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1 | \input texinfo |
2 | @c -*-texinfo-*- | |
3 | ||
4 | @c %**start of header | |
5 | @setfilename guix.info | |
6 | @documentencoding UTF-8 | |
f8348b91 | 7 | @settitle GNU Guix Reference Manual |
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8 | @c %**end of header |
9 | ||
10 | @include version.texi | |
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11 | |
12 | @copying | |
425b0bfc | 13 | Copyright @copyright{} 2012, 2013, 2014 Ludovic Courtès@* |
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14 | Copyright @copyright{} 2013 Andreas Enge@* |
15 | Copyright @copyright{} 2013 Nikita Karetnikov | |
16 | ||
17 | Permission is granted to copy, distribute and/or modify this document | |
18 | under the terms of the GNU Free Documentation License, Version 1.3 or | |
19 | any later version published by the Free Software Foundation; with no | |
20 | Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A | |
21 | copy of the license is included in the section entitled ``GNU Free | |
22 | Documentation License''. | |
23 | @end copying | |
568717fd | 24 | |
eeaf4427 | 25 | @dircategory Package management |
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26 | @direntry |
27 | * guix: (guix). Guix, the functional package manager. | |
e49951eb | 28 | * guix package: (guix)Invoking guix package |
eeaf4427 | 29 | Managing packages with Guix. |
e49951eb | 30 | * guix build: (guix)Invoking guix build |
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31 | Building packages with Guix. |
32 | @end direntry | |
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33 | |
34 | @titlepage | |
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35 | @title GNU Guix Reference Manual |
36 | @subtitle Using the GNU Guix Functional Package Manager | |
568717fd | 37 | @author Ludovic Courtès |
da7cabd4 | 38 | @author Andreas Enge |
acc08466 | 39 | @author Nikita Karetnikov |
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40 | |
41 | @page | |
42 | @vskip 0pt plus 1filll | |
43 | Edition @value{EDITION} @* | |
44 | @value{UPDATED} @* | |
45 | ||
7df7a74e | 46 | @insertcopying |
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47 | @end titlepage |
48 | ||
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49 | @contents |
50 | ||
51 | @c ********************************************************************* | |
52 | @node Top | |
f8348b91 | 53 | @top GNU Guix |
568717fd | 54 | |
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55 | This document describes GNU Guix version @value{VERSION}, a functional |
56 | package management tool written for the GNU system. | |
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57 | |
58 | @menu | |
59 | * Introduction:: What is Guix about? | |
bd5e766b | 60 | * Installation:: Installing Guix. |
eeaf4427 | 61 | * Package Management:: Package installation, upgrade, etc. |
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62 | * Programming Interface:: Using Guix in Scheme. |
63 | * Utilities:: Package management commands. | |
a1ba8475 | 64 | * GNU Distribution:: Software for your friendly GNU system. |
9bf3c1a7 | 65 | * Contributing:: Your help needed! |
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66 | |
67 | * Acknowledgments:: Thanks! | |
68 | * GNU Free Documentation License:: The license of this manual. | |
69 | * Concept Index:: Concepts. | |
70 | * Function Index:: Functions. | |
71 | @end menu | |
72 | ||
73 | @c ********************************************************************* | |
74 | @node Introduction | |
75 | @chapter Introduction | |
76 | ||
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77 | GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks'' |
78 | using the international phonetic alphabet (IPA).} is a functional | |
79 | package management tool for the GNU system. Package management consists | |
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80 | of all activities that relate to building packages from sources, |
81 | honoring their build-time and run-time dependencies, | |
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82 | installing packages in user environments, upgrading installed packages |
83 | to new versions or rolling back to a previous set, removing unused | |
84 | software packages, etc. | |
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85 | |
86 | @cindex functional package management | |
87 | The term @dfn{functional} refers to a specific package management | |
88 | discipline. In Guix, the package build and installation process is seen | |
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89 | as a function, in the mathematical sense. That function takes inputs, |
90 | such as build scripts, a compiler, and libraries, and | |
91 | returns an installed package. As a pure function, its result depends | |
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92 | solely on its inputs---for instance, it cannot refer to software or |
93 | scripts that were not explicitly passed as inputs. A build function | |
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94 | always produces the same result when passed a given set of inputs. It |
95 | cannot alter the system's environment in | |
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96 | any way; for instance, it cannot create, modify, or delete files outside |
97 | of its build and installation directories. This is achieved by running | |
e900c503 | 98 | build processes in isolated environments (or @dfn{containers}), where only their |
4bfc4ea3 | 99 | explicit inputs are visible. |
568717fd | 100 | |
e531ac2a | 101 | @cindex store |
568717fd | 102 | The result of package build functions is @dfn{cached} in the file |
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103 | system, in a special directory called @dfn{the store} (@pxref{The |
104 | Store}). Each package is installed in a directory of its own, in the | |
834129e0 | 105 | store---by default under @file{/gnu/store}. The directory name contains |
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106 | a hash of all the inputs used to build that package; thus, changing an |
107 | input yields a different directory name. | |
108 | ||
109 | This approach is the foundation of Guix's salient features: support for | |
4bfc4ea3 | 110 | transactional package upgrade and rollback, per-user installation, and |
eeaf4427 | 111 | garbage collection of packages (@pxref{Features}). |
568717fd | 112 | |
4bfc4ea3 | 113 | Guix has a command-line interface, which allows users to build, install, |
568717fd | 114 | upgrade, and remove packages, as well as a Scheme programming interface. |
568717fd | 115 | |
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116 | Last but not least, Guix is used to build a distribution of the GNU |
117 | system, with many GNU and non-GNU free software packages. @xref{GNU | |
118 | Distribution}. | |
119 | ||
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120 | @c ********************************************************************* |
121 | @node Installation | |
122 | @chapter Installation | |
123 | ||
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124 | GNU Guix is available for download from its website at |
125 | @url{http://www.gnu.org/software/guix/}. This section describes the | |
126 | software requirements of Guix, as well as how to install it and get | |
127 | ready to use it. | |
bd5e766b | 128 | |
b22a12fd | 129 | The build procedure for Guix is the same as for other GNU software, and |
1da983b9 | 130 | is not covered here. Please see the files @file{README} and |
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131 | @file{INSTALL} in the Guix source tree for additional details. |
132 | ||
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133 | @menu |
134 | * Requirements:: Software needed to build and run Guix. | |
135 | * Setting Up the Daemon:: Preparing the build daemon's environment. | |
136 | * Invoking guix-daemon:: Running the build daemon. | |
137 | @end menu | |
138 | ||
139 | @node Requirements | |
140 | @section Requirements | |
141 | ||
142 | GNU Guix depends on the following packages: | |
143 | ||
144 | @itemize | |
4a328f73 | 145 | @item @url{http://gnu.org/software/guile/, GNU Guile}, version 2.0.5 or later; |
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146 | @item @url{http://gnupg.org/, GNU libgcrypt} |
147 | @end itemize | |
148 | ||
149 | Unless @code{--disable-daemon} was passed to @command{configure}, the | |
150 | following packages are also needed: | |
151 | ||
152 | @itemize | |
153 | @item @url{http://sqlite.org, SQLite 3} | |
154 | @item @url{http://www.bzip.org, libbz2} | |
155 | @item @url{http://gcc.gnu.org, GCC's g++} | |
156 | @end itemize | |
157 | ||
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158 | When a working installation of @url{http://nixos.org/nix/, the Nix package |
159 | manager} is available, you | |
bd5e766b | 160 | can instead configure Guix with @code{--disable-daemon}. In that case, |
4bfc4ea3 | 161 | Nix replaces the three dependencies above. |
bd5e766b | 162 | |
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163 | Guix is compatible with Nix, so it is possible to share the same store |
164 | between both. To do so, you must pass @command{configure} not only the | |
165 | same @code{--with-store-dir} value, but also the same | |
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166 | @code{--localstatedir} value. The latter is essential because it |
167 | specifies where the database that stores metadata about the store is | |
834129e0 | 168 | located, among other things. The default values for Nix are |
b22a12fd | 169 | @code{--with-store-dir=/nix/store} and @code{--localstatedir=/nix/var}. |
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170 | Note that @code{--disable-daemon} is not required if |
171 | your goal is to share the store with Nix. | |
b22a12fd | 172 | |
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173 | @node Setting Up the Daemon |
174 | @section Setting Up the Daemon | |
175 | ||
176 | @cindex daemon | |
177 | Operations such as building a package or running the garbage collector | |
49e6291a | 178 | are all performed by a specialized process, the @dfn{build daemon}, on |
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179 | behalf of clients. Only the daemon may access the store and its |
180 | associated database. Thus, any operation that manipulates the store | |
181 | goes through the daemon. For instance, command-line tools such as | |
e49951eb | 182 | @command{guix package} and @command{guix build} communicate with the |
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183 | daemon (@i{via} remote procedure calls) to instruct it what to do. |
184 | ||
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185 | The following sections explain how to prepare the build daemon's |
186 | environment. | |
187 | ||
188 | @menu | |
189 | * Build Environment Setup:: Preparing the isolated build environment. | |
190 | * Daemon Offload Setup:: Offloading builds to remote machines. | |
191 | @end menu | |
192 | ||
193 | @node Build Environment Setup | |
194 | @subsection Build Environment Setup | |
195 | ||
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196 | In a standard multi-user setup, Guix and its daemon---the |
197 | @command{guix-daemon} program---are installed by the system | |
834129e0 | 198 | administrator; @file{/gnu/store} is owned by @code{root} and |
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199 | @command{guix-daemon} runs as @code{root}. Unprivileged users may use |
200 | Guix tools to build packages or otherwise access the store, and the | |
201 | daemon will do it on their behalf, ensuring that the store is kept in a | |
202 | consistent state, and allowing built packages to be shared among users. | |
203 | ||
204 | @cindex build users | |
205 | When @command{guix-daemon} runs as @code{root}, you may not want package | |
206 | build processes themselves to run as @code{root} too, for obvious | |
207 | security reasons. To avoid that, a special pool of @dfn{build users} | |
208 | should be created for use by build processes started by the daemon. | |
209 | These build users need not have a shell and a home directory: they will | |
210 | just be used when the daemon drops @code{root} privileges in build | |
211 | processes. Having several such users allows the daemon to launch | |
212 | distinct build processes under separate UIDs, which guarantees that they | |
213 | do not interfere with each other---an essential feature since builds are | |
214 | regarded as pure functions (@pxref{Introduction}). | |
215 | ||
216 | On a GNU/Linux system, a build user pool may be created like this (using | |
217 | Bash syntax and the @code{shadow} commands): | |
218 | ||
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219 | @c See http://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html |
220 | @c for why `-G' is needed. | |
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221 | @example |
222 | # groupadd guix-builder | |
223 | # for i in `seq 1 10`; | |
224 | do | |
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225 | useradd -g guix-builder -G guix-builder \ |
226 | -d /var/empty -s `which nologin` \ | |
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227 | -c "Guix build user $i" --system \ |
228 | guix-builder$i; | |
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229 | done |
230 | @end example | |
231 | ||
232 | @noindent | |
233 | The @code{guix-daemon} program may then be run as @code{root} with: | |
234 | ||
235 | @example | |
236 | # guix-daemon --build-users-group=guix-builder | |
237 | @end example | |
238 | ||
e900c503 | 239 | @cindex chroot |
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240 | @noindent |
241 | This way, the daemon starts build processes in a chroot, under one of | |
242 | the @code{guix-builder} users. On GNU/Linux, by default, the chroot | |
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243 | environment contains nothing but: |
244 | ||
245 | @c Keep this list in sync with libstore/build.cc! ----------------------- | |
246 | @itemize | |
247 | @item | |
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248 | a minimal @code{/dev} directory, created mostly independently from the |
249 | host @code{/dev}@footnote{``Mostly'', because while the set of files | |
250 | that appear in the chroot's @code{/dev} is fixed, most of these files | |
251 | can only be created if the host has them.}; | |
252 | ||
253 | @item | |
254 | the @code{/proc} directory; it only shows the container's processes | |
255 | since a separate PID name space is used; | |
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256 | |
257 | @item | |
258 | @file{/etc/passwd} with an entry for the current user and an entry for | |
259 | user @file{nobody}; | |
260 | ||
261 | @item | |
262 | @file{/etc/group} with an entry for the user's group; | |
263 | ||
264 | @item | |
265 | @file{/etc/hosts} with an entry that maps @code{localhost} to | |
266 | @code{127.0.0.1}; | |
267 | ||
268 | @item | |
269 | a writable @file{/tmp} directory. | |
270 | @end itemize | |
b095792f | 271 | |
d43eb499 | 272 | If you are installing Guix as an unprivileged user, it is still |
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273 | possible to run @command{guix-daemon}. However, build processes will |
274 | not be isolated from one another, and not from the rest of the system. | |
275 | Thus, build processes may interfere with each other, and may access | |
276 | programs, libraries, and other files available on the system---making it | |
277 | much harder to view them as @emph{pure} functions. | |
278 | ||
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279 | |
280 | @node Daemon Offload Setup | |
281 | @subsection Using the Offload Facility | |
282 | ||
283 | @cindex offloading | |
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284 | @cindex build hook |
285 | When desired, the build daemon can @dfn{offload} | |
286 | derivation builds to other machines | |
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287 | running Guix, using the @code{offload} @dfn{build hook}. When that |
288 | feature is enabled, a list of user-specified build machines is read from | |
289 | @file{/etc/guix/machines.scm}; anytime a build is requested, for | |
290 | instance via @code{guix build}, the daemon attempts to offload it to one | |
291 | of the machines that satisfies the derivation's constraints, in | |
292 | particular its system type---e.g., @file{x86_64-linux}. Missing | |
293 | prerequisites for the build are copied over SSH to the target machine, | |
294 | which then proceeds with the build; upon success the output(s) of the | |
295 | build are copied back to the initial machine. | |
296 | ||
4ec2e92d | 297 | The @file{/etc/guix/machines.scm} file typically looks like this: |
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298 | |
299 | @example | |
300 | (list (build-machine | |
301 | (name "eightysix.example.org") | |
302 | (system "x86_64-linux") | |
303 | (user "bob") | |
304 | (speed 2.)) ; incredibly fast! | |
305 | ||
306 | (build-machine | |
307 | (name "meeps.example.org") | |
308 | (system "mips64el-linux") | |
309 | (user "alice") | |
310 | (private-key | |
311 | (string-append (getenv "HOME") | |
312 | "/.ssh/id-rsa-for-guix")))) | |
313 | @end example | |
314 | ||
315 | @noindent | |
316 | In the example above we specify a list of two build machines, one for | |
317 | the @code{x86_64} architecture and one for the @code{mips64el} | |
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318 | architecture. |
319 | ||
320 | In fact, this file is---not surprisingly!---a Scheme file that is | |
321 | evaluated when the @code{offload} hook is started. Its return value | |
322 | must be a list of @code{build-machine} objects. While this example | |
323 | shows a fixed list of build machines, one could imagine, say, using | |
324 | DNS-SD to return a list of potential build machines discovered in the | |
325 | local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using | |
326 | Avahi in Guile Scheme Programs}). | |
327 | ||
328 | The compulsory fields for a @code{build-machine} declaration are: | |
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329 | |
330 | @table @code | |
331 | ||
332 | @item name | |
333 | The remote machine's host name. | |
334 | ||
335 | @item system | |
336 | The remote machine's system type. | |
337 | ||
338 | @item user | |
339 | The user account to use when connecting to the remote machine over SSH. | |
340 | Note that the SSH key pair must @emph{not} be passphrase-protected, to | |
341 | allow non-interactive logins. | |
342 | ||
343 | @end table | |
344 | ||
345 | @noindent | |
4ec2e92d | 346 | A number of optional fields may be specified: |
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347 | |
348 | @table @code | |
349 | ||
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350 | @item port |
351 | Port number of the machine's SSH server (default: 22). | |
352 | ||
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353 | @item private-key |
354 | The SSH private key file to use when connecting to the machine. | |
355 | ||
356 | @item parallel-builds | |
357 | The number of builds that may run in parallel on the machine (1 by | |
358 | default.) | |
359 | ||
360 | @item speed | |
361 | A ``relative speed factor''. The offload scheduler will tend to prefer | |
362 | machines with a higher speed factor. | |
363 | ||
364 | @item features | |
365 | A list of strings denoting specific features supported by the machine. | |
366 | An example is @code{"kvm"} for machines that have the KVM Linux modules | |
367 | and corresponding hardware support. Derivations can request features by | |
368 | name, and they will be scheduled on matching build machines. | |
369 | ||
370 | @end table | |
371 | ||
372 | The @code{guix} command must be in the search path on the build | |
373 | machines, since offloading works by invoking the @code{guix archive} and | |
374 | @code{guix build} commands. | |
375 | ||
376 | There's one last thing to do once @file{machines.scm} is in place. As | |
377 | explained above, when offloading, files are transferred back and forth | |
378 | between the machine stores. For this to work, you need to generate a | |
379 | key pair to allow the daemon to export signed archives of files from the | |
380 | store (@pxref{Invoking guix archive}): | |
381 | ||
382 | @example | |
383 | # guix archive --generate-key | |
384 | @end example | |
385 | ||
386 | @noindent | |
387 | Thus, when receiving files, a machine's build daemon can make sure they | |
388 | are genuine, have not been tampered with, and that they are signed by an | |
389 | authorized key. | |
390 | ||
391 | ||
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392 | @node Invoking guix-daemon |
393 | @section Invoking @command{guix-daemon} | |
394 | ||
395 | The @command{guix-daemon} program implements all the functionality to | |
396 | access the store. This includes launching build processes, running the | |
397 | garbage collector, querying the availability of a build result, etc. It | |
398 | is normally run as @code{root} like this: | |
399 | ||
400 | @example | |
