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index f013ee6f45..8ce046a340 100644
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@@ -2,7 +2,7 @@
2 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> 2 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
3 3
4<chapter id="user-manual-intro"> 4<chapter id="user-manual-intro">
5 <title>BitBake User Manual</title> 5 <title>Overview</title>
6 6
7 <section id="intro"> 7 <section id="intro">
8 <title>Introduction</title> 8 <title>Introduction</title>
@@ -63,7 +63,7 @@
63 <itemizedlist> 63 <itemizedlist>
64 <listitem><para>BitBake, a generic task executor</para></listitem> 64 <listitem><para>BitBake, a generic task executor</para></listitem>
65 <listitem><para>OpenEmbedded, a metadata set utilized by 65 <listitem><para>OpenEmbedded, a metadata set utilized by
66 BitBake.</para></listitem> 66 BitBake</para></listitem>
67 </itemizedlist> 67 </itemizedlist>
68 Today, BitBake is the primary basis of the 68 Today, BitBake is the primary basis of the
69 <ulink url="http://www.openembedded.org/">OpenEmbedded</ulink> 69 <ulink url="http://www.openembedded.org/">OpenEmbedded</ulink>
@@ -97,51 +97,50 @@
97 Support running any number of tasks within a given 97 Support running any number of tasks within a given
98 package, including, but not limited to, fetching 98 package, including, but not limited to, fetching
99 upstream sources, unpacking them, patching them, 99 upstream sources, unpacking them, patching them,
100 configuring them, etc. 100 configuring them, and so forth.
101 </para></listitem> 101 </para></listitem>
102 <listitem><para> 102 <listitem><para>
103 Must be Linux distribution agnostic (both build and 103 Be Linux distribution agnostic for both build and
104 target). 104 target systems.
105 </para></listitem> 105 </para></listitem>
106 <listitem><para> 106 <listitem><para>
107 Must be architecture agnostic 107 Be architecture agnostic.
108 </para></listitem> 108 </para></listitem>
109 <listitem><para> 109 <listitem><para>
110 Must support multiple build and target operating systems 110 Support multiple build and target operating systems
111 (including Cygwin, the BSDs, etc). 111 (e.g. Cygwin, the BSDs, and so forth).
112 </para></listitem> 112 </para></listitem>
113 <listitem><para> 113 <listitem><para>
114 Must be able to be self contained, rather than tightly 114 Be self contained, rather than tightly
115 integrated into the build machine's root 115 integrated into the build machine's root
116 filesystem. 116 filesystem.
117 </para></listitem> 117 </para></listitem>
118 <listitem><para> 118 <listitem><para>
119 There must be a way to handle conditional metadata 119 Handle conditional metadata on the target architecture,
120 (on target architecture, operating system, 120 operating system, distribution, and machine.
121 distribution, machine).
122 </para></listitem> 121 </para></listitem>
123 <listitem><para> 122 <listitem><para>
124 It must be easy for the person using the tools to 123 Be easy to use the tools to supply local metadata and packages
125 supply their own local metadata and packages 124 against which to operate.
126 to operate against.
127 </para></listitem> 125 </para></listitem>
128 <listitem><para> 126 <listitem><para>
129 Must make it easy to collaborate between multiple 127 Be easy to use BitBake to collaborate between multiple
130 projects using BitBake for their builds. 128 projects for their builds.
131 </para></listitem> 129 </para></listitem>
132 <listitem><para> 130 <listitem><para>
133 Should provide an inheritance mechanism to share 131 Provide an inheritance mechanism that share
134 common metadata between many packages. 132 common metadata between many packages.
135 </para></listitem> 133 </para></listitem>
136 </itemizedlist> 134 </itemizedlist>
137 Over time it has become apparent that some further requirements 135 Over time it became apparent that some further requirements
138 were necessary: 136 were necessary:
139 <itemizedlist> 137 <itemizedlist>
140 <listitem><para> 138 <listitem><para>
141 Handle variants of a base recipe (native, sdk, multilib). 139 Handle variants of a base recipe (e.g. native, sdk,
140 and multilib).
