/[gentoo]/xml/htdocs/doc/en/handbook/hb-working-portage.xml
Gentoo

Contents of /xml/htdocs/doc/en/handbook/hb-working-portage.xml

Parent Directory Parent Directory | Revision Log Revision Log


Revision 1.43 - (show annotations) (download) (as text)
Tue Nov 9 13:01:52 2004 UTC (10 years, 1 month ago) by swift
Branch: MAIN
Changes since 1.42: +5 -1 lines
File MIME type: application/xml
Adding version/date information in pages

1 <?xml version='1.0' encoding='UTF-8'?>
2 <!DOCTYPE sections SYSTEM "/dtd/book.dtd">
3
4 <!-- The content of this document is licensed under the CC-BY-SA license -->
5 <!-- See http://creativecommons.org/licenses/by-sa/2.0 -->
6
7 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/handbook/hb-working-portage.xml,v 1.42 2004/10/24 18:28:09 neysx Exp $ -->
8
9 <sections>
10
11 <version>1.42</version>
12 <date>October 24, 2004</date>
13
14 <section>
15 <title>Welcome to Portage</title>
16 <body>
17
18 <p>
19 Portage is probably Gentoo's most notable innovation in software management.
20 With its high flexibility and enormous amount of features it is frequently seen
21 as the best software management tool available for Linux.
22 </p>
23
24 <p>
25 Portage is completely written in <uri link="http://www.python.org">Python</uri>
26 and <uri link="http://www.gnu.org/software/bash">Bash</uri> and therefore fully
27 visible to the users as both are scripting languages.
28 </p>
29
30 <p>
31 Most users will work with Portage through the <c>emerge</c> tool. This chapter
32 is not meant to duplicate the information available from the emerge man page.
33 For a complete rundown of emerge's options, please consult the man page:
34 </p>
35
36 <pre caption="Reading the emerge man page">
37 $ <i>man emerge</i>
38 </pre>
39
40 </body>
41 </section>
42 <section>
43 <title>The Portage Tree</title>
44 <subsection>
45 <title>Ebuilds</title>
46 <body>
47
48 <p>
49 When we talk about packages, we often mean software titles that are available to
50 the Gentoo users through the Portage tree. The Portage tree is a collection of
51 <e>ebuilds</e>, files that contain all information Portage needs to maintain
52 software (install, search, query, ...). These ebuilds reside in
53 <path>/usr/portage</path> by default.
54 </p>
55
56 <p>
57 Whenever you ask Portage to perform some action regarding software titles, it
58 will use the ebuilds on your system as a base. It is therefore important that
59 you regularly update the ebuilds on your system so Portage knows about new
60 software, security updates, etc.
61 </p>
62
63 </body>
64 </subsection>
65 <subsection>
66 <title>Updating the Portage Tree</title>
67 <body>
68
69 <p>
70 The Portage tree is usually updated with <uri
71 link="http://rsync.gentoo.org">rsync</uri>, a fast incremental file transfer
72 utility. Updating is fairly simple as the <c>emerge</c> command provides a
73 front-end for rsync:
74 </p>
75
76 <pre caption="Updating the Portage tree">
77 # <i>emerge --sync</i>
78 </pre>
79
80 <p>
81 If you are unable to rsync due to firewall restrictions you can still update
82 your Portage tree by using our daily generated Portage tree snapshots. The
83 <c>emerge-webrsync</c> tool automatically fetches and installs the latest
84 snapshot on your system:
85 </p>
86
87 <pre caption="Running emerge-webrsync">
88 # <i>emerge-webrsync</i>
89 </pre>
90
91 </body>
92 </subsection>
93 </section>
94 <section>
95 <title>Maintaining Software</title>
96 <subsection>
97 <title>Searching for Software</title>
98 <body>
99
100 <p>
101 To search through the Portage tree after software titles, you can use
102 <c>emerge</c> built-in search capabilities. By default, <c>emerge search</c>
103 returns the names of packages whose title matches (either fully or partially)
104 the given search term.
