates that the default runlevel will be '2' when the
multi-user state is entered, and the scripts in /etc/rc2.d/ will be
run.

In fact, the scripts in any of the directories, /etc/rcN.d/ are just
symbolic links back to scripts in /etc/init.d/.  However, the names of
the files in each of the /etc/rcN.d/ directories are selected to
indicate the way the scripts in /etc/init.d/ will be run.
Specifically, before entering any runlevel, all the scripts beginning
with 'K' are run; these scripts kill services.  Then all the scripts
beginning with 'S' are run; these scripts start services.  The
two-digit number following the 'K' or 'S' indicates the order in which
the script is run.  Lower numbered scripts are executed first.

This approach works because the scripts in /etc/init.d/ all take an
argument which can be either 'start', 'stop', or 'reload', and will
then do the task indicated by the argument. For example, with the
argument 'reload' the command /etc/init.d/sendmail reload sends the
sendmail daemon a signal to reread its configuration file. These
scripts can be used even after a system has been booted to control
various processes.


11.4.  It looks as if Debian does not use rc.local to customize the boot
       process; what facilities are provided?

Suppose a system needs to execute script foo on start-up, or on entry
to a particular (System V) runlevel.  Then the system administrator
should:

o  Enter the script foo into the directory /etc/init.d/.
o  Run the Debian command update-rc.d with appropriate arguments,  to
   set up links between the (command-line-specified) directories rc?.d
   and /etc/init.d/foo.  Here, '?'  is a number from 0 through 6 and
   corresponds to each of the System V runlevels.
o  Reboot the system.

The command update-rc.d will set up links between files in the
directories rc?.d and the script in /etc/init.d/. Each link will begin
with a 'S' or a 'K', followed by a number, followed by the name of the
script.  Scripts beginning with 'S' in /etc/rcN.d/ are executed when
runlevel N is entered.  Scripts beginning with a 'K' are executed when
leaving runlevel N.

One might, for example, cause the script foo to execute at boot-up, by
putting it in /etc/init.d/ and installing the links with update-rc.d
foo defaults 19.  The argument 'defaults' refers to the default
runlevels, which are 2 through 5.  The argument '19' ensures that foo
is called before any scripts containing numbers 20 or larger.


11.5.  How does the package management system deal with packages that
       contain configuration files for other packages?

Some users wish to create, for example, a new server by installing a
group of Debian packages and a locally generated package consisting of
configuration files.  This is not generally a good idea, because dpkg
will not know about those configuration files if they are in a
different package, and may write conflicting configurations when one
of the initial group of packages is upgraded.

Instead, create a local package that modifies the configuration files
of the group of Debian packages of interest.  Then dpkg and the rest
of the package management system will see that the files have been
modified by the local sysadmin and will not try to overwrite them when
those packages are upgraded.

11.6.  How do I override a file installed by a package so that a different
       version can be used instead?

Suppose a sysadmin or local user wishes to use a program login-local
rather than the program login provided by the Debian login package. Do
not:

o  Overwrite /bin/login with login-local.

The package management system will not know about this change, and
will simply overwrite your custom /bin/login whenever login (or any
package that provides /bin/login) is installed or updated.  Rather, do

o  Execute dpkg-divert --divert /bin/login.debian /bin/login in order
   to cause all future installations of the Debian login packages to
   write the file /bin/login to /bin/login.debian instead.

o  Then execute cp login-local /bin/login to move your own
   locally-built program into place.

Some details are given in the usage statement for dpkg-divert (which
can be viewed using the command dpkg-divert --help). Additional
details are given in the Debian programmer's manual.

11.7.  How can I have my locally-built package included in the list of
       available packages that the package management system knows about?

You can do this in either of two ways:

o  Use dselect, and reselect the access method. You will be asked for a
   directory where your local packages reside.

o  Execute the command dpkg-scanpackages BIN_DIR OVERRIDE_FILE
   [PATHPREFIX] > Packages.new where:

   -  BIN-DIR is a directory where Debian archive files (which usually
      have an extension of .deb) are stored.