142 </para></listitem> 141 </para></listitem>
143 <listitem><para> 142 <listitem><para>
144 Able to split metadata into layers and allow layers 143 Split metadata into layers and allow layers
145 to override each other. 144 to override each other.
146 </para></listitem> 145 </para></listitem>
147 <listitem><para> 146 <listitem><para>
@@ -155,7 +154,7 @@
155 with extensions being made to the basic functionality to 154 with extensions being made to the basic functionality to
156 reflect the additional requirements. 155 reflect the additional requirements.
157 Flexibility and power have always been the priorities. 156 Flexibility and power have always been the priorities.
158 It is highly extensible, supporting embedded Python code and 157 BitBake is highly extensible and supports embedded Python code and
159 execution of any arbitrary tasks. 158 execution of any arbitrary tasks.
160 </para> 159 </para>
161 </section> 160 </section>
@@ -169,23 +168,30 @@
169 what tasks are required to run, and executes those tasks. 168 what tasks are required to run, and executes those tasks.
170 Similar to GNU Make, BitBake controls how software is 169 Similar to GNU Make, BitBake controls how software is
171 built. 170 built.
172 GNU Make does this using "makefiles". BitBake uses 171 GNU Make achieves its control through "makefiles".
173 "recipes". 172 BitBake uses "recipes".
173 </para>
174
175 <para>
174 BitBake extends the capabilities of a simple 176 BitBake extends the capabilities of a simple
175 tool like GNU make by allowing for much more complex tasks 177 tool like GNU Make by allowing for much more complex tasks
176 to be completed, such as assembling entire embedded Linux 178 to be completed, such as assembling entire embedded Linux
177 distributions. Several concepts must be understood to be able 179 distributions.
178 to leverage the power of the tool. 180 </para>
181
182 <para>
183 The remainder of this section introduces several concepts
184 that should be understood in order to better leverage
185 the power of BitBake.
179 </para> 186 </para>
180 187
181 <section id='recipes'> 188 <section id='recipes'>
182 <title>Recipes</title> 189 <title>Recipes</title>
183 190
184 <para> 191 <para>
185 A BitBake Recipe, denoted by the file extension 192 BitBake Recipes, which are denoted by the file extension
186 <filename>.bb</filename> is the most 193 <filename>.bb</filename>, are the most basic metadata files.
187 basic metadata file. 194 These recipe files provide BitBake the following:
188 These recipe files tell BitBake the following:
189 <itemizedlist> 195 <itemizedlist>
190 <listitem><para>Descriptive information about the package</para></listitem> 196 <listitem><para>Descriptive information about the package</para></listitem>
191 <listitem><para>The version of the recipe</para></listitem> 197 <listitem><para>The version of the recipe</para></listitem>
@@ -193,19 +199,21 @@
193 <listitem><para>Where the source code resides</para></listitem> 199 <listitem><para>Where the source code resides</para></listitem>
194 <listitem><para>Whether the source code requires any patches</para></listitem> 200 <listitem><para>Whether the source code requires any patches</para></listitem>
195 <listitem><para>How to compile the source code</para></listitem> 201 <listitem><para>How to compile the source code</para></listitem>
196 <listitem><para>Where on the target machine to install the package being compiled</para></listitem> 202 <listitem><para>Where on the target machine to install the
203 package being compiled</para></listitem>
197 </itemizedlist> 204 </itemizedlist>
198 </para> 205 </para>
199 206
200 <para> 207 <para>
201 Within the context of BitBake, or any project utilizing BitBake 208 Within the context of BitBake, or any project utilizing BitBake
202 as it's build system, files with the <filename>.bb</filename> 209 as it's build system, files with the <filename>.bb</filename>
203 extension are referred 210 extension are referred to as recipes.
204 to as recipes. 211 <note>
205 The term "package" is also commonly used to describe recipes. 212 The term "package" is also commonly used to describe recipes.
