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			1523 lines
		
	
	
		
			62 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
| <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
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| 
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| <html>
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| <head>
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|   <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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| 
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|   <title>Boost.Build tutorial</title>
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| 
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|   <link href="website/bootstrap/css/bootstrap.min.css" rel="stylesheet">
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|   <link href="website/index.css" rel="stylesheet">
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| 
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| </head>
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| 
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| <body>
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|   
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|   <div lang="en" class="container">
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| 
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|     <div class="header">
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|       <ul>
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|         <li><a href="index.html">About</a>
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|         <li><a href="doc/html/index.html">Documentation</a>
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|         <li><a href="http://github.com/boostorg/build">GitHub</a>
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|       </ul>
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|       <span><b>Boost.Build Tutorial</b></span>
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|     </div>      
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|     
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|     <hr class="hrhead">
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|     <p>Written by Boris Schäling.</p>
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| 
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|     <div class="toc">
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|       <h3>Table of Contents</h3>
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| 
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|       <ul>
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|         <li><a href="#introduction">1. Introduction</a></li>
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| 
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|         <li><a href="#buildprocess">2. Build process</a></li>
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| 
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|         <li><a href="#basic_tasks">3. Basic tasks</a></li>
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| 
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|         <li><a href="#project_management">4. Project management</a></li>
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| 
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|         <li><a href="#best_practices">5. Best practices</a></li>
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| 
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|         <li><a href="#rule_reference">6. Rule reference</a></li>
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| 
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|         <li><a href="#feature_reference">7. Feature reference</a></li>
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|       </ul>
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|     </div>
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| 
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| 
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|     <hr>
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| 
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|     <h2 id="introduction">Introduction<br><small>Compiler- and
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|       platform-independent build system</small></h2>
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| 
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|     <div>
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| 
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|       <p>Boost.Build is a high-level build system which makes it as easy as
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|       possible to manage C++ projects. The idea is to specify in
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|       configuration files just as much as necessary to build a program. For
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|       example it is not required to tell Boost.Build how to use a certain
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|       compiler. Boost.Build supports many compilers out of the box and knows
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|       how to use them. If you create a configuration file you just need to
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|       tell Boost.Build where to find the source files, what the executable
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|       should be called and which compiler Boost.Build should use. Boost.Build
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|       will then try to find the compiler and automatically build the
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|       program.</p>
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| 
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|       <p>As Boost.Build supports many compilers configuration files never
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|       contain any compiler-specific options. Configuration files are entirely
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|       compiler-independent. Of course it is possible to set options like
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|       whether code should be optimized. However these options are written in
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|       a language only understood by Boost.Build. Once a compiler is picked to
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|       build a program Boost.Build translates options in configuration files
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|       to command line options expected by the selected compiler. This makes
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|       it possible to write configuration files once and build a program on
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|       different platforms with different compilers.</p>
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| 
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|       <p>As nice as it sounds Boost.Build can only be used for C++ and C
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|       projects. Boost.Build doesn't know how to use other compilers like a
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|       Java compiler. Although Boost.Build is extensible it makes more sense
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|       to use a different build system for programs implemented in other
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|       programming languages.</p>
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| 
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|       <p>Boost.Build was created to build and install the <a class="link"
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|       href="http://www.boost.org/" target="_top">Boost C++ libraries</a>
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|       easily with different compilers on different platforms. Although
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|       Boost.Build is part of and shipped with the Boost C++ libraries it can
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|       be used separately for any C++ or C project. It's even possible to
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|       <a class="link" href="http://sourceforge.net/projects/boost/files/"
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|       target="_top">download only Boost.Build</a> in case you don't want to
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|       use the Boost C++ libraries.</p>
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| 
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|       <p>This article is an introduction to help you using Boost.Build for
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|       your own C++ or C projects. It gives you a basic understanding of how
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|       Boost.Build works and how you start using it. After reading the article
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|       you should not only be able to use Boost.Build for your own projects,
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|       it will also be easier to understand the <a class="link" href=
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|       "http://www.boost.org/doc/tools/build/doc/html/index.html" target=
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|       "_top">Boost.Build documentation</a> as you'll know the big
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|       picture.</p>
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|     </div>
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|     <hr>
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| 
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|     <h2 id="buildprocess">Build process<br>
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|       <small>Jamfiles and an interpreter called b2</small>
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|     </h2>
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| 
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|     <div>
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| 
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|       <p>The program you use to build a project managed by Boost.Build is
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|       called <span class="command"><strong>b2</strong></span>. If you
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|       downloaded and built the Boost C++ libraries you have used <span class=
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|       "command"><strong>b2</strong></span> already. <span class=
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|       "command"><strong>b2</strong></span> looks for configuration files,
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|       reads them and builds a project accordingly. It also accepts various
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|       command line options which can be useful for example to show all
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|       commands executed by <span class="command"><strong>b2</strong></span>
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|       to build a project.</p>
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| 
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|       <p>Projects can be large and can consist of many components whose
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|       source code is distributed over many directories. Instead of creating
 | |
|       one big configuration file for the entire project components typically
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|       get their own configuration files. This is no different with
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|       Boost.Build: In a large project there will be many configuration files
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|       which have to be found and interpreted by <span class=
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|       "command"><strong>b2</strong></span>.</p>
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| 
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|       <p>For Boost.Build every directory with a configuration file is a
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|       project: If there is a configuration file in a directory something can
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|       be built. Whether it's a component in a subdirectory or a software
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|       consisting of many components doesn't make a difference for
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|       Boost.Build.</p>
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| 
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|       <p>When <span class="command"><strong>b2</strong></span> is started
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|       it doesn't run a search for configuration files on the entire file
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|       system. It searches for a configuration file in the current working
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|       directory only. If it doesn't find a configuration file it doesn't do
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|       anything. <span class="command"><strong>b2</strong></span> does not
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|       search for configuration files in any other directory if there is no
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|       configuration file in the current working directory.</p>
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| 
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|       <p>The configuration file <span class=
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|       "command"><strong>b2</strong></span> is looking for is called
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|       <code class="filename">Jamfile.jam</code>. Files with the extension
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|       <code class="filename">jam</code> are called Jamfiles. If <span class=
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|       "command"><strong>b2</strong></span> finds a Jamfile in the current
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|       working directory it searches for more Jamfiles in parent directories.
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|       <span class="command"><strong>b2</strong></span> climbs up parent
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|       directories until it finds a configuration file called <code class=
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|       "filename">Jamroot.jam</code>. <code class=
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|       "filename">Jamroot.jam</code> is no different from <code class=
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|       "filename">Jamfile.jam</code>. It only indicates that <span class=
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|       "command"><strong>b2</strong></span> doesn't need to look
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|       further.</p>
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| 
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|       <p>The reason why <span class="command"><strong>b2</strong></span>
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|       looks for Jamfiles in parent directories is that it makes it possible
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|       to group settings. If there are some components which should be built
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|       with similar settings they can be stored in a Jamfile in a parent
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|       directory which will be automatically used if a component in a
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|       subdirectory is built.</p>
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| 
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|       <p>Please note that <span class="command"><strong>b2</strong></span>
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|       must find a file called <code class="filename">Jamroot.jam</code>. It
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|       is an error if no <code class="filename">Jamroot.jam</code> exists. If
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|       <code class="filename">Jamroot.jam</code> is in the current working
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|       directory no other file <code class="filename">Jamfile.jam</code> is
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|       required. If <code class="filename">Jamroot.jam</code> is in a parent
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|       directory a file <code class="filename">Jamfile.jam</code> must exist
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|       in the current working directory - otherwise <span class=
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|       "command"><strong>b2</strong></span> doesn't do anything.</p>
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| 
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|       <p>If you copy <span class="command"><strong>b2</strong></span> to a
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|       directory which contains no Jamfiles and start the program you get an
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|       error message. However <span class=
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|       "command"><strong>b2</strong></span> doesn't complain that it can't
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|       find a Jamfile. It complains about not finding the build system.</p>
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|       <pre class="screen">
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| Unable to load Boost.Build: could not find "boost-build.jam"
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| ---------------------------------------------------------------
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| Attempted search from C:\Users\Boris\Desktop up to the root
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| 
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| Please consult the documentation at 'http://www.boost.org'.