   -  OVERRIDE_FILE is a file that is edited by the distribution
      maintainers and is usually stored on a Debian FTP archive at
      indices/override.main.gz for the Debian packages in the main
      distribution.
   -  PATHPREFIX is an optional string that can be prepended to the
      Packages.new file being produced.

   Once you have built the file Packages.new, tell the package
   management system about it by using the command dpkg --update-avail
   Packages.new.


11.8.  Some users like mawk, others like gawk; some like vim, others like
       elvis; some like trn, others like tin; how does Debian support
       diversity?

There are several cases where two packages provide two different
versions of a program, both of which provide the same core
functionality.  Users might prefer one over another out of habit, or
because the user interface of one package is somehow more pleasing
than the interface of another.  Other users on the same system might
make a different choice.

Debian uses a virtual package system to allow system administrators to
choose (or let users choose) their favorite tools when there are two
or more that provide the same basic functionality, yet satisfy package
dependency requirements without specifying a particular package.

For example, there might exist two different versions of newsreaders
on a system.  The news server package might 'recommend' that there
exist some news reader on the system, but the choice of tin or trn is
left up to the individual user.  This is satisfied by having both the
tin and trn packages provide the virtual package news-reader.  Which
program is invoked is determined by a link pointing from a file with
the virtual package name /etc/alternatives/news-reader to the selected
file, e.g., /usr/bin/trn.

A single link is insufficient to support full use of an alternate
program; normally, manual pages, and possibly other supporting files
must be selected as well.  The Perl script update-alternatives
provides a way of ensuring that all the files associated with a
specified package are selected as a system default.


12.  Getting support for Debian Linux



12.1.  What other documentation exists on and for a Debian system?

o  Installation instructions for the current release: see (
   http://www.debian.org/1.1/install.html ) .
o  dpkg programmer's manual and Debian policy manual

   --  The dpkg programmer's manual (
       ftp://ftp.debian.org/debian/doc/package-developer/programmer.ps.gz )
       is the primary documentation on the technical aspects of
       creating Debian binary and source packages.

       The Debian policy manual (
       ftp://ftp.debian.org/debian/doc/package-developer/policy.ps.gz )
       documents the policy requirements for a package to be included
       in Debian.

       These documents are also included in the latest dpkg-dev package.

o  Documentation on installed Debian packages: Most packages have files
   that are unpacked into /usr/doc/ and /usr/doc/examples/.

o  Documentation on the Linux project: The Debian package doc-
   linux_VVV-RRR.deb installs all of the most recent versions of the
   HOWTOs and mini-HOWTOs from the Linux Documentation Project. This
   package is in the stable/binary-all/doc/ section in the FTP
   archives.

o  Unix-style 'man' pages: Most commands have manual pages written in
   the style of the original Unix 'man' files. They are referenced by
   the section of the 'man' directory where they reside: e.g., foo(3)
   refers to a manual page which resides in /usr/man/man3/, and it can
   be called by executing the command: man 3 foo, or just man foo if
   section 3 is the only one containing a page on foo. One can learn
   which directory of /usr/man/ contains a certain manual page by
   executing man -w foo.

   New Debian users should note that the 'man' pages of many general
   system commands are not available until they install these packages
   (both of which are normally stored in the stable/binary-all/doc/
   directory of the Debian FTP archive:
   -  manpages_VVV-RRR.deb (see support for non-English languages (5.11)).

   -  man_VVV-RRR.deb, which contains the man program itself, and other
      programs for manipulating the manual pages.

o  GNU-style 'info' pages: User documentation for many commands,
   particularly GNU tools, is available not in 'man' pages, but in
   'info' files which can be read by the GNU tool info or by running
   M-x info within GNU Emacs. Its main advantage over the original
   'man' pages are that it is a hypertext system.  It does not require
   the WWW, however; info can be run from a plain text console.  It
   was designed by Richard Stallman and preceded the WWW. The program
   that manipulates `info' files is installed as a separate package
   info_VVV-RRR.deb, usually stored in the directory
   stable/binary-all/doc/ on the FTP archive.


