Planet
navi homePPSaboutscreenshotsdownloaddevelopmentforum

source: downloads/boost_1_33_1/doc/html/bbv2/tutorial/hierarchy.html @ 12

Last change on this file since 12 was 12, checked in by landauf, 18 years ago

added boost
File size: 6.4 KB
Line 
1<html>
2<head>
3<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
4<title>Project Hierarchies</title>
5<link rel="stylesheet" href="../../boostbook.css" type="text/css">
6<meta name="generator" content="DocBook XSL Stylesheets V1.69.1">
7<style type="text/css">
8body { background-image: url('http://docbook.sourceforge.net/release/images/draft.png');
9       background-repeat: no-repeat;
10       background-position: top left;
11       /* The following properties make the watermark "fixed" on the page. */
12       /* I think that's just a bit too distracting for the reader... */
13       /* background-attachment: fixed; */
14       /* background-position: center center; */
15     }</style>
16<link rel="start" href="../../index.html" title="The Boost C++ Libraries">
17<link rel="up" href="../tutorial.html" title="Chapter 23. Tutorial">
18<link rel="prev" href="properties.html" title="Properties">
19<link rel="next" href="libs.html" title="Dependent Targets">
20</head>
21<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
22<table cellpadding="2" width="100%">
23<td valign="top"><img alt="boost.png (6897 bytes)" width="277" height="86" src="../../../../boost.png"></td>
24<td align="center"><a href="../../../../index.htm">Home</a></td>
25<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td>
26<td align="center"><a href="../../../../people/people.htm">People</a></td>
27<td align="center"><a href="../../../../more/faq.htm">FAQ</a></td>
28<td align="center"><a href="../../../../more/index.htm">More</a></td>
29</table>
30<hr>
31<div class="spirit-nav">
32<a accesskey="p" href="properties.html"><img src="../../images/prev.png" alt="Prev"></a><a accesskey="u" href="../tutorial.html"><img src="../../images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../images/home.png" alt="Home"></a><a accesskey="n" href="libs.html"><img src="../../images/next.png" alt="Next"></a>
33</div>
34<div class="section" lang="en">
35<div class="titlepage"><div><div><h2 class="title" style="clear: both">
36<a name="bbv2.tutorial.hierarchy"></a>Project Hierarchies</h2></div></div></div>
37<p>So far we've only considered examples with one project
38    (i.e. with one user-written Boost.Jam file,
39    <code class="filename">Jamroot</code>). A typical large codebase would be
40    composed of many projects organized into a tree. The top of the
41    tree is called the <em class="firstterm">project root</em>.  Every
42    subproject is defined by a file called
43    <code class="filename">Jamfile</code> in a descendant directory of the
44    project root.  The parent project of a subproject is defined by
45    the nearest <code class="filename">Jamfile</code> or
46    <code class="filename">Jamroot</code> file in an ancestor directory. For
47    example, in the following directory layout:
48
49</p>
50<pre class="screen">
51top/
52  |
53  +-- Jamroot
54  |
55  +-- app/
56  |    |
57  |    +-- Jamfile
58  |    `-- app.cpp
59  |
60  `-- util/
61       |
62       +-- foo/
63       .    |
64       .    +-- Jamfile
65       .    `-- bar.cpp
66</pre>
67<p>
68
69      the project root is <code class="filename">top/</code>.  Because there is
70      no <code class="filename">Jamfile</code> in
71      <code class="filename">top/util/</code>, the projects in
72      <code class="filename">top/app/</code> and
73      <code class="filename">top/util/foo/</code> are immediate children of the
74      root project.
75
76      </p>
77<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
78<h3 class="title">Note</h3>
79<p>
80          When we refer to a &#8220;Jamfile,&#8221; set in normal
81          type, we mean a file called either
82          <code class="filename">Jamfile</code> or
83          <code class="filename">Jamroot</code>.  When we need to be more
84          specific, the filename will be set as
85          &#8220;<code class="filename">Jamfile</code>&#8221; or
86          &#8220;<code class="filename">Jamroot</code>.&#8221;
87        </p>
88</div>
89<p>
90      Projects inherit all attributes (such as requirements)
91      from their parents.  Inherited requirements are combined with
92      any requirements specified by the sub-project. 
93      For example, if <code class="filename">top/Jamroot</code> has
94
95</p>
96<pre class="programlisting">
97&lt;include&gt;/home/ghost/local
98</pre>
99<p>
100
101      in its requirements, then all of its sub-projects will have it
102      in their requirements, too.  Of course, any project can add
103      include paths to those specified by its parents. <sup>[<a name="id2854392" href="#ftn.id2854392">5</a>]</sup> 
104    More details can be found in
105      <a href="../advanced/jamfiles.html#bbv2.advanced.projects" title="Projects">the section called &#8220;Projects&#8221;</a>.
106    </p>
107<p>
108      Invoking <span><strong class="command">bjam</strong></span> without explicitly specifying
109      any targets on the command-line builds the project rooted in the
110      current directory.  Building a project does not automatically
111      cause its sub-projects to be built unless the parent project's
112      Jamfile explicitly requests it. In our example,
113      <code class="filename">top/Jamroot</code> might contain:
114
115</p>
116<pre class="programlisting">
117build-project app ;
118</pre>
119<p>
120
121      which would cause the project in <code class="filename">top/app/</code>
122      to be built whenever the project in <code class="filename">top/</code> is
123      built. However, targets in <code class="filename">top/util/foo/</code>
124      will be built only if they are needed by targets in
125      <code class="filename">top/</code> or <code class="filename">top/app/</code>.
126    </p>
127<div class="footnotes">
128<br><hr width="100" align="left">
129<div class="footnote"><p><sup>[<a name="ftn.id2854392" href="#id2854392">5</a>] </sup>Many
130      features will be overridden,
131      rather than added-to, in sub-projects.  See <a href="../reference/definitions.html#bbv2.reference.features.attributes" title="Feature Attributes">the section called &#8220;Feature Attributes&#8221;</a> for more
132      information</p></div>
133</div>
134</div>
135<table width="100%"><tr>
136<td align="left"></td>
137<td align="right"><small></small></td>
138</tr></table>
139<hr>
140<div class="spirit-nav">
141<a accesskey="p" href="properties.html"><img src="../../images/prev.png" alt="Prev"></a><a accesskey="u" href="../tutorial.html"><img src="../../images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../images/home.png" alt="Home"></a><a accesskey="n" href="libs.html"><img src="../../images/next.png" alt="Next"></a>
142</div>
143</body>
144</html>
Note: See TracBrowser for help on using the repository browser.