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| </pre>
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| 
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|       <p>The first thing <span class="command"><strong>b2</strong></span>
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|       does is not looking for a Jamfile but loading the build system. But
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|       what exactly is the build system?</p>
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| 
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|       <p><span class="command"><strong>b2</strong></span> is an
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|       interpreter. It doesn't really know how to build anything. What
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|       <span class="command"><strong>b2</strong></span> does is interpreting
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|       Jamfiles. Boost.Build is really implemented in Jamfiles. And they
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|       contain all the logic which makes Boost.Build such a powerful tool. As
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|       <span class="command"><strong>b2</strong></span> only does what it
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|       reads in Jamfiles it needs to know where to find the Jamfiles
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|       Boost.Build is made of.</p>
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| 
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|       <p>When <span class="command"><strong>b2</strong></span> is started
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|       it looks for a file <code class="filename">boost-build.jam</code> in
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|       the current working directory. If it doesn't find the file it searches
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|       all parent directories. This file needs to contain only one line to
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|       tell <span class="command"><strong>b2</strong></span> where to find
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|       the build system.</p>
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|       <pre class="programlisting">
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| boost-build C:/boost_1_57_0/tools/build/src ; 
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| </pre>
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| 
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|       <p>The path after <code class="code">boost-build</code> must refer to a
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|       directory which contains a file called <code class=
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|       "filename">bootstrap.jam</code>. This is the file <span class=
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|       "command"><strong>b2</strong></span> needs to load the build system.
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|       As the Boost C++ libraries ship Boost.Build you can refer to the
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|       subdirectory <code class="filename">tools/build</code> of the root
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|       directory of the Boost C++ libraries. And you can always use a slash as
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|       a path separator - even if you are on Windows.</p>
 | |
| 
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|       <p>Please note that there must be a space between the path and the
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|       semicolon at the end of the line. It is an error if the space is
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|       missing. You'll learn more about the syntax used in Jamfiles later in
 | |
|       this article.</p>
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| 
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|       <p>If <span class="command"><strong>b2</strong></span> finds
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|       <code class="filename">boost-build.jam</code> it uses the path within
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|       the file to load the build system. When the build system is loaded it
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|       also prepares itself to use a certain compiler, linker and maybe other
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|       tools required to build a project. Boost.Build refers to these programs
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|       as a toolset. If no command line option is used to start <span class=
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|       "command"><strong>b2</strong></span> the build system tries to find a
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|       toolset it can use automatically. On Windows for example it searches
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|       for Visual C++. And if it detects that Visual C++ is installed it uses
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|       the toolset msvc.</p>
 | |
|       <pre class="screen">
 | |
| warning: No toolsets are configured.
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| warning: Configuring default toolset "msvc".
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| warning: If the default is wrong, your build may not work correctly.
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| warning: Use the "toolset=xxxxx" option to override our guess.
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| warning: For more configuration options, please consult
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| warning: http://boost.org/boost-build2/doc/html/bbv2/advanced/configuration.html
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| </pre>
 | |
| 
 | |
|       <p>If you start <span class="command"><strong>b2</strong></span>
 | |
|       without specifying which toolset should be used you see a warning.
 | |
|       <span class="command"><strong>b2</strong></span> tells you which
 | |
|       toolset it detected and decided to use. If you want to suppress the
 | |
|       warning you must specify the toolset yourself. For example you tell the
 | |
|       build system to use Visual C++ with <span class="command"><strong>b2
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|       toolset=msvc</strong></span>. If you want GCC to be used you enter
 | |
|       <span class="command"><strong>b2 toolset=gcc</strong></span>.</p>
 | |
| 
 | |
|       <p>As of today there are more than 10 toolsets supported. There is a
 | |
|       good chance that Boost.Build will work with the compiler you use out of
 | |
|       the box.</p>
 | |
| 
 | |
|       <p>Once the build system has been found, loaded and knows which toolset
 | |
|       to use - either because you specified one or the build system detected
 | |
|       one automatically - <span class="command"><strong>b2</strong></span>
 | |
|       looks for a file <code class="filename">Jamfile.jam</code> in the
 | |
|       current working directory. If it doesn't find a Jamfile an error
 | |
|       message is printed.</p>
 | |
|       <pre class="screen">
 | |
| error: error: no Jamfile in current directory found, and no target references specified.
 | |
| </pre>
 | |
| 
 | |
|       <p>If you create an empty file <code class=
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|       "filename">Jamfile.jam</code> and start <span class=
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|       "command"><strong>b2</strong></span> again another error message is
 | |
|       printed.</p>
 | |
|       <pre class="screen">
 | |
| error: Could not find parent for project at '.'
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| error: Did not find Jamfile.jam or Jamroot.jam in any parent directory.
 | |
| </pre>
 | |
| 
 | |
|       <p><span class="command"><strong>b2</strong></span> is ultimately
 | |
|       looking for a Jamfile called <code class="filename">Jamroot.jam</code>.
 | |
|       If it doesn't exist in the current working directory <span class=
 | |
|       "command"><strong>b2</strong></span> expects to find it in a parent
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|       directory.</p>
 | |
| 
 | |
|       <p>If you create an empty file <code class=
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|       "filename">Jamroot.jam</code> and start <span class=
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|       "command"><strong>b2</strong></span> the error message is gone.