12.2.  Are there any on-line resources for discussing Debian?

There are several Debian-related mailing lists:

o  [e-mail] (moderated).  (Usually) major system
   announcements.  On average, fewer than one message per week are posted
   here.
o  [e-mail]. Announcements of new package uploads
   for the Debian system. This list may carry several announcements in a
   day.
o  [e-mail].  A mailing list where users can ask for
   and receive advice on the use or configuration of Debian packages
   or other aspects of Debian Linux. This list is an invaluable learning
   resource; there can be 50 messages a day or more on this list.
o  [e-mail]. This list is for those involved in
   porting Debian software to the SPARC platform.
o  [e-mail].  This list is for those involved in
   porting Debian software to DEC alpha platforms.
o  [e-mail]. This list is for those involved in porting
   Debian software to Motorola 680x0 platforms; currently this means the
   Atari and Amiga only.
o  [e-mail].

To subscribe to debian-X (for X in announce, changes, user, talk),
send mail to [e-mail] with the word subscribe
in the Subject: header.  If you have a forms-capable World Wide Web
browser, you can subscribe to debian-announce and debian-user by using
the WWW form( http://www.rahul.net/perens/Debian/MailingLists.html ) .
You can also un-subscribe using that form.  The list manager's e-mail
address is [e-mail]

Archives of the Debian mailing lists are available via WWW at (
http://www.debian.org/Lists-Archives/ ) and via FTP from (
ftp://ftp.debian.org/debian/debian-lists/ ) .

Users can address questions to individual package maintainers, since
their e-mail addresses are provided in the Debian control file (see
section Debian control file (6.4)) that is included within each
package.  One can also learn the maintainers' names and e-mail
addresses by searching the Packages file, since this file is just a
concatenation of all the available package control files in a
particular directory tree. To extract a control file from a particular
Debian package, use the command,


   dpkg --info packageName_VVV-RRR.deb


Another related mailing list, debiangame, is being run by Gary Moore (
( mailto:[e-mail] ) ) at the University of Washington.  As the
name suggests, it is devoted to the discussion of games that have been
(or might be) packaged for Debian.  To subscribe, send mail to
[e-mail], putting in the message body:

     subscribe debiangame FirstName LastName


Both FirstName and LastName are required for ListProc.

Users should post non-Debian-specific questions to one of the Linux
Usenet groups, which are named comp.os.linux.* or linux.*.
Specialized Systems Consultants (a.k.a. SSC) maintains a list of
Linux, Unix, X, and networking newsgroups (
http://www.ssc.com/linux/news.html ) on their WWW site.


12.3.  What is the code of conduct for the mailing lists?

When using the Debian mailing lists, please follow these rules:

o  Do not flame; it is not polite.  Besides the people developing
   Debian are all volunteers, donating their time, energy and money in
   an attempt to bring the Debian project together.

o  Do not use foul language; some people receive the lists via packet
   radio, where swear words are illegal.

o  Make sure that you are using the proper list.

o  Do not try posting unless you are subscribed.  Posting by
   non-subscribers was turned off to make the mailing lists
   usable. Thus, only postings from e-mail addresses matching those of
   a subscriber are accepted.  If you often post from other addresses
   than the one you subscribe with, mail the list manager
   [e-mail] with the subject please add subscriber
   alias.

o See section reporting bugs (13.2) for notes on reporting bugs.


12.4.  Is there a quick way to search for information on Debian GNU/Linux?

There are a variety of search engines that serve documentation related
to Debian.

o  Verism's search site.  To obtain information on how to submit a
   debian bug report, enter the words debian bug submit and search for
   all of these words.

o  DejaNews news search service.  To find out what experiences people
   have had with finding drivers for Western Digital controllers, try
   searching on this phrase:


       linux & WD

   This tells DejaNews to report any postings containing both the
   string linux AND the string WD When I used it, I discovered that my
   WD card (which I have only had for 6 months) has been declared
   outmoded by Adaptec, now that they have bought WD.  So there are no
   drivers available.  (Bless Adaptec's hearts.)

o  The AltaVista Search Engine can also be used to search Usenet
   (although it appears to be not quite as up to date as DejaNews).
   For example, searching on the string "cgi-perl" gives a more
   detailed explanation of this package than the brief description
   field in its control file.


