Installation
* Requirements:: Software needed to build and run Guix.
+* Running the Test Suite:: Testing Guix.
* Setting Up the Daemon:: Preparing the build daemon's environment.
* Invoking guix-daemon:: Running the build daemon.
* Invoking guix refresh:: Updating package definitions.
* Invoking guix lint:: Finding errors in package definitions.
* Invoking guix environment:: Setting up development environments.
+* Invoking guix publish:: Sharing substitutes.
GNU Distribution
* Base Services:: Essential system services.
* Networking Services:: Network setup, SSH daemon, etc.
* X Window:: Graphical display.
+* Various Services:: Other services.
Packaging Guidelines
-* Software Freedom:: What may go into the distribution.
-* Package Naming:: What's in a name?
-* Version Numbers:: When the name is not enough.
-* Python Modules:: Taming the snake.
-* Perl Modules:: Little pearls.
-* Fonts:: Fond of fonts.
+* Software Freedom:: What may go into the distribution.
+* Package Naming:: What's in a name?
+* Version Numbers:: When the name is not enough.
+* Python Modules:: Taming the snake.
+* Perl Modules:: Little pearls.
+* Fonts:: Fond of fonts.
@end detailmenu
@end menu
instead, you want to install the complete GNU operating system,
@pxref{System Installation}.
-The build procedure for Guix is the same as for other GNU software, and
-is not covered here. Please see the files @file{README} and
-@file{INSTALL} in the Guix source tree for additional details.
-
@menu
+* Binary Installation:: Getting Guix running in no time!
* Requirements:: Software needed to build and run Guix.
+* Running the Test Suite:: Testing Guix.
* Setting Up the Daemon:: Preparing the build daemon's environment.
* Invoking guix-daemon:: Running the build daemon.
@end menu
+@node Binary Installation
+@section Binary Installation
+
+This section describes how to install Guix on an arbitrary system from a
+self-contained tarball providing binaries for Guix and for all its
+dependencies. This is often quicker than installing from source, which
+is described in the next sections. The only requirement is to have
+GNU@tie{}tar and Xz.
+
+Installing goes along these lines:
+
+@enumerate
+@item
+Download the binary tarball from
+@code{ftp://alpha.gnu.org/gnu/guix/guix-binary-@value{VERSION}.@var{system}.tar.xz}@footnote{As
+usual, make sure to download the associated @file{.sig} file and to
+verify the authenticity of the tarball against it!}, where @var{system}
+is @code{x86_64-linux} for an @code{x86_64} machine already running the
+kernel Linux, and so on.
+
+@item
+As @code{root}, run:
+
+@example
+# cd /
+# tar xf guix-binary-@value{VERSION}.@var{system}.tar.xz
+@end example
+
+This creates @file{/gnu/store} (@pxref{The Store}), @file{/var/guix},
+and @file{/root/.guix-profile}. @file{/root/.guix-profile} is a
+ready-to-use profile for @code{root} where Guix is installed.
+
+Do @emph{not} unpack the tarball on a working Guix system since that
+would overwrite its own essential files.
+
+@item
+Set up the daemon as explained below (@pxref{Setting Up the Daemon}), and
+run it:
+
+@example
+# /root/.guix-profile/bin/guix-daemon --build-users-group=guix-builder
+@end example
+
+@item
+Make the @command{guix} command available to other users on the machine,
+for instance with:
+
+@example
+# mkdir -p /usr/local/bin
+# cd /usr/local/bin
+# ln -s /root/.guix-profile/bin/guix
+@end example
+@end enumerate
+
+And that's it!
+
+The @code{guix} package must remain available in @code{root}'s
+profile, or it would become subject to garbage collection---in which
+case you would find yourself badly handicapped by the lack of the
+@command{guix} command.
+
+The tarball in question can be (re)produced simply by running the
+following command in the Guix source tree:
+
+@example
+make guix-binary.@var{system}.tar.xz
+@end example
+
+
@node Requirements
@section Requirements
+This section lists requirements when building Guix from source. The
+build procedure for Guix is the same as for other GNU software, and is
+not covered here. Please see the files @file{README} and @file{INSTALL}
+in the Guix source tree for additional details.
+
GNU Guix depends on the following packages:
@itemize
Note that @code{--disable-daemon} is not required if
your goal is to share the store with Nix.