 | |
|       Obviously there is nothing done by Boost.Build. But now you know how
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|       <span class="command"><strong>b2</strong></span> proceeds to build a
 | |
|       program and what the minimum Boost.Build configuration looks like.</p>
 | |
| 
 | |
|       <p>Please note that if you work on a small project and you need only
 | |
|       one configuration file you can simply call it <code class=
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|       "filename">Jamroot.jam</code>. You don't need another file called
 | |
|       <code class="filename">Jamfile.jam</code>.</p>
 | |
|     </div>
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|     <hr>
 | |
| 
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|     <h2 id="basic_tasks">Basic tasks<br>
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|       <small>Rules and features</small>
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|     </h2>
 | |
| 
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|     <div class="sect1">
 | |
| 
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|       <p>If you look at Jamfiles the syntax might remind you of configuration
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|       files used by other build systems. Simple Jamfiles can look like plain
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|       old configuration files where for example values seem to be assigned to
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|       keys. What is important to understand though is that Jamfiles are
 | |
|       really script files. There is a programming language used to write
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|       Jamfiles. <span class="command"><strong>b2</strong></span> isn't the
 | |
|       core component of Boost.Build which knows how to build programs. The
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|       logic of Boost.Build is in the Jamfiles which tell <span class=
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|       "command"><strong>b2</strong></span> how to build programs.</p>
 | |
| 
 | |
|       <p>Even though Boost.Build is based on a programming language you don't
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|       need to think of programming when you create Jamfiles. The syntax of
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|       the programming language used by Boost.Build tries to remind you more
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|       of creating plain old configuration files. The idea is to have the best
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|       of two worlds: A powerful and flexible programming language but a
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|       simple syntax you might be familiar with from other build systems.</p>
 | |
| 
 | |
|       <p>This article doesn't introduce you into the programming language
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|       Boost.Build is based on. The programming language is proprietary and
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|       not really a joy to use. It is no competitor to popular scripting
 | |
|       languages like Javascript or Python. The developers of Boost.Build
 | |
|       recognize it and work on another version of Boost.Build based on
 | |
|       Python. However all of this shouldn't matter to developers who plan to
 | |
|       manage their projects with Boost.Build. It helps to understand the
 | |
|       syntax of Jamfiles better once one realizes that there is a programming
 | |
|       language inside Boost.Build. But it's not required to learn the details
 | |
|       of the programming language.</p>
 | |
| 
 | |
|       <p>Let's look at a simple Jamfile which can be used to build an
 | |
|       executable <span class="command"><strong>hello</strong></span> from a
 | |
|       source file <code class="filename">hello.cpp</code>.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp ; 
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| </pre>
 | |
| 
 | |
|       <p>Boost.Build provides a lot of built-in rules and <code class=
 | |
|       "code">exe</code> is one of them. While the documentation of
 | |
|       Boost.Build refers to <code class="code">exe</code> as a rule you know
 | |
|       already that the above Jamfile is actually built using a programming
 | |
|       language. As it turns out rules are simply functions. And the Jamfile
 | |
|       above contains a function call.</p>
 | |
| 
 | |
|       <p>For the majority of tasks which are typically required to build
 | |
|       programs Boost.Build provides predefined rules - or functions if you
 | |
|       like. As with functions in other programming languages it is possible
 | |
|       to pass parameters. In the Jamfile above the function <code class=
 | |
|       "code">exe</code> is called with the two parameters hello and
 | |
|       hello.cpp.</p>
 | |
| 
 | |
|       <p>The programming language Boost.Build is based on knows only one data
 | |
|       type: Everything is a list of strings. A list can be empty or contain
 | |
|       one or more strings. In the Jamfile above the function <code class=
 | |
|       "code">exe</code> is called with two parameters each one a list
 | |
|       containing one string.</p>
 | |
|       <pre class="programlisting">
 | |
| exe "hello" : "hello.cpp" ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>It is possible to use quotes. It's not necessary though as after all
 | |
|       every item in a list has the data type string anyway. Quotes are only
 | |
|       used if parameters contain spaces.</p>
 | |
| 
 | |
|       <p>While there is no special delimiter between a rule and the first
 | |
|       parameter a colon must be used to separate other parameters. It is also
 | |
|       required to end a line with a semicolon just as you are used to from
 | |
|       C++.</p>
 | |
| 
 | |
|       <p>Please note that the programming language of Boost.Build requires
 | |
|       that there is a space around all tokens. For example there must be a
 | |
|       space on the left and on the right of the colon and there must be a
 | |
|       space on the left of the semicolon. Without spaces around tokens
 | |
|       <span class="command"><strong>b2</strong></span> won't be able to
 | |
|       parse Jamfiles correctly.</p>
 | |
| 
 | |
|       <p>If <span class="command"><strong>b2</strong></span> is run in a
 | |
|       directory which contains the Jamfile above and a source file
 | |
|       <code class="filename">hello.cpp</code>, and if the msvc toolset is
 | |
|       used on Windows a subdirectory <code class=
 | |
|       "filename">bin\msvc-9.0\debug</code> is created to build an executable
 | |
|       <code class="filename">hello.exe</code>.</p>
 | |
|       <pre class="screen">
 | |
| ...found 9 targets...
 | |
| ...updating 5 targets...
 | |
| common.mkdir bin
 | |
| common.mkdir bin\msvc-9.0
 | |
| common.mkdir bin\msvc-9.0\debug
 | |
| compile-c-c++ bin\msvc-9.0\debug\hello.obj
 | |
| hello.cpp
 | |
| msvc.link bin\msvc-9.0\debug\hello.exe
 | |
| msvc.manifest bin\msvc-9.0\debug\hello.exe
 | |
| ...updated 5 targets...
 | |
| </pre>
 | |
| 
 | |
|       <p>As you see it takes only one line in a Jamfile to build an
 | |
|       executable from a source file. And if the program is built on Windows
 | |
|       there is even the correct file extension <code class=
 | |
|       "filename">exe</code> appended.</p>
 | |
| 
 | |
|       <p>The main advantage of Boost.Build is that you specify just as much
 | |
|       as necessary for a build system to know how to build a program.
 | |
|       Anything Boost.Build can do automatically is done automatically. You
 | |
|       don't need to detect the platform a program is built on to decide if a
 | |
|       file extension like <code class="filename">exe</code> should be
 | |
|       appended or not. And you don't need to specify how a compiler like
 | |
|       Visual C++ has actually to be invoked to compile source code.</p>
 | |
| 
 | |
|       <p>Boost.Build supports a lot of toolsets out of the box. As a program
 | |
|       can be built using different toolsets Boost.Build uses toolset-specific
 | |
|       directories. This way it is possible to build a program with different
 | |
|       toolsets without a toolset constantly overwriting files produced by
 | |
|       another toolset.</p>
 | |
| 
 | |
|       <p>There are not only toolset-specific directories but also
 | |
|       variant-specific directories. A variant is a debug or release version
 | |
|       of a program. For each variant another directory is used to build a
 | |
|       program - again for the reason not to overwrite files produced by
 | |
|       another variant. By default the debug variant is used. That's why the
 | |
|       subdirectory <code class="filename">bin\msvc-9.0\debug</code> was
 | |
|       created. If you want a release version to be created you can specify
 | |
|       the variant on the command line with <span class="command"><strong>b2
 | |
|       variant=release</strong></span> or, even simpler, <span class="command">
 | |
|       <strong>b2 release </strong></span>.</p>
 | |
|       <pre class="screen">
 | |
| ...found 9 targets...
 | |
| ...updating 5 targets...
 | |
| common.mkdir bin
 | |
| common.mkdir bin\msvc-9.0
 | |
| common.mkdir bin\msvc-9.0\release
 | |
| compile-c-c++ bin\msvc-9.0\release\hello.obj
 | |
| hello.cpp
 | |
| msvc.link bin\msvc-9.0\release\hello.exe
 | |
| msvc.manifest bin\msvc-9.0\release\hello.exe
 | |
| ...updated 5 targets...
 | |
| </pre>
 | |
| 
 | |
|       <p>With the variant set to release the subdirectory <code class=
 | |
|       "filename">bin\msvc-9.0\release</code> is used to create the executable
 | |
|       <code class="filename">hello.exe</code>.</p>
 | |
| 
 | |
|       <p>Choosing a variant is something which is done so often that it's
 | |
|       sufficient to enter <span class="command"><strong>b2
 | |
|       release</strong></span>. Boost.Build figures out that release is meant
 | |
|       to choose the variant.</p>
 | |
| 
 | |
|       <p>If you don't want to specify the variant on the command line but
 | |
|       want to build release versions of <code class=
 | |
|       "filename">hello.exe</code> by default the Jamfile has to be
 | |
|       changed.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp : <variant>release ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The <code class="code">exe</code> rule (or, if you prefer, function)
 | |
|       accepts a few more parameters which are optional. The third parameter
 | |
|       is a list of requirements. You can think of command line options which
 | |
|       are always set and passed to commands run to build an executable.</p>
 | |
| 
 | |
|       <p>In order to force a release version to be built the variant has to
 | |
|       be set to release just as it was done before on the command line. The
 | |
|       syntax to set the variant in a Jamfile is different though.</p>
 | |
| 
 | |
|       <p>Boost.Build defines features which look like XML tags. One of the
 | |
|       features supported by Boost.Build is <code class=
 | |
|       "code"><variant></code>. If a feature should be set to a value it
 | |
|       has to be put next to it - without a space in between. Some features
 | |
|       are free which means they can be set to any value you want.