13.  The Debian Bug Report System


13.1.  Are there logs of known bugs?

The Debian Linux distribution has a bug tracking system which files
details of bugs reported by users and developers. Each bug is given a
number, and is kept on file until it is marked as having been dealt
with.

Copies of this information are available at (
http://www.cl.cam.ac.uk/users/iwj10/debian-bugs/ ) and (
http://www.debian.org/Bugs/ ) , but the latter is not up-to-date at
present.

A mail server provides access to the bug tracking system database via
e-mail.  In order to get the instructions send an e-mail to
[e-mail] with "help" in the body.


13.2.  How do I report a bug in Debian?

If you have found a bug in Debian, please read the instructions for
reporting a bug in Debian.  These instructions can be obtained in one
of several ways:

o  By anonymous ftp.  Debian mirror sites contain the instructions in
   the file doc/bug-reporting.txt.

o  From the WWW.  A copy of the instructions is shown at (
   http://www.cl.cam.ac.uk/users/iwj10/debian-bugs/Reporting.html )

o  On any Debian system with the doc-debian package installed.  The
   instructions are in the file /usr/doc/debian/bug-reporting.txt.

Use these mail addresses for bugs:

o  [e-mail]: for general bug reports.  Expect to get
   an automatic acknowledgement of your bug report.  It will also be
   automatically given a bug tracking number, entered into the bug log
   and forwarded to the debian-devel mailing list.

o  [e-mail]: to send bug reports to the maintainer
   only. It will not be forwarded to the debian-devel mailing
   list. For example, if one were to identify a bug that was common to
   many programs, then rather than entering dozens of bug reports, one
   might prefer to send individual bugs to maintonly, then send a
   summary report to debian-devel.

o  [e-mail]: to submit bug reports to the bug log only,
   without having them sent either to debian-devel or to the maintainer.


14.  Contributing to the Debian project

Donations of time (to develop new packages, maintain existing
packages, or provide user support), resources (to mirror the FTP and
WWW archives), and money (to pay for new testbeds as well as hardware
for the archives) can help the project.


14.1.  How can I become a Debian software developer?

The development of Debian is open to all, and new users with the right
skills and/or the willingness to learn are needed to maintain existing
packages which have been orphaned by their previous maintainers, to
develop new packages, and to provide user support.

To develop a Debian package, you should:

o  (of course) download Debian and install it on your system.

o  find a program you would like to package that is not
   presently part of Debian.  In this regard, the Work
   Needing and Prospective Packages document (available as
   /debian/doc/package-developer/prospective-packages.txt at the
   Debian FTP server) should serve as a useful guide.

o  Subscribe to debian-devel.
   To do this execute


               mail [e-mail] -s Subscribe


   That is, send mail to the above address with the subject set to
   'Subscribe'.

o  Set up your PGP key.

   Install the PGP package; read /usr/doc/pgp/; generate a
   public-secret key pair by typing pgp -kg and answering the
   questions.  (Be prepared to write some arbitrary text when asked.
   PGP generates its true random numbers by measuring the intervals
   between your keystrokes.)

o  Shake hands with the project administration:
   Send an e-mail to [e-mail]

   with this content:
   -  what you have done,
   -  who you are,
   -  request for an account on master,
   -  request to be subscribed to debian-private (the developers-only
      mailing list).
   -  your PGP key, obtained by executing 'pgp -kxa'.

o  Make the programs:  .deb, .diff, .tar.gz, .changes.