+@node Running the Test Suite
+@section Running the Test Suite
+
+After a successful @command{configure} and @code{make} run, it is a good
+idea to run the test suite. It can help catch issues with the setup or
+environment, or bugs in Guix itself---and really, reporting test
+failures is a good way to help improve the software. To run the test
+suite, type:
+
+@example
+make check
+@end example
+
+Test cases can run in parallel: you can use the @code{-j} option of
+GNU@tie{}make to speed things up. The first run may take a few minutes
+on a recent machine; subsequent runs will be faster because the store
+that is created for test purposes will already have various things in
+cache.
+
+Upon failure, please email @email{bug-guix@@gnu.org} and attach the
+@file{test-suite.log} file. When @file{tests/@var{something}.scm}
+fails, please also attach the @file{@var{something}.log} file available
+in the top-level build directory. Please specify the Guix version being
+used as well as version numbers of the dependencies
+(@pxref{Requirements}) in your message.
+
@node Setting Up the Daemon
@section Setting Up the Daemon
daemon (@i{via} remote procedure calls) to instruct it what to do.
The following sections explain how to prepare the build daemon's
-environment.
+environment. Also @ref{Substitutes}, for information on how to allow
+the daemon to download pre-built binaries.
@menu
* Build Environment Setup:: Preparing the isolated build environment.
done
@end example
-The @file{/gnu/store} directory (or whichever was specified with the
-@code{--with-store-dir} option) must have ownership and permissions as
-follows:
-
-@example
-# chgrp guix-builder /gnu/store
-# chmod 1775 /gnu/store
-@end example
-
@noindent
The @code{guix-daemon} program may then be run as @code{root} with:
Each @var{package} may specify either a simple package name, such as
@code{guile}, or a package name followed by a hyphen and version number,
-such as @code{guile-1.8.8}. If no version number is specified, the
+such as @code{guile-1.8.8} or simply @code{guile-1.8} (in the latter
+case, the newest version prefixed by @code{1.8} is selected.)
+
+If no version number is specified, the
newest available version will be selected. In addition, @var{package}
may contain a colon, followed by the name of one of the outputs of the
package, as in @code{gcc:doc} or @code{binutils-2.22:lib}
@itemx -u [@var{regexp} @dots{}]
Upgrade all the installed packages. If one or more @var{regexp}s are
specified, upgrade only installed packages whose name matches a
-@var{regexp}.
+@var{regexp}. Also see the @code{--do-not-upgrade} option below.
Note that this upgrades package to the latest version of packages found
in the distribution currently installed. To update your distribution,
you should regularly run @command{guix pull} (@pxref{Invoking guix
pull}).
+@item --do-not-upgrade[=@var{regexp} @dots{}]
+When used together with the @code{--upgrade} option, do @emph{not}
+upgrade any packages whose name matches a @var{regexp}. For example, to
+upgrade all packages in the current profile except those containing the
+substring ``emacs'':
+
+@example
+$ guix package --upgrade . --do-not-upgrade emacs
+@end example
+
@item --roll-back
Roll back to the previous @dfn{generation} of the profile---i.e., undo
the last transaction.
@item --search=@var{regexp}
@itemx -s @var{regexp}
-List the available packages whose synopsis or description matches
+List the available packages whose name, synopsis, or description matches
@var{regexp}. Print all the meta-data of matching packages in
@code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
GNU recutils manual}).
@item --list-available[=@var{regexp}]
@itemx -A [@var{regexp}]
-List packages currently available in the software distribution
+List packages currently available in the distribution for this system
(@pxref{GNU Distribution}). When @var{regexp} is specified, list only
installed packages whose name matches @var{regexp}.
specified duration match. For instance, @code{--delete-generations=1m}
deletes generations that are more than one month old.
-If the current generation matches, it is deleted atomically---i.e., by
-switching to the previous available generation. Note that the zeroth
-generation is never deleted.
+If the current generation matches, it is @emph{not} deleted. Also, the
+zeroth generation is never deleted.
Note that deleting generations prevents roll-back to them.
Consequently, this command must be used with care.
@cindex garbage collector
Packages that are installed but not used may be @dfn{garbage-collected}.
The @command{guix gc} command allows users to explicitly run the garbage
-collector to reclaim space from the @file{/gnu/store} directory.
+collector to reclaim space from the @file{/gnu/store} directory. It is
+the @emph{only} way to remove files from @file{/gnu/store}---removing
+files or directories manually may break it beyond repair!
The garbage collector has a set of known @dfn{roots}: any file under
@file{/gnu/store} reachable from a root is considered @dfn{live} and
@code{#:python} parameter.