 | |
|       <code class="code"><variant></code> is a non-free feature as it
 | |
|       can only be set to debug or release. No other value is allowed. If
 | |
|       another value is set <code class="code">b2</code> will report an
 | |
|       error.</p>
 | |
| 
 | |
|       <p>If you run <code class="code">b2 variant=debug</code> and try to
 | |
|       build a debug version of <code class="filename">hello.exe</code> it
 | |
|       won't work as the Jamfile contains the requirement that <code class=
 | |
|       "filename">hello.exe</code> is built as a release version. If you want
 | |
|       to be able to overwrite the feature on the command line you have to
 | |
|       pass the feature as the fourth parameter instead of the third.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp : : <variant>release ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The fourth parameter contains features which are used by default but
 | |
|       which can be overwritten.</p>
 | |
| 
 | |
|       <p>If you want both a debug and a release version of <code class=
 | |
|       "filename">hello.exe</code> to be built by default the <code class=
 | |
|       "code"><variant></code> feature needs to be set twice to debug
 | |
|       and release.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp : : <variant>debug <variant>release ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>It is important that <code class="code"><variant></code> is
 | |
|       set twice in the fourth parameter where default values are specified.
 | |
|       If it was the third parameter where requirements are specified
 | |
|       <span class="command"><strong>b2</strong></span> would report an
 | |
|       error. It is possible to set a feature multiple times in the
 | |
|       requirements but only if values are not mutually exclusive. As a
 | |
|       program can't be a debug and a release version at the same time
 | |
|       <code class="code"><variant></code> must be set in the default
 | |
|       values. Only then Boost.Build understands that two versions of
 | |
|       <code class="filename">hello.exe</code> should be built.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp : <define>WIN32 <define>_WIN32 : <variant>debug <variant>release ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The above Jamfile is an example for setting a feature multiple times
 | |
|       in the requirements. The feature <code class=
 | |
|       "code"><define></code> is used to define preprocessor directives.
 | |
|       It is no problem to define several preprocessor directives. Thus there
 | |
|       are now two versions of <code class="filename">hello.exe</code> built
 | |
|       both with the two directives <code class="code">WIN32</code> and
 | |
|       <code class="code">_WIN32</code> defined.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp : : <variant>debug <variant>release <define>WIN32 <define>_WIN32 ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>If the definitions are moved to the fourth parameter and you run
 | |
|       <span class="command"><strong>b2</strong></span> you get the same two
 | |
|       versions of <code class="filename">hello.exe</code> built with the two
 | |
|       directives <code class="code">WIN32</code> and <code class=
 | |
|       "code">_WIN32</code>. As <code class="code"><define></code> does
 | |
|       not expect mutually exclusive values there is no other set of
 | |
|       executables generated. The only difference between this Jamfile and the
 | |
|       previous one is that directives passed in the fourth parameter are
 | |
|       default values which can be dropped while anything passed as a third
 | |
|       parameter is an immutable requirement.</p>
 | |
| 
 | |
|       <p>Here is another example of a feature whose values are mutually
 | |
|       exclusive.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp : : <variant>debug <variant>release <optimization>speed <optimization>off ; 
 | |
| </pre>
 | |
| 
 | |
|       <p><span class="command"><strong>b2</strong></span> creates four
 | |
|       versions of <code class="filename">hello.exe</code>: A debug version
 | |
|       optimized for speed, a debug version with no optimization, a release
 | |
|       version optimized for speed and a release version with no optimization.
 | |
|       All of these versions are built in seperate directories which are
 | |
|       automatically created.</p>
 | |
| 
 | |
|       <p>So far the only rule used was <code class="code">exe</code>. But of
 | |
|       course Boost.Build provides many more built-in rules. Another important
 | |
|       rule is <code class="code">lib</code>. It is used to build a
 | |
|       library.</p>
 | |
|       <pre class="programlisting">
 | |
| lib world : world.cpp ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The above Jamfile builds a shared library from the source file
 | |
|       <code class="filename">world.cpp</code>. On Windows a file <code class=
 | |
|       "filename">world.dll</code> is created. The usual file extension is
 | |
|       again automatically appended by Boost.Build.</p>
 | |
| 
 | |
|       <p>By default a shared library is built. If you want a static library
 | |
|       to be generated you set the <code class="code"><link></code>
 | |
|       feature to static.</p>
 | |
|       <pre class="programlisting">
 | |
| lib world : world.cpp : <link>static ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>Another useful rule is <code class="code">install</code>. After
 | |
|       executables and libraries have been built this rule can be used to
 | |
|       install them.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp ; 
 | |
| install "C:/Program Files/hello" : hello ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The above Jamfile installs the executable <code class=
 | |
|       "filename">hello.exe</code> to the directory <code class=
 | |
|       "filename">C:\Program Files\hello</code>. The second parameter hello is
 | |
|       a reference to the target hello defined in the first line. Please note
 | |
|       that the path has to be put in quotes as it contains a space.</p>
 | |
| 
 | |
|       <p>Here concepts known from other build systems shine through: Instead
 | |
|       of thinking of function calls every line defines a target. Dependencies
 | |
|       are created by referencing other targets. That's how Boost.Build knows
 | |
|       in what order it should build targets.</p>
 | |
| 
 | |
|       <p>Typically the rule <code class="code">install</code> is written
 | |
|       differently though. Instead of passing the installation directory as
 | |
|       the first parameter a feature <code class=
 | |
|       "code"><location></code> is used to set the installation
 | |
|       directory in the third parameter.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp ; 
 | |
| install install-bin : hello : <location>"C:/Program Files/hello" ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The main reason why it's better to use <code class=
 | |
|       "code"><location></code> is that the first parameter always
 | |
|       defines a target. Other rules might refer to a target. That's why it is
 | |
|       a good idea to use target names which don't have to be changed later.
 | |
|       Imagine a program should be installed to a different directory. It's
 | |
|       easier to change the installation directory if the <code class=
 | |
|       "code"><location></code> feature has been used as no other rules
 | |
|       which might refer to install-bin have to be updated.</p>
 | |
| 
 | |
|       <p>There is another reason why it makes sense to use a feature.
 | |
|       Boost.Build supports conditional properties which make it possible to
 | |
|       use different installation directories depending on the platform a
 | |
|       program is built on.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp ; 
 | |
| install install-bin : hello : <target-os>windows:<location>"C:/Program Files/hello" <target-os>linux:<location>/usr/local/bin ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The feature <code class="code"><target-os></code> is another
 | |
|       feature with mutually exclusive values. It can be set for example to
 | |
|       windows or linux but not to both.</p>
 | |
| 
 | |
|       <p>The feature <code class="code"><location></code> follows
 | |
|       <code class="code"><target-os></code> only delimited by a colon.
 | |
|       Such a construct is called conditional property: Boost.Build selects
 | |
|       the installation directory depending on the operating system.</p>
 | |
| 
 | |
|       <p>Of course conditional properties can also be used with other rules.
 | |
|       It is for example possible to define different preprocessor directives
 | |
|       depending on the variant when building a program or a library.</p>
 | |
| 
 | |
|       <p>Boost.Build provides many more built-in rules. Another useful rule
 | |
|       is <code class="code">glob</code> which makes it possible to use
 | |
|       wildcards. In a big project with many source files it's then not
 | |
|       required to list them all one by one but refer to all of them with
 | |
|       <code class="code">glob</code>.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : [ glob *.cpp ] ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The above Jamfile contains a nested function call: The result of the
 | |
|       rule <code class="code">glob</code> is passed as the second parameter
 | |
|       to <code class="code">exe</code>. Due to requirements of the
 | |
|       programming language Boost.Build is based on brackets must be used for
 | |
|       nested function calls.</p>
 | |
|     </div>
 | |
|     <hr>
 | |
| 
 | |
|     <h2 id="project_management">Project management<br>
 | |
|       <small>Multiple Jamfiles</small>
 | |
|     </h2>
 | |
| 
 | |
|     <div>
 | |
| 
 | |
|       <p>In large projects with many Jamfiles it's necessary to connect
 | |
|       Jamfiles somehow. There is typically a <code class=
 | |
|       "filename">Jamroot.jam</code> file in the project's root directory and
 | |
|       many <code class="filename">Jamfile.jam</code> files in subdirectories.