   Use the hello*deb and dpkg*deb packages as guides, and read the
   policy manual and dpkg programmers manual.

o  Upload the files to

   -  ftp://master.debian.org/home/Debian/ftp/private/project/Incoming/
      using your user-name and password, or
   -  ftp://ftp.chiark.greenend.org.uk/ using anonymous ftp.
      For instructions to upload to chiark, read this file at chiark:
      /pub/debian/private/project/README.how-to-upload. chiark then
      sends the files it gets to master.


14.1.1 Are there additional information resources for developers?

Besides debian-devel, there are these mailing lists:

o  The SPARC port developers list:  [e-mail].
o  The Alpha port developers list: [e-mail].
o  The Motorola 680x0 port developers list: [e-mail].
o  The dpkg development list: [e-mail].
o  Debian for Hams: [e-mail].
o  Debian package maintainers only: [e-mail].

To subscribe to debian-devel, or other developers' list, send a
message to [e-mail] with a one-line explanation of
what you would like to test or develop.


14.2.  How can I contribute resources to the Debian project?

Since the project aims to make a substantial body of software rapidly
and easily accessible throughout the globe, mirrors are urgently
needed. It is desirable but not absolutely necessary to mirror all of
the archive. The current components amount to just over 1.4 GBytes,
broken down roughly as follows:

o  non-free: 100 MBytes.
o  contrib: 50 MBytes.
o  Debian-1.2 (including updates): 650 MBytes.
o  unstable: 200 MBytes.
o  mailing list archives: 20 MBytes.

Most of the mirroring is accomplished entirely automatically by
scripts, without any human intervention.  However, the occasional
glitch or system change occurs which requires human intervention.

If you have a high-speed connection to the Internet, the resources to
mirror all or part of the distribution, and are willing to take the
time (or find someone) who can provide regular maintenance of the
system, then please contact Bruce Perens (E-Mail: [e-mail];
Voice (work): 510-215-3502).



14.3.  How can I contribute financially to the Debian project?

One can make individual donations to one of two organizations that are
critical to the development of the Debian project.

14.3.1 Software in the Public Interest

Software in the Public Interest (SPI) is a non-profit organization
formed when FSF withdrew their sponsorship of Debian.  We are
currently incorporating as an IRS 501(c)(3) non-profit
organization. The purpose of the organization is to develop and
distribute free software. Our goals are very much like those of FSF,
and we encourage programmers to use the GNU General Public License on
their programs. However, we have a slightly different focus in that we
are building and distributing a Linux system that diverges in many
technical details from the GNU system planned by FSF.  We still
communicate with FSF, and we cooperate in sending them changes to GNU
software and in asking our users to donate to FSF and the GNU project.
SPI can be reached at:

o  E-Mail: [e-mail]

o  Postal address:


               Software in the Public Interest
               P.O. Box 70152
               Pt. Richmond, CA 94807-0152

o  Phone: [phone] (Bruce Perens at work)


14.3.2 Free Software Foundation

At this time there is no formal connection between Debian and the Free
Software Foundation.  However, the Free Software Foundation is
responsible for some of the most important software components in
Debian, including the GNU C compiler, GNU Emacs, and much of the C
run-time library that is used by all programs on the system. FSF
pioneered much of what free software is today: they wrote the the
General Public License that is used on much of the Debian software,
and they invented the "GNU" project to create an entirely free Unix
system. Debian should be considered a descendent of the GNU system.

When you make a donation to FSF, please be sure to tell them that you
are a Debian user. Please contact them at:

o  E-mail: [e-mail]
o  Postal address:

           Free Software Foundation
           59 Temple Place - Suite 330
           Boston, MA  02111-1307
           USA

o  Phone number: [phone]
o  Fax (including Japan): [phone]
o  Free Dial Fax (in Japan): 0031-13-2473 (KDD), 0066-3382-0158 (IDC)
o  On the WWW :  ( http://www.gnu.ai.mit.edu/ )



15.  Redistributing Debian GNU/Linux in a commercial product


15.1.  Can I make and sell Debian CDs?

Go ahead. You do not need permission to distribute anything we have
released, so that you can master your CD as soon as the beta-test
ends.  You do not have to pay us anything.  We will, however, publish
a list of CD manufacturers who donate money, software, and time to the
Debian project, and we will encourage users to buy from manufacturers
who donate, so it is good advertising to make donations.  Of course
all CD manufacturers must honor the licenses of the programs in
Debian. For example, many of the programs are licensed under the GPL,
which requires you to distribute their source code.