@end defvr
+@defvr {Scheme Variable} haskell-build-system
+This variable is exported by @code{(guix build-system haskell)}. It
+implements the Cabal build procedure used by Haskell packages, which
+involves running @code{runhaskell Setup.hs configure
+--prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
+Instead of installing the package by running @code{runhaskell Setup.hs
+install}, to avoid trying to register libraries in the read-only
+compiler store directory, the build system uses @code{runhaskell
+Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
+addition, the build system generates the package documentation by
+running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
+is passed. Optional Haddock parameters can be passed with the help of
+the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
+not found, the build system looks for @code{Setup.lhs} instead.
+
+Which Haskell compiler is used can be specified with the @code{#:haskell}
+parameter which defaults to @code{ghc}.
+@end defvr
+
Lastly, for packages that do not need anything as sophisticated, a
``trivial'' build system is provided. It is trivial in the sense that
it provides basically no support: it does not pull any implicit inputs,
processes.
@item
-When a package or derivation is unquoted inside a gexp, the result is as
-if its output file name had been introduced.
+When a high-level object such as a package or derivation is unquoted
+inside a gexp, the result is as if its output file name had been
+introduced.
@item
Gexps carry information about the packages or derivations they refer to,
processes that use them.
@end itemize
+Actually this mechanism is not limited to package and derivation
+objects; @dfn{compilers} able to ``lower'' other high-level objects to
+derivations can be defined, such that these objects can also be inserted
+into gexps. Another useful type of high-level object that can be
+inserted in a gexp is @dfn{local files}, which allows files from the
+local file system to be added to the store and referred to by
+derivations and such (see @code{local-file} below.)
+
To illustrate the idea, here is an example of a gexp:
@example
#~(begin
(mkdir #$output)
(chdir #$output)
- (symlink (string-append #$coreutils "/bin/ls")
+ (symlink (string-append #$coreutils "/bin/ls")
"list-files")))
@end example
@table @code
@item #$@var{obj}
@itemx (ungexp @var{obj})
-Introduce a reference to @var{obj}. @var{obj} may be a package or a
+Introduce a reference to @var{obj}. @var{obj} may have one of the
+supported types, for example a package or a
derivation, in which case the @code{ungexp} form is replaced by its
output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
-If @var{obj} is a list, it is traversed and any package or derivation
-references are substituted similarly.
+If @var{obj} is a list, it is traversed and references to supported
+objects are substituted similarly.
If @var{obj} is another gexp, its contents are inserted and its
dependencies are added to those of the containing gexp.
If @var{obj} is another kind of object, it is inserted as is.
-@item #$@var{package-or-derivation}:@var{output}
-@itemx (ungexp @var{package-or-derivation} @var{output})
+@item #$@var{obj}:@var{output}
+@itemx (ungexp @var{obj} @var{output})
This is like the form above, but referring explicitly to the
-@var{output} of @var{package-or-derivation}---this is useful when
-@var{package-or-derivation} produces multiple outputs (@pxref{Packages
-with Multiple Outputs}).
+@var{output} of @var{obj}---this is useful when @var{obj} produces
+multiple outputs (@pxref{Packages with Multiple Outputs}).
@item #+@var{obj}
@itemx #+@var{obj}:output
The other arguments are as for @code{derivation} (@pxref{Derivations}).
@end deffn
+@deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
+ [#:recursive? #t]
+Return an object representing local file @var{file} to add to the store; this
+object can be used in a gexp. @var{file} will be added to the store under @var{name}--by
+default the base name of @var{file}.
+
+When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
+designates a flat file and @var{recursive?} is true, its contents are added, and its
+permission bits are kept.
+
+This is the declarative counterpart of the @code{interned-file} monadic
+procedure (@pxref{The Store Monad, @code{interned-file}}).
+@end deffn
+
@deffn {Monadic Procedure} gexp->script @var{name} @var{exp}
Return an executable script @var{name} that runs @var{exp} using
@var{guile} with @var{modules} in its search path.
@deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
Return as a monadic value a derivation that builds a text file
containing all of @var{text}. @var{text} may list, in addition to
-strings, packages, derivations, and store file names; the resulting
-store file holds references to all these.
+strings, objects of any type that can be used in a gexp: packages,
+derivations, local file objects, etc. The resulting store file holds
+references to all these.
This variant should be preferred over @code{text-file} anytime the file
to create will reference items from the store. This is typically the
* Invoking guix refresh:: Updating package definitions.
* Invoking guix lint:: Finding errors in package definitions.