 | |
|       If <span class="command"><strong>b2</strong></span> is run in the
 | |
|       root directory developers probably expect that the entire project
 | |
|       including all components in subdirectories is built. As <span class=
 | |
|       "command"><strong>b2</strong></span> looks for Jamfiles in parent
 | |
|       directories but not in subdirectories Jamfiles need to refer to
 | |
|       Jamfiles in subdirectories explicitly.</p>
 | |
|       <pre class="programlisting">
 | |
| build-project hello ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>If a Jamfile looks like the sample above it refers to a Jamfile in a
 | |
|       subdirectory <code class="filename">hello</code>. <code class=
 | |
|       "code">build-project</code> is a rule which expects a path as its sole
 | |
|       parameter. The path is then used to lookup a Jamfile.</p>
 | |
|       <pre class="programlisting">
 | |
| build-project hello ; 
 | |
| build-project world ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>If you want several projects to be built you must use <code class=
 | |
|       "code">build-project</code> multiple times.</p>
 | |
| 
 | |
|       <p>Apart from referring to Jamfiles in subdirectories it makes also
 | |
|       sense to group options which should be used when building components in
 | |
|       a project.</p>
 | |
|       <pre class="programlisting">
 | |
| project : default-build release ; 
 | |
| build-project hello ; 
 | |
| build-project world ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The <code class="code">project</code> rule accepts various
 | |
|       parameters to set options for the Jamfile in the current working
 | |
|       directory and in subdirectories.</p>
 | |
| 
 | |
|       <p>While other rules like <code class="code">exe</code> and
 | |
|       <code class="code">lib</code> expect parameters to be passed in a
 | |
|       certain order <code class="code">project</code> uses named arguments.
 | |
|       In the sample above the argument's name is default-build. That's why it
 | |
|       is possible to pass the value release in a very different
 | |
|       parameter.</p>
 | |
|       <pre class="programlisting">
 | |
| project : : : : : : : : : default-build release ; 
 | |
| build-project hello ; 
 | |
| build-project world ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>It doesn't make sense to pass release as the tenth parameter. But it
 | |
|       works as <code class="code">project</code> doesn't care about the
 | |
|       order. As the tenth parameter is called default-build it is
 | |
|       accepted.</p>
 | |
| 
 | |
|       <p><code class="code">project</code> supports only a few named
 | |
|       arguments. Another one is requirements which can be used to set options
 | |
|       which can't be overwritten.</p>
 | |
|       <pre class="programlisting">
 | |
| project : requirements <variant>release ; 
 | |
| build-project hello ; 
 | |
| build-project world ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The Jamfile above builds only release versions. It is not possible
 | |
|       to build a debug version anymore as requirements can not be
 | |
|       overwritten. That's the difference to the named argument called
 | |
|       default-build which was used in the previous sample: It can be
 | |
|       overwritten.</p>
 | |
| 
 | |
|       <p>When <code class="code">build-project</code> is used Boost.Build
 | |
|       assumes that the parameter is a reference to a subdirectory. We had
 | |
|       seen another type of reference before.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp ; 
 | |
| install install-bin : hello : <location>"C:/Program Files/hello" ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>In the above Jamfile the <code class="code">install</code> rule
 | |
|       refers to the target hello defined in the first line.</p>
 | |
| 
 | |
|       <p>In a large project it might be necessary to refer to targets which
 | |
|       are defined in Jamfiles in other directories. It is possible to
 | |
|       concatenate a path to a Jamfile and a target with a double slash.</p>
 | |
|       <pre class="programlisting">
 | |
| install install-bin : subdir//hello : <location>"C:/Program Files/hello" ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>Now the <code class="code">install</code> rule refers to a target
 | |
|       hello in a Jamfile in the subdirectory <code class=
 | |
|       "filename">subdir</code>.</p>
 | |
| 
 | |
|       <p>Let's assume that the executable <span class=
 | |
|       "command"><strong>hello</strong></span> depends on a library in another
 | |
|       directory <code class="filename">world</code>. The library is also
 | |
|       built with Boost.Build using the rule <code class=
 | |
|       "code">lib</code>.</p>
 | |
|       <pre class="programlisting">
 | |
| lib world : world.cpp ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>In the Jamfile to build the executable a reference is required to
 | |
|       the Jamfile of the library. It's not necessary to refer to the target
 | |
|       world directly as all targets in a Jamfile are built by default.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp world : : <variant>debug <variant>release ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The above Jamfile assumes that the library and its Jamfile are in a
 | |
|       subdirectory <code class="filename">world</code>.</p>
 | |
| 
 | |
|       <p>When the executable is built there are two versions generated - a
 | |
|       debug and a release version. The Jamfile of the library however doesn't
 | |
|       set the <code class="code"><variant></code> feature. But
 | |
|       Boost.Build assumes that it should build two versions of the library,
 | |
|       too. The feature <code class="code"><variant></code> is said to
 | |
|       be propagated.</p>
 | |
| 
 | |
|       <p>Propagating features simplify project management as you don't need
 | |
|       to set the same features in various Jamfiles. However it also makes it
 | |
|       a bit more complicated to understand how components are built as it all
 | |
|       depends on what features are propagated. You can assume that
 | |
|       Boost.Build knows what it should do. But of course it doesn't mean that
 | |
|       you easily understand what it does.</p>
 | |
| 
 | |
|       <p>Let's look at another example using the feature <code class=
 | |
|       "code"><define></code>.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp world : <define>WIN32 : <variant>debug <variant>release ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The above Jamfile defines a preprocessor directive <code class=
 | |
|       "code">WIN32</code> for the program <span class=
 | |
|       "command"><strong>hello</strong></span>. But will <code class=
 | |
|       "code">WIN32</code> be defined for the library, too?</p>
 | |
| 
 | |
|       <p>It won't as <code class="code"><define></code> is not a
 | |
|       propagating feature. If you wonder how you should know: The only way to
 | |
|       find out which features are propagated is to lookup the
 | |
|       documentation.</p>
 | |
| 
 | |
|       <p>If you installed the Boost C++ libraries you probably want to link
 | |
|       against some of them. You somehow have to add a dependency to the
 | |
|       respective Boost C++ library to your project's Jamfile. If you didn't
 | |
|       delete the directories you had unzipped the source files of the Boost
 | |
|       C++ libraries to you can refer to a target in a Jamfile in the root
 | |
|       directory.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp world C:/boost_1_39_0//filesystem/ ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>Now <span class="command"><strong>hello</strong></span> also depends
 | |
|       on the Boost.Filesystem library. As the target filesystem is defined in
 | |
|       a Jamfile in the root directory of the Boost C++ libraries the
 | |
|       <code class="code">exe</code> rule can refer to it. Not only will the
 | |
|       appropriate Boost C++ libraries be linked - an include directory is
 | |
|       also passed to the compiler to find the header files. If <code class=
 | |
|       "filename">hello.cpp</code> includes <code class=
 | |
|       "filename">boost/filesystem.hpp</code> the header file will be
 | |
|       found.</p>
 | |
| 
 | |
|       <p>In the above Jamfile the path to the root directory of the Boost C++
 | |
|       libraries is hardcoded. Somehow <span class=
 | |
|       "command"><strong>b2</strong></span> needs to know where to find the
 | |
|       Boost C++ libraries. But it would be better if the path was hardcoded
 | |
|       only once in case several components in a project need to link against
 | |
|       some Boost C++ libraries.</p>
 | |
|       <pre class="programlisting">
 | |
| project : requirements <variant>release ; 
 | |
| use-project /boost : C:/boost_1_39_0 ; 
 | |
| build-project hello ; 
 | |
| build-project world ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The <code class="code">use-project</code> rule is used to define an
 | |
|       alias to a Jamfile in another directory. Jamfiles in subdirectories use
 | |
|       then the alias to refer to a Boost C++ library.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp world /boost//filesystem ; 
 | |
| </pre>
 | |
| 
 | |
|       <p><span class="command"><strong>b2</strong></span> figures out that
 | |
|       <code class="filename">hello.cpp</code> is a source file, <code class=
 | |
|       "filename">world</code> a subdirectory and /boost//filesystem a