15.2.  Can Debian be packaged with non-free software?

Yes. While all the main components of Debian are free software, we
provide a non-free directory for programs that are not freely
redistributable. CD manufacturers may be able to distribute the
programs we have placed in that directory, depending on the license
terms or their private arrangements with the authors of those software
packages.  CD manufacturers can also distribute the non-free software
they get from other sources on the same CD. This is nothing new: free
and commercial software are distributed on the same CD by many
manufacturers now.  Of course we still encourage software authors to
release the programs they write as free software.


15.3.  I am making a special Linux distribution for a vertical market. Can
       I use Debian GNU/Linux for the guts of a Linux system and add my own
       applications on top of it?

Yes. For example, one person is building a Linux for Hams
distribution, with specialized programs for Radio Amateurs. He is
starting with Debian as the base system, and adding programs to
control the transmitter, track satellites, etc. All of the programs he
adds are packaged with the Debian package system so that his users
will be able to upgrade easily when he releases subsequent CDs.

Debian also provides a mechanism to allow developers and system
administrators to install local versions of selected files in such a
way that they will not be overwritten when other packages are
upgraded.  This is discussed further in the question on diversions
(11.6).


15.4.  Can I put my commercial program in a Debian package so that it
       installs effortlessly on any Debian system?

Go right ahead. The package tool is free software.



16.  What kind of changes should I expect to see in the next major release
     of Debian Linux?


16.1.  A New Approach to the Boot Floppies

In order to accommodate all of the hardware for which Linux drivers
have been written, yet still provide boot-floppies that can fit on a
5.25-inch disk, Debian 1.2 will provide a mechanism to access all
drivers that can be modularized as modules. (This work is partially
done.)

The default kernel has no IDE, no SCSI, little else. When the user
sets up the system, it builds a RAM disk image that is loaded at boot
time.  The script on the RAM disk loads the modules for your local
hardware configuration _before_ it mounts the root. Some things that
still are not modularized are in the default kernel.

The stripped-down kernel and the compressed installation root
filesystem fit on one 1200K floppy and run fine that way. The floppy
also contains a few of the most popular modules, and you get to feed
it more floppies (or a CD) containing other modules depending on your
configuration.

No-floppy bootstrap should be possible for systems with 8MByte RAM and
a CD or DOS hard disk. One-floppy NFS bootstrap should be possible.
See /usr/src/linux/Documentation/initrd.txt .


16.2.  Increased security

Debian will be equipped with the Shadow password suite of programs and
library routines which hide the plain text of the password file from
all users except root and provide for terminal access control, and
user and group administration.  For details, see (
http://sunsite.unc.edu/mdw/HOWTO/Shadow-Password-HOWTO.html ) .  This
document is of course also included along with all the HOWTOs in the
Debian doc-linux package.

Most of the relevant Debian utilities have been modified to make them
support shadow passwords. This includes the default login utility, as
well as vipw and vigr. The xdm X11 login utility and the adduser
script will be made shadow aware as well.  In addition, there will be
minor changes to the shadow packages themselves.

In addition, the Linux library of Pluggable Authentication Modules ( (
http://parc.power.net/morgan/Linux-PAM/ ) ; a.k.a.  libpam) that allow
sysadmins to choose authorization modes on an application-specific
basis will be available, and initially set to authenticate via shadow
password.


16.3.  More Support for non-English users

Debian already has some support for non-English users (5.11). We hope
to find people who provide support for even more languages.

Some programs already support internationalization, so we need message
catalogs. Many programs still must be internationalized.


16.4.  More architectures

Currently a complete Debian release is only available for the i386
architecture. Complete Debian system on other architectures are
expected soon.