105 </p>
106
107 <p>
108 For instance, to search for all packages who have "pdf" in their name:
109 </p>
110
111 <pre caption="Searching for pdf-named packages">
112 $ <i>emerge search pdf</i>
113 </pre>
114
115 <p>
116 If you want to search through the descriptions as well you can use the
117 <c>--searchdesc</c> (or <c>-S</c>) switch:
118 </p>
119
120 <pre caption="Searching for pdf-related packages">
121 $ <i>emerge --searchdesc pdf</i>
122 </pre>
123
124 <p>
125 When you take a look at the output, you'll notice that it gives you a lot of
126 information. The fields are clearly labelled so we won't go further into their
127 meanings:
128 </p>
129
130 <pre caption="Example emerge search output">
131 * net-print/cups-pdf
132 Latest version available: 1.5.2
133 Latest version installed: [ Not Installed ]
134 Size of downloaded files: 15 kB
135 Homepage: http://cip.physik.uni-wuerzburg.de/~vrbehr/cups-pdf/
136 Description: Provides a virtual printer for CUPS to produce PDF files.
137 License: GPL-2
138 </pre>
139
140 </body>
141 </subsection>
142 <subsection>
143 <title>Installing Software</title>
144 <body>
145
146 <p>
147 Once you've found a software title to your liking, you can easily install it
148 with <c>emerge</c>: just add the package name. For instance, to install
149 <c>gnumeric</c>:
150 </p>
151
152 <pre caption="Installing gnumeric">
153 # <i>emerge gnumeric</i>
154 </pre>
155
156 <p>
157 Since many applications depend on each other, any attempt to install a certain
158 software package might result in the installation of several dependencies as
159 well. Don't worry, Portage handles dependencies well. If you want to find out
160 what Portage <e>would</e> install when you ask it to install a certain package,
161 add the <c>--pretend</c> switch. For instance:
162 </p>
163
164 <pre caption="Pretend to install gnumeric">
165 # <i>emerge --pretend gnumeric</i>
166 </pre>
167
168 <p>
169 When you ask Portage to install a package, it will download the necessary source
170 code from the internet (if necessary) and store it by default in
171 <path>/usr/portage/distfiles</path>. After this it will unpack, compile and
172 install the package. If you want Portage to only download the sources without
173 installing them, add the <c>--fetchonly</c> option to the <c>emerge</c> command:
174 </p>
175
176 <pre caption="Download the sourcecode for gnumeric">
177 # <i>emerge --fetchonly gnumeric</i>
178 </pre>
179
180 </body>
181 </subsection>
182 <subsection>
183 <title>Removing Software</title>
184 <body>
185
186 <p>
187 When you want to remove a software package from your system, use <c>emerge
188 unmerge</c>. This will tell Portage to remove all files installed by that
189 package from your system <e>except</e> the configuration files of that
190 application if you have altered those after the installation. Leaving the
191 configuration files allows you to continue working with the package if you ever
192 decide to install it again.
193 </p>
194
195 <p>
196 However, a <brite>big warning</brite> applies: Portage will <e>not</e> check if
197 the package you want to remove is required by another package. It will however
198 warn you when you want to remove an important package that breaks your system
199 if you unmerge it.
200 </p>
201
202 <pre caption="Removing gnumeric from the system">
203 # <i>emerge unmerge gnumeric</i>
204 </pre>
205
206 <p>
207 When you remove a package from your system, the dependencies of that package
208 that were installed automatically when you installed the software are left. To
209 have Portage locate all dependencies that can now be removed, use
210 <c>emerge</c>'s <c>depclean</c> functionality. We will talk about this later on.