 | |
|       reference to a target filesystem in a Jamfile in <code class=
 | |
|       "filename">C:\boost_1_39_0</code>.</p>
 | |
| 
 | |
|       <p>Please note that a reference must start with a slash if it should
 | |
|       refer to a project.</p>
 | |
| 
 | |
|       <p>As libraries can be linked differently it is possible to set
 | |
|       features relevant to the linker.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp world /boost//filesystem/<link>static ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>By default libraries are linked dynamically. If libraries should be
 | |
|       linked statically the feature <code class="code"><link></code>
 | |
|       has to be set to static.</p>
 | |
| 
 | |
|       <p>Features can be appended with a slash. If more than one feature
 | |
|       should be set it is appended with another slash to the previous
 | |
|       feature.</p>
 | |
|       <pre class="programlisting">
 | |
| exe hello : hello.cpp world /boost//filesystem/<link>static/<threading>multi ; 
 | |
| </pre>
 | |
| 
 | |
|       <p><code class="code"><threading></code> is another feature which
 | |
|       can be set to single or multi. If <span class=
 | |
|       "command"><strong>hello</strong></span> should be linked against the
 | |
|       thread-safe version of Boost.Filesystem the feature can be set
 | |
|       accordingly.</p>
 | |
| 
 | |
|       <p>Linking a Boost C++ library by referencing a Jamfile might not
 | |
|       always work. If the Boost C++ libraries were installed differently
 | |
|       because they weren't built from source for example there won't be any
 | |
|       Jamfile to reference.</p>
 | |
|       <pre class="programlisting">
 | |
| lib filesystem : : <name>libboost_filesystem <search>C:/libs ; 
 | |
| exe hello : hello.cpp world filesystem : <include>C:/include ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The <code class="code">lib</code> rule can not only be used to build
 | |
|       a library from source. It also has to be used to refer to an existing
 | |
|       and pre-built library.</p>
 | |
| 
 | |
|       <p>If <code class="code">lib</code> shouldn't build a library from
 | |
|       source the second parameter must be empty. Instead in the third
 | |
|       parameter the features <code class="code"><name></code> and
 | |
|       <code class="code"><search></code> are used to specify the
 | |
|       library's name and a location where Boost.Build will find the
 | |
|       library.</p>
 | |
| 
 | |
|       <p>It is important to specify the library's name in a
 | |
|       platform-independent way. For example for the Jamfile above Boost.Build
 | |
|       will try to find a file <code class=
 | |
|       "filename">libboost_filesystem.lib</code> on Windows. The usual file
 | |
|       extension is again automatically appended.</p>
 | |
| 
 | |
|       <p>If you want to reference a file by specifying its exact name you can
 | |
|       use the <code class="code"><file></code> feature.</p>
 | |
| 
 | |
|       <p>If a system library should be referenced for which you can expect
 | |
|       Boost.Build to know where to find it the feature <code class=
 | |
|       "code"><search></code> can be dropped.</p>
 | |
| 
 | |
|       <p>It is also possible to use the <code class="code">project</code>
 | |
|       rule to make sure all targets in a project are automatically linked
 | |
|       against a library.</p>
 | |
|       <pre class="programlisting">
 | |
| lib filesystem : : <name>libboost_filesystem <search>C:/libs ; 
 | |
| explicit filesystem ; 
 | |
| project : requirements <include>C:/include <library>filesystem ; 
 | |
| lib world : world.cpp ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>A feature called <code class="code"><library></code> must be
 | |
|       used to add a library dependency to a <code class="code">project</code>
 | |
|       rule. <code class="code"><library></code> must refer to a
 | |
|       <code class="code">lib</code> rule which uses the already known
 | |
|       features <code class="code"><name></code> and <code class=
 | |
|       "code"><search></code>.</p>
 | |
| 
 | |
|       <p>It is now very important to make the <code class="code">lib</code>
 | |
|       rule explicit. This is done by using the <code class=
 | |
|       "code">explicit</code> rule. It is important as by default all targets
 | |
|       in a Jamfile are built. As the <code class="code">project</code> rule
 | |
|       defines requirements for all targets in the Jamfile they are also
 | |
|       requirements for the <code class="code">lib</code> rule. Thus the
 | |
|       <code class="code">lib</code> rule refers to itself. If the
 | |
|       <code class="code">lib</code> rule is made explicit though it's not
 | |
|       built and no recursive reference occurs.</p>
 | |
| 
 | |
|       <p>Please note that the order of rules in a Jamfile matters only if a
 | |
|       rule refers to a target: Before a target can be referenced it must have
 | |
|       been defined.</p>
 | |
|     </div>
 | |
|     <hr>
 | |
| 
 | |
|     <h2 id="best_practices">Best practices<br>
 | |
|       <small>How Boost.Build is used by others</small>
 | |
|     </h2>
 | |
| 
 | |
|     <div>      
 | |
| 
 | |
|       <p>As Boost.Build is a high-level build system you benefit most if you
 | |
|       keep Jamfiles platform- and compiler-independent. After all the idea is
 | |
|       to build your C++ or C projects on any platform with any compiler
 | |
|       without being required to modify or maintain several Jamfiles.</p>
 | |
| 
 | |
|       <p>A typical problem you'll run into is that third-party libraries you
 | |
|       want to use will be installed in different directories. If you want to
 | |
|       build your project on Windows and Unix platforms paths also look very
 | |
|       different. Furthermore you might need to link against some system
 | |
|       libraries on a platform but not on another.</p>
 | |
| 
 | |
|       <p>Instead of trying to put paths for various platforms in a project's
 | |
|       Jamfiles it is better to rely on configuration files on every system
 | |
|       for system-specific settings. As it turns out <span class=
 | |
|       "command"><strong>b2</strong></span> does indeed look for two more
 | |
|       configuration files when it starts.</p>
 | |
| 
 | |
|       <p>The file <code class="filename">site-config.jam</code> should be
 | |
|       used to set options for an entire system. As it is machine-dependent
 | |
|       <span class="command"><strong>b2</strong></span> expects to find it
 | |
|       in <code class="filename">C:\Windows</code> on Windows platforms and in
 | |
|       <code class="filename">/etc</code> on Unix systems. As <code class=
 | |
|       "filename">site-config.jam</code> is machine-dependent paths to local
 | |
|       libraries are no problem.</p>
 | |
| 
 | |
|       <p>Users might not be able to create or change <code class=
 | |
|       "filename">site-config.jam</code> though. They would either need to
 | |
|       wait for system administrators to update the file or be forced again to
 | |
|       add system-specific paths to their own Jamfiles. As neither is a good
 | |
|       solution, <span class="command"><strong>b2</strong></span> also looks
 | |
|       for a file <code class="filename">user-config.jam</code> in a user's
 | |
|       home directory. On Windows it is a subdirectory of <code class=
 | |
|       "filename">C:\Users</code>, on Unix a subdirecory of <code class=
 | |
|       "filename">/home</code>. As the file <code class=
 | |
|       "filename">user-config.jam</code> can be maintained by users it is
 | |
|       probably used more often than <code class=
 | |
|       "filename">site-config.jam</code>.</p>
 | |
| 
 | |
|       <p>You use <code class="filename">site-config.jam</code> and
 | |
|       <code class="filename">user-config.jam</code> just like any other
 | |
|       Jamfile. As these configuration files do not belong to a project but to
 | |
|       a machine or a user on a machine they are allowed to contain
 | |
|       machine-specific options. For example they could contain a <code class=
 | |
|       "code">using</code> rule.</p>
 | |
|       <pre class="programlisting">
 | |
| using msvc ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The <code class="code">using</code> rule above tells <span class=
 | |
|       "command"><strong>b2</strong></span> to use the msvc toolset. If you
 | |
|       know that there is only Visual C++ installed on a system it makes sense
 | |
|       to put this line into a configuration file. Then <span class=
 | |
|       "command"><strong>b2</strong></span> doesn't need to guess anymore
 | |
|       which toolset to use and won't omit a warning.</p>
 | |
| 
 | |
|       <p>If you define targets in <code class=
 | |
|       "filename">site-config.jam</code> or <code class=
 | |
|       "filename">user-config.jam</code> and want to refer to these targets in
 | |
|       Jamfiles the <code class="code">project</code> rule must be used to set
 | |
|       a name.</p>
 | |
|       <pre class="programlisting">
 | |
| using msvc ; 
 | |
| project user-config ; 
 | |
| lib xml : : <name>libxml <search>C:/lib : : <include>C:/include ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The <code class="code">lib</code> rule is used to refer to a
 | |
|       pre-built library whose basename is libxml and can be found in
 | |
|       <code class="filename">C:\lib</code>. A program which uses this XML
 | |
|       library probably needs to include header files from this library.