206 However, since the same word is used to describe packaged 213 However, since the same word is used to describe packaged
207 output from a project, it is best to maintain a single 214 output from a project, it is best to maintain a single
208 descriptive term, "recipes". 215 descriptive term, "recipes".
216 </note>
209 </para> 217 </para>
210 </section> 218 </section>
211 219
@@ -213,18 +221,18 @@
213 <title>Configuration Files</title> 221 <title>Configuration Files</title>
214 222
215 <para> 223 <para>
216 Configuration files, denoted by the 224 Configuration files, which are denoted by the
217 <filename>.conf</filename> extension define 225 <filename>.conf</filename> extension, define
218 various configuration variables that govern the project build 226 various configuration variables that govern the project's build
219 process. 227 process.
220 These files fall into several areas that define 228 These files fall into several areas that define
221 machine configuration options, distribution configuration 229 machine configuration options, distribution configuration
222 options, compiler tuning options, general common 230 options, compiler tuning options, general common
223 configuration options and user configuration options. 231 configuration options, and user configuration options.
224 The main configuration file is the sample 232 The main configuration file is the sample
225 <filename>bitbake.conf</filename> file, 233 <filename>bitbake.conf</filename> file, which is
226 located within the bitbake source tree 234 located within the BitBake source tree
227 <filename>/conf</filename> directory. 235 <filename>conf</filename> directory.
228 </para> 236 </para>
229 </section> 237 </section>
230 238
@@ -232,20 +240,21 @@
232 <title>Classes</title> 240 <title>Classes</title>
233 241
234 <para> 242 <para>
235 Class files, denoted by the 243 Class files, which are denoted by the
236 <filename>.bbclass</filename> extension contain 244 <filename>.bbclass</filename> extension, contain
237 information that is useful to share between metadata files. 245 information that is useful to share between metadata files.
238 The BitBake source tree comes with one class metadata file 246 The BitBake source tree currently comes with one class metadata file
239 currently, called <filename>base.bbclass</filename> and it is 247 called <filename>base.bbclass</filename>.
240 found in the <filename>/classes</filename> directory. 248 You can find this file in the
249 <filename>classes</filename> directory.
241 The <filename>base.bbclass</filename> is special in that any 250 The <filename>base.bbclass</filename> is special in that any
242 new classes that a developer adds to a project is required to 251 new classes that a developer adds to a project are required to
243 inherit it automatically. 252 inherit <filename>base.bbclass</filename> automatically.
244 This class contains definitions for standard basic tasks such 253 This class contains definitions for standard basic tasks such
245 as fetching, unpacking, configuring (empty by default), 254 as fetching, unpacking, configuring (empty by default),
246 compiling (runs any Makefile present), installing (empty by 255 compiling (runs any Makefile present), installing (empty by
247 default) and packaging (empty by default). 256 default) and packaging (empty by default).
248 These classes are often overridden or extended by other classes 257 These tasks are often overridden or extended by other classes
249 added during the project development process. 258 added during the project development process.
250 </para> 259 </para>
251 </section> 260 </section>
@@ -255,82 +264,53 @@
255 <title>Obtaining BitBake</title> 264 <title>Obtaining BitBake</title>
256 265
257 <para> 266 <para>
258 There are several ways to obtain BitBake. 267 You can obtain BitBake several different ways:
259 These include installing using your Linux distribution's 268 <itemizedlist>
260 package management system (not recommended), downloading 269 <listitem><para><emphasis>Installation using your Distribution
261 a snapshot from the BitBake source 270 Package Management System:</emphasis>
262 code repository, or using Git to clone the BitBake source 271 This method is not
263 code repository. 272 recommended because the BitBake version, in most
264 The recommended method for daily BitBake use is to download 273 cases provided by your distribution, is several
265 a stable release from the BitBake source code repository. 274 releases behind a snapshot of the BitBake repository.