401 | # guix-daemon --build-users-group=guix-builder | |
402 | @end example | |
403 | ||
404 | @noindent | |
405 | For details on how to set it up, @ref{Setting Up the Daemon}. | |
406 | ||
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407 | @cindex chroot |
408 | @cindex container, build environment | |
409 | @cindex build environment | |
410 | @cindex reproducible builds | |
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411 | By default, @command{guix-daemon} launches build processes under |
412 | different UIDs, taken from the build group specified with | |
413 | @code{--build-users-group}. In addition, each build process is run in a | |
414 | chroot environment that only contains the subset of the store that the | |
415 | build process depends on, as specified by its derivation | |
416 | (@pxref{Programming Interface, derivation}), plus a set of specific | |
417 | system directories. By default, the latter contains @file{/dev} and | |
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418 | @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a |
419 | @dfn{container}: in addition to having its own file system tree, it has | |
420 | a separate mount name space, its own PID name space, network name space, | |
421 | etc. This helps achieve reproducible builds (@pxref{Features}). | |
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422 | |
423 | The following command-line options are supported: | |
424 | ||
425 | @table @code | |
426 | @item --build-users-group=@var{group} | |
427 | Take users from @var{group} to run build processes (@pxref{Setting Up | |
428 | the Daemon, build users}). | |
429 | ||
6858f9d1 | 430 | @item --no-substitutes |
b5385b52 | 431 | @cindex substitutes |
6858f9d1 | 432 | Do not use substitutes for build products. That is, always build things |
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433 | locally instead of allowing downloads of pre-built binaries |
434 | (@pxref{Substitutes}). | |
6858f9d1 | 435 | |
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436 | By default substitutes are used, unless the client---such as the |
437 | @command{guix package} command---is explicitly invoked with | |
438 | @code{--no-substitutes}. | |
439 | ||
440 | When the daemon runs with @code{--no-substitutes}, clients can still | |
441 | explicitly enable substitution @i{via} the @code{set-build-options} | |
442 | remote procedure call (@pxref{The Store}). | |
443 | ||
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444 | @cindex build hook |
445 | @item --no-build-hook | |
446 | Do not use the @dfn{build hook}. | |
447 | ||
448 | The build hook is a helper program that the daemon can start and to | |
449 | which it submits build requests. This mechanism is used to offload | |
450 | builds to other machines (@pxref{Daemon Offload Setup}). | |
451 | ||
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452 | @item --cache-failures |
453 | Cache build failures. By default, only successful builds are cached. | |
454 | ||
455 | @item --cores=@var{n} | |
456 | @itemx -c @var{n} | |
457 | Use @var{n} CPU cores to build each derivation; @code{0} means as many | |
458 | as available. | |
459 | ||
460 | The default value is @code{1}, but it may be overridden by clients, such | |
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461 | as the @code{--cores} option of @command{guix build} (@pxref{Invoking |
462 | guix build}). | |
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463 | |
464 | The effect is to define the @code{NIX_BUILD_CORES} environment variable | |
465 | in the build process, which can then use it to exploit internal | |
466 | parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}. | |
467 | ||
468 | @item --max-jobs=@var{n} | |
469 | @itemx -M @var{n} | |
470 | Allow at most @var{n} build jobs in parallel. The default value is | |
471 | @code{1}. | |
472 | ||
473 | @item --debug | |
474 | Produce debugging output. | |
475 | ||
476 | This is useful to debug daemon start-up issues, but then it may be | |
477 | overridden by clients, for example the @code{--verbosity} option of | |
e49951eb | 478 | @command{guix build} (@pxref{Invoking guix build}). |
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479 | |
480 | @item --chroot-directory=@var{dir} | |
481 | Add @var{dir} to the build chroot. | |
482 | ||
483 | Doing this may change the result of build processes---for instance if | |
484 | they use optional dependencies found in @var{dir} when it is available, | |
485 | and not otherwise. For that reason, it is not recommended to do so. | |
486 | Instead, make sure that each derivation declares all the inputs that it | |
487 | needs. | |
488 | ||
489 | @item --disable-chroot | |
490 | Disable chroot builds. | |
491 | ||
492 | Using this option is not recommended since, again, it would allow build | |
493 | processes to gain access to undeclared dependencies. | |
494 | ||
495 | @item --disable-log-compression | |
496 | Disable compression of the build logs. | |
497 | ||
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498 | Unless @code{--lose-logs} is used, all the build logs are kept in the |
499 | @var{localstatedir}. To save space, the daemon automatically compresses | |
500 | them with bzip2 by default. This option disables that. | |
501 | ||
bd5e766b LC |
502 | @item --disable-store-optimization |
503 | Disable automatic file ``deduplication'' in the store. | |
504 | ||
1da983b9 LC |
505 | By default, files added to the store are automatically ``deduplicated'': |
506 | if a newly added file is identical as another one found in the store, | |
507 | the daemon makes the new file a hard link to the other file. This | |
508 | slightly increases the input/output load at the end of a build process. | |
509 | This option disables this. | |
510 | ||
6e37066e LC |
511 | @item --gc-keep-outputs[=yes|no] |
512 | Tell whether the garbage collector (GC) must keep outputs of live | |
513 | derivations. | |
514 | ||
515 | When set to ``yes'', the GC will keep the outputs of any live derivation | |
516 | available in the store---the @code{.drv} files. The default is ``no'', | |
517 | meaning that derivation outputs are kept only if they are GC roots. | |
518 | ||
519 | @item --gc-keep-derivations[=yes|no] | |
520 | Tell whether the garbage collector (GC) must keep derivations | |
521 | corresponding to live outputs. | |
522 | ||
523 | When set to ``yes'', as is the case by default, the GC keeps | |
524 | derivations---i.e., @code{.drv} files---as long as at least one of their | |
525 | outputs is live. This allows users to keep track of the origins of | |
526 | items in their store. Setting it to ``no'' saves a bit of disk space. | |
527 | ||
528 | Note that when both @code{--gc-keep-derivations} and | |
529 | @code{--gc-keep-outputs} are used, the effect is to keep all the build | |
530 | prerequisites (the sources, compiler, libraries, and other build-time | |
531 | tools) of live objects in the store, regardless of whether these | |
532 | prerequisites are live. This is convenient for developers since it | |
533 | saves rebuilds or downloads. | |
534 | ||
bd5e766b LC |
535 | @item --impersonate-linux-2.6 |
536 | On Linux-based systems, impersonate Linux 2.6. This means that the | |
537 | kernel's @code{uname} system call will report 2.6 as the release number. | |
538 | ||
539 | This might be helpful to build programs that (usually wrongfully) depend | |
540 | on the kernel version number. | |
541 | ||
542 | @item --lose-logs | |
543 | Do not keep build logs. By default they are kept under | |
544 | @code{@var{localstatedir}/nix/log}. | |
545 | ||
546 | @item --system=@var{system} | |
547 | Assume @var{system} as the current system type. By default it is the | |
548 | architecture/kernel pair found at configure time, such as | |
549 | @code{x86_64-linux}. | |
b8d2aa26 LC |
550 | |
551 | @item --listen=@var{socket} | |
552 | Listen for connections on @var{socket}, the file name of a Unix-domain | |
553 | socket. The default socket is | |
554 | @file{@var{localstatedir}/daemon-socket/socket}. This option is only | |
555 | useful in exceptional circumstances, such as if you need to run several | |
556 | daemons on the same machine. | |
bd5e766b LC |
557 | @end table |
558 | ||
559 | ||
eeaf4427 LC |
560 | @c ********************************************************************* |
561 | @node Package Management | |
562 | @chapter Package Management | |
563 | ||
f8348b91 | 564 | The purpose of GNU Guix is to allow users to easily install, upgrade, and |
eeaf4427 LC |
565 | remove software packages, without having to know about their build |
566 | procedure or dependencies. Guix also goes beyond this obvious set of | |
567 | features. | |
568 | ||
569 | This chapter describes the main features of Guix, as well as the package | |
570 | management tools it provides. | |
571 | ||
572 | @menu | |
573 | * Features:: How Guix will make your life brighter. | |
e49951eb | 574 | * Invoking guix package:: Package installation, removal, etc. |
c4202d60 | 575 | * Substitutes:: Downloading pre-built binaries. |
760c60d6 | 576 | * Packages with Multiple Outputs:: Single source package, multiple outputs. |
e49951eb | 577 | * Invoking guix gc:: Running the garbage collector. |
f651b477 | 578 | * Invoking guix pull:: Fetching the latest Guix and distribution. |
760c60d6 | 579 | * Invoking guix archive:: Exporting and importing store files. |
eeaf4427 LC |
580 | @end menu |
581 | ||
582 | @node Features | |
583 | @section Features | |
584 | ||
585 | When using Guix, each package ends up in the @dfn{package store}, in its | |
586 | own directory---something that resembles | |
834129e0 | 587 | @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string. |
eeaf4427 LC |
588 | |
589 | Instead of referring to these directories, users have their own | |
590 | @dfn{profile}, which points to the packages that they actually want to | |
821b0015 LC |
591 | use. These profiles are stored within each user's home directory, at |
592 | @code{$HOME/.guix-profile}. | |
eeaf4427 | 593 | |
821b0015 | 594 | For example, @code{alice} installs GCC 4.7.2. As a result, |
eeaf4427 | 595 | @file{/home/alice/.guix-profile/bin/gcc} points to |
834129e0 | 596 | @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine, |
821b0015 LC |
597 | @code{bob} had already installed GCC 4.8.0. The profile of @code{bob} |
598 | simply continues to point to | |
834129e0 | 599 | @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC |
821b0015 | 600 | coexist on the same system without any interference. |
eeaf4427 | 601 | |
e49951eb MW |
602 | The @command{guix package} command is the central tool to manage |
603 | packages (@pxref{Invoking guix package}). It operates on those per-user | |
821b0015 | 604 | profiles, and can be used @emph{with normal user privileges}. |
eeaf4427 LC |
605 | |
606 | The command provides the obvious install, remove, and upgrade | |
607 | operations. Each invocation is actually a @emph{transaction}: either | |
ba55b1cb | 608 | the specified operation succeeds, or nothing happens. Thus, if the |
e49951eb | 609 | @command{guix package} process is terminated during the transaction, |
eeaf4427 LC |
610 | or if a power outage occurs during the transaction, then the user's |
611 | profile remains in its previous state, and remains usable. | |
612 | ||
613 | In addition, any package transaction may be @emph{rolled back}. So, if, | |
614 | for example, an upgrade installs a new version of a package that turns | |
615 | out to have a serious bug, users may roll back to the previous instance | |
4af2447e LC |
616 | of their profile, which was known to work well. Similarly, the global |
617 | system configuration is subject to transactional upgrades and roll-back | |
618 | (@pxref{Using the Configuration System}). | |
eeaf4427 LC |
619 | |
620 | All those packages in the package store may be @emph{garbage-collected}. | |
621 | Guix can determine which packages are still referenced by the user | |
fe8ff028 | 622 | profiles, and remove those that are provably no longer referenced |
e49951eb | 623 | (@pxref{Invoking guix gc}). Users may also explicitly remove old |
fe8ff028 LC |
624 | generations of their profile so that the packages they refer to can be |
625 | collected. | |
eeaf4427 | 626 | |
e900c503 LC |
627 | @cindex reproducibility |
628 | @cindex reproducible builds | |
eeaf4427 LC |
629 | Finally, Guix takes a @dfn{purely functional} approach to package |
630 | management, as described in the introduction (@pxref{Introduction}). | |
834129e0 | 631 | Each @file{/gnu/store} package directory name contains a hash of all the |
eeaf4427 LC |
632 | inputs that were used to build that package---compiler, libraries, build |
633 | scripts, etc. This direct correspondence allows users to make sure a | |
634 | given package installation matches the current state of their | |
e900c503 LC |
635 | distribution. It also helps maximize @dfn{build reproducibility}: |
636 | thanks to the isolated build environments that are used, a given build | |
637 | is likely to yield bit-identical files when performed on different | |
638 | machines (@pxref{Invoking guix-daemon, container}). | |
eeaf4427 | 639 | |
c4202d60 | 640 | @cindex substitutes |
eeaf4427 | 641 | This foundation allows Guix to support @dfn{transparent binary/source |
c4202d60 | 642 | deployment}. When a pre-built binary for a @file{/gnu/store} item is |
18f2887b | 643 | available from an external source---a @dfn{substitute}, Guix just |
c4202d60 LC |
644 | downloads it and unpacks it; |
645 | otherwise, it builds the package from source, locally | |
646 | (@pxref{Substitutes}). | |
eeaf4427 | 647 | |
e49951eb MW |
648 | @node Invoking guix package |
649 | @section Invoking @command{guix package} | |
eeaf4427 | 650 | |
e49951eb | 651 | The @command{guix package} command is the tool that allows users to |
eeaf4427 LC |
652 | install, upgrade, and remove packages, as well as rolling back to |
653 | previous configurations. It operates only on the user's own profile, | |
654 | and works with normal user privileges (@pxref{Features}). Its syntax | |
655 | is: | |
656 | ||
657 | @example | |
e49951eb | 658 | guix package @var{options} |
eeaf4427 LC |
659 | @end example |
660 | ||
ba55b1cb | 661 | Primarily, @var{options} specifies the operations to be performed during |
eeaf4427 LC |
662 | the transaction. Upon completion, a new profile is created, but |
663 | previous generations of the profile remain available, should the user | |
664 | want to roll back. | |
665 | ||
6447738c MW |
666 | For example, to remove @code{lua} and install @code{guile} and |
667 | @code{guile-cairo} in a single transaction: | |
668 | ||
669 | @example | |
670 | guix package -r lua -i guile guile-cairo | |
671 | @end example | |
672 | ||
b9e5c0a9 | 673 | For each user, a symlink to the user's default profile is automatically |
0ec1af59 | 674 | created in @file{$HOME/.guix-profile}. This symlink always points to the |
b9e5c0a9 LC |
675 | current generation of the user's default profile. Thus, users can add |
676 | @file{$HOME/.guix-profile/bin} to their @code{PATH} environment | |
677 | variable, and so on. | |
678 | ||
0ec1af59 LC |
679 | In a multi-user setup, user profiles must be stored in a place |
680 | registered as a @dfn{garbage-collector root}, which | |
e49951eb | 681 | @file{$HOME/.guix-profile} points to (@pxref{Invoking guix gc}). That |
0ec1af59 LC |
682 | directory is normally |
683 | @code{@var{localstatedir}/profiles/per-user/@var{user}}, where | |
684 | @var{localstatedir} is the value passed to @code{configure} as | |
685 | @code{--localstatedir}, and @var{user} is the user name. It must be | |
686 | created by @code{root}, with @var{user} as the owner. When it does not | |
70c43291 LC |
687 | exist, or is not owned by @var{user}, @command{guix package} emits an |
688 | error about it. | |
0ec1af59 LC |
689 | |
690 | The @var{options} can be among the following: | |
691 | ||
eeaf4427 LC |
692 | @table @code |
693 | ||
6447738c MW |
694 | @item --install=@var{package} @dots{} |
695 | @itemx -i @var{package} @dots{} | |
696 | Install the specified @var{package}s. | |
eeaf4427 | 697 | |
6447738c | 698 | Each @var{package} may specify either a simple package name, such as |
eeaf4427 | 699 | @code{guile}, or a package name followed by a hyphen and version number, |
dc5669cd MW |
700 | such as @code{guile-1.8.8}. If no version number is specified, the |
701 | newest available version will be selected. In addition, @var{package} | |
702 | may contain a colon, followed by the name of one of the outputs of the | |
6e721c4d | 703 | package, as in @code{gcc:doc} or @code{binutils-2.22:lib} |
e7f34eb0 LC |
704 | (@pxref{Packages with Multiple Outputs}). Packages with a corresponding |
705 | name (and optionally version) are searched for among the GNU | |
706 | distribution modules (@pxref{Package Modules}). | |
eeaf4427 | 707 | |
461572cc LC |
708 | @cindex propagated inputs |
709 | Sometimes packages have @dfn{propagated inputs}: these are dependencies | |
710 | that automatically get installed along with the required package. | |
711 | ||
712 | An example is the GNU MPC library: its C header files refer to those of | |
713 | the GNU MPFR library, which in turn refer to those of the GMP library. | |
714 | Thus, when installing MPC, the MPFR and GMP libraries also get installed | |
715 | in the profile; removing MPC also removes MPFR and GMP---unless they had | |
716 | also been explicitly installed independently. | |
717 | ||
ba7ea5ce | 718 | Besides, packages sometimes rely on the definition of environment |
5924080d | 719 | variables for their search paths (see explanation of |
ba7ea5ce | 720 | @code{--search-paths} below). Any missing or possibly incorrect |
5924080d LC |
721 | environment variable definitions are reported here. |
722 | ||
ef010c0f | 723 | @c XXX: keep me up-to-date |
5924080d | 724 | Finally, when installing a GNU package, the tool reports the |
ef010c0f LC |
725 | availability of a newer upstream version. In the future, it may provide |
726 | the option of installing directly from the upstream version, even if | |
727 | that version is not yet in the distribution. | |
728 | ||
5d4b411f LC |
729 | @item --install-from-expression=@var{exp} |
730 | @itemx -e @var{exp} | |
731 | Install the package @var{exp} evaluates to. | |
732 | ||
733 | @var{exp} must be a Scheme expression that evaluates to a | |
734 | @code{<package>} object. This option is notably useful to disambiguate | |
735 | between same-named variants of a package, with expressions such as | |
736 | @code{(@@ (gnu packages base) guile-final)}. | |
737 | ||
738 | Note that this option installs the first output of the specified | |
739 | package, which may be insufficient when needing a specific output of a | |
740 | multiple-output package. | |
741 | ||
6447738c MW |
742 | @item --remove=@var{package} @dots{} |
743 | @itemx -r @var{package} @dots{} | |
744 | Remove the specified @var{package}s. | |
eeaf4427 | 745 | |
6447738c | 746 | As for @code{--install}, each @var{package} may specify a version number |
13ed095c LC |
747 | and/or output name in addition to the package name. For instance, |
748 | @code{-r glibc:debug} would remove the @code{debug} output of | |
749 | @code{glibc}. | |
750 | ||
6447738c MW |
751 | @item --upgrade[=@var{regexp} @dots{}] |
752 | @itemx -u [@var{regexp} @dots{}] | |
753 | Upgrade all the installed packages. If one or more @var{regexp}s are | |
754 | specified, upgrade only installed packages whose name matches a | |
755 | @var{regexp}. | |
eeaf4427 | 756 | |
f651b477 LC |
757 | Note that this upgrades package to the latest version of packages found |
758 | in the distribution currently installed. To update your distribution, | |
759 | you should regularly run @command{guix pull} (@pxref{Invoking guix | |
760 | pull}). | |
761 | ||
24e262f0 LC |
762 | @item --roll-back |
763 | Roll back to the previous @dfn{generation} of the profile---i.e., undo | |
764 | the last transaction. | |
765 | ||
766 | When combined with options such as @code{--install}, roll back occurs | |
767 | before any other actions. | |
768 | ||
d9307267 | 769 | When rolling back from the first generation that actually contains |
4b2bc804 NK |
770 | installed packages, the profile is made to point to the @dfn{zeroth |
771 | generation}, which contains no files apart from its own meta-data. | |
d9307267 | 772 | |
82fe08ed LC |
773 | Installing, removing, or upgrading packages from a generation that has |
774 | been rolled back to overwrites previous future generations. Thus, the | |
775 | history of a profile's generations is always linear. | |
776 | ||
5924080d LC |
777 | @item --search-paths |
778 | @cindex search paths | |
779 | Report environment variable definitions, in Bash syntax, that may be | |
780 | needed in order to use the set of installed packages. These environment | |
781 | variables are used to specify @dfn{search paths} for files used by some | |
782 | of the installed packages. | |
783 | ||
784 | For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH} | |
785 | environment variables to be defined so it can look for headers and | |
786 | libraries in the user's profile (@pxref{Environment Variables,,, gcc, | |
787 | Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C | |
788 | library are installed in the profile, then @code{--search-paths} will | |