211 </p>
212
213 </body>
214 </subsection>
215 <subsection>
216 <title>Updating your System</title>
217 <body>
218
219 <p>
220 To keep your system in perfect shape (and not to mention install the latest
221 security updates) you need to update your system regularly. Since Portage only
222 checks the ebuilds in your Portage tree you first have to update your Portage
223 tree. When your Portage tree is updated, you can update your system with
224 <c>emerge --update world</c>:
225 </p>
226
227 <pre caption="Updating your system">
228 # <i>emerge --update world</i>
229 </pre>
230
231 <p>
232 Portage will then search for newer version of the applications you have
233 installed. However, it will only verify the versions for the applications you
234 have explicitly installed - not the dependencies. If you want to update every
235 single package on your system, add the <c>--deep</c> argument:
236 </p>
237
238 <pre caption="Updating your entire system">
239 # <i>emerge --update --deep world</i>
240 </pre>
241
242 <p>
243 If you have altered any of your <uri link="?part=2&amp;chap=2">USE flags</uri>
244 lately you might want to add <c>--newuse</c> as well. Portage will then verify
245 if the change requires the installation of new packages or recompilation of
246 existing ones:
247 </p>
248
249 <pre caption="Performing a full update">
250 # <i>emerge --update --deep --newuse world</i>
251 </pre>
252
253 </body>
254 </subsection>
255 <subsection>
256 <title>Stub Packages</title>
257 <body>
258
259 <p>
260 Some packages in the Portage tree don't have any real content but are used to
261 install a collection of packages. For instance, the <c>kde</c> package will
262 install a complete KDE environment on your system by pulling in various
263 KDE-related packages as dependencies.
264 </p>
265
266 <p>
267 If you ever want to remove such a package from your system, running <c>emerge
268 unmerge</c> on the package won't have much effect as the dependencies remain on
269 the system.
270 </p>
271
272 <p>
273 Portage has the functionality to remove orphaned dependencies as well, but since
274 the availability of software is dynamically dependent you first need to update
275 your entire system fully, including the new changes you applied when changing
276 USE flags. After this you can run <c>emerge depclean</c> to remove the orphaned
277 dependencies. When this is done, you need to rebuild the applications that were
278 dynamically linked to the now-removed software titles but don't require them
279 anymore.
280 </p>
281
282 <p>
283 All this is handled with the following three commands:
284 </p>
285
286 <pre caption="Removing orphaned dependencies">
287 # <i>emerge --update --deep --newuse world</i>
288 # <i>emerge depclean</i>
289 # <i>revdep-rebuild</i>
290 </pre>
291
292 <p>
293 <c>revdep-rebuild</c> is provided by the <c>gentoolkit</c> package; don't forget
294 to emerge it first:
295 </p>
296
297 <pre caption="Installing the gentoolkit package">
298 # <i>emerge gentoolkit</i>
299 </pre>
300
301 </body>
302 </subsection>
303 </section>
304 <section>
305 <title>When Portage is Complaining...</title>
306 <subsection>
307 <title>About SLOTs, Virtuals, Branches, Architectures and Profiles</title>
308 <body>
309
310 <p>
311 As we stated before, Portage is extremely powerful and supports many features
312 that other software management tools lack. To understand this, we explain a few
313 aspects of Portage without going in too much detail.
314 </p>
315
316 <p>
317 With Portage different versions of a single package can coexist on a system.
318 While other distributions tend to name their package to those versions (like
319 <c>freetype</c> and <c>freetype2</c>) Portage uses a technology called
320 <e>SLOT</e>s. An ebuild declares a certain SLOT for its version. Ebuilds with
321 different SLOTs can coexist on the same system. For instance, the
322 <c>freetype</c> package has ebuilds with <c>SLOT="1"</c> and <c>SLOT="2"</c>.
323 </p>
324
325 <p>
326 There are also packages that provide the same functionality but are implemented
327 differently. For instance, <c>metalogd</c>, <c>sysklogd</c> and <c>syslog-ng</c>
328 are all system loggers. Applications that rely on the availability of "a system
329 logger" cannot depend on, for instance, <c>metalogd</c>, as the other system
330 loggers are as good a choice as any. Portage allows for <e>virtuals</e>: each
331 system logger provides <c>virtual/syslog</c> so that applications can depend on
332 <c>virtual/syslog</c>.