* Invoking guix environment:: Setting up development environments.
+* Invoking guix publish:: Sharing substitutes.
@end menu
@node Invoking guix build
@example
guix import nix ~/path/to/nixpkgs libreoffice
@end example
+
+@item hackage
+@cindex hackage
+Import meta-data from Haskell community's central package archive
+@uref{https://hackage.haskell.org/, Hackage}. Information is taken from
+Cabal files and includes all the relevant information, including package
+dependencies.
+
+Specific command-line options are:
+
+@table @code
+@item --no-test-dependencies
+@itemx -t
+Do not include dependencies only required to run the test suite.
+@end table
+
+The command below imports meta-data for the latest version of the
+@code{HTTP} Haskell package without including test dependencies:
+
+@example
+guix import hackage -t HTTP
+@end example
+
+A specific package version may optionally be specified by following the
+package name by a hyphen and a version number as in the following example:
+
+@example
+guix import hackage mtl-2.1.3.1
+@end example
+
+Currently only indentation structured Cabal files are supported.
@end table
The structure of the @command{guix import} code is modular. It would be
names, as in this example:
@example
-guix refresh -u emacs idutils
+guix refresh -u emacs idutils gcc-4.8.4
@end example
@noindent
It also supports all of the common build options that @command{guix
build} supports (@pxref{Invoking guix build, common build options}).
+@node Invoking guix publish
+@section Invoking @command{guix publish}
+
+The purpose of @command{guix publish} is to enable users to easily share
+their store with others. When @command{guix publish} runs, it spawns an
+HTTP server which allows anyone with network access to obtain
+substitutes from it. This means that any machine running Guix can also
+act as if it were a build farm, since the HTTP interface is
+Hydra-compatible.
+
+For security, each substitute is signed, allowing recipients to check
+their authenticity and integrity (@pxref{Substitutes}). Because
+@command{guix publish} uses the system's signing key, which is only
+readable by the system administrator, it must run as root.
+
+The general syntax is:
+
+@example
+guix publish @var{options}@dots{}
+@end example
+
+Running @command{guix publish} without any additional arguments will
+spawn an HTTP server on port 8080:
+
+@example
+guix publish
+@end example
+
+Once a publishing server has been authorized (@pxref{Invoking guix
+archive}), the daemon may download substitutes from it:
+
+@example
+guix-daemon --substitute-urls=http://example.org:8080
+@end example
+
+The following options are available:
+
+@table @code
+@item --port=@var{port}
+@itemx -p @var{port}
+Listen for HTTP requests on @var{port}.
+
+@item --repl[=@var{port}]
+@itemx -r [@var{port}]
+Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
+Reference Manual}) on @var{port} (37146 by default).
+@end table
+
@c *********************************************************************
@node GNU Distribution
@chapter GNU Distribution
@code{<name-service-switch>} object. @xref{Name Service Switch}, for
details.
-@item @code{x509-certificates} (default: @var{nss-certs})
-This field's value must be a package containing X.509 certificates for
-so-called ``Certification Authorities'' (CAs) that is made available in
-the @file{/etc/ssl/certs} directory. Currently this directory is
-accessed by applications using either the GnuTLS library or the OpenSSL
-library.
-
-By default, certificates from
-@uref{https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS,
-Mozilla's Network Security Services} are used. These are the
-certificates shipped by Mozilla browsers and derivatives such as
-GNU@tie{}IceCat.
-
@item @code{services} (default: @var{%base-services})
A list of monadic values denoting system services. @xref{Services}.
@defvr {Scheme Variable} %base-file-systems
These are essential file systems that are required on normal systems,
-such as @var{%devtmpfs-file-system} (see below.) Operating system
-declarations should always contain at least these.
+such as @var{%devtmpfs-file-system} and @var{%immutable-store} (see
+below.) Operating system declarations should always contain at least
+these.
@end defvr
@defvr {Scheme Variable} %devtmpfs-file-system
@code{shm_open},, libc, The GNU C Library Reference Manual}).
@end defvr
+@defvr {Scheme Variable} %immutable-store
+This file system performs a read-only ``bind mount'' of
+@file{/gnu/store}, making it read-only for all the users including
+@code{root}. This prevents against accidental modification by software
+running as @code{root} or by system administrators.
+
+The daemon itself is still able to write to the store: it remounts it
+read-write in its own ``name space.''