789 | suggest setting these variables to @code{@var{profile}/include} and | |
790 | @code{@var{profile}/lib}, respectively. | |
791 | ||
eeaf4427 LC |
792 | @item --profile=@var{profile} |
793 | @itemx -p @var{profile} | |
794 | Use @var{profile} instead of the user's default profile. | |
795 | ||
70915c1a LC |
796 | @item --verbose |
797 | Produce verbose output. In particular, emit the environment's build log | |
798 | on the standard error port. | |
799 | ||
eeaf4427 LC |
800 | @item --bootstrap |
801 | Use the bootstrap Guile to build the profile. This option is only | |
802 | useful to distribution developers. | |
803 | ||
804 | @end table | |
805 | ||
e49951eb | 806 | In addition to these actions @command{guix package} supports the |
733b4130 LC |
807 | following options to query the current state of a profile, or the |
808 | availability of packages: | |
eeaf4427 | 809 | |
733b4130 LC |
810 | @table @option |
811 | ||
acc08466 NK |
812 | @item --search=@var{regexp} |
813 | @itemx -s @var{regexp} | |
814 | List the available packages whose synopsis or description matches | |
299112d3 LC |
815 | @var{regexp}. Print all the meta-data of matching packages in |
816 | @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, | |
817 | GNU recutils manual}). | |
acc08466 | 818 | |
299112d3 LC |
819 | This allows specific fields to be extracted using the @command{recsel} |
820 | command, for instance: | |
821 | ||
822 | @example | |
e49951eb | 823 | $ guix package -s malloc | recsel -p name,version |
299112d3 LC |
824 | name: glibc |
825 | version: 2.17 | |
826 | ||
827 | name: libgc | |
828 | version: 7.2alpha6 | |
829 | @end example | |
acc08466 | 830 | |
733b4130 LC |
831 | @item --list-installed[=@var{regexp}] |
832 | @itemx -I [@var{regexp}] | |
bd9bde1c LC |
833 | List the currently installed packages in the specified profile, with the |
834 | most recently installed packages shown last. When @var{regexp} is | |
835 | specified, list only installed packages whose name matches @var{regexp}. | |
733b4130 LC |
836 | |
837 | For each installed package, print the following items, separated by | |
838 | tabs: the package name, its version string, the part of the package that | |
839 | is installed (for instance, @code{out} for the default output, | |
840 | @code{include} for its headers, etc.), and the path of this package in | |
841 | the store. | |
842 | ||
64fc89b6 LC |
843 | @item --list-available[=@var{regexp}] |
844 | @itemx -A [@var{regexp}] | |
a1ba8475 LC |
845 | List packages currently available in the software distribution |
846 | (@pxref{GNU Distribution}). When @var{regexp} is specified, list only | |
847 | installed packages whose name matches @var{regexp}. | |
64fc89b6 LC |
848 | |
849 | For each package, print the following items separated by tabs: its name, | |
6e721c4d LC |
850 | its version string, the parts of the package (@pxref{Packages with |
851 | Multiple Outputs}), and the source location of its definition. | |
64fc89b6 | 852 | |
f566d765 LC |
853 | @item --list-generations[=@var{pattern}] |
854 | @itemx -l [@var{pattern}] | |
855 | Return a list of generations along with their creation dates; for each | |
856 | generation, show the installed packages, with the most recently | |
4b2bc804 NK |
857 | installed packages shown last. Note that the zeroth generation is never |
858 | shown. | |
f566d765 LC |
859 | |
860 | For each installed package, print the following items, separated by | |
861 | tabs: the name of a package, its version string, the part of the package | |
862 | that is installed (@pxref{Packages with Multiple Outputs}), and the | |
863 | location of this package in the store. | |
864 | ||
865 | When @var{pattern} is used, the command returns only matching | |
866 | generations. Valid patterns include: | |
867 | ||
868 | @itemize | |
869 | @item @emph{Integers and comma-separated integers}. Both patterns denote | |
870 | generation numbers. For instance, @code{--list-generations=1} returns | |
871 | the first one. | |
872 | ||
873 | And @code{--list-generations=1,8,2} outputs three generations in the | |
874 | specified order. Neither spaces nor trailing commas are allowed. | |
875 | ||
876 | @item @emph{Ranges}. @code{--list-generations=2..9} prints the | |
877 | specified generations and everything in between. Note that the start of | |
878 | a range must be lesser than its end. | |
879 | ||
880 | It is also possible to omit the endpoint. For example, | |
881 | @code{--list-generations=2..}, returns all generations starting from the | |
882 | second one. | |
883 | ||
884 | @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks, | |
885 | or months by passing an integer along with the first letter of the | |
d7ddb257 LC |
886 | duration. For example, @code{--list-generations=20d} lists generations |
887 | that are up to 20 days old. | |
f566d765 LC |
888 | @end itemize |
889 | ||
b7884ca3 NK |
890 | @item --delete-generations[=@var{pattern}] |
891 | @itemx -d [@var{pattern}] | |
d7ddb257 LC |
892 | When @var{pattern} is omitted, delete all generations except the current |
893 | one. | |
b7884ca3 NK |
894 | |
895 | This command accepts the same patterns as @option{--list-generations}. | |
d7ddb257 LC |
896 | When @var{pattern} is specified, delete the matching generations. When |
897 | @var{pattern} specifies a duration, generations @emph{older} than the | |
898 | specified duration match. For instance, @code{--delete-generations=1m} | |
899 | deletes generations that are more than one month old. | |
900 | ||
901 | If the current generation matches, it is deleted atomically---i.e., by | |
902 | switching to the previous available generation. Note that the zeroth | |
903 | generation is never deleted. | |
b7884ca3 | 904 | |
1bb9900a LC |
905 | Note that deleting generations prevents roll-back to them. |
906 | Consequently, this command must be used with care. | |
907 | ||
733b4130 | 908 | @end table |
eeaf4427 | 909 | |
70ee5642 LC |
910 | Finally, since @command{guix package} may actually start build |
911 | processes, it supports all the common build options that @command{guix | |
912 | build} supports (@pxref{Invoking guix build, common build options}). | |
913 | ||
c4202d60 LC |
914 | @node Substitutes |
915 | @section Substitutes | |
916 | ||
917 | @cindex substitutes | |
918 | @cindex pre-built binaries | |
919 | Guix supports transparent source/binary deployment, which means that it | |
920 | can either build things locally, or download pre-built items from a | |
921 | server. We call these pre-built items @dfn{substitutes}---they are | |
922 | substitutes for local build results. In many cases, downloading a | |
923 | substitute is much faster than building things locally. | |
924 | ||
925 | Substitutes can be anything resulting from a derivation build | |
926 | (@pxref{Derivations}). Of course, in the common case, they are | |
927 | pre-built package binaries, but source tarballs, for instance, which | |
928 | also result from derivation builds, can be available as substitutes. | |
929 | ||
930 | The @code{hydra.gnu.org} server is a front-end to a build farm that | |
931 | builds packages from the GNU distribution continuously for some | |
932 | architectures, and makes them available as substitutes. | |
933 | ||
934 | @cindex security | |
935 | @cindex digital signatures | |
936 | To allow Guix to download substitutes from @code{hydra.gnu.org}, you | |
937 | must add its public key to the access control list (ACL) of archive | |
938 | imports, using the @command{guix archive} command (@pxref{Invoking guix | |
939 | archive}). Doing so implies that you trust @code{hydra.gnu.org} to not | |
940 | be compromised and to serve genuine substitutes. | |
941 | ||
942 | This public key is installed along with Guix, in | |
943 | @code{@var{prefix}/share/guix/hydra.gnu.org.pub}, where @var{prefix} is | |
944 | the installation prefix of Guix. If you installed Guix from source, | |
945 | make sure you checked the GPG signature of | |
946 | @file{guix-@value{VERSION}.tar.gz}, which contains this public key file. | |
947 | Then, you can run something like this: | |
948 | ||
949 | @example | |
950 | # guix archive --authorize < hydra.gnu.org.pub | |
951 | @end example | |
952 | ||
953 | Once this is in place, the output of a command like @code{guix build} | |
954 | should change from something like: | |
955 | ||
956 | @example | |
957 | $ guix build emacs --dry-run | |
958 | The following derivations would be built: | |
959 | /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv | |
960 | /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv | |
961 | /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv | |
962 | /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv | |
963 | @dots{} | |
964 | @end example | |
965 | ||
966 | @noindent | |
967 | to something like: | |
968 | ||
969 | @example | |
970 | $ guix build emacs --dry-run | |
971 | The following files would be downloaded: | |
972 | /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3 | |
973 | /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d | |
974 | /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16 | |
975 | /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7 | |
976 | @dots{} | |
977 | @end example | |
978 | ||
979 | @noindent | |
980 | This indicates that substitutes from @code{hydra.gnu.org} are usable and | |
981 | will be downloaded, when possible, for future builds. | |
982 | ||
983 | Guix ignores substitutes that are not signed, or that are not signed by | |
ef27aa9c | 984 | one of the keys listed in the ACL. It also detects and raises an error |
c4202d60 LC |
985 | when attempting to use a substitute that has been tampered with. |
986 | ||
987 | The substitute mechanism can be disabled globally by running | |
988 | @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking | |
989 | guix-daemon}). It can also be disabled temporarily by passing the | |
990 | @code{--no-substitutes} option to @command{guix package}, @command{guix | |
991 | build}, and other command-line tools. | |
992 | ||
993 | ||
994 | Today, each individual's control over their own computing is at the | |
995 | mercy of institutions, corporations, and groups with enough power and | |
996 | determination to subvert the computing infrastructure and exploit its | |
997 | weaknesses. While using @code{hydra.gnu.org} substitutes can be | |
998 | convenient, we encourage users to also build on their own, or even run | |
999 | their own build farm, such that @code{hydra.gnu.org} is less of an | |
1000 | interesting target. | |
1001 | ||
1002 | Guix has the foundations to maximize build reproducibility | |
1003 | (@pxref{Features}). In most cases, independent builds of a given | |
1004 | package or derivation should yield bit-identical results. Thus, through | |
1005 | a diverse set of independent package builds, we can strengthen the | |
1006 | integrity of our systems. | |
1007 | ||
1008 | In the future, we want Guix to have support to publish and retrieve | |
1009 | binaries to/from other users, in a peer-to-peer fashion. If you would | |
1010 | like to discuss this project, join us on @email{guix-devel@@gnu.org}. | |
1011 | ||
1012 | ||
6e721c4d LC |
1013 | @node Packages with Multiple Outputs |
1014 | @section Packages with Multiple Outputs | |
1015 | ||
1016 | @cindex multiple-output packages | |
1017 | @cindex package outputs | |
1018 | ||
1019 | Often, packages defined in Guix have a single @dfn{output}---i.e., the | |
1020 | source package leads exactly one directory in the store. When running | |
1021 | @command{guix package -i glibc}, one installs the default output of the | |
1022 | GNU libc package; the default output is called @code{out}, but its name | |
1023 | can be omitted as shown in this command. In this particular case, the | |
1024 | default output of @code{glibc} contains all the C header files, shared | |
1025 | libraries, static libraries, Info documentation, and other supporting | |
1026 | files. | |
1027 | ||
1028 | Sometimes it is more appropriate to separate the various types of files | |
1029 | produced from a single source package into separate outputs. For | |
1030 | instance, the GLib C library (used by GTK+ and related packages) | |
1031 | installs more than 20 MiB of reference documentation as HTML pages. | |
1032 | To save space for users who do not need it, the documentation goes to a | |
1033 | separate output, called @code{doc}. To install the main GLib output, | |
1034 | which contains everything but the documentation, one would run: | |
1035 | ||
1036 | @example | |
1037 | guix package -i glib | |
1038 | @end example | |
1039 | ||
1040 | The command to install its documentation is: | |
1041 | ||
1042 | @example | |
1043 | guix package -i glib:doc | |
1044 | @end example | |
1045 | ||
1046 | Some packages install programs with different ``dependency footprints''. | |
1047 | For instance, the WordNet package install both command-line tools and | |
1048 | graphical user interfaces (GUIs). The former depend solely on the C | |
1049 | library, whereas the latter depend on Tcl/Tk and the underlying X | |
1050 | libraries. In this case, we leave the command-line tools in the default | |
1051 | output, whereas the GUIs are in a separate output. This allows users | |
1052 | who do not need the GUIs to save space. | |
1053 | ||
1054 | There are several such multiple-output packages in the GNU distribution. | |
91ef73d4 LC |
1055 | Other conventional output names include @code{lib} for libraries and |
1056 | possibly header files, @code{bin} for stand-alone programs, and | |
1057 | @code{debug} for debugging information (@pxref{Installing Debugging | |
1058 | Files}). The outputs of a packages are listed in the third column of | |
1059 | the output of @command{guix package --list-available} (@pxref{Invoking | |
1060 | guix package}). | |
6e721c4d | 1061 | |
eeaf4427 | 1062 | |
e49951eb MW |
1063 | @node Invoking guix gc |
1064 | @section Invoking @command{guix gc} | |
fe8ff028 LC |
1065 | |
1066 | @cindex garbage collector | |
1067 | Packages that are installed but not used may be @dfn{garbage-collected}. | |
e49951eb | 1068 | The @command{guix gc} command allows users to explicitly run the garbage |
834129e0 | 1069 | collector to reclaim space from the @file{/gnu/store} directory. |
fe8ff028 LC |
1070 | |
1071 | The garbage collector has a set of known @dfn{roots}: any file under | |
834129e0 | 1072 | @file{/gnu/store} reachable from a root is considered @dfn{live} and |
fe8ff028 LC |
1073 | cannot be deleted; any other file is considered @dfn{dead} and may be |
1074 | deleted. The set of garbage collector roots includes default user | |
e49951eb MW |
1075 | profiles, and may be augmented with @command{guix build --root}, for |
1076 | example (@pxref{Invoking guix build}). | |
fe8ff028 | 1077 | |
1bb9900a LC |
1078 | Prior to running @code{guix gc --collect-garbage} to make space, it is |
1079 | often useful to remove old generations from user profiles; that way, old | |
1080 | package builds referenced by those generations can be reclaimed. This | |
1081 | is achieved by running @code{guix package --delete-generations} | |
1082 | (@pxref{Invoking guix package}). | |
1083 | ||
e49951eb | 1084 | The @command{guix gc} command has three modes of operation: it can be |
fe8ff028 LC |
1085 | used to garbage-collect any dead files (the default), to delete specific |
1086 | files (the @code{--delete} option), or to print garbage-collector | |
1087 | information. The available options are listed below: | |
1088 | ||
1089 | @table @code | |
1090 | @item --collect-garbage[=@var{min}] | |
1091 | @itemx -C [@var{min}] | |
834129e0 | 1092 | Collect garbage---i.e., unreachable @file{/gnu/store} files and |
fe8ff028 LC |
1093 | sub-directories. This is the default operation when no option is |
1094 | specified. | |
1095 | ||
1096 | When @var{min} is given, stop once @var{min} bytes have been collected. | |
1097 | @var{min} may be a number of bytes, or it may include a unit as a | |
1098 | suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes. | |
1099 | ||
1100 | When @var{min} is omitted, collect all the garbage. | |
1101 | ||
1102 | @item --delete | |
1103 | @itemx -d | |
1104 | Attempt to delete all the store files and directories specified as | |
1105 | arguments. This fails if some of the files are not in the store, or if | |
1106 | they are still live. | |
1107 | ||
1108 | @item --list-dead | |
1109 | Show the list of dead files and directories still present in the | |
1110 | store---i.e., files and directories no longer reachable from any root. | |
1111 | ||
1112 | @item --list-live | |
1113 | Show the list of live store files and directories. | |
ba8b732d LC |
1114 | |
1115 | @end table | |
1116 | ||
1117 | In addition, the references among existing store files can be queried: | |
1118 | ||
1119 | @table @code | |
1120 | ||
1121 | @item --references | |
1122 | @itemx --referrers | |
1123 | List the references (respectively, the referrers) of store files given | |
1124 | as arguments. | |
1125 | ||
8e59fdd5 LC |
1126 | @item --requisites |
1127 | @itemx -R | |
1128 | List the requisites of the store files passed as arguments. Requisites | |
1129 | include the store files themselves, their references, and the references | |
1130 | of these, recursively. In other words, the returned list is the | |
1131 | @dfn{transitive closure} of the store files. | |
1132 | ||
fe8ff028 LC |
1133 | @end table |
1134 | ||
eeaf4427 | 1135 | |
f651b477 LC |
1136 | @node Invoking guix pull |
1137 | @section Invoking @command{guix pull} | |
1138 | ||
1139 | Packages are installed or upgraded to the latest version available in | |
1140 | the distribution currently available on your local machine. To update | |
1141 | that distribution, along with the Guix tools, you must run @command{guix | |
1142 | pull}: the command downloads the latest Guix source code and package | |
1143 | descriptions, and deploys it. | |
1144 | ||
1145 | On completion, @command{guix package} will use packages and package | |
1146 | versions from this just-retrieved copy of Guix. Not only that, but all | |
1147 | the Guix commands and Scheme modules will also be taken from that latest | |
1148 | version. New @command{guix} sub-commands added by the update also | |
1149 | become available. | |
1150 | ||
1151 | The @command{guix pull} command is usually invoked with no arguments, | |
1152 | but it supports the following options: | |
1153 | ||
1154 | @table @code | |
1155 | @item --verbose | |
1156 | Produce verbose output, writing build logs to the standard error output. | |
1157 | ||
ab5d72ad LC |
1158 | @item --url=@var{url} |
1159 | Download the source tarball of Guix from @var{url}. | |
1160 | ||
1161 | By default, the tarball is taken from its canonical address at | |
1162 | @code{gnu.org}, for the stable branch of Guix. | |
1163 | ||
f651b477 LC |
1164 | @item --bootstrap |
1165 | Use the bootstrap Guile to build the latest Guix. This option is only | |
1166 | useful to Guix developers. | |
1167 | @end table | |
1168 | ||
760c60d6 LC |
1169 | |
1170 | @node Invoking guix archive | |
1171 | @section Invoking @command{guix archive} | |
1172 | ||
1173 | The @command{guix archive} command allows users to @dfn{export} files | |
1174 | from the store into a single archive, and to later @dfn{import} them. | |
1175 | In particular, it allows store files to be transferred from one machine | |
1176 | to another machine's store. For example, to transfer the @code{emacs} | |
1177 | package to a machine connected over SSH, one would run: | |
1178 | ||
1179 | @example | |
1180 | guix archive --export emacs | ssh the-machine guix archive --import | |
1181 | @end example | |
1182 | ||
87236aed LC |
1183 | @noindent |
1184 | However, note that, in this example, all of @code{emacs} and its | |
1185 | dependencies are transferred, regardless of what is already available in | |
1186 | the target machine's store. The @code{--missing} option can help figure | |
1187 | out which items are missing from the target's store. | |
1188 | ||
760c60d6 | 1189 | Archives are stored in the ``Nix archive'' or ``Nar'' format, which is |
0dbd88db LC |
1190 | comparable in spirit to `tar', but with a few noteworthy differences |
1191 | that make it more appropriate for our purposes. First, rather than | |
1192 | recording all Unix meta-data for each file, the Nar format only mentions | |
1193 | the file type (regular, directory, or symbolic link); Unix permissions | |
1194 | and owner/group are dismissed. Second, the order in which directory | |
1195 | entries are stored always follows the order of file names according to | |
1196 | the C locale collation order. This makes archive production fully | |
1197 | deterministic. | |
1198 | ||
1199 | When exporting, the daemon digitally signs the contents of the archive, | |
1200 | and that digital signature is appended. When importing, the daemon | |
1201 | verifies the signature and rejects the import in case of an invalid | |
1202 | signature or if the signing key is not authorized. | |
760c60d6 LC |
1203 | @c FIXME: Add xref to daemon doc about signatures. |
1204 | ||
1205 | The main options are: | |
1206 | ||
1207 | @table @code | |
1208 | @item --export | |
1209 | Export the specified store files or packages (see below.) Write the | |