333 </p>
334
335 <p>
336 Software in the Portage tree can reside in different branches. By default your
337 system only accepts packages that Gentoo deems stable. Most new software titles,
338 when committed, are added to the testing branch, meaning more testing needs to
339 be done before it is marked as stable. Although you will see the ebuilds for
340 those software in the Portage tree, Portage will not update them before they are
341 placed in the stable branch.
342 </p>
343
344 <p>
345 Some software is only available for a few architectures. Or the software doesn't
346 work on the other architectures, or it needs more testing, or the developer that
347 committed the software to the Portage tree is unable to verify if the package
348 works on different architectures.
349 </p>
350
351 <p>
352 Each Gentoo installation adheres to a certain <c>profile</c> which contains,
353 amongst other information, the list of packages that are required for a system
354 to function normally.
355 </p>
356
357 </body>
358 </subsection>
359 <subsection id="blocked">
360 <title>Blocked Packages</title>
361 <body>
362
363 <pre caption="Portage warning about blocked packages (with --pretend)">
364 [blocks B ] gnome-base/bonobo-activation (from pkg gnome-base/libbonobo-2.4.0)
365 </pre>
366
367 <pre caption="Portage warning about blocked packages (without --pretend)">
368 !!! Error: the gnome-base/bonobo-activation package conflicts with another package.
369 !!! both can't be installed on the same system together.
370 !!! Please use 'emerge --pretend' to determine blockers.
371 </pre>
372
373 <p>
374 Ebuilds contain specific fields that inform Portage about its dependencies.
375 There are two possible dependencies: build dependencies, declared in
376 <c>DEPEND</c> and run-time dependencies, declared in <c>RDEPEND</c>. When one of
377 these dependencies explicitly marks a package or virtual as being <e>not</e>
378 compatible, it triggers a blockage.
379 </p>
380
381 <p>
382 To fix a blockage, you can choose to not install the package or unmerge the
383 conflicting package first. In the given example, you can opt not to install
384 <c>libbonobo</c> or to remove <c>bonobo-activation</c> first.
385 </p>
386
387 </body>
388 </subsection>
389 <subsection id="masked">
390 <title>Masked Packages</title>
391 <body>
392
393 <pre caption="Portage warning about masked packages">
394 !!! all ebuilds that could satisfy "bootsplash" have been masked.
395 </pre>
396
397 <pre caption="Portage warning about masked packages - reason">
398 !!! possible candidates are:
399
400 - gnome-base/gnome-2.8.0_pre1 (masked by: <i>~x86 keyword</i>)
401 - lm-sensors/lm-sensors-2.8.7 (masked by: <i>-sparc keyword</i>)
402 - sys-libs/glibc-2.3.4.20040808 (masked by: <i>-* keyword</i>)
403 - dev-util/cvsd-1.0.2 (masked by: <i>missing keyword</i>)
404 - media-video/ati-gatos-4.3.0 (masked by: <i>package.mask</i>)
405 - sys-libs/glibc-2.3.2-r11 (masked by: <i>profile</i>)
406 </pre>
407
408 <p>
409 When you want to install a package that isn't available for your system, you
410 will receive this masking error. You should try installing a different
411 application that is available for your system or wait until the package is put
412 available. There is always a reason why a package is masked:
413 </p>
414
415 <ul>
416 <li>
417 <b>~arch keyword</b> means that the application is not tested sufficiently
418 to be put in the stable branch. Wait a few days or weeks and try again.
419 </li>
420 <li>
421 <b>-arch keyword</b> or <b>-* keyword</b> means that the application does
422 not work on your architecture. If you believe the package does work file
423 a bug at our <uri link="http://bugs.gentoo.org">bugzilla</uri> website.
424 </li>
425 <li>
426 <b>missing keyword</b> means that the application has not been tested on
427 your architecture yet. Ask the architecture porting team to test the package
428 or test it for them and report your findings on our <uri
429 link="http://bugs.gentoo.org">bugzilla</uri> website.