+@end defvr
+
@defvr {Scheme Variable} %binary-format-file-system
The @code{binfmt_misc} file system, which allows handling of arbitrary
executable file types to be delegated to user space. This requires the
@node User Accounts
@subsection User Accounts
-User accounts are specified with the @code{user-account} form:
+User accounts and groups are entirely managed through the
+@code{operating-system} declaration. They are specified with the
+@code{user-account} and @code{user-group} forms:
@example
(user-account
(home-directory "/home/alice"))
@end example
+When booting or upon completion of @command{guix system reconfigure},
+the system ensures that only the user accounts and groups specified in
+the @code{operating-system} declaration exist, and with the specified
+properties. Thus, account or group creations or modifications made by
+directly invoking commands such as @command{useradd} are lost upon
+reconfiguration or reboot. This ensures that the system remains exactly
+as declared.
+
@deftp {Data Type} user-account
Objects of this type represent user accounts. The following members may
be specified:
@item @code{password} (default: @code{#f})
You would normally leave this field to @code{#f}, initialize user
passwords as @code{root} with the @command{passwd} command, and then let
-users change it with @command{passwd}.
+users change it with @command{passwd}. Passwords set with
+@command{passwd} are of course preserved across reboot and
+reconfiguration.
If you @emph{do} want to have a preset password for an account, then
this field must contain the encrypted password, as a string.
* Base Services:: Essential system services.
* Networking Services:: Network setup, SSH daemon, etc.
* X Window:: Graphical display.
+* Various Services:: Other services.
@end menu
@node Base Services
Return a service that runs libc's name service cache daemon (nscd) with
the given @var{config}---an @code{<nscd-configuration>} object.
Optionally, @code{#:name-services} is a list of packages that provide
-name service switch (NSS) modules needed by nscd.
+name service switch (NSS) modules needed by nscd. @xref{Name Service
+Switch}, for an example.
@end deffn
@defvr {Scheme Variable} %nscd-default-configuration
@end defvr
-@deffn {Monadic Procedure} syslog-service
-Return a service that runs @code{syslogd} with reasonable default
+@deffn {Monadic Procedure} syslog-service [#:config-file #f]
+Return a service that runs @code{syslogd}. If configuration file name
+@var{config-file} is not specified, use some reasonable default
settings.
@end deffn
[#:allow-empty-passwords? #f] [#:root-login? #f] @
[#:syslog-output? #t] [#:x11-forwarding? #t] @
[#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
- [#:public-key-authentication? #t] [#:initialize? #f]
+ [#:public-key-authentication? #t] [#:initialize? #t]
Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
@var{host-key} must designate a file containing the host key, and readable
only by root.
@deffn {Monadic Procedure} slim-service [#:allow-empty-passwords? #f] @
[#:auto-login? #f] [#:default-user ""] [#:startx] @
[#:theme @var{%default-slim-theme}] @
- [#:theme-name @var{%default-slim-theme-name}] @
- [#:sessions @var{%default-sessions}]
+ [#:theme-name @var{%default-slim-theme-name}]
Return a service that spawns the SLiM graphical login manager, which in
turn starts the X display server with @var{startx}, a command as returned by
@code{xorg-start-command}.
@var{theme} must be a gexp denoting the name of a directory containing the
theme to use. In that case, @var{theme-name} specifies the name of the
theme.
-
-Last, @var{session} is a list of @code{<session-type>} objects denoting the
-available session types that can be chosen from the log-in screen. The first
-one is chosen by default.
@end deffn
-@defvr {Scheme Variable} %default-sessions
-The list of default session types used by SLiM.
-@end defvr
-
-@defvr {Scheme Variable} %ratpoison-session-type
-Session type using the Ratpoison window manager.
-@end defvr
-
-@defvr {Scheme Variable} %windowmaker-session-type
-Session type using the WindowMaker window manager.
-@end defvr
-
-@defvr {Scheme Variable} %sawfish-session-type
-Session type using the Sawfish window manager.
-@end defvr
-
@defvr {Scheme Variable} %default-theme
@defvrx {Scheme Variable} %default-theme-name
The G-Expression denoting the default SLiM theme and its name.
resolutions---e.g., @code{((1024 768) (640 480))}.
@end deffn
+@node Various Services
+@subsubsection Various Services
+
+The @code{(gnu services lirc)} module provides the following service.
+
+@deffn {Monadic Procedure} lirc-service [#:lirc lirc] @
+ [#:device #f] [#:driver #f] [#:config-file #f] @
+ [#:extra-options '()]
+Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
+decodes infrared signals from remote controls.