1210 | resulting archive to the standard output. | |
1211 | ||
1212 | @item --import | |
1213 | Read an archive from the standard input, and import the files listed | |
1214 | therein into the store. Abort if the archive has an invalid digital | |
f82cc5fd LC |
1215 | signature, or if it is signed by a public key not among the authorized |
1216 | keys (see @code{--authorize} below.) | |
554f26ec | 1217 | |
87236aed LC |
1218 | @item --missing |
1219 | Read a list of store file names from the standard input, one per line, | |
1220 | and write on the standard output the subset of these files missing from | |
1221 | the store. | |
1222 | ||
554f26ec | 1223 | @item --generate-key[=@var{parameters}] |
f82cc5fd | 1224 | @cindex signing, archives |
554f26ec LC |
1225 | Generate a new key pair for the daemons. This is a prerequisite before |
1226 | archives can be exported with @code{--export}. Note that this operation | |
1227 | usually takes time, because it needs to gather enough entropy to | |
1228 | generate the key pair. | |
1229 | ||
1230 | The generated key pair is typically stored under @file{/etc/guix}, in | |
1231 | @file{signing-key.pub} (public key) and @file{signing-key.sec} (private | |
1232 | key, which must be kept secret.) When @var{parameters} is omitted, it | |
1233 | is a 4096-bit RSA key. Alternately, @var{parameters} can specify | |
1234 | @code{genkey} parameters suitable for Libgcrypt (@pxref{General | |
1235 | public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The | |
1236 | Libgcrypt Reference Manual}). | |
f82cc5fd LC |
1237 | |
1238 | @item --authorize | |
1239 | @cindex authorizing, archives | |
1240 | Authorize imports signed by the public key passed on standard input. | |
1241 | The public key must be in ``s-expression advanced format''---i.e., the | |
1242 | same format as the @file{signing-key.pub} file. | |
1243 | ||
1244 | The list of authorized keys is kept in the human-editable file | |
1245 | @file{/etc/guix/acl}. The file contains | |
1246 | @url{http://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format | |
1247 | s-expressions''} and is structured as an access-control list in the | |
1248 | @url{http://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure | |
1249 | (SPKI)}. | |
760c60d6 LC |
1250 | @end table |
1251 | ||
1252 | To export store files as an archive to the standard output, run: | |
1253 | ||
1254 | @example | |
1255 | guix archive --export @var{options} @var{specifications}... | |
1256 | @end example | |
1257 | ||
1258 | @var{specifications} may be either store file names or package | |
1259 | specifications, as for @command{guix package} (@pxref{Invoking guix | |
1260 | package}). For instance, the following command creates an archive | |
1261 | containing the @code{gui} output of the @code{git} package and the main | |
1262 | output of @code{emacs}: | |
1263 | ||
1264 | @example | |
834129e0 | 1265 | guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar |
760c60d6 LC |
1266 | @end example |
1267 | ||
1268 | If the specified packages are not built yet, @command{guix archive} | |
1269 | automatically builds them. The build process may be controlled with the | |
1270 | same options that can be passed to the @command{guix build} command | |
70ee5642 | 1271 | (@pxref{Invoking guix build, common build options}). |
760c60d6 LC |
1272 | |
1273 | ||
568717fd LC |
1274 | @c ********************************************************************* |
1275 | @node Programming Interface | |
1276 | @chapter Programming Interface | |
1277 | ||
3dc1970d LC |
1278 | GNU Guix provides several Scheme programming interfaces (APIs) to |
1279 | define, build, and query packages. The first interface allows users to | |
1280 | write high-level package definitions. These definitions refer to | |
1281 | familiar packaging concepts, such as the name and version of a package, | |
1282 | its build system, and its dependencies. These definitions can then be | |
1283 | turned into concrete build actions. | |
1284 | ||
ba55b1cb | 1285 | Build actions are performed by the Guix daemon, on behalf of users. In a |
3dc1970d | 1286 | standard setup, the daemon has write access to the store---the |
834129e0 | 1287 | @file{/gnu/store} directory---whereas users do not. The recommended |
3dc1970d LC |
1288 | setup also has the daemon perform builds in chroots, under a specific |
1289 | build users, to minimize interference with the rest of the system. | |
1290 | ||
1291 | @cindex derivation | |
1292 | Lower-level APIs are available to interact with the daemon and the | |
1293 | store. To instruct the daemon to perform a build action, users actually | |
1294 | provide it with a @dfn{derivation}. A derivation is a low-level | |
1295 | representation of the build actions to be taken, and the environment in | |
1296 | which they should occur---derivations are to package definitions what | |
1297 | assembly is to C programs. | |
1298 | ||
1299 | This chapter describes all these APIs in turn, starting from high-level | |
1300 | package definitions. | |
1301 | ||
568717fd | 1302 | @menu |
b860f382 | 1303 | * Defining Packages:: Defining new packages. |
7458bd0a | 1304 | * Build Systems:: Specifying how packages are built. |
b860f382 LC |
1305 | * The Store:: Manipulating the package store. |
1306 | * Derivations:: Low-level interface to package derivations. | |
1307 | * The Store Monad:: Purely functional interface to the store. | |
21b679f6 | 1308 | * G-Expressions:: Manipulating build expressions. |
568717fd LC |
1309 | @end menu |
1310 | ||
1311 | @node Defining Packages | |
1312 | @section Defining Packages | |
1313 | ||
3dc1970d LC |
1314 | The high-level interface to package definitions is implemented in the |
1315 | @code{(guix packages)} and @code{(guix build-system)} modules. As an | |
1316 | example, the package definition, or @dfn{recipe}, for the GNU Hello | |
1317 | package looks like this: | |
1318 | ||
1319 | @example | |
e7f34eb0 LC |
1320 | (define-module (gnu packages hello) |
1321 | #:use-module (guix packages) | |
1322 | #:use-module (guix download) | |
1323 | #:use-module (guix build-system gnu) | |
1324 | #:use-module (guix licenses)) | |
b22a12fd | 1325 | |
3dc1970d LC |
1326 | (define hello |
1327 | (package | |
1328 | (name "hello") | |
1329 | (version "2.8") | |
1330 | (source (origin | |
1331 | (method url-fetch) | |
1332 | (uri (string-append "mirror://gnu/hello/hello-" version | |
1333 | ".tar.gz")) | |
1334 | (sha256 | |
1335 | (base32 "0wqd8sjmxfskrflaxywc7gqw7sfawrfvdxd9skxawzfgyy0pzdz6")))) | |
1336 | (build-system gnu-build-system) | |
7458bd0a | 1337 | (arguments `(#:configure-flags '("--enable-silent-rules"))) |
3dc1970d | 1338 | (inputs `(("gawk" ,gawk))) |
7458bd0a LC |
1339 | (synopsis "Hello, GNU world: An example GNU package") |
1340 | (description "Guess what GNU Hello prints!") | |
3dc1970d | 1341 | (home-page "http://www.gnu.org/software/hello/") |
b22a12fd | 1342 | (license gpl3+))) |
3dc1970d LC |
1343 | @end example |
1344 | ||
1345 | @noindent | |
1346 | Without being a Scheme expert, the reader may have guessed the meaning | |
e7f34eb0 | 1347 | of the various fields here. This expression binds variable @code{hello} |
3dc1970d LC |
1348 | to a @code{<package>} object, which is essentially a record |
1349 | (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}). | |
1350 | This package object can be inspected using procedures found in the | |
1351 | @code{(guix packages)} module; for instance, @code{(package-name hello)} | |
1352 | returns---surprise!---@code{"hello"}. | |
1353 | ||
e7f34eb0 LC |
1354 | In the example above, @var{hello} is defined into a module of its own, |
1355 | @code{(gnu packages hello)}. Technically, this is not strictly | |
1356 | necessary, but it is convenient to do so: all the packages defined in | |
1357 | modules under @code{(gnu packages @dots{})} are automatically known to | |
1358 | the command-line tools (@pxref{Package Modules}). | |
1359 | ||
3dc1970d LC |
1360 | There are a few points worth noting in the above package definition: |
1361 | ||
1362 | @itemize | |
1363 | @item | |
1364 | The @code{source} field of the package is an @code{<origin>} object. | |
1365 | Here, the @code{url-fetch} method from @code{(guix download)} is used, | |
1366 | meaning that the source is a file to be downloaded over FTP or HTTP. | |
1367 | ||
1368 | The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of | |
1369 | the GNU mirrors defined in @code{(guix download)}. | |
1370 | ||
1371 | The @code{sha256} field specifies the expected SHA256 hash of the file | |
1372 | being downloaded. It is mandatory, and allows Guix to check the | |
1373 | integrity of the file. The @code{(base32 @dots{})} form introduces the | |
6c365eca | 1374 | base32 representation of the hash. You can obtain this information with |
210cc920 LC |
1375 | @code{guix download} (@pxref{Invoking guix download}) and @code{guix |
1376 | hash} (@pxref{Invoking guix hash}). | |
3dc1970d | 1377 | |
f9cc8971 LC |
1378 | @cindex patches |
1379 | When needed, the @code{origin} form can also have a @code{patches} field | |
1380 | listing patches to be applied, and a @code{snippet} field giving a | |
1381 | Scheme expression to modify the source code. | |
1382 | ||
3dc1970d LC |
1383 | @item |
1384 | @cindex GNU Build System | |
7458bd0a LC |
1385 | The @code{build-system} field specifies the procedure to build the |
1386 | package (@pxref{Build Systems}). Here, @var{gnu-build-system} | |
1387 | represents the familiar GNU Build System, where packages may be | |
1388 | configured, built, and installed with the usual @code{./configure && | |
1389 | make && make check && make install} command sequence. | |
1390 | ||
1391 | @item | |
1392 | The @code{arguments} field specifies options for the build system | |
1393 | (@pxref{Build Systems}). Here it is interpreted by | |
1394 | @var{gnu-build-system} as a request run @file{configure} with the | |
1395 | @code{--enable-silent-rules} flag. | |
3dc1970d LC |
1396 | |
1397 | @item | |
1398 | The @code{inputs} field specifies inputs to the build process---i.e., | |
1399 | build-time or run-time dependencies of the package. Here, we define an | |
1400 | input called @code{"gawk"} whose value is that of the @var{gawk} | |
1401 | variable; @var{gawk} is itself bound to a @code{<package>} object. | |
1402 | ||
1403 | Note that GCC, Coreutils, Bash, and other essential tools do not need to | |
1404 | be specified as inputs here. Instead, @var{gnu-build-system} takes care | |
7458bd0a | 1405 | of ensuring that they are present (@pxref{Build Systems}). |
3dc1970d LC |
1406 | |
1407 | However, any other dependencies need to be specified in the | |
1408 | @code{inputs} field. Any dependency not specified here will simply be | |
1409 | unavailable to the build process, possibly leading to a build failure. | |
1410 | @end itemize | |
1411 | ||
3dc1970d LC |
1412 | Once a package definition is in place@footnote{Simple package |
1413 | definitions like the one above may be automatically converted from the | |
e49951eb MW |
1414 | Nixpkgs distribution using the @command{guix import} command.}, the |
1415 | package may actually be built using the @code{guix build} command-line | |
7458bd0a LC |
1416 | tool (@pxref{Invoking guix build}). @xref{Packaging Guidelines}, for |
1417 | more information on how to test package definitions. | |
1418 | ||
1419 | Eventually, updating the package definition to a new upstream version | |
1420 | can be partly automated by the @command{guix refresh} command | |
1421 | (@pxref{Invoking guix refresh}). | |
3dc1970d LC |
1422 | |
1423 | Behind the scenes, a derivation corresponding to the @code{<package>} | |
1424 | object is first computed by the @code{package-derivation} procedure. | |
834129e0 | 1425 | That derivation is stored in a @code{.drv} file under @file{/gnu/store}. |
ba55b1cb | 1426 | The build actions it prescribes may then be realized by using the |
3dc1970d LC |
1427 | @code{build-derivations} procedure (@pxref{The Store}). |
1428 | ||
1429 | @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}] | |
59688fc4 LC |
1430 | Return the @code{<derivation>} object of @var{package} for @var{system} |
1431 | (@pxref{Derivations}). | |
3dc1970d LC |
1432 | |
1433 | @var{package} must be a valid @code{<package>} object, and @var{system} | |
1434 | must be a string denoting the target system type---e.g., | |
1435 | @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store} | |
1436 | must be a connection to the daemon, which operates on the store | |
1437 | (@pxref{The Store}). | |
1438 | @end deffn | |
568717fd | 1439 | |
9c1edabd LC |
1440 | @noindent |
1441 | @cindex cross-compilation | |
1442 | Similarly, it is possible to compute a derivation that cross-builds a | |
1443 | package for some other system: | |
1444 | ||
1445 | @deffn {Scheme Procedure} package-cross-derivation @var{store} @ | |
1446 | @var{package} @var{target} [@var{system}] | |
59688fc4 LC |
1447 | Return the @code{<derivation>} object of @var{package} cross-built from |
1448 | @var{system} to @var{target}. | |
9c1edabd LC |
1449 | |
1450 | @var{target} must be a valid GNU triplet denoting the target hardware | |
1451 | and operating system, such as @code{"mips64el-linux-gnu"} | |
1452 | (@pxref{Configuration Names, GNU configuration triplets,, configure, GNU | |
1453 | Configure and Build System}). | |
1454 | @end deffn | |
1455 | ||
1456 | ||
7458bd0a LC |
1457 | @node Build Systems |
1458 | @section Build Systems | |
1459 | ||
1460 | @cindex build system | |
1461 | Each package definition specifies a @dfn{build system} and arguments for | |
1462 | that build system (@pxref{Defining Packages}). This @code{build-system} | |
1463 | field represents the build procedure of the package, as well implicit | |
1464 | dependencies of that build procedure. | |
1465 | ||
1466 | Build systems are @code{<build-system>} objects. The interface to | |
1467 | create and manipulate them is provided by the @code{(guix build-system)} | |
1468 | module, and actual build systems are exported by specific modules. | |
1469 | ||
1470 | Build systems accept an optional list of @dfn{arguments}. In package | |
1471 | definitions, these are passed @i{via} the @code{arguments} field | |
1472 | (@pxref{Defining Packages}). They are typically keyword arguments | |
1473 | (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU | |
1474 | Guile Reference Manual}). The value of these arguments is usually | |
1475 | evaluated in the @dfn{build stratum}---i.e., by a Guile process launched | |
1476 | by the daemon (@pxref{Derivations}). | |
1477 | ||
1478 | The main build system is @var{gnu-build-system}, which implements the | |
1479 | standard build procedure for GNU packages and many other packages. It | |
1480 | is provided by the @code{(guix build-system gnu)} module. | |
1481 | ||
1482 | @defvr {Scheme Variable} gnu-build-system | |
1483 | @var{gnu-build-system} represents the GNU Build System, and variants | |
1484 | thereof (@pxref{Configuration, configuration and makefile conventions,, | |
1485 | standards, GNU Coding Standards}). | |
1486 | ||
1487 | @cindex build phases | |
1488 | In a nutshell, packages using it configured, built, and installed with | |
1489 | the usual @code{./configure && make && make check && make install} | |
1490 | command sequence. In practice, a few additional steps are often needed. | |
1491 | All these steps are split up in separate @dfn{phases}, | |
1492 | notably@footnote{Please see the @code{(guix build gnu-build-system)} | |
1493 | modules for more details about the build phases.}: | |
1494 | ||
1495 | @table @code | |
1496 | @item unpack | |
1497 | Unpack the source tarball, and change the current directory to the | |
1498 | extracted source tree. If the source is actually a directory, copy it | |
1499 | to the build tree, and enter that directory. | |
1500 | ||
1501 | @item patch-source-shebangs | |
1502 | Patch shebangs encountered in source files so they refer to the right | |
1503 | store file names. For instance, this changes @code{#!/bin/sh} to | |
1504 | @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}. | |
1505 | ||
1506 | @item configure | |
1507 | Run the @file{configure} script with a number of default options, such | |
1508 | as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified | |
1509 | by the @code{#:configure-flags} argument. | |
1510 | ||
1511 | @item build | |
1512 | Run @code{make} with the list of flags specified with | |
1513 | @code{#:make-flags}. If the @code{#:parallel-builds?} argument is true | |
1514 | (the default), build with @code{make -j}. | |
1515 | ||
1516 | @item check | |
1517 | Run @code{make check}, or some other target specified with | |
1518 | @code{#:test-target}, unless @code{#:tests? #f} is passed. If the | |
1519 | @code{#:parallel-tests?} argument is true (the default), run @code{make | |
1520 | check -j}. | |
1521 | ||
1522 | @item install | |
1523 | Run @code{make install} with the flags listed in @code{#:make-flags}. | |
1524 | ||
1525 | @item patch-shebangs | |
1526 | Patch shebangs on the installed executable files. | |
1527 | ||
1528 | @item strip | |
1529 | Strip debugging symbols from ELF files (unless @code{#:strip-binaries?} | |
1530 | is false), copying them to the @code{debug} output when available | |
1531 | (@pxref{Installing Debugging Files}). | |
1532 | @end table | |
1533 | ||
1534 | @vindex %standard-phases | |
1535 | The build-side module @code{(guix build gnu-build-system)} defines | |
1536 | @var{%standard-phases} as the default list of build phases. | |
1537 | @var{%standard-phases} is a list of symbol/procedure pairs, where the | |
1538 | procedure implements the actual phase. | |
1539 | ||
1540 | The list of phases used for a particular package can be changed with the | |
1541 | @code{#:phases} parameter. For instance, passing: | |
1542 | ||
1543 | @example | |
1544 | #:phases (alist-delete 'configure %standard-phases) | |
1545 | @end example | |
1546 | ||
9bf404e9 | 1547 | means that all the phases described above will be used, except the |
7458bd0a LC |
1548 | @code{configure} phase. |
1549 | ||
1550 | In addition, this build system ensures that the ``standard'' environment | |
1551 | for GNU packages is available. This includes tools such as GCC, libc, | |
1552 | Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix | |
1553 | build-system gnu)} module for a complete list.) We call these the | |
1554 | @dfn{implicit inputs} of a package, because package definitions don't | |
1555 | have to mention them. | |
1556 | @end defvr | |
1557 | ||
1558 | Other @code{<build-system>} objects are defined to support other | |
1559 | conventions and tools used by free software packages. They inherit most | |
1560 | of @var{gnu-build-system}, and differ mainly in the set of inputs | |
1561 | implicitly added to the build process, and in the list of phases | |
1562 | executed. Some of these build systems are listed below. | |
1563 | ||
1564 | @defvr {Scheme Variable} cmake-build-system | |
1565 | This variable is exported by @code{(guix build-system cmake)}. It | |
1566 | implements the build procedure for packages using the | |
1567 | @url{http://www.cmake.org, CMake build tool}. | |
1568 | ||
1569 | It automatically adds the @code{cmake} package to the set of inputs. | |
1570 | Which package is used can be specified with the @code{#:cmake} | |
1571 | parameter. | |
1572 | @end defvr | |
1573 | ||
1574 | @defvr {Scheme Variable} python-build-system | |
1575 | This variable is exported by @code{(guix build-system python)}. It | |
1576 | implements the more or less standard build procedure used by Python | |
1577 | packages, which consists in running @code{python setup.py build} and | |
1578 | then @code{python setup.py install --prefix=/gnu/store/@dots{}}. | |
1579 | ||
1580 | For packages that install stand-alone Python programs under @code{bin/}, | |
1581 | it takes care of wrapping these programs so their @code{PYTHONPATH} | |
1582 | environment variable points to all the Python libraries they depend on. | |
1583 | ||
1584 | Which Python package is used can be specified with the @code{#:python} | |
1585 | parameter. | |
1586 | @end defvr | |
1587 | ||
1588 | @defvr {Scheme Variable} perl-build-system | |
1589 | This variable is exported by @code{(guix build-system perl)}. It | |
1590 | implements the standard build procedure for Perl packages, which | |
1591 | consists in running @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, | |
1592 | followed by @code{make} and @code{make install}. | |
1593 | ||
1594 | The initial @code{perl Makefile.PL} invocation passes flags specified by | |
1595 | the @code{#:make-maker-flags} parameter. | |
1596 | ||
1597 | Which Perl package is used can be specified with @code{#:perl}. | |
1598 | @end defvr | |
1599 | ||
1600 | ||
1601 | Lastly, for packages that do not need anything as sophisticated, a | |
1602 | ``trivial'' build system is provided. It is trivial in the sense that | |
1603 | it provides basically no support: it does not pull any implicit inputs, | |
1604 | and does not have a notion of build phases. | |
1605 | ||
1606 | @defvr {Scheme Variable} trivial-build-system | |
1607 | This variable is exported by @code{(guix build-system trivial)}. | |
1608 | ||
1609 | This build system requires a @code{#:builder} argument. This argument | |