 | |
|       That's why in the usage requirements - this is the fifth parameter -
 | |
|       the feature <code class="code"><include></code> is set to
 | |
|       <code class="filename">C:\include</code>: Whoever uses this rule will
 | |
|       inherit the <code class="code"><include></code> feature.</p>
 | |
| 
 | |
|       <p>As the <code class="code">project</code> rule has been used to set
 | |
|       the name user-config a Jamfile can refer to the XML library via
 | |
|       /user-config//xml.</p>
 | |
|       <pre class="programlisting">
 | |
| exe xmlparser : xmlparser.cpp : <library>/user-config//xml ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>In order to build <span class=
 | |
|       "command"><strong>xmlparser</strong></span> the program must be linked
 | |
|       against the XML library. Even though the location of the library and
 | |
|       its header files might vary the Jamfile does not contain any
 | |
|       system-specific paths. The Jamfile expects to find the target xml in
 | |
|       the project user-config. If this is a configuration file it's no
 | |
|       problem to use system-specific paths as after all configuration files
 | |
|       are bound to a machine or to a user on a machine.</p>
 | |
| 
 | |
|       <p>As Boost.Build has been created to build and install the Boost C++
 | |
|       libraries there is built-in support to use pre-built Boost C++
 | |
|       libraries more easily.</p>
 | |
|       <pre class="programlisting">
 | |
| using msvc ; 
 | |
| project user-config ; 
 | |
| using boost : 1.39 : <include>C:/include/boost-1_39 <library>C:/lib ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>The <code class="code">using</code> rule must be used to refer to a
 | |
|       toolset called boost. This toolset is different from toolsets like msvc
 | |
|       which you've read about so far: It doesn't contain any programs which
 | |
|       will be run later. As support for pre-built Boost C++ libraries has
 | |
|       been implemented in a toolset though it's required to use the
 | |
|       <code class="code">using</code> rule.</p>
 | |
| 
 | |
|       <p>Just as with other libraries the location of the Boost C++ libraries
 | |
|       might vary. Thus it makes sense to put the <code class=
 | |
|       "code">using</code> rule into one of the two configuration files.</p>
 | |
| 
 | |
|       <p>It is possible to pass parameters to the <code class=
 | |
|       "code">using</code> rule: The first one is the version number, the
 | |
|       second a list of options. In the Jamfile above the Boost C++ libraries
 | |
|       1.39 are used which can be found in the directories passed as
 | |
|       options.</p>
 | |
| 
 | |
|       <p>Once the boost toolset is used it is possible to use Boost C++
 | |
|       libraries without defining targets yourself.</p>
 | |
|       <pre class="programlisting">
 | |
| import boost ; 
 | |
| boost.use-project 1.39 ; 
 | |
| exe hello : hello.cpp : <library>/boost//thread ; 
 | |
| </pre>
 | |
| 
 | |
|       <p>If a program uses a Boost C++ library it can refer to targets in a
 | |
|       project called boost. In order to recognize the project boost though
 | |
|       the boost module must be imported and the rule <code class=
 | |
|       "code">boost.use-project</code> used: Importing the boost module makes
 | |
|       the <code class="code">boost.use-project</code> rule available. This
 | |
|       rule expects a version number as its sole argument. As it is possible
 | |
|       to use the <code class="code">using</code> rule to refer to various
 | |
|       versions of the Boost C++ libraries a project can specify which version
 | |
|       it wants to use. In the Jamfile above the program <span class=
 | |
|       "command"><strong>hello</strong></span> uses Boost.Thread from version
 | |
|       1.39.</p>
 | |
|     </div>
 | |
|     <hr>
 | |
| 
 | |
|     <h2 id="rule_reference">Rule reference<br>
 | |
|       <small>Building blocks for Jamfiles</small>
 | |
|     </h2>
 | |
| 
 | |
|     <div>
 | |
| 
 | |
|       <p>If you manage a project with Boost.Build and create Jamfiles you use
 | |
|       rules all the time. Thus you should know which rules exist and how they
 | |
|       are used. The following table gives you an overview about the most
 | |
|       important rules.</p>
 | |
| 
 | |
|       <p>There is a star, plus sign or question mark behind some parameters.
 | |
|       The star means there can be arbitrary many values, the plus sign there
 | |
|       must be at least one value and the question mark there must be zero or
 | |
|       exactly one value.</p>
 | |
| 
 | |
|       <table border="0" cellspacing="0" cellpadding="0" id="id369340">
 | |
|         <caption>
 | |
|           Table 1. Rules
 | |
|         </caption>
 | |
| 
 | |
|         <tbody>
 | |
|           <tr>
 | |
|             <th class="col-md-2">Name</th>
 | |
| 
 | |
|             <th>Parameters</th>
 | |
| 
 | |
|             <th>Description</th>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>alias</td>
 | |
| 
 | |
|             <td>name : sources * : requirements * : default-build * :
 | |
|             usage-requirements *</td>
 | |
| 
 | |
|             <td>Refer to sources or any other targets via a new name.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>build-project</td>
 | |
| 
 | |
|             <td>dir</td>
 | |
| 
 | |
|             <td>Refer to a Jamfile in another directory to build a
 | |
|             project.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>conditional</td>
 | |
| 
 | |
|             <td>condition + : requirements *</td>
 | |
| 
 | |
|             <td>Create conditional requirements without using conditional
 | |
|             properties.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>exe</td>
 | |
| 
 | |
|             <td>name : sources * : requirements * : default-build * :
 | |
|             usage-requirements *</td>
 | |
| 
 | |
|             <td>Build an executable.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>explicit</td>
 | |
| 
 | |
|             <td>target-names *</td>
 | |
| 
 | |
|             <td>Make targets explicit.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>glob</td>
 | |
| 
 | |
|             <td>wildcards + : excludes *</td>
 | |
| 
 | |
|             <td>Reference files in a directory via wildcards.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>glob-tree</td>
 | |
| 
 | |
|             <td>wildcards + : excludes *</td>
 | |
| 
 | |
|             <td>Reference files in a directory and all subdirectories via
 | |
|             wildcards.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>install</td>
 | |
| 
 | |
|             <td>name-and-dir : sources * : requirements * : default-build
 | |
|             *</td>
 | |
| 
 | |
|             <td>Install files to a directory.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>lib</td>
 | |
| 
 | |
|             <td>names + : sources * : requirements * : default-build * :
 | |
|             usage-requirements *</td>
 | |
| 
 | |
|             <td>Build a library.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>project</td>
 | |
| 
 | |
|             <td>id ? : options * : *</td>
 | |
| 
 | |
|             <td>Set project options.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>unit-test</td>
 | |
| 
 | |
|             <td>target : source : properties *</td>
 | |
| 
 | |
|             <td>Build and run an executable.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>use-project</td>
 | |
| 
 | |
|             <td>id : where</td>
 | |
| 
 | |
|             <td>Reference a Jamfile in another directory to use the project
 | |
|             id as a target.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td>using</td>
 | |
| 
 | |
|             <td>toolset-module : *</td>
 | |
| 
 | |
|             <td>Select a toolset.</td>
 | |
|           </tr>
 | |
|         </tbody>
 | |
|       </table>
 | |
| 
 | |
|       <p>Your Boost.Build version might support more rules than listed above.