266 Using your distribution's version as provided in the package 275 </para></listitem>
267 management system is generally not 276 <listitem><para><emphasis>Taking a snapshot of BitBake:</emphasis>
268 recommended as in most cases, such as with the Ubuntu and 277 Downloading a snapshot of BitBake from the
269 Fedora distributions, the version provided is several releases 278 source code repository is the recommended method
270 behind the repository snapshot version and is missing 279 as you are assured of having the most recent stable
271 important bug fixes and enhancements. Similarly, daily use 280 BitBake release.</para>
272 of the latest clone of the Git repository is not recommended 281 <para>The following example downloads a snapshot of
273 as it can be unstable. 282 BitBake version 1.17.0:
274 However, the Git repository clone will provide the User 283 <literallayout class='monospaced'>
275 with the absolute latest version of BitBake.
276 </para>
277 </section>
278
279 <section id='downloading-a-snapshot-from-the-bitbake-source-tree'>
280 <title>Downloading a Snapshot from the BitBake Source Tree</title>
281
282 <para>
283 The recommended method for obtaining and using BitBake on
284 a daily basis is to download the most
285 recent stable snapshot from the Git source code repository
286 as follows:
287 <literallayout class='monospaced'>
288 $ wget http://git.openembedded.org/bitbake/snapshot/bitbake-1.17.0.tar.gz 284 $ wget http://git.openembedded.org/bitbake/snapshot/bitbake-1.17.0.tar.gz
289 $ tar zxpvf bitbake-1.17.0.tar.gz 285 $ tar zxpvf bitbake-1.17.0.tar.gz
290 </literallayout> 286 </literallayout>
291 After extraction of the tarball using the tar utility, 287 After extraction of the tarball using the tar utility,
292 you will have a directory entitled 288 you have a directory entitled
293 <filename>bitbake-1.17.0</filename>. 289 <filename>bitbake-1.17.0</filename>.
294 </para> 290 </para></listitem>
295 </section> 291 <listitem><para><emphasis>Cloning BitBake:</emphasis>
296 292 Using Git to clone the BitBake source code repository
297 <section id='cloning-the-bitbake-git-repository'> 293 is also a recommended method when you need the absolute latest
298 <title>Cloning the BitBake Git Repository</title> 294 BitBake source.
299 295 Realize that using this method could expose you to areas of
300 <para> 296 BitBake that are under development.</para>
301 To obtain the latest BitBake source code from the 297 <para>Here is an example:
302 BitBake Git repository: 298 <literallayout class='monospaced'>
303 <literallayout class='monospaced'>
304 $ git clone git://git.openembedded.org/bitbake 299 $ git clone git://git.openembedded.org/bitbake
305 </literallayout> 300 </literallayout>
306 This will clone the BitBake Git repository into a 301 This command clones the BitBake Git repository into a
307 directory called <filename>bitbake</filename>. 302 directory called <filename>bitbake</filename>.
308 Alternatively, you can 303 Alternatively, you can
309 designate a directory after the git clone command 304 designate a directory after the
310 if you'd prefer to call the new directory something 305 <filename>git clone</filename> command
311 other than <filename>bitbake</filename>. 306 if you want to call the new directory something
312 For example: 307 other than <filename>bitbake</filename>.
313 <literallayout class='monospaced'> 308 Here is an example that names the directory
309 <filename>bbdev</filename>:
310 <literallayout class='monospaced'>
314 $ git clone git://git.openembedded.org/bitbake bbdev 311 $ git clone git://git.openembedded.org/bitbake bbdev
315 </literallayout> 312 </literallayout></para></listitem>
316 This would clone the Git repository into a local directory 313 </itemizedlist>
317 called <filename>bbdev</filename>.
318 Please note that although this method of obtaining the
319 source code will provide the absolute latest version,
320 it is under active development and may not be as stable
321 as a released snapshot.
322 </para>
323 </section>
324
325 <section id='summary'>
326 <title>Summary</title>
327
328 <para>
329 At this point you should have a general idea of the concepts
330 that BitBake was built on and how the
331 source code is organized.
332 You should have a working version of BitBake installed
333 and understand how to setup your environment.
334 </para> 314 </para>
335 </section> 315 </section>
336</chapter> 316</chapter>