1610 | must be a Scheme expression that builds the package's output(s)---as | |
1611 | with @code{build-expression->derivation} (@pxref{Derivations, | |
1612 | @code{build-expression->derivation}}). | |
1613 | @end defvr | |
1614 | ||
568717fd LC |
1615 | @node The Store |
1616 | @section The Store | |
1617 | ||
e531ac2a LC |
1618 | @cindex store |
1619 | @cindex store paths | |
1620 | ||
1621 | Conceptually, the @dfn{store} is where derivations that have been | |
834129e0 | 1622 | successfully built are stored---by default, under @file{/gnu/store}. |
e531ac2a LC |
1623 | Sub-directories in the store are referred to as @dfn{store paths}. The |
1624 | store has an associated database that contains information such has the | |
1625 | store paths referred to by each store path, and the list of @emph{valid} | |
1626 | store paths---paths that result from a successful build. | |
1627 | ||
1628 | The store is always accessed by the daemon on behalf of its clients | |
1629 | (@pxref{Invoking guix-daemon}). To manipulate the store, clients | |
1630 | connect to the daemon over a Unix-domain socket, send it requests, and | |
1631 | read the result---these are remote procedure calls, or RPCs. | |
1632 | ||
1633 | The @code{(guix store)} module provides procedures to connect to the | |
1634 | daemon, and to perform RPCs. These are described below. | |
1635 | ||
1636 | @deffn {Scheme Procedure} open-connection [@var{file}] [#:reserve-space? #t] | |
1637 | Connect to the daemon over the Unix-domain socket at @var{file}. When | |
1638 | @var{reserve-space?} is true, instruct it to reserve a little bit of | |
1639 | extra space on the file system so that the garbage collector can still | |
1640 | operate, should the disk become full. Return a server object. | |
1641 | ||
1642 | @var{file} defaults to @var{%default-socket-path}, which is the normal | |
1643 | location given the options that were passed to @command{configure}. | |
1644 | @end deffn | |
1645 | ||
1646 | @deffn {Scheme Procedure} close-connection @var{server} | |
1647 | Close the connection to @var{server}. | |
1648 | @end deffn | |
1649 | ||
1650 | @defvr {Scheme Variable} current-build-output-port | |
1651 | This variable is bound to a SRFI-39 parameter, which refers to the port | |
1652 | where build and error logs sent by the daemon should be written. | |
1653 | @end defvr | |
1654 | ||
1655 | Procedures that make RPCs all take a server object as their first | |
1656 | argument. | |
1657 | ||
1658 | @deffn {Scheme Procedure} valid-path? @var{server} @var{path} | |
1659 | Return @code{#t} when @var{path} is a valid store path. | |
1660 | @end deffn | |
1661 | ||
cfbf9160 | 1662 | @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}] |
e531ac2a LC |
1663 | Add @var{text} under file @var{name} in the store, and return its store |
1664 | path. @var{references} is the list of store paths referred to by the | |
1665 | resulting store path. | |
1666 | @end deffn | |
1667 | ||
874e6874 | 1668 | @deffn {Scheme Procedure} build-derivations @var{server} @var{derivations} |
59688fc4 LC |
1669 | Build @var{derivations} (a list of @code{<derivation>} objects or |
1670 | derivation paths), and return when the worker is done building them. | |
1671 | Return @code{#t} on success. | |
874e6874 LC |
1672 | @end deffn |
1673 | ||
b860f382 LC |
1674 | Note that the @code{(guix monads)} module provides a monad as well as |
1675 | monadic versions of the above procedures, with the goal of making it | |
1676 | more convenient to work with code that accesses the store (@pxref{The | |
1677 | Store Monad}). | |
1678 | ||
e531ac2a LC |
1679 | @c FIXME |
1680 | @i{This section is currently incomplete.} | |
568717fd LC |
1681 | |
1682 | @node Derivations | |
1683 | @section Derivations | |
1684 | ||
874e6874 LC |
1685 | @cindex derivations |
1686 | Low-level build actions and the environment in which they are performed | |
1687 | are represented by @dfn{derivations}. A derivation contain the | |
1688 | following pieces of information: | |
1689 | ||
1690 | @itemize | |
1691 | @item | |
1692 | The outputs of the derivation---derivations produce at least one file or | |
1693 | directory in the store, but may produce more. | |
1694 | ||
1695 | @item | |
1696 | The inputs of the derivations, which may be other derivations or plain | |
1697 | files in the store (patches, build scripts, etc.) | |
1698 | ||
1699 | @item | |
1700 | The system type targeted by the derivation---e.g., @code{x86_64-linux}. | |
1701 | ||
1702 | @item | |
1703 | The file name of a build script in the store, along with the arguments | |
1704 | to be passed. | |
1705 | ||
1706 | @item | |
1707 | A list of environment variables to be defined. | |
1708 | ||
1709 | @end itemize | |
1710 | ||
1711 | @cindex derivation path | |
1712 | Derivations allow clients of the daemon to communicate build actions to | |
1713 | the store. They exist in two forms: as an in-memory representation, | |
1714 | both on the client- and daemon-side, and as files in the store whose | |
1715 | name end in @code{.drv}---these files are referred to as @dfn{derivation | |
1716 | paths}. Derivations paths can be passed to the @code{build-derivations} | |
1717 | procedure to perform the build actions they prescribe (@pxref{The | |
1718 | Store}). | |
1719 | ||
1720 | The @code{(guix derivations)} module provides a representation of | |
1721 | derivations as Scheme objects, along with procedures to create and | |
1722 | otherwise manipulate derivations. The lowest-level primitive to create | |
1723 | a derivation is the @code{derivation} procedure: | |
1724 | ||
1909431c LC |
1725 | @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @ |
1726 | @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @ | |
2096ef47 | 1727 | [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @ |
1909431c LC |
1728 | [#:system (%current-system)] [#:references-graphs #f] @ |
1729 | [#:local-build? #f] | |
59688fc4 LC |
1730 | Build a derivation with the given arguments, and return the resulting |
1731 | @code{<derivation>} object. | |
874e6874 | 1732 | |
2096ef47 | 1733 | When @var{hash} and @var{hash-algo} are given, a |
874e6874 | 1734 | @dfn{fixed-output derivation} is created---i.e., one whose result is |
36bbbbd1 LC |
1735 | known in advance, such as a file download. If, in addition, |
1736 | @var{recursive?} is true, then that fixed output may be an executable | |
1737 | file or a directory and @var{hash} must be the hash of an archive | |
1738 | containing this output. | |
5b0c9d16 | 1739 | |
858e9282 | 1740 | When @var{references-graphs} is true, it must be a list of file |
5b0c9d16 LC |
1741 | name/store path pairs. In that case, the reference graph of each store |
1742 | path is exported in the build environment in the corresponding file, in | |
1743 | a simple text format. | |
1909431c LC |
1744 | |
1745 | When @var{local-build?} is true, declare that the derivation is not a | |
1746 | good candidate for offloading and should rather be built locally | |
1747 | (@pxref{Daemon Offload Setup}). This is the case for small derivations | |
1748 | where the costs of data transfers would outweigh the benefits. | |
874e6874 LC |
1749 | @end deffn |
1750 | ||
1751 | @noindent | |
1752 | Here's an example with a shell script as its builder, assuming | |
1753 | @var{store} is an open connection to the daemon, and @var{bash} points | |
1754 | to a Bash executable in the store: | |
1755 | ||
1756 | @lisp | |
1757 | (use-modules (guix utils) | |
1758 | (guix store) | |
1759 | (guix derivations)) | |
1760 | ||
59688fc4 LC |
1761 | (let ((builder ; add the Bash script to the store |
1762 | (add-text-to-store store "my-builder.sh" | |
1763 | "echo hello world > $out\n" '()))) | |
1764 | (derivation store "foo" | |
1765 | bash `("-e" ,builder) | |
21b679f6 | 1766 | #:inputs `((,bash) (,builder)) |
59688fc4 | 1767 | #:env-vars '(("HOME" . "/homeless")))) |
834129e0 | 1768 | @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo> |
874e6874 LC |
1769 | @end lisp |
1770 | ||
21b679f6 LC |
1771 | As can be guessed, this primitive is cumbersome to use directly. A |
1772 | better approach is to write build scripts in Scheme, of course! The | |
1773 | best course of action for that is to write the build code as a | |
1774 | ``G-expression'', and to pass it to @code{gexp->derivation}. For more | |
1775 | information, @ref{G-Expressions}. | |
1776 | ||
1777 | Once upon a time, @code{gexp->derivation} did not exist and constructing | |
1778 | derivations with build code written in Scheme was achieved with | |
1779 | @code{build-expression->derivation}, documented below. This procedure | |
1780 | is now deprecated in favor of the much nicer @code{gexp->derivation}. | |
874e6874 | 1781 | |
dd1a5a15 LC |
1782 | @deffn {Scheme Procedure} build-expression->derivation @var{store} @ |
1783 | @var{name} @var{exp} @ | |
1784 | [#:system (%current-system)] [#:inputs '()] @ | |
1785 | [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @ | |
36bbbbd1 | 1786 | [#:recursive? #f] [#:env-vars '()] [#:modules '()] @ |
1909431c | 1787 | [#:references-graphs #f] [#:local-build? #f] [#:guile-for-build #f] |
874e6874 LC |
1788 | Return a derivation that executes Scheme expression @var{exp} as a |
1789 | builder for derivation @var{name}. @var{inputs} must be a list of | |
1790 | @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted, | |
1791 | @code{"out"} is assumed. @var{modules} is a list of names of Guile | |
1792 | modules from the current search path to be copied in the store, | |
1793 | compiled, and made available in the load path during the execution of | |
1794 | @var{exp}---e.g., @code{((guix build utils) (guix build | |
1795 | gnu-build-system))}. | |
1796 | ||
1797 | @var{exp} is evaluated in an environment where @code{%outputs} is bound | |
1798 | to a list of output/path pairs, and where @code{%build-inputs} is bound | |
1799 | to a list of string/output-path pairs made from @var{inputs}. | |
1800 | Optionally, @var{env-vars} is a list of string pairs specifying the name | |
1801 | and value of environment variables visible to the builder. The builder | |
1802 | terminates by passing the result of @var{exp} to @code{exit}; thus, when | |
1803 | @var{exp} returns @code{#f}, the build is considered to have failed. | |
1804 | ||
1805 | @var{exp} is built using @var{guile-for-build} (a derivation). When | |
1806 | @var{guile-for-build} is omitted or is @code{#f}, the value of the | |
1807 | @code{%guile-for-build} fluid is used instead. | |
9c629a27 | 1808 | |
1909431c LC |
1809 | See the @code{derivation} procedure for the meaning of @var{references-graphs} |
1810 | and @var{local-build?}. | |
874e6874 LC |
1811 | @end deffn |
1812 | ||
1813 | @noindent | |
1814 | Here's an example of a single-output derivation that creates a directory | |
1815 | containing one file: | |
1816 | ||
1817 | @lisp | |
1818 | (let ((builder '(let ((out (assoc-ref %outputs "out"))) | |
834129e0 | 1819 | (mkdir out) ; create /gnu/store/@dots{}-goo |
874e6874 LC |
1820 | (call-with-output-file (string-append out "/test") |
1821 | (lambda (p) | |
1822 | (display '(hello guix) p)))))) | |
dd1a5a15 | 1823 | (build-expression->derivation store "goo" builder)) |
874e6874 | 1824 | |
834129e0 | 1825 | @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}> |
874e6874 LC |
1826 | @end lisp |
1827 | ||
568717fd | 1828 | |
b860f382 LC |
1829 | @node The Store Monad |
1830 | @section The Store Monad | |
1831 | ||
1832 | @cindex monad | |
1833 | ||
1834 | The procedures that operate on the store described in the previous | |
1835 | sections all take an open connection to the build daemon as their first | |
1836 | argument. Although the underlying model is functional, they either have | |
1837 | side effects or depend on the current state of the store. | |
1838 | ||
1839 | The former is inconvenient: the connection to the build daemon has to be | |
1840 | carried around in all those functions, making it impossible to compose | |
1841 | functions that do not take that parameter with functions that do. The | |
1842 | latter can be problematic: since store operations have side effects | |
1843 | and/or depend on external state, they have to be properly sequenced. | |
1844 | ||
1845 | @cindex monadic values | |
1846 | @cindex monadic functions | |
1847 | This is where the @code{(guix monads)} module comes in. This module | |
1848 | provides a framework for working with @dfn{monads}, and a particularly | |
1849 | useful monad for our uses, the @dfn{store monad}. Monads are a | |
1850 | construct that allows two things: associating ``context'' with values | |
1851 | (in our case, the context is the store), and building sequences of | |
1852 | computations (here computations includes accesses to the store.) Values | |
1853 | in a monad---values that carry this additional context---are called | |
1854 | @dfn{monadic values}; procedures that return such values are called | |
1855 | @dfn{monadic procedures}. | |
1856 | ||
1857 | Consider this ``normal'' procedure: | |
1858 | ||
1859 | @example | |
45adbd62 LC |
1860 | (define (sh-symlink store) |
1861 | ;; Return a derivation that symlinks the 'bash' executable. | |
1862 | (let* ((drv (package-derivation store bash)) | |
1863 | (out (derivation->output-path drv)) | |
1864 | (sh (string-append out "/bin/bash"))) | |
1865 | (build-expression->derivation store "sh" | |
1866 | `(symlink ,sh %output)))) | |
b860f382 LC |
1867 | @end example |
1868 | ||
1869 | Using @code{(guix monads)}, it may be rewritten as a monadic function: | |
1870 | ||
ada3df03 | 1871 | @c FIXME: Find a better example, one that uses 'mlet'. |
b860f382 | 1872 | @example |
45adbd62 | 1873 | (define (sh-symlink) |
b860f382 | 1874 | ;; Same, but return a monadic value. |
ada3df03 LC |
1875 | (gexp->derivation "sh" |
1876 | #~(symlink (string-append #$bash "/bin/bash") #$output))) | |
b860f382 LC |
1877 | @end example |
1878 | ||
1879 | There are two things to note in the second version: the @code{store} | |
1880 | parameter is now implicit, and the monadic value returned by | |
1881 | @code{package-file}---a wrapper around @code{package-derivation} and | |
1882 | @code{derivation->output-path}---is @dfn{bound} using @code{mlet} | |
1883 | instead of plain @code{let}. | |
1884 | ||
1885 | Calling the monadic @code{profile.sh} has no effect. To get the desired | |
1886 | effect, one must use @code{run-with-store}: | |
1887 | ||
1888 | @example | |
1889 | (run-with-store (open-connection) (profile.sh)) | |
834129e0 | 1890 | @result{} /gnu/store/...-profile.sh |
b860f382 LC |
1891 | @end example |
1892 | ||
1893 | The main syntactic forms to deal with monads in general are described | |
1894 | below. | |
1895 | ||
1896 | @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ... | |
1897 | Evaluate any @code{>>=} or @code{return} forms in @var{body} as being | |
1898 | in @var{monad}. | |
1899 | @end deffn | |
1900 | ||
1901 | @deffn {Scheme Syntax} return @var{val} | |
1902 | Return a monadic value that encapsulates @var{val}. | |
1903 | @end deffn | |
1904 | ||
1905 | @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} | |
1906 | @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic | |
1907 | procedure @var{mproc}@footnote{This operation is commonly referred to as | |
1908 | ``bind'', but that name denotes an unrelated procedure in Guile. Thus | |
1909 | we use this somewhat cryptic symbol inherited from the Haskell | |
1910 | language.}. | |
1911 | @end deffn | |
1912 | ||
1913 | @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @ | |
1914 | @var{body} ... | |
1915 | @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @ | |
1916 | @var{body} ... | |
1917 | Bind the variables @var{var} to the monadic values @var{mval} in | |
1918 | @var{body}. The form (@var{var} -> @var{val}) binds @var{var} to the | |
1919 | ``normal'' value @var{val}, as per @code{let}. | |
1920 | ||
1921 | @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let} | |
1922 | (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}). | |
1923 | @end deffn | |
1924 | ||
1925 | The interface to the store monad provided by @code{(guix monads)} is as | |
1926 | follows. | |
1927 | ||
1928 | @defvr {Scheme Variable} %store-monad | |
1929 | The store monad. Values in the store monad encapsulate accesses to the | |
1930 | store. When its effect is needed, a value of the store monad must be | |
1931 | ``evaluated'' by passing it to the @code{run-with-store} procedure (see | |
1932 | below.) | |
1933 | @end defvr | |
1934 | ||
1935 | @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)] | |
1936 | Run @var{mval}, a monadic value in the store monad, in @var{store}, an | |
1937 | open store connection. | |
1938 | @end deffn | |
1939 | ||
1940 | @deffn {Monadic Procedure} text-file @var{name} @var{text} | |
1941 | Return as a monadic value the absolute file name in the store of the file | |
45adbd62 LC |
1942 | containing @var{text}, a string. |
1943 | @end deffn | |
1944 | ||
1945 | @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{} | |
1946 | Return as a monadic value a derivation that builds a text file | |
1947 | containing all of @var{text}. @var{text} may list, in addition to | |
1948 | strings, packages, derivations, and store file names; the resulting | |
1949 | store file holds references to all these. | |
1950 | ||
1951 | This variant should be preferred over @code{text-file} anytime the file | |
1952 | to create will reference items from the store. This is typically the | |
1953 | case when building a configuration file that embeds store file names, | |
1954 | like this: | |
1955 | ||
1956 | @example | |
1957 | (define (profile.sh) | |
1958 | ;; Return the name of a shell script in the store that | |
1959 | ;; initializes the 'PATH' environment variable. | |
1960 | (text-file* "profile.sh" | |
1961 | "export PATH=" coreutils "/bin:" | |
1962 | grep "/bin:" sed "/bin\n")) | |
1963 | @end example | |
1964 | ||
834129e0 | 1965 | In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file |
45adbd62 LC |
1966 | will references @var{coreutils}, @var{grep}, and @var{sed}, thereby |
1967 | preventing them from being garbage-collected during its lifetime. | |
b860f382 LC |
1968 | @end deffn |
1969 | ||
1970 | @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @ | |
1971 | [#:system (%current-system)] [#:output "out"] Return as a monadic | |
1972 | value in the absolute file name of @var{file} within the @var{output} | |
1973 | directory of @var{package}. When @var{file} is omitted, return the name | |
1974 | of the @var{output} directory of @var{package}. | |
1975 | @end deffn | |
1976 | ||
b860f382 LC |
1977 | @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}] |
1978 | Monadic version of @code{package-derivation} (@pxref{Defining | |
1979 | Packages}). | |
1980 | @end deffn | |
1981 | ||
1982 | ||
21b679f6 LC |
1983 | @node G-Expressions |
1984 | @section G-Expressions | |
1985 | ||
1986 | @cindex G-expression | |
1987 | @cindex build code quoting | |
1988 | So we have ``derivations'', which represent a sequence of build actions | |
1989 | to be performed to produce an item in the store (@pxref{Derivations}). | |
1990 | Those build actions are performed when asking the daemon to actually | |
1991 | build the derivations; they are run by the daemon in a container | |
1992 | (@pxref{Invoking guix-daemon}). | |
1993 | ||
1994 | @cindex strata of code | |
1995 | It should come as no surprise that we like to write those build actions | |
1996 | in Scheme. When we do that, we end up with two @dfn{strata} of Scheme | |
1997 | code@footnote{The term @dfn{stratum} in this context was coined by | |
1998 | Manuel Serrano et al.@: in the context of their work on Hop.}: the | |
1999 | ``host code''---code that defines packages, talks to the daemon, | |
2000 | etc.---and the ``build code''---code that actually performs build | |
2001 | actions, such as making directories, invoking @command{make}, etc. | |
2002 | ||
2003 | To describe a derivation and its build actions, one typically needs to | |
2004 | embed build code inside host code. It boils down to manipulating build | |
2005 | code as data, and Scheme's homoiconicity---code has a direct | |
2006 | representation as data---comes in handy for that. But we need more than | |
2007 | Scheme's normal @code{quasiquote} mechanism to construct build | |
2008 | expressions. | |
2009 | ||
2010 | The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of | |
2011 | S-expressions adapted to build expressions. G-expressions, or | |
2012 | @dfn{gexps}, consist essentially in three syntactic forms: @code{gexp}, | |
2013 | @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~}, | |
2014 | @code{#$}, and @code{#$@@}), which are comparable respectively to | |
2015 | @code{quasiquote}, @code{unquote}, and @code{unquote-splicing} | |
2016 | (@pxref{Expression Syntax, @code{quasiquote},, guile, GNU Guile | |
2017 | Reference Manual}). However, there are major differences: | |
2018 | ||
2019 | @itemize | |
2020 | @item | |
2021 | Gexps are meant to be written to a file and run or manipulated by other | |
2022 | processes. | |
2023 | ||
2024 | @item | |
2025 | When a package or derivation is unquoted inside a gexp, the result is as | |
2026 | if its output file name had been introduced. | |
2027 | ||