430 </li>
431 <li>
432 <b>package.mask</b> means that the package has been found corrupt, unstable
433 or worse and has been deliberately marked as do-not-use.
434 </li>
435 <li>
436 <b>profile</b> means that the package has been found not suitable for your
437 profile. The application might break your system if you installed it or is
438 just not compatible with the profile you use.
439 </li>
440 </ul>
441
442 </body>
443 </subsection>
444 <subsection id="missingdependencies">
445 <title>Missing Dependencies</title>
446 <body>
447
448 <pre caption="Portage warning about missing dependency">
449 emerge: there are no ebuilds to satisfy "&gt;=sys-devel/gcc-4.2-r4".
450
451 !!! Problem with ebuild sys-devel/gcc-3.4.2-r2
452 !!! Possibly a DEPEND/*DEPEND problem.
453 </pre>
454
455 <p>
456 The application you are trying to install depends on another package that is not
457 available for your system. Please check <uri
458 link="http://bugs.gentoo.org">bugzilla</uri> if the issue is known and if not,
459 please report it. Unless you are mixing branches this should not occur and is
460 therefore a bug.
461 </p>
462
463 </body>
464 </subsection>
465 <subsection id="ambiguousebuild">
466 <title>Ambiguous Ebuild Name</title>
467 <body>
468
469 <pre caption="Portage warning about ambiguous ebuild names">
470 !!! The short ebuild name "aterm" is ambiguous. Please specify
471 !!! one of the following fully-qualified ebuild names instead:
472
473 dev-libs/aterm
474 x11-terms/aterm
475 </pre>
476
477 <p>
478 The application you want to install has a name that corresponds with more than
479 one package. You need to supply the category name as well. Portage will inform
480 you of possible matches to choose from.
481 </p>
482
483 </body>
484 </subsection>
485 <subsection id="circulardependencies">
486 <title>Circular Dependencies</title>
487 <body>
488
489 <pre caption="Portage warning about circular dependencies">
490 !!! Error: circular dependencies:
491
492 ebuild / net-print/cups-1.1.15-r2 depends on ebuild / app-text/ghostscript-7.05.3-r1
493 ebuild / app-text/ghostscript-7.05.3-r1 depends on ebuild / net-print/cups-1.1.15-r2
494 </pre>
495
496 <p>
497 Two (or more) packages you want to install depend on each other and can
498 therefore not be installed. This is most likely a bug in the Portage tree.
499 Please resync after a while and try again. You can also check <uri
500 link="http://bugs.gentoo.org">bugzilla</uri> if the issue is known and if not,
501 report it.
502 </p>
503
504 </body>
505 </subsection>
506 <subsection id="fetchfailed">
507 <title>Fetch failed</title>
508 <body>
509
510 <pre caption="Portage warning about fetch failed">
511 !!! Fetch failed for sys-libs/ncurses-5.4-r5, continuing...
512 <comment>(...)</comment>
513 !!! Some fetch errors were encountered. Please see above for details.
514 </pre>
515
516 <p>
517 Portage was unable to download the sources for the given application and will
518 try to continue installing the other applications (if applicable). This failure
519 can be due to a mirror that has not synchronised correctly or because the ebuild
520 points to an incorrect location. The server where the sources reside can also be
521 down for some reason.
522 </p>
523
524 <p>
525 Retry after one hour to see if the issue still persists.
526 </p>
527
528 </body>
529 </subsection>
530 <subsection id="profileprotect">
531 <title>System Profile Protection</title>
532 <body>
533
534 <pre caption="Portage warning about profile-protected package">
535 !!! Trying to unmerge package(s) in system profile. 'sys-apps/portage'
536 !!! This could be damaging to your system.
537 </pre>
538
539 <p>
540 You have asked to remove a package that is part of your system's core packages.
541 It is listed in your profile as required and should therefore not be removed
542 from the system.
543 </p>
544
545 </body>
546 </subsection>
547 </section>
548 </sections>

  ViewVC Help
Powered by ViewVC 1.1.20