 | |
|       If you want to find out which rules are supported you should check out
 | |
|       the files in the subdirectory <code class="filename">build</code> of
 | |
|       your Boost.Build installation.</p>
 | |
|     </div>
 | |
|     <hr>
 | |
| 
 | |
|     <h2 id="feature_reference">Feature reference<br>
 | |
|       <small>Configuration options for the build process</small>
 | |
|     </h2>
 | |
| 
 | |
|     <div>
 | |
|       
 | |
|       <p>Features allow you to specify exactly how binaries are built. As
 | |
|       there are many configuration options available the list of features is
 | |
|       pretty long. The following table introduces you to the most important
 | |
|       features.</p>
 | |
| 
 | |
|       <table border="0" cellspacing="0" cellpadding="0" id="id369624">
 | |
|         <caption>
 | |
|           Table 2. Features
 | |
|         </caption>
 | |
| 
 | |
|         <tbody>
 | |
|           <tr>
 | |
|             <th class="col-md-2">Name</th>
 | |
| 
 | |
|             <th>Values</th>
 | |
| 
 | |
|             <th>Description</th>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><address-model></td>
 | |
| 
 | |
|             <td>16, 32, 64, 32_64</td>
 | |
| 
 | |
|             <td>Generate 16-, 32- or 64-bit code.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><architecture></td>
 | |
| 
 | |
|             <td>x86, ia64, sparc, power, mips1, mips2, mips3, mips4, mips32,
 | |
|             mips32r2, mips64, parisc, arm, combined, combined-x86-power</td>
 | |
| 
 | |
|             <td>Set processor family to generate code for.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><c++-template-depth></td>
 | |
| 
 | |
|             <td>1, 2, 3, ...</td>
 | |
| 
 | |
|             <td>Set maximum template depth.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><cflags></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Pass flags to C compiler.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><cxxflags></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Pass flags to C++ compiler</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><debug-symbols></td>
 | |
| 
 | |
|             <td>on, off</td>
 | |
| 
 | |
|             <td>Create debug symbols.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><def-file></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Set path to <code class="filename">def</code> file (specific
 | |
|             to Windows DLLs).</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><define></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Define preprocessor directives.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><embed-manifest></td>
 | |
| 
 | |
|             <td>on, off</td>
 | |
| 
 | |
|             <td>Embed manifest (specific to msvc toolset).</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><host-os></td>
 | |
| 
 | |
|             <td>aix, bsd, cygwin, darwin, freebsd, hpux, iphone, linux,
 | |
|             netbsd, openbsd, osf, qnx, qnxnto, sgi, solaris, unix, unixware,
 | |
|             windows</td>
 | |
| 
 | |
|             <td>Use in conditional properties if features depend on host
 | |
|             operating systems.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><include></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Set include directories.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><inlining></td>
 | |
| 
 | |
|             <td>off, on, full</td>
 | |
| 
 | |
|             <td>Inline functions.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><library></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Link to a library (use in <code class="code">project</code>
 | |
|             rule).</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><link></td>
 | |
| 
 | |
|             <td>shared, static</td>
 | |
| 
 | |
|             <td>Link to shared or static version of a library.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><linkflags></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Pass flags to linker.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><location></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Set directory (use in <code class="code">install</code>
 | |
|             rule).</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><name></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Set basename of a library (use in <code class=
 | |
|             "code">lib</code> rule).</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><optimization></td>
 | |
| 
 | |
|             <td>off, speed, space</td>
 | |
| 
 | |
|             <td>Generate optimized code.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><profiling></td>
 | |
| 
 | |
|             <td>off, on</td>
 | |
| 
 | |
|             <td>Generate profiled code.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><runtime-link></td>
 | |
| 
 | |
|             <td>shared, static</td>
 | |
| 
 | |
|             <td>Link to single-threaded or thread-safe runtime library.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><search></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Set directory to search for libraries (use in <code class=
 | |
|             "code">lib</code> rule together with <code class=
 | |
|             "code"><name></code>).</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><source></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Set source in requirements parameter of <code class=
 | |
|             "code">project</code> rule or in conditional properties.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><target-os></td>
 | |
| 
 | |
|             <td>aix, appletv, bsd, cygwin, darwin, freebsd, hpux, iphone, linux,
 | |
|             netbsd, openbsd, osf, qnx, qnxnto, sgi, solaris, unix, unixware,
 | |
|             windows</td>
 | |
| 
 | |
|             <td>Use in conditional properties if features depend on target
 | |
|             operating systems.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><threading></td>
 | |
| 
 | |
|             <td>single, multi</td>
 | |
| 
 | |
|             <td>Build singlethreaded or thread-safe version.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><toolset></td>
 | |
| 
 | |
|             <td>gcc, msvc, intel-linux, intel-win, acc, borland, como-linux,
 | |
|             cw, dmc, hp_cxx, sun</td>
 | |
| 
 | |
|             <td>Use in conditional properties if features depend on
 | |
|             toolsets.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><undef></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Undefine preprocessor directives.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><use></td>
 | |
| 
 | |
|             <td>...</td>
 | |
| 
 | |
|             <td>Take over only usage requirements of a referenced target but
 | |
|             don't do anything else.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><variant></td>
 | |
| 
 | |
|             <td>debug, release, profile</td>
 | |
| 
 | |
|             <td>Build debug, release or profile version.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><warnings></td>
 | |
| 
 | |
|             <td>on, all, off</td>
 | |
| 
 | |
|             <td>Switch off warnings.</td>
 | |
|           </tr>
 | |
| 
 | |
|           <tr>
 | |
|             <td><warnings-as-errors></td>
 | |
| 
 | |
|             <td>off, on</td>
 | |
| 
 | |
|             <td>Treat warnings as errors.</td>
 | |
|           </tr>
 | |
|         </tbody>
 | |
|       </table>
 | |
| 
 | |
|       <p>For a complete and up-to-date reference of Boost.Build features look
 | |
|       up the file <code class="filename">builtin.jam</code> in the
 | |
|       subdirectory <code class="filename">tools</code> of your Boost.Build
 | |
|       installation. Search for lines starting with <code class=
 | |
|       "code">feature.feature</code> - this is the internal rule used to
 | |
|       define features.</p>
 | |
|     </div>
 | |
| 
 | |
|     <hr id="hrfoot">
 | |
|     <p>Copyright Boris Schäling 2009. Distributed under the Boost Software
 | |
|       License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
 | |
|       <a href="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)
 | |
| 
 | |
|   </div>
 | |
| 
 | |
| 
 | |
| </body>
 | |
| </html>
 |