2028 | @item | |
2029 | Gexps carry information about the packages or derivations they refer to, | |
2030 | and these dependencies are automatically added as inputs to the build | |
2031 | processes that use them. | |
2032 | @end itemize | |
2033 | ||
2034 | To illustrate the idea, here is an example of a gexp: | |
2035 | ||
2036 | @example | |
2037 | (define build-exp | |
2038 | #~(begin | |
2039 | (mkdir #$output) | |
2040 | (chdir #$output) | |
2041 | (symlink (string-append #$coreutils "/bin/ls") | |
2042 | "list-files"))) | |
2043 | @end example | |
2044 | ||
2045 | This gexp can be passed to @code{gexp->derivation}; we obtain a | |
2046 | derivation that builds a directory containing exactly one symlink to | |
2047 | @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}: | |
2048 | ||
2049 | @example | |
2050 | (gexp->derivation "the-thing" build-exp) | |
2051 | @end example | |
2052 | ||
2053 | As one would expect, the @code{"/gnu/store/@dots{}-coreutils"} string is | |
2054 | substituted to the reference to the @var{coreutils} package in the | |
2055 | actual build code, and @var{coreutils} is automatically made an input to | |
2056 | the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp | |
2057 | output)}) is replaced by a string containing the derivation's output | |
2058 | directory name. The syntactic form to construct gexps is summarized | |
2059 | below. | |
2060 | ||
2061 | @deffn {Scheme Syntax} #~@var{exp} | |
2062 | @deffnx {Scheme Syntax} (gexp @var{exp}) | |
2063 | Return a G-expression containing @var{exp}. @var{exp} may contain one | |
2064 | or more of the following forms: | |
2065 | ||
2066 | @table @code | |
2067 | @item #$@var{obj} | |
2068 | @itemx (ungexp @var{obj}) | |
2069 | Introduce a reference to @var{obj}. @var{obj} may be a package or a | |
2070 | derivation, in which case the @code{ungexp} form is replaced by its | |
2071 | output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}. | |
2072 | ||
2073 | If @var{obj} is a list, it is traversed and any package or derivation | |
2074 | references are substituted similarly. | |
2075 | ||
2076 | If @var{obj} is another gexp, its contents are inserted and its | |
2077 | dependencies are added to those of the containing gexp. | |
2078 | ||
2079 | If @var{obj} is another kind of object, it is inserted as is. | |
2080 | ||
2081 | @item #$@var{package-or-derivation}:@var{output} | |
2082 | @itemx (ungexp @var{package-or-derivation} @var{output}) | |
2083 | This is like the form above, but referring explicitly to the | |
2084 | @var{output} of @var{package-or-derivation}---this is useful when | |
2085 | @var{package-or-derivation} produces multiple outputs (@pxref{Packages | |
2086 | with Multiple Outputs}). | |
2087 | ||
2088 | @item #$output[:@var{output}] | |
2089 | @itemx (ungexp output [@var{output}]) | |
2090 | Insert a reference to derivation output @var{output}, or to the main | |
2091 | output when @var{output} is omitted. | |
2092 | ||
2093 | This only makes sense for gexps passed to @code{gexp->derivation}. | |
2094 | ||
2095 | @item #$@@@var{lst} | |
2096 | @itemx (ungexp-splicing @var{lst}) | |
2097 | Like the above, but splices the contents of @var{lst} inside the | |
2098 | containing list. | |
2099 | ||
2100 | @end table | |
2101 | ||
2102 | G-expressions created by @code{gexp} or @code{#~} are run-time objects | |
2103 | of the @code{gexp?} type (see below.) | |
2104 | @end deffn | |
2105 | ||
2106 | @deffn {Scheme Procedure} gexp? @var{obj} | |
2107 | Return @code{#t} if @var{obj} is a G-expression. | |
2108 | @end deffn | |
2109 | ||
2110 | G-expressions are meant to be written to disk, either as code building | |
2111 | some derivation, or as plain files in the store. The monadic procedures | |
2112 | below allow you to do that (@pxref{The Store Monad}, for more | |
2113 | information about monads.) | |
2114 | ||
2115 | @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @ | |
2116 | [#:system (%current-system)] [#:inputs '()] @ | |
2117 | [#:hash #f] [#:hash-algo #f] @ | |
2118 | [#:recursive? #f] [#:env-vars '()] [#:modules '()] @ | |
2119 | [#:references-graphs #f] [#:local-build? #f] @ | |
2120 | [#:guile-for-build #f] | |
2121 | Return a derivation @var{name} that runs @var{exp} (a gexp) with | |
2122 | @var{guile-for-build} (a derivation) on @var{system}. | |
2123 | ||
2124 | Make @var{modules} available in the evaluation context of @var{EXP}; | |
2125 | @var{MODULES} is a list of names of Guile modules from the current | |
2126 | search path to be copied in the store, compiled, and made available in | |
2127 | the load path during the execution of @var{exp}---e.g., @code{((guix | |
2128 | build utils) (guix build gnu-build-system))}. | |
2129 | ||
2130 | The other arguments are as for @code{derivation}. | |
2131 | @end deffn | |
2132 | ||
2133 | @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} | |
2134 | Return an executable script @var{name} that runs @var{exp} using | |
2135 | @var{guile} with @var{modules} in its search path. | |
2136 | ||
2137 | The example below builds a script that simply invokes the @command{ls} | |
2138 | command: | |
2139 | ||
2140 | @example | |
2141 | (use-modules (guix gexp) (gnu packages base)) | |
2142 | ||
2143 | (gexp->script "list-files" | |
2144 | #~(execl (string-append #$coreutils "/bin/ls") | |
2145 | "ls")) | |
2146 | @end example | |
2147 | ||
2148 | When ``running'' it through the store (@pxref{The Store Monad, | |
2149 | @code{run-with-store}}), we obtain a derivation that procedures an | |
2150 | executable file @file{/gnu/store/@dots{}-list-files} along these lines: | |
2151 | ||
2152 | @example | |
2153 | #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds | |
2154 | !# | |
2155 | (execl (string-append "/gnu/store/@dots{}-coreutils-8.22"/bin/ls") | |
2156 | "ls") | |
2157 | @end example | |
2158 | @end deffn | |
2159 | ||
2160 | @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} | |
2161 | Return a derivation that builds a file @var{name} containing @var{exp}. | |
2162 | ||
2163 | The resulting file holds references to all the dependencies of @var{exp} | |
2164 | or a subset thereof. | |
2165 | @end deffn | |
2166 | ||
2167 | Of course, in addition to gexps embedded in ``host'' code, there are | |
2168 | also modules containing build tools. To make it clear that they are | |
2169 | meant to be used in the build stratum, these modules are kept in the | |
2170 | @code{(guix build @dots{})} name space. | |
2171 | ||
2172 | ||
568717fd LC |
2173 | @c ********************************************************************* |
2174 | @node Utilities | |
2175 | @chapter Utilities | |
2176 | ||
210cc920 LC |
2177 | This section describes tools primarily targeted at developers and users |
2178 | who write new package definitions. They complement the Scheme | |
2179 | programming interface of Guix in a convenient way. | |
2180 | ||
568717fd | 2181 | @menu |
37166310 | 2182 | * Invoking guix build:: Building packages from the command line. |
210cc920 | 2183 | * Invoking guix download:: Downloading a file and printing its hash. |
37166310 LC |
2184 | * Invoking guix hash:: Computing the cryptographic hash of a file. |
2185 | * Invoking guix refresh:: Updating package definitions. | |
568717fd LC |
2186 | @end menu |
2187 | ||
e49951eb MW |
2188 | @node Invoking guix build |
2189 | @section Invoking @command{guix build} | |
568717fd | 2190 | |
e49951eb | 2191 | The @command{guix build} command builds packages or derivations and |
6798a8e4 LC |
2192 | their dependencies, and prints the resulting store paths. Note that it |
2193 | does not modify the user's profile---this is the job of the | |
e49951eb | 2194 | @command{guix package} command (@pxref{Invoking guix package}). Thus, |
6798a8e4 LC |
2195 | it is mainly useful for distribution developers. |
2196 | ||
2197 | The general syntax is: | |
c78bd12b LC |
2198 | |
2199 | @example | |
e49951eb | 2200 | guix build @var{options} @var{package-or-derivation}@dots{} |
c78bd12b LC |
2201 | @end example |
2202 | ||
2203 | @var{package-or-derivation} may be either the name of a package found in | |
5401dd75 LC |
2204 | the software distribution such as @code{coreutils} or |
2205 | @code{coreutils-8.20}, or a derivation such as | |
834129e0 | 2206 | @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a |
e7f34eb0 LC |
2207 | package with the corresponding name (and optionally version) is searched |
2208 | for among the GNU distribution modules (@pxref{Package Modules}). | |
2209 | ||
2210 | Alternatively, the @code{--expression} option may be used to specify a | |
2211 | Scheme expression that evaluates to a package; this is useful when | |
2212 | disambiguation among several same-named packages or package variants is | |
2213 | needed. | |
c78bd12b LC |
2214 | |
2215 | The @var{options} may be zero or more of the following: | |
2216 | ||
2217 | @table @code | |
2218 | ||
2219 | @item --expression=@var{expr} | |
2220 | @itemx -e @var{expr} | |
ac5de156 | 2221 | Build the package or derivation @var{expr} evaluates to. |
c78bd12b | 2222 | |
5401dd75 | 2223 | For example, @var{expr} may be @code{(@@ (gnu packages guile) |
c78bd12b LC |
2224 | guile-1.8)}, which unambiguously designates this specific variant of |
2225 | version 1.8 of Guile. | |
2226 | ||
ac5de156 LC |
2227 | Alternately, @var{expr} may refer to a zero-argument monadic procedure |
2228 | (@pxref{The Store Monad}). The procedure must return a derivation as a | |
2229 | monadic value, which is then passed through @code{run-with-store}. | |
2230 | ||
c78bd12b LC |
2231 | @item --source |
2232 | @itemx -S | |
2233 | Build the packages' source derivations, rather than the packages | |
2234 | themselves. | |
2235 | ||
e49951eb | 2236 | For instance, @code{guix build -S gcc} returns something like |
834129e0 | 2237 | @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is GCC's source tarball. |
c78bd12b | 2238 | |
f9cc8971 LC |
2239 | The returned source tarball is the result of applying any patches and |
2240 | code snippets specified in the package's @code{origin} (@pxref{Defining | |
2241 | Packages}). | |
2242 | ||
c78bd12b LC |
2243 | @item --system=@var{system} |
2244 | @itemx -s @var{system} | |
2245 | Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of | |
2246 | the host's system type. | |
2247 | ||
2248 | An example use of this is on Linux-based systems, which can emulate | |
2249 | different personalities. For instance, passing | |
2250 | @code{--system=i686-linux} on an @code{x86_64-linux} system allows users | |
2251 | to build packages in a complete 32-bit environment. | |
2252 | ||
e55ec43d LC |
2253 | @item --target=@var{triplet} |
2254 | @cindex cross-compilation | |
2255 | Cross-build for @var{triplet}, which must be a valid GNU triplet, such | |
2256 | as @code{"mips64el-linux-gnu"} (@pxref{Configuration Names, GNU | |
2257 | configuration triplets,, configure, GNU Configure and Build System}). | |
2258 | ||
7f3673f2 LC |
2259 | @item --with-source=@var{source} |
2260 | Use @var{source} as the source of the corresponding package. | |
2261 | @var{source} must be a file name or a URL, as for @command{guix | |
2262 | download} (@pxref{Invoking guix download}). | |
2263 | ||
2264 | The ``corresponding package'' is taken to be one specified on the | |
2265 | command line whose name matches the base of @var{source}---e.g., if | |
2266 | @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding | |
2267 | package is @code{guile}. Likewise, the version string is inferred from | |
2268 | @var{source}; in the previous example, it's @code{2.0.10}. | |
2269 | ||
2270 | This option allows users to try out versions of packages other than the | |
2271 | one provided by the distribution. The example below downloads | |
2272 | @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for | |
2273 | the @code{ed} package: | |
2274 | ||
2275 | @example | |
2276 | guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz | |
2277 | @end example | |
2278 | ||
2279 | As a developer, @code{--with-source} makes it easy to test release | |
2280 | candidates: | |
2281 | ||
2282 | @example | |
2283 | guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz | |
2284 | @end example | |
2285 | ||
2286 | ||
c78bd12b LC |
2287 | @item --derivations |
2288 | @itemx -d | |
2289 | Return the derivation paths, not the output paths, of the given | |
2290 | packages. | |
2291 | ||
70ee5642 LC |
2292 | @item --root=@var{file} |
2293 | @itemx -r @var{file} | |
2294 | Make @var{file} a symlink to the result, and register it as a garbage | |
2295 | collector root. | |
2296 | ||
2297 | @item --log-file | |
2298 | Return the build log file names for the given | |
2299 | @var{package-or-derivation}s, or raise an error if build logs are | |
2300 | missing. | |
2301 | ||
2302 | This works regardless of how packages or derivations are specified. For | |
2303 | instance, the following invocations are equivalent: | |
2304 | ||
2305 | @example | |
2306 | guix build --log-file `guix build -d guile` | |
2307 | guix build --log-file `guix build guile` | |
2308 | guix build --log-file guile | |
2309 | guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)' | |
2310 | @end example | |
2311 | ||
2312 | ||
2313 | @end table | |
2314 | ||
2315 | @cindex common build options | |
2316 | In addition, a number of options that control the build process are | |
2317 | common to @command{guix build} and other commands that can spawn builds, | |
2318 | such as @command{guix package} or @command{guix archive}. These are the | |
2319 | following: | |
2320 | ||
2321 | @table @code | |
2322 | ||
c78bd12b LC |
2323 | @item --keep-failed |
2324 | @itemx -K | |
2325 | Keep the build tree of failed builds. Thus, if a build fail, its build | |
2326 | tree is kept under @file{/tmp}, in a directory whose name is shown at | |
2327 | the end of the build log. This is useful when debugging build issues. | |
2328 | ||
2329 | @item --dry-run | |
2330 | @itemx -n | |
2331 | Do not build the derivations. | |
2332 | ||
56b1f4b7 LC |
2333 | @item --fallback |
2334 | When substituting a pre-built binary fails, fall back to building | |
2335 | packages locally. | |
2336 | ||
c78bd12b | 2337 | @item --no-substitutes |
b5385b52 | 2338 | Do not use substitutes for build products. That is, always build things |
c4202d60 LC |
2339 | locally instead of allowing downloads of pre-built binaries |
2340 | (@pxref{Substitutes}). | |
c78bd12b | 2341 | |
425b0bfc | 2342 | @item --no-build-hook |
4ec2e92d LC |
2343 | Do not attempt to offload builds @i{via} the daemon's ``build hook'' |
2344 | (@pxref{Daemon Offload Setup}). That is, always build things locally | |
2345 | instead of offloading builds to remote machines. | |
425b0bfc | 2346 | |
969e678e LC |
2347 | @item --max-silent-time=@var{seconds} |
2348 | When the build or substitution process remains silent for more than | |
2349 | @var{seconds}, terminate it and report a build failure. | |
2350 | ||
002622b6 LC |
2351 | @item --timeout=@var{seconds} |
2352 | Likewise, when the build or substitution process lasts for more than | |
2353 | @var{seconds}, terminate it and report a build failure. | |
2354 | ||
2355 | By default there is no timeout. This behavior can be restored with | |
2356 | @code{--timeout=0}. | |
2357 | ||
07ab4bf1 LC |
2358 | @item --verbosity=@var{level} |
2359 | Use the given verbosity level. @var{level} must be an integer between 0 | |
2360 | and 5; higher means more verbose output. Setting a level of 4 or more | |
2361 | may be helpful when debugging setup issues with the build daemon. | |
2362 | ||
70ee5642 LC |
2363 | @item --cores=@var{n} |
2364 | @itemx -c @var{n} | |
2365 | Allow the use of up to @var{n} CPU cores for the build. The special | |
2366 | value @code{0} means to use as many CPU cores as available. | |
bf421152 | 2367 | |
c78bd12b LC |
2368 | @end table |
2369 | ||
e49951eb | 2370 | Behind the scenes, @command{guix build} is essentially an interface to |
c78bd12b LC |
2371 | the @code{package-derivation} procedure of the @code{(guix packages)} |
2372 | module, and to the @code{build-derivations} procedure of the @code{(guix | |
2373 | store)} module. | |
2374 | ||
210cc920 LC |
2375 | @node Invoking guix download |
2376 | @section Invoking @command{guix download} | |
2377 | ||
2378 | When writing a package definition, developers typically need to download | |
2379 | the package's source tarball, compute its SHA256 hash, and write that | |
2380 | hash in the package definition (@pxref{Defining Packages}). The | |
2381 | @command{guix download} tool helps with this task: it downloads a file | |
2382 | from the given URI, adds it to the store, and prints both its file name | |
2383 | in the store and its SHA256 hash. | |
2384 | ||
2385 | The fact that the downloaded file is added to the store saves bandwidth: | |
2386 | when the developer eventually tries to build the newly defined package | |
2387 | with @command{guix build}, the source tarball will not have to be | |
2388 | downloaded again because it is already in the store. It is also a | |
2389 | convenient way to temporarily stash files, which may be deleted | |
2390 | eventually (@pxref{Invoking guix gc}). | |
2391 | ||
2392 | The @command{guix download} command supports the same URIs as used in | |
2393 | package definitions. In particular, it supports @code{mirror://} URIs. | |
2394 | @code{https} URIs (HTTP over TLS) are supported @emph{provided} the | |
2395 | Guile bindings for GnuTLS are available in the user's environment; when | |
2396 | they are not available, an error is raised. | |
2397 | ||
2398 | The following option is available: | |
2399 | ||
2400 | @table @code | |
2401 | @item --format=@var{fmt} | |
2402 | @itemx -f @var{fmt} | |
2403 | Write the hash in the format specified by @var{fmt}. For more | |
2404 | information on the valid values for @var{fmt}, @ref{Invoking guix hash}. | |
2405 | @end table | |
2406 | ||
6c365eca NK |
2407 | @node Invoking guix hash |
2408 | @section Invoking @command{guix hash} | |
2409 | ||
210cc920 | 2410 | The @command{guix hash} command computes the SHA256 hash of a file. |
6c365eca NK |
2411 | It is primarily a convenience tool for anyone contributing to the |
2412 | distribution: it computes the cryptographic hash of a file, which can be | |
2413 | used in the definition of a package (@pxref{Defining Packages}). | |
2414 | ||
2415 | The general syntax is: | |
2416 | ||
2417 | @example | |
2418 | guix hash @var{option} @var{file} | |
2419 | @end example | |
2420 | ||
2421 | @command{guix hash} has the following option: | |
2422 | ||
2423 | @table @code | |
2424 | ||
2425 | @item --format=@var{fmt} | |
2426 | @itemx -f @var{fmt} | |
210cc920 | 2427 | Write the hash in the format specified by @var{fmt}. |
6c365eca NK |
2428 | |
2429 | Supported formats: @code{nix-base32}, @code{base32}, @code{base16} | |
2430 | (@code{hex} and @code{hexadecimal} can be used as well). | |
2431 | ||
2432 | If the @option{--format} option is not specified, @command{guix hash} | |
2433 | will output the hash in @code{nix-base32}. This representation is used | |
2434 | in the definitions of packages. | |
2435 | ||
3140f2df LC |
2436 | @item --recursive |
2437 | @itemx -r | |
2438 | Compute the hash on @var{file} recursively. | |
2439 | ||
2440 | In this case, the hash is computed on an archive containing @var{file}, | |
2441 | including its children if it is a directory. Some of @var{file}'s | |
2442 | meta-data is part of the archive; for instance, when @var{file} is a | |
2443 | regular file, the hash is different depending on whether @var{file} is | |
2444 | executable or not. Meta-data such as time stamps has no impact on the | |
2445 | hash (@pxref{Invoking guix archive}). | |
2446 | @c FIXME: Replace xref above with xref to an ``Archive'' section when | |
2447 | @c it exists. | |
2448 | ||
6c365eca NK |
2449 | @end table |
2450 | ||
37166310 LC |
2451 | @node Invoking guix refresh |
2452 | @section Invoking @command{guix refresh} | |
2453 | ||
2454 | The primary audience of the @command{guix refresh} command is developers | |
2455 | of the GNU software distribution. By default, it reports any packages | |
2456 | provided by the distribution that are outdated compared to the latest | |
2457 | upstream version, like this: | |
2458 | ||
2459 | @example | |
2460 | $ guix refresh | |
2461 | gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1 | |
2462 | gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0 | |
2463 | @end example | |
2464 | ||
2465 | It does so by browsing each package's FTP directory and determining the | |
2466 | highest version number of the source tarballs | |
2467 | therein@footnote{Currently, this only works for GNU packages.}. | |
2468 | ||
2469 | When passed @code{--update}, it modifies distribution source files to | |
2470 | update the version numbers and source tarball hashes of those packages' | |
2471 | recipes (@pxref{Defining Packages}). This is achieved by downloading | |
2472 | each package's latest source tarball and its associated OpenPGP | |
2473 | signature, authenticating the downloaded tarball against its signature | |
2474 | using @command{gpg}, and finally computing its hash. When the public | |
2475 | key used to sign the tarball is missing from the user's keyring, an | |
2476 | attempt is made to automatically retrieve it from a public key server; | |
