doc/html/bbv2/tutorial/prebuilt.html


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Prebuilt targets</title>
<link rel="stylesheet" href="../../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.68.1">
<style type="text/css">
body { background-image: url('http://docbook.sourceforge.net/release/images/draft.png');
       background-repeat: no-repeat;
       background-position: top left;
       /* The following properties make the watermark "fixed" on the page. */
       /* I think that's just a bit too distracting for the reader... */
       /* background-attachment: fixed; */
       /* background-position: center center; */
     }</style>
<link rel="start" href="../../index.html" title="The Boost C++ Libraries">
<link rel="up" href="../tutorial.html" title="Chapter 23. Tutorial">
<link rel="prev" href="conditions.html" title="Conditions and alternatives">
<link rel="next" href="../advanced.html" title="Chapter 24. User documentation">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table cellpadding="2" width="100%">
<td valign="top"><img alt="boost.png (6897 bytes)" width="277" height="86" src="../../../../boost.png"></td>
<td align="center"><a href="../../../../index.htm">Home</a></td>
<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td>
<td align="center"><a href="../../../../people/people.htm">People</a></td>
<td align="center"><a href="../../../../more/faq.htm">FAQ</a></td>
<td align="center"><a href="../../../../more/index.htm">More</a></td>
</table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="conditions.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="../advanced.html"><img src="../../images/next.png" alt="Next"></a>
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="bbv2.tutorial.prebuilt"></a>Prebuilt targets</h2></div></div></div>
<p>
      To link to libraries whose build instructions aren't given in a Jamfile,
      you need to create <code class="computeroutput">lib</code> targets with an appropriate
      <code class="varname">file</code> property.  Target alternatives can be used to
      associate multiple library files with a single conceptual target. For
      example:
</p>
<pre class="programlisting">
# util/lib2/Jamfile
lib lib2
    : 
    : &lt;file&gt;lib2_release.a &lt;variant&gt;release
    ;

lib lib2
    : 
    : &lt;file&gt;lib2_debug.a &lt;variant&gt;debug
    ;
</pre>
<p>

      This example defines two alternatives for <code class="filename">lib2</code>, and
      for each one names a prebuilt file.  Naturally, there are no sources.
      Instead, the <code class="varname">&lt;file&gt;</code> feature is used to specify
      the file name.
    </p>
<p>
      Once a prebuilt target has been declared, it can be used just like any other target:

</p>
<pre class="programlisting">
exe app : app.cpp ../util/lib2//lib2 ;
</pre>
<p>

      As with any target, the alternative selected depends on the
      properties propagated from <code class="filename">lib2</code>'s dependents.
      If we build the the release and debug versions of <code class="filename">app</code> will be linked
      with <code class="filename">lib2_release.a</code> and <code class="filename">lib2_debug.a</code>, respectively.  

    </p>
<p>
      System libraries&#8212;those that are automatically found by
      the toolset by searching through some set of predetermined
      paths&#8212;should be declared almost like regular ones:

</p>
<pre class="programlisting">
lib pythonlib : : &lt;name&gt;python22 ;
</pre>
<p>

      We again don't specify any sources, but give a
      <code class="varname">name</code> that should be passed to the
      compiler. If the gcc toolset were used to link an executable
      target to <code class="filename">pythonlib</code>, <code class="option">-lpython22</code>
      would appear in the command line (other compilers may use
      different options). 
    </p>
<p>
      We can also specify where the toolset should look for the library:

</p>
<pre class="programlisting">
lib pythonlib : : &lt;name&gt;python22 &lt;search&gt;/opt/lib ;
</pre>
<p>

      And, of course, target alternatives can be used in the usual way:

</p>
<pre class="programlisting">
lib pythonlib : : &lt;name&gt;python22 &lt;variant&gt;release ;
lib pythonlib : : &lt;name&gt;python22_d &lt;variant&gt;debug ;
</pre>
<p>A more advanced use of prebuilt targets is described in <a href="../recipies/site-config.html" title="Targets in site-config.jam">the section called &#8220;Targets in site-config.jam&#8221;</a>.    
    </p>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small></small></td>
</tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="conditions.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="../advanced.html"><img src="../../images/next.png" alt="Next"></a>
</div>
</body>
</html>