+
+Optionally, @var{device}, @var{driver} and @var{config-file}
+(configuration file name) may be specified. See @command{lircd} manual
+for details.
+
+Finally, @var{extra-options} is a list of additional command-line options
+passed to @command{lircd}.
+@end deffn
+
+@code{(gnu services upower)} provides a power-management daemon:
+
+@deffn {Monadic Procedure} upower-service [#:upower @var{upower}] @
+ [#:watts-up-pro? #f] @
+ [#:poll-batteries? #t] @
+ [#:ignore-lid? #f] @
+ [#:use-percentage-for-policy? #f] @
+ [#:percentage-low 10] @
+ [#:percentage-critical 3] @
+ [#:percentage-action 2] @
+ [#:time-low 1200] @
+ [#:time-critical 300] @
+ [#:time-action 120] @
+ [#:critical-power-action 'hybrid-sleep]
+Return a service that runs @uref{http://upower.freedesktop.org/,
+@command{upowerd}}, a system-wide monitor for power consumption and battery
+levels, with the given configuration settings. It implements the
+@code{org.freedesktop.UPower} D-Bus interface, and is notably used by
+GNOME.
+@end deffn
+
+@code{(gnu services colord)} provides a color management service:
+
+@deffn {Monadic Procedure} colord-service [#:colord @var{colord}]
+Return a service that runs @command{colord}, a system service with a D-Bus
+interface to manage the color profiles of input and output devices such as
+screens and scanners. It is notably used by the GNOME Color Manager graphical
+tool. See @uref{http://www.freedesktop.org/software/colord/, the colord web
+site} for more information.
+@end deffn
+
@node Setuid Programs
@subsection Setuid Programs
@code{name-service-switch} field of @code{operating-system} declarations
(@pxref{operating-system Reference, @code{name-service-switch}}).
-@c See <http://0pointer.de/lennart/projects/nss-mdns/>.
+@cindex nss-mdns
+@cindex .local, host name lookup
As an example, the declaration below configures the NSS to use the
-@code{nss-mdns} back-end for host name lookups:
+@uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
+back-end}, which supports host name lookups over multicast DNS (mDNS)
+for host names ending in @code{.local}:
@example
(name-service-switch
(name "mdns")))))
@end example
+Note that, in this case, in addition to setting the
+@code{name-service-switch} of the @code{operating-system} declaration,
+@code{nscd-service} must be told where to find the @code{nss-mdns}
+shared library (@pxref{Base Services, @code{nscd-service}}). Since the
+@code{nscd} service is part of @var{%base-services}, you may want to
+customize it by adding this snippet in the operating system
+configuration file:
+
+@example
+(use-modules (guix) (gnu))
+
+(define %my-base-services
+ ;; Replace the default nscd service with one that knows
+ ;; about nss-mdns.
+ (map (lambda (mservice)
+ ;; "Bind" the MSERVICE monadic value to inspect it.
+ (mlet %store-monad ((service mservice))
+ (if (member 'nscd (service-provision service))
+ (nscd-service (nscd-configuration)
+ #:name-services (list nss-mdns))
+ mservice)))
+ %base-services))
+@end example
+
+@noindent
+@dots{} and then refer to @var{%my-base-services} instead of
+@var{%base-services} in the @code{operating-system} declaration.
+
The reference for name service switch configuration is given below. It
is a direct mapping of the C library's configuration file format, so
please refer to the C library manual for more information (@pxref{NSS
@cindex customization, of packages
@cindex package module search path
Users can store package definitions in modules with different
-names---e.g., @code{(my-packages emacs)}. These package definitions
+names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
+name and module name must match. @xref{Modules and the File System,,,
+guile, GNU Guile Reference Manual}, for details.} These package definitions
will not be visible by default. Thus, users can invoke commands such as
@command{guix package} and @command{guix build} have to be used with the
@code{-e} option so that they know where to find the package, or use the
@menu
-* Software Freedom:: What may go into the distribution.
-* Package Naming:: What's in a name?
-* Version Numbers:: When the name is not enough.
-* Python Modules:: Taming the snake.
-* Perl Modules:: Little pearls.
-* Fonts:: Fond of fonts.
+* Software Freedom:: What may go into the distribution.
+* Package Naming:: What's in a name?
+* Version Numbers:: When the name is not enough.
+* Python Modules:: Taming the snake.
+* Perl Modules:: Little pearls.
+* Fonts:: Fond of fonts.
@end menu
@node Software Freedom
HCoop / jackhill / guix / guix.git / blobdiff