2477 | when it's successful, the key is added to the user's keyring; otherwise, | |
2478 | @command{guix refresh} reports an error. | |
2479 | ||
2480 | The following options are supported: | |
2481 | ||
2482 | @table @code | |
2483 | ||
2484 | @item --update | |
2485 | @itemx -u | |
2486 | Update distribution source files (package recipes) in place. | |
2487 | @ref{Defining Packages}, for more information on package definitions. | |
2488 | ||
2489 | @item --select=[@var{subset}] | |
2490 | @itemx -s @var{subset} | |
2491 | Select all the packages in @var{subset}, one of @code{core} or | |
2492 | @code{non-core}. | |
2493 | ||
2494 | The @code{core} subset refers to all the packages at the core of the | |
2495 | distribution---i.e., packages that are used to build ``everything | |
2496 | else''. This includes GCC, libc, Binutils, Bash, etc. Usually, | |
2497 | changing one of these packages in the distribution entails a rebuild of | |
2498 | all the others. Thus, such updates are an inconvenience to users in | |
2499 | terms of build time or bandwidth used to achieve the upgrade. | |
2500 | ||
2501 | The @code{non-core} subset refers to the remaining packages. It is | |
2502 | typically useful in cases where an update of the core packages would be | |
2503 | inconvenient. | |
2504 | ||
2505 | @end table | |
2506 | ||
2507 | In addition, @command{guix refresh} can be passed one or more package | |
2508 | names, as in this example: | |
2509 | ||
2510 | @example | |
2511 | guix refresh -u emacs idutils | |
2512 | @end example | |
2513 | ||
2514 | @noindent | |
2515 | The command above specifically updates the @code{emacs} and | |
2516 | @code{idutils} packages. The @code{--select} option would have no | |
2517 | effect in this case. | |
2518 | ||
f9230085 LC |
2519 | The following options can be used to customize GnuPG operation: |
2520 | ||
2521 | @table @code | |
2522 | ||
2523 | @item --key-server=@var{host} | |
2524 | Use @var{host} as the OpenPGP key server when importing a public key. | |
2525 | ||
2526 | @item --gpg=@var{command} | |
2527 | Use @var{command} as the GnuPG 2.x command. @var{command} is searched | |
2528 | for in @code{$PATH}. | |
2529 | ||
2530 | @end table | |
2531 | ||
37166310 | 2532 | |
a1ba8475 LC |
2533 | @c ********************************************************************* |
2534 | @node GNU Distribution | |
2535 | @chapter GNU Distribution | |
2536 | ||
2537 | Guix comes with a distribution of free software@footnote{The term | |
2538 | ``free'' here refers to the | |
2539 | @url{http://www.gnu.org/philosophy/free-sw.html,freedom provided to | |
c320011d | 2540 | users of that software}.} that forms the basis of the GNU system. This |
a1ba8475 LC |
2541 | includes core GNU packages such as GNU libc, GCC, and Binutils, as well |
2542 | as many GNU and non-GNU applications. The complete list of available | |
d03bb653 LC |
2543 | packages can be browsed |
2544 | @url{http://www.gnu.org/software/guix/package-list.html,on-line} or by | |
2545 | running @command{guix package} (@pxref{Invoking guix package}): | |
a1ba8475 LC |
2546 | |
2547 | @example | |
e49951eb | 2548 | guix package --list-available |
a1ba8475 LC |
2549 | @end example |
2550 | ||
401c53c4 LC |
2551 | Our goal is to build a practical 100% free software distribution of |
2552 | Linux-based and other variants of GNU, with a focus on the promotion and | |
2553 | tight integration of GNU components, and an emphasis on programs and | |
2554 | tools that help users exert that freedom. | |
2555 | ||
c320011d LC |
2556 | The GNU distribution is currently available on the following platforms: |
2557 | ||
2558 | @table @code | |
2559 | ||
2560 | @item x86_64-linux | |
2561 | Intel/AMD @code{x86_64} architecture, Linux-Libre kernel; | |
2562 | ||
2563 | @item i686-linux | |
2564 | Intel 32-bit architecture (IA32), Linux-Libre kernel; | |
2565 | ||
2566 | @item mips64el-linux | |
2567 | little-endian 64-bit MIPS processors, specifically the Loongson series, | |
2568 | n32 application binary interface (ABI), and Linux-Libre kernel. | |
2569 | ||
2570 | @end table | |
2571 | ||
2572 | @noindent | |
2573 | For information on porting to other architectures or kernels, | |
2574 | @xref{Porting}. | |
2575 | ||
401c53c4 | 2576 | @menu |
91ef73d4 | 2577 | * Installing Debugging Files:: Feeding the debugger. |
401c53c4 | 2578 | * Package Modules:: Packages from the programmer's viewpoint. |
da7cabd4 | 2579 | * Packaging Guidelines:: Growing the distribution. |
401c53c4 | 2580 | * Bootstrapping:: GNU/Linux built from scratch. |
8b315a6d | 2581 | * Porting:: Targeting another platform or kernel. |
4af2447e | 2582 | * System Configuration:: Configuring a GNU system. |
401c53c4 LC |
2583 | @end menu |
2584 | ||
2585 | Building this distribution is a cooperative effort, and you are invited | |
2586 | to join! @ref{Contributing}, for information about how you can help. | |
2587 | ||
b208a005 | 2588 | |
91ef73d4 LC |
2589 | @node Installing Debugging Files |
2590 | @section Installing Debugging Files | |
2591 | ||
2592 | Program binaries, as produced by the GCC compilers for instance, are | |
2593 | typically written in the ELF format, with a section containing | |
2594 | @dfn{debugging information}. Debugging information is what allows the | |
2595 | debugger, GDB, to map binary code to source code; it is required to | |
2596 | debug a compiled program in good conditions. | |
2597 | ||
2598 | The problem with debugging information is that is takes up a fair amount | |
2599 | of disk space. For example, debugging information for the GNU C Library | |
2600 | weighs in at more than 60 MiB. Thus, as a user, keeping all the | |
2601 | debugging info of all the installed programs is usually not an option. | |
2602 | Yet, space savings should not come at the cost of an impediment to | |
2603 | debugging---especially in the GNU system, which should make it easier | |
2604 | for users to exert their computing freedom (@pxref{GNU Distribution}). | |
2605 | ||
2606 | Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a | |
2607 | mechanism that allows users to get the best of both worlds: debugging | |
2608 | information can be stripped from the binaries and stored in separate | |
2609 | files. GDB is then able to load debugging information from those files, | |
2610 | when they are available (@pxref{Separate Debug Files,,, gdb, Debugging | |
2611 | with GDB}). | |
2612 | ||
2613 | The GNU distribution takes advantage of this by storing debugging | |
2614 | information in the @code{lib/debug} sub-directory of a separate package | |
2615 | output unimaginatively called @code{debug} (@pxref{Packages with | |
2616 | Multiple Outputs}). Users can choose to install the @code{debug} output | |
2617 | of a package when they need it. For instance, the following command | |
2618 | installs the debugging information for the GNU C Library and for GNU | |
2619 | Guile: | |
2620 | ||
2621 | @example | |
2622 | guix package -i glibc:debug -i guile:debug | |
2623 | @end example | |
2624 | ||
2625 | GDB must then be told to look for debug files in the user's profile, by | |
2626 | setting the @code{debug-file-directory} variable (consider setting it | |
2627 | from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with | |
2628 | GDB}): | |
2629 | ||
2630 | @example | |
2631 | (gdb) set debug-file-directory ~/.guix-profile/lib/debug | |
2632 | @end example | |
2633 | ||
2634 | From there on, GDB will pick up debugging information from the | |
2635 | @code{.debug} files under @file{~/.guix-profile/lib/debug}. | |
2636 | ||
2637 | @c XXX: keep me up-to-date | |
2638 | The @code{debug} output mechanism in Guix is implemented by the | |
2639 | @code{gnu-build-system} (@pxref{Defining Packages}). Currently, it is | |
2640 | opt-in---debugging information is available only for those packages | |
2641 | whose definition explicitly declares a @code{debug} output. This may be | |
2642 | changed to opt-out in the future, if our build farm servers can handle | |
2643 | the load. To check whether a package has a @code{debug} output, use | |
2644 | @command{guix package --list-available} (@pxref{Invoking guix package}). | |
2645 | ||
2646 | ||
401c53c4 LC |
2647 | @node Package Modules |
2648 | @section Package Modules | |
2649 | ||
2650 | From a programming viewpoint, the package definitions of the | |
e7f34eb0 | 2651 | GNU distribution are provided by Guile modules in the @code{(gnu packages |
7e17f65d LC |
2652 | @dots{})} name space@footnote{Note that packages under the @code{(gnu |
2653 | packages @dots{})} module name space are not necessarily ``GNU | |
2654 | packages''. This module naming scheme follows the usual Guile module | |
2655 | naming convention: @code{gnu} means that these modules are distributed | |
2656 | as part of the GNU system, and @code{packages} identifies modules that | |
2657 | define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile | |
b81e1947 LC |
2658 | Reference Manual}). For instance, the @code{(gnu packages emacs)} |
2659 | module exports a variable named @code{emacs}, which is bound to a | |
e7f34eb0 LC |
2660 | @code{<package>} object (@pxref{Defining Packages}). |
2661 | ||
2662 | The @code{(gnu packages @dots{})} module name space is special: it is | |
2663 | automatically scanned for packages by the command-line tools. For | |
2664 | instance, when running @code{guix package -i emacs}, all the @code{(gnu | |
2665 | packages @dots{})} modules are scanned until one that exports a package | |
2666 | object whose name is @code{emacs} is found. This package search | |
2667 | facility is implemented in the @code{(gnu packages)} module. | |
2668 | ||
2669 | Users can store package definitions in modules with different | |
2670 | names---e.g., @code{(my-packages emacs)}. In that case, commands such | |
2671 | as @command{guix package} and @command{guix build} have to be used with | |
2672 | the @code{-e} option so that they know where to find the package. | |
a1ba8475 LC |
2673 | |
2674 | The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}: | |
2675 | each package is built based solely on other packages in the | |
2676 | distribution. The root of this dependency graph is a small set of | |
2677 | @dfn{bootstrap binaries}, provided by the @code{(gnu packages | |
b81e1947 LC |
2678 | bootstrap)} module. For more information on bootstrapping, |
2679 | @ref{Bootstrapping}. | |
2680 | ||
da7cabd4 AE |
2681 | @node Packaging Guidelines |
2682 | @section Packaging Guidelines | |
b81e1947 LC |
2683 | |
2684 | The GNU distribution is nascent and may well lack some of your favorite | |
2685 | packages. This section describes how you can help make the distribution | |
c8c871d1 | 2686 | grow. @xref{Contributing}, for additional information on how you can |
b81e1947 LC |
2687 | help. |
2688 | ||
b81e1947 LC |
2689 | Free software packages are usually distributed in the form of |
2690 | @dfn{source code tarballs}---typically @file{tar.gz} files that contain | |
2691 | all the source files. Adding a package to the distribution means | |
2692 | essentially two things: adding a @dfn{recipe} that describes how to | |
2693 | build the package, including a list of other packages required to build | |
2694 | it, and adding @dfn{package meta-data} along with that recipe, such as a | |
2695 | description and licensing information. | |
2696 | ||
2697 | In Guix all this information is embodied in @dfn{package definitions}. | |
2698 | Package definitions provide a high-level view of the package. They are | |
2699 | written using the syntax of the Scheme programming language; in fact, | |
2700 | for each package we define a variable bound to the package definition, | |
2701 | and export that variable from a module (@pxref{Package Modules}). | |
2702 | However, in-depth Scheme knowledge is @emph{not} a prerequisite for | |
2703 | creating packages. For more information on package definitions, | |
2704 | @ref{Defining Packages}. | |
2705 | ||
2706 | Once a package definition is in place, stored in a file in the Guix | |
2707 | source tree, it can be tested using the @command{guix build} command | |
2708 | (@pxref{Invoking guix build}). For example, assuming the new package is | |
2709 | called @code{gnew}, you may run this command from the Guix build tree: | |
2710 | ||
2711 | @example | |
2712 | ./pre-inst-env guix build gnew --keep-failed | |
2713 | @end example | |
2714 | ||
2715 | Using @code{--keep-failed} makes it easier to debug build failures since | |
7458bd0a LC |
2716 | it provides access to the failed build tree. Another useful |
2717 | command-line option when debugging is @code{--log-file}, to access the | |
2718 | build log. | |
b81e1947 | 2719 | |
5ff3c4b8 PAR |
2720 | If the package is unknown to the @command{guix} command, it may be that |
2721 | the source file contains a syntax error, or lacks a @code{define-public} | |
2722 | clause to export the package variable. To figure it out, you may load | |
2723 | the module from Guile to get more information about the actual error: | |
2724 | ||
2725 | @example | |
2726 | ./pre-inst-env guile -c '(use-modules (gnu packages gnew))' | |
2727 | @end example | |
2728 | ||
b81e1947 LC |
2729 | Once your package builds correctly, please send us a patch |
2730 | (@pxref{Contributing}). Well, if you need help, we will be happy to | |
2731 | help you too. Once the patch is committed in the Guix repository, the | |
2732 | new package automatically gets built on the supported platforms by | |
2733 | @url{http://hydra.gnu.org/gnu/master, our continuous integration | |
2734 | system}. | |
2735 | ||
2736 | @cindex substituter | |
2737 | Users can obtain the new package definition simply by running | |
2738 | @command{guix pull} (@pxref{Invoking guix pull}). When | |
2739 | @code{hydra.gnu.org} is done building the package, installing the | |
c4202d60 LC |
2740 | package automatically downloads binaries from there |
2741 | (@pxref{Substitutes}). The only place where human intervention is | |
b81e1947 | 2742 | needed is to review and apply the patch. |
401c53c4 LC |
2743 | |
2744 | ||
da7cabd4 | 2745 | @menu |
ee85f3db AE |
2746 | * Software Freedom:: What may go into the distribution. |
2747 | * Package Naming:: What's in a name? | |
2748 | * Version Numbers:: When the name is not enough. | |
2749 | * Python Modules:: Taming the snake. | |
da7cabd4 AE |
2750 | @end menu |
2751 | ||
2752 | @node Software Freedom | |
2753 | @subsection Software Freedom | |
2754 | ||
2755 | @c Adapted from http://www.gnu.org/philosophy/philosophy.html. | |
2756 | ||
2757 | The GNU operating system has been developed so that users can have | |
2758 | freedom in their computing. GNU is @dfn{free software}, meaning that | |
2759 | users have the @url{http://www.gnu.org/philosophy/free-sw.html,four | |
2760 | essential freedoms}: to run the program, to study and change the program | |
2761 | in source code form, to redistribute exact copies, and to distribute | |
2762 | modified versions. Packages found in the GNU distribution provide only | |
2763 | software that conveys these four freedoms. | |
2764 | ||
2765 | In addition, the GNU distribution follow the | |
2766 | @url{http://www.gnu.org/distros/free-system-distribution-guidelines.html,free | |
2767 | software distribution guidelines}. Among other things, these guidelines | |
2768 | reject non-free firmware, recommendations of non-free software, and | |
2769 | discuss ways to deal with trademarks and patents. | |
2770 | ||
f9cc8971 LC |
2771 | Some packages contain a small and optional subset that violates the |
2772 | above guidelines, for instance because this subset is itself non-free | |
2773 | code. When that happens, the offending items are removed with | |
2774 | appropriate patches or code snippets in the package definition's | |
2775 | @code{origin} form (@pxref{Defining Packages}). That way, @code{guix | |
2776 | build --source} returns the ``freed'' source rather than the unmodified | |
2777 | upstream source. | |
2778 | ||
da7cabd4 | 2779 | |
ee85f3db AE |
2780 | @node Package Naming |
2781 | @subsection Package Naming | |
2782 | ||
c8c871d1 | 2783 | A package has actually two names associated with it: |
ee85f3db | 2784 | First, there is the name of the @emph{Scheme variable}, the one following |
c8c871d1 AE |
2785 | @code{define-public}. By this name, the package can be made known in the |
2786 | Scheme code, for instance as input to another package. Second, there is | |
2787 | the string in the @code{name} field of a package definition. This name | |
2788 | is used by package management commands such as | |
2789 | @command{guix package} and @command{guix build}. | |
ee85f3db AE |
2790 | |
2791 | Both are usually the same and correspond to the lowercase conversion of the | |
c8c871d1 AE |
2792 | project name chosen upstream. For instance, the GNUnet project is packaged |
2793 | as @code{gnunet}. We do not add @code{lib} prefixes for library packages, | |
2794 | unless these are already part of the official project name. But see | |
2795 | @ref{Python Modules} for special rules concerning modules for | |
ee85f3db AE |
2796 | the Python language. |
2797 | ||
2798 | ||
2799 | @node Version Numbers | |
2800 | @subsection Version Numbers | |
2801 | ||
2802 | We usually package only the latest version of a given free software | |
c8c871d1 AE |
2803 | project. But sometimes, for instance for incompatible library versions, |
2804 | two (or more) versions of the same package are needed. These require | |
2805 | different Scheme variable names. We use the name as defined | |
2806 | in @ref{Package Naming} | |
ee85f3db AE |
2807 | for the most recent version; previous versions use the same name, suffixed |
2808 | by @code{-} and the smallest prefix of the version number that may | |
2809 | distinguish the two versions. | |
2810 | ||
2811 | The name inside the package definition is the same for all versions of a | |
2812 | package and does not contain any version number. | |
2813 | ||
2814 | For instance, the versions 2.24.20 and 3.9.12 of GTK+ may be packaged as follows: | |
c8c871d1 | 2815 | |
ee85f3db AE |
2816 | @example |
2817 | (define-public gtk+ | |
2818 | (package | |
2819 | (name "gtk+") | |
2820 | (version "3.9.12") | |
2821 | ...)) | |
2822 | (define-public gtk+-2 | |
2823 | (package | |
2824 | (name "gtk+") | |
2825 | (version "2.24.20") | |
2826 | ...)) | |
2827 | @end example | |
2828 | If we also wanted GTK+ 3.8.2, this would be packaged as | |
2829 | @example | |
2830 | (define-public gtk+-3.8 | |
2831 | (package | |
2832 | (name "gtk+") | |
2833 | (version "3.8.2") | |
2834 | ...)) | |
2835 | @end example | |
2836 | ||
2837 | ||
2838 | @node Python Modules | |
2839 | @subsection Python Modules | |
2840 | ||
2841 | We currently package Python 2 and Python 3, under the Scheme variable names | |
2842 | @code{python-2} and @code{python} as explained in @ref{Version Numbers}. | |
2843 | To avoid confusion and naming clashes with other programming languages, it | |
2844 | seems desirable that the name of a package for a Python module contains | |
2845 | the word @code{python}. | |
c8c871d1 | 2846 | |
ee85f3db AE |
2847 | Some modules are compatible with only one version of Python, others with both. |
2848 | If the package Foo compiles only with Python 3, we name it | |
2849 | @code{python-foo}; if it compiles only with Python 2, we name it | |
2850 | @code{python2-foo}. If it is compatible with both versions, we create two | |
2851 | packages with the corresponding names. | |
2852 | ||
2853 | If a project already contains the word @code{python}, we drop this; | |
2854 | for instance, the module python-dateutil is packaged under the names | |
2855 | @code{python-dateutil} and @code{python2-dateutil}. | |
2856 | ||
2857 | ||
2858 | ||
2859 | ||
2860 | ||
401c53c4 LC |
2861 | @node Bootstrapping |
2862 | @section Bootstrapping | |
2863 | ||
2864 | @c Adapted from the ELS 2013 paper. | |
2865 | ||
2866 | @cindex bootstrapping | |
2867 | ||
2868 | Bootstrapping in our context refers to how the distribution gets built | |
2869 | ``from nothing''. Remember that the build environment of a derivation | |
2870 | contains nothing but its declared inputs (@pxref{Introduction}). So | |
2871 | there's an obvious chicken-and-egg problem: how does the first package | |
2872 | get built? How does the first compiler get compiled? Note that this is | |
2873 | a question of interest only to the curious hacker, not to the regular | |
2874 | user, so you can shamelessly skip this section if you consider yourself | |
2875 | a ``regular user''. | |
2876 | ||
2877 | @cindex bootstrap binaries | |
2878 | The GNU system is primarily made of C code, with libc at its core. The | |
2879 | GNU build system itself assumes the availability of a Bourne shell and | |
2880 | command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and | |
2881 | `grep'. Furthermore, build programs---programs that run | |
2882 | @code{./configure}, @code{make}, etc.---are written in Guile Scheme | |
2883 | (@pxref{Derivations}). Consequently, to be able to build anything at | |
2884 | all, from scratch, Guix relies on pre-built binaries of Guile, GCC, | |
2885 | Binutils, libc, and the other packages mentioned above---the | |
2886 | @dfn{bootstrap binaries}. | |
2887 | ||
2888 | These bootstrap binaries are ``taken for granted'', though we can also | |
ba7ea5ce | 2889 | re-create them if needed (more on that later). |
401c53c4 LC |
2890 | |
2891 | @unnumberedsubsec Preparing to Use the Bootstrap Binaries | |
2892 | ||
2893 | @c As of Emacs 24.3, Info-mode displays the image, but since it's a | |
2894 | @c large image, it's hard to scroll. Oh well. | |
29f66ddd | 2895 | @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations} |
401c53c4 LC |
2896 | |
2897 | The figure above shows the very beginning of the dependency graph of the | |
2898 | distribution, corresponding to the package definitions of the @code{(gnu | |
2899 | packages bootstrap)} module. At this level of detail, things are | |
2900 | slightly complex. First, Guile itself consists of an ELF executable, | |
2901 | along with many source and compiled Scheme files that are dynamically | |
2902 | loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz} | |
2903 | tarball shown in this graph. This tarball is part of Guix's ``source'' | |
2904 | distribution, and gets inserted into the store with @code{add-to-store} | |
2905 | (@pxref{The Store}). | |
a1ba8475 | 2906 | |
401c53c4 LC |
2907 | But how do we write a derivation that unpacks this tarball and adds it |
2908 | to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv} | |
2909 | derivation---the first one that gets built---uses @code{bash} as its | |
2910 | builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls | |
2911 | @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar}, | |
2912 | @file{xz}, and @file{mkdir} are statically-linked binaries, also part of | |
2913 | the Guix source distribution, whose sole purpose is to allow the Guile | |
2914 | tarball to be unpacked. | |
2915 | ||
2916 | Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning | |
2917 | Guile that can be used to run subsequent build programs. Its first task | |
2918 | is to download tarballs containing the other pre-built binaries---this | |
2919 | is what the @code{.tar.xz.drv} derivations do. Guix modules such as | |
2920 | @code{ftp-client.scm} are used for this purpose. The | |
2921 | @code{module-import.drv} derivations import those modules in a directory | |
2922 | in the store, using the original layout. The | |
2923 | @code{module-import-compiled.drv} derivations compile those modules, and | |
2924 | write them in an output directory with the right layout. This | |
2925 | corresponds to the @code{#:modules} argument of | |
2926 | @code{build-expression->derivation} (@pxref{Derivations}). | |
2927 | ||
2928 | Finally, the various tarballs are unpacked by the | |
2929 | derivations @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, | |
2930 | etc., at which point we have a working C tool chain. | |
2931 | ||
2932 | ||
2933 | @unnumberedsubsec Building the Build Tools | |
2934 | ||
2935 | @c TODO: Add a package-level dependency graph generated from (gnu | |
2936 | @c packages base). | |
2937 | ||
2938 | Bootstrapping is complete when we have a full tool chain that does not | |
2939 | depend on the pre-built bootstrap tools discussed above. This | |
2940 | no-dependency requirement is verified by checking whether the files of | |
834129e0 | 2941 | the final tool chain contain references to the @file{/gnu/store} |
401c53c4 LC |
2942 | directories of the bootstrap inputs. The process that leads to this |
2943 | ``final'' tool chain is described by the package definitions found in | |
2944 | the @code{(gnu packages base)} module. | |
2945 | ||
2946 | @c See <http://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>. | |
2947 | The first tool that gets built with the bootstrap binaries is | |
2948 | GNU Make, which is a prerequisite for all the following packages. | |
2949 | From there Findutils and Diffutils get built. | |
2950 | ||
2951 | Then come the first-stage Binutils and GCC, built as pseudo cross | |
2952 | tools---i.e., with @code{--target} equal to @code{--host}. They are | |
2953 | used to build libc. Thanks to this cross-build trick, this libc is | |
2954 | guaranteed not to hold any reference to the initial tool chain. | |
2955 | ||
2956 | From there the final Binutils and GCC are built. GCC uses @code{ld} | |
2957 | from the final Binutils, and links programs against the just-built libc. | |
2958 | This tool chain is used to build the other packages used by Guix and by | |
2959 | the GNU Build System: Guile, Bash, Coreutils, etc. | |
2960 | ||
2961 | And voilà! At this point we have the complete set of build tools that | |
2962 | the GNU Build System expects. These are in the @code{%final-inputs} | |
2963 | variables of the @code{(gnu packages base)} module, and are implicitly | |
2964 | used by any package that uses @code{gnu-build-system} (@pxref{Defining | |
2965 | Packages}). | |
2966 | ||
2967 | ||
2968 | @unnumberedsubsec Building the Bootstrap Binaries | |
2969 | ||
2970 | Because the final tool chain does not depend on the bootstrap binaries, | |
2971 | those rarely need to be updated. Nevertheless, it is useful to have an | |
2972 | automated way to produce them, should an update occur, and this is what | |
2973 | the @code{(gnu packages make-bootstrap)} module provides. | |
2974 | ||
2975 | The following command builds the tarballs containing the bootstrap | |
2976 | binaries (Guile, Binutils, GCC, libc, and a tarball containing a mixture | |
2977 | of Coreutils and other basic command-line tools): | |
a1ba8475 | 2978 | |
401c53c4 LC |
2979 | @example |
2980 | guix build bootstrap-tarballs | |
2981 | @end example | |
2982 | ||
2983 | The generated tarballs are those that should be referred to in the | |
2984 | @code{(gnu packages bootstrap)} module mentioned at the beginning of | |
2985 | this section. | |
2986 | ||
2987 | Still here? Then perhaps by now you've started to wonder: when do we | |
2988 | reach a fixed point? That is an interesting question! The answer is | |
2989 | unknown, but if you would like to investigate further (and have | |
2990 | significant computational and storage resources to do so), then let us | |
2991 | know. | |
a1ba8475 | 2992 | |
8b315a6d LC |
2993 | @node Porting |
2994 | @section Porting to a New Platform | |
2995 | ||
2996 | As discussed above, the GNU distribution is self-contained, and | |
2997 | self-containment is achieved by relying on pre-built ``bootstrap | |
2998 | binaries'' (@pxref{Bootstrapping}). These binaries are specific to an | |
2999 | operating system kernel, CPU architecture, and application binary | |
3000 | interface (ABI). Thus, to port the distribution to a platform that is | |
3001 | not yet supported, one must build those bootstrap binaries, and update | |
3002 | the @code{(gnu packages bootstrap)} module to use them on that platform. | |
3003 | ||
3004 | Fortunately, Guix can @emph{cross compile} those bootstrap binaries. | |
3005 | When everything goes well, and assuming the GNU tool chain supports the | |
3006 | target platform, this can be as simple as running a command like this | |
3007 | one: | |
3008 | ||
3009 | @example | |
3010 | guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs | |
3011 | @end example | |
3012 | ||
72e25e35 LC |
3013 | Once these are built, the @code{(gnu packages bootstrap)} module needs |
3014 | to be updated to refer to these binaries on the target platform. In | |
3015 | addition, the @code{glibc-dynamic-linker} procedure in that module must | |
3016 | be augmented to return the right file name for libc's dynamic linker on | |
3017 | that platform; likewise, @code{system->linux-architecture} in @code{(gnu | |
3018 | packages linux)} must be taught about the new platform. | |
3019 | ||
8b315a6d LC |
3020 | In practice, there may be some complications. First, it may be that the |
3021 | extended GNU triplet that specifies an ABI (like the @code{eabi} suffix | |
3022 | above) is not recognized by all the GNU tools. Typically, glibc | |
3023 | recognizes some of these, whereas GCC uses an extra @code{--with-abi} | |
ba7ea5ce | 3024 | configure flag (see @code{gcc.scm} for examples of how to handle this). |
8b315a6d LC |
3025 | Second, some of the required packages could fail to build for that |
3026 | platform. Lastly, the generated binaries could be broken for some | |
3027 | reason. | |
3028 | ||
9bf3c1a7 | 3029 | |
4af2447e LC |
3030 | @node System Configuration |
3031 | @section System Configuration | |
3032 | ||
3033 | @emph{This section documents work-in-progress. As such it may be | |
3034 | incomplete, outdated, or open to discussions. Please discuss it on | |
3035 | @email{guix-devel@@gnu.org}.} | |
3036 | ||
3037 | @cindex system configuration | |
3038 | The GNU system supports a consistent whole-system configuration | |
3039 | mechanism. By that we mean that all aspects of the global system | |
3040 | configuration---such as the available system services, timezone and | |
68ad877c | 3041 | locale settings, user accounts---are declared in a single place. Such |
4af2447e LC |
3042 | a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected. |
3043 | ||
68ad877c LC |
3044 | One of the advantages of putting all the system configuration under the |
3045 | control of Guix is that it supports transactional system upgrades, and | |
3046 | makes it possible to roll-back to a previous system instantiation, | |
3047 | should something go wrong with the new one (@pxref{Features}). Another | |
3048 | one is that it makes it easy to replicate the exact same configuration | |
3049 | across different machines, or at different points in time, without | |
3050 | having to resort to additional administration tools layered on top of | |
3051 | the system's own tools. | |
3052 | @c Yes, we're talking of Puppet, Chef, & co. here. ↑ | |
3053 | ||
4af2447e LC |
3054 | This section describes this mechanism. First we focus on the system |
3055 | administrator's viewpoint---explaining how the system is configured and | |
3056 | instantiated. Then we show how this mechanism can be extended, for | |
3057 | instance to support new system services. | |
3058 | ||
3059 | @menu | |
523e4896 LC |
3060 | * Using the Configuration System:: Customizing your GNU system. |
3061 | * Invoking guix system:: Instantiating a system configuration. | |
3062 | * Defining Services:: Adding new service definitions. | |
4af2447e LC |
3063 | @end menu |
3064 | ||
3065 | @node Using the Configuration System | |
3066 | @subsection Using the Configuration System | |
3067 | ||
3068 | The operating system is configured by filling in an | |
3069 | @code{operating-system} structure, as defined by the @code{(gnu system)} | |
3070 | module. A simple setup, with the default system services, the default | |
3071 | Linux-Libre kernel, initial RAM disk, and boot loader looks like this: | |
3072 | ||
3073 | @findex operating-system | |
3074 | @lisp | |
8b198abe | 3075 | (use-modules (gnu services base) ; for '%base-services' |
db4fdc04 | 3076 | (gnu services ssh) ; for 'lsh-service' |
4af2447e | 3077 | (gnu system shadow) ; for 'user-account' |
4af2447e LC |
3078 | (gnu packages base) ; Coreutils, grep, etc. |
3079 | (gnu packages bash) ; Bash | |
4eaad71d | 3080 | (gnu packages admin) ; dmd, Inetutils |
4af2447e LC |
3081 | (gnu packages zile) ; Zile |
3082 | (gnu packages less) ; less | |
3083 | (gnu packages guile) ; Guile | |
3084 | (gnu packages linux)) ; procps, psmisc | |
3085 | ||
68ad877c | 3086 | (define komputilo |
4af2447e LC |
3087 | (operating-system |
3088 | (host-name "komputilo") | |
3089 | (timezone "Europe/Paris") | |
3090 | (locale "fr_FR.UTF-8") | |
83bcd0b8 LC |
3091 | (file-systems (list (file-system |
3092 | (device "/dev/disk/by-label/root") | |
3093 | (mount-point "/") | |
3094 | (type "ext3")))) | |
4af2447e LC |
3095 | (users (list (user-account |
3096 | (name "alice") | |
3097 | (password "") | |
3098 | (uid 1000) (gid 100) | |
3099 | (comment "Bob's sister") | |
3100 | (home-directory "/home/alice")))) | |
3101 | (packages (list coreutils bash guile-2.0 | |
3102 | guix dmd | |
3103 | inetutils | |
3104 | findutils grep sed | |
3105 | procps psmisc | |
3106 | zile less)) | |
3107 | (services (cons (lsh-service #:port 2222 #:allow-root-login? #t) | |
8b198abe | 3108 | %base-services)))) |
4af2447e LC |
3109 | @end lisp |
3110 | ||
3111 | This example should be self-describing. The @code{packages} field lists | |
68ad877c LC |
3112 | packages provided by the various @code{(gnu packages ...)} modules above |
3113 | (@pxref{Package Modules}). These are the packages that will be globally | |
3114 | visible on the system, for all user accounts---i.e., in every user's | |
3115 | @code{PATH} environment variable---in addition to the per-user profiles | |
3116 | (@pxref{Invoking guix package}). | |
4af2447e | 3117 | |
8b198abe | 3118 | @vindex %base-services |
4af2447e | 3119 | The @code{services} field lists @dfn{system services} to be made |
8b198abe | 3120 | available when the system starts. The @var{%base-services} list, |
db4fdc04 | 3121 | from the @code{(gnu services base)} module, provides the basic services one |
4af2447e LC |
3122 | would expect from a GNU system: a login service (mingetty) on each tty, |
3123 | syslogd, libc's name service cache daemon (nscd), etc. | |
3124 | ||
3125 | The @code{operating-system} declaration above specifies that, in | |
3126 | addition to those services, we want the @command{lshd} secure shell | |
3127 | daemon listening on port 2222, and allowing remote @code{root} logins | |
3128 | (@pxref{Invoking lshd,,, lsh, GNU lsh Manual}). Under the hood, | |
3129 | @code{lsh-service} arranges so that @code{lshd} is started with the | |
3130 | right command-line options, possibly with supporting configuration files | |
3131 | generated as needed (@pxref{Defining Services}). | |
3132 | ||
4af2447e | 3133 | Assuming the above snippet is stored in the @file{my-system-config.scm} |
523e4896 LC |
3134 | file, the @command{guix system boot my-system-config.scm} command |
3135 | instantiates that configuration, and makes it the default GRUB boot | |
3136 | entry (@pxref{Invoking guix system}). The normal way to change the | |
3137 | system's configuration is by updating this file and re-running the | |
3138 | @command{guix system} command. | |
4af2447e LC |
3139 | |
3140 | At the Scheme level, the bulk of an @code{operating-system} declaration | |
3141 | is instantiated with the following monadic procedure (@pxref{The Store | |
3142 | Monad}): | |
3143 | ||
3144 | @deffn {Monadic Procedure} operating-system-derivation os | |
3145 | Return a derivation that builds @var{os}, an @code{operating-system} | |
3146 | object (@pxref{Derivations}). | |
3147 | ||
3148 | The output of the derivation is a single directory that refers to all | |
3149 | the packages, configuration files, and other supporting files needed to | |
3150 | instantiate @var{os}. | |
3151 | @end deffn | |
3152 | ||
523e4896 LC |
3153 | @node Invoking guix system |
3154 | @subsection Invoking @code{guix system} | |
3155 | ||
3156 | Once you have written an operating system declaration, as seen in the | |
3157 | previous section, it can be @dfn{instantiated} using the @command{guix | |
3158 | system} command. The synopsis is: | |
3159 | ||
3160 | @example | |
3161 | guix system @var{options}@dots{} @var{action} @var{file} | |
3162 | @end example | |
3163 | ||
3164 | @var{file} must be the name of a file containing an | |
3165 | @code{operating-system} declaration. @var{action} specifies how the | |
2e7b5cea LC |
3166 | operating system is instantiate. Currently the following values are |
3167 | supported: | |
523e4896 LC |
3168 | |
3169 | @table @code | |
3170 | @item vm | |
3171 | @cindex virtual machine | |
3172 | Build a virtual machine that contain the operating system declared in | |
3173 | @var{file}, and return a script to run that virtual machine (VM). | |
3174 | ||
3175 | The VM shares its store with the host system. | |
2e7b5cea LC |
3176 | |
3177 | @item vm-image | |
3178 | Return a virtual machine image of the operating system declared in | |
3179 | @var{file} that stands alone. Use the @option{--image-size} option to | |
3180 | specify the size of the image. | |
523e4896 LC |
3181 | @end table |
3182 | ||
3183 | @var{options} can contain any of the common build options provided by | |
3184 | @command{guix build} (@pxref{Invoking guix build}). | |
3185 | ||
4af2447e LC |
3186 | |
3187 | @node Defining Services | |
3188 | @subsection Defining Services | |
3189 | ||
db4fdc04 | 3190 | The @code{(gnu services @dots{})} modules define several procedures that allow |
4af2447e LC |
3191 | users to declare the operating system's services (@pxref{Using the |
3192 | Configuration System}). These procedures are @emph{monadic | |
3193 | procedures}---i.e., procedures that return a monadic value in the store | |
3194 | monad (@pxref{The Store Monad}). Examples of such procedures include: | |
3195 | ||
3196 | @table @code | |
3197 | @item mingetty-service | |
3198 | return the definition of a service that runs @command{mingetty} to | |
3199 | offer a login service on the given console tty; | |
3200 | ||
3201 | @item nscd-service | |
3202 | return a definition for libc's name service cache daemon (nscd); | |
3203 | ||
3204 | @item guix-service | |
3205 | return a definition for a service that runs @command{guix-daemon} | |
3206 | (@pxref{Invoking guix-daemon}). | |
3207 | @end table | |
3208 | ||
3209 | @cindex service definition | |
3210 | The monadic value returned by those procedures is a @dfn{service | |
3211 | definition}---a structure as returned by the @code{service} form. | |
3212 | Service definitions specifies the inputs the service depends on, and an | |
3213 | expression to start and stop the service. Behind the scenes, service | |
3214 | definitions are ``translated'' into the form suitable for the | |
3215 | configuration file of dmd, the init system (@pxref{Services,,, dmd, GNU | |
3216 | dmd Manual}). | |
3217 | ||
3218 | As an example, here is what the @code{nscd-service} procedure looks | |
3219 | like: | |
3220 | ||
3221 | @lisp | |
3222 | (define (nscd-service) | |
b5f4e686 | 3223 | (with-monad %store-monad |
4af2447e LC |
3224 | (return (service |
3225 | (documentation "Run libc's name service cache daemon.") | |
3226 | (provision '(nscd)) | |
b5f4e686 LC |
3227 | (start #~(make-forkexec-constructor |
3228 | (string-append #$glibc "/sbin/nscd") | |
3229 | "-f" "/dev/null" "--foreground")) | |
3230 | (stop #~(make-kill-destructor)) | |
3231 | (respawn? #f))))) | |
4af2447e LC |
3232 | @end lisp |
3233 | ||
3234 | @noindent | |
b5f4e686 LC |
3235 | The @code{start} and @code{stop} fields are G-expressions |
3236 | (@pxref{G-Expressions}). They refer to dmd's facilities to start and | |
3237 | stop processes (@pxref{Service De- and Constructors,,, dmd, GNU dmd | |
3238 | Manual}). The @code{provision} field specifies the name under which | |
3239 | this service is known to dmd, and @code{documentation} specifies on-line | |
3240 | documentation. Thus, the commands @command{deco start ncsd}, | |
3241 | @command{deco stop nscd}, and @command{deco doc nscd} will do what you | |
3242 | would expect (@pxref{Invoking deco,,, dmd, GNU dmd Manual}). | |
4af2447e LC |
3243 | |
3244 | ||
9bf3c1a7 LC |
3245 | @c ********************************************************************* |
3246 | @node Contributing | |
3247 | @chapter Contributing | |
3248 | ||
3249 | This project is a cooperative effort, and we need your help to make it | |
5ff3c4b8 PAR |
3250 | grow! Please get in touch with us on @email{guix-devel@@gnu.org} and |
3251 | @code{#guix} on the Freenode IRC network. We welcome ideas, bug | |
3252 | reports, patches, and anything that may be helpful to the project. We | |
3253 | particularly welcome help on packaging (@pxref{Packaging Guidelines}). | |
a1ba8475 | 3254 | |
9bf3c1a7 LC |
3255 | Please see the |
3256 | @url{http://git.savannah.gnu.org/cgit/guix.git/tree/HACKING, | |
3257 | @file{HACKING} file} that comes with the Guix source code for practical | |
3258 | details about contributions. | |
3259 | ||
c78bd12b | 3260 | |
568717fd LC |
3261 | @c ********************************************************************* |
3262 | @node Acknowledgments | |
3263 | @chapter Acknowledgments | |
3264 | ||
3265 | Guix is based on the Nix package manager, which was designed and | |
3266 | implemented by Eelco Dolstra. Nix pioneered functional package | |
3267 | management, and promoted unprecedented features, such as transactional | |
3268 | package upgrades and rollbacks, per-user profiles, and referentially | |
3269 | transparent build processes. Without this work, Guix would not exist. | |
3270 | ||
3271 | The Nix-based software distributions, Nixpkgs and NixOS, have also been | |
3272 | an inspiration for Guix. | |
3273 | ||
3274 | @c ********************************************************************* | |
3275 | @node GNU Free Documentation License | |
3276 | @appendix GNU Free Documentation License | |
3277 | ||
3278 | @include fdl-1.3.texi | |
3279 | ||
3280 | @c ********************************************************************* | |
3281 | @node Concept Index | |
3282 | @unnumbered Concept Index | |
3283 | @printindex cp | |
3284 | ||
3285 | @node Function Index | |
3286 | @unnumbered Function Index | |
3287 | @printindex fn | |
3288 | ||
3289 | @bye | |
3290 | ||
3291 | @c Local Variables: | |
3292 | @c ispell-local-dictionary: "american"; | |
3293 | @c End: |