1 | <?xml version="1.0" encoding="ISO-8859-1"?>
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2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
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3 | "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
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4 | <!ENTITY % general-entities SYSTEM "../general.ent">
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5 | %general-entities;
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6 | ]>
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7 |
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8 | <sect1 id="ch-system-introduction">
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9 | <?dbhtml filename="introduction.html"?>
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10 |
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11 | <title>Introduction</title>
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12 |
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13 | <para>In this chapter, we enter the building site and start constructing the
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14 | LFS system in earnest. That is, we chroot into the temporary mini Linux system,
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15 | make a few final preparations, and then begin installing the packages.</para>
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16 |
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17 | <para>The installation of this software is straightforward. Although in many
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18 | cases the installation instructions could be made shorter and more generic,
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19 | we have opted to provide the full instructions for every package to minimize
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20 | the possibilities for mistakes. The key to learning what makes a Linux system
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21 | work is to know what each package is used for and why you (or the system)
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22 | may need it.</para>
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23 |
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24 | <para>We do not recommend using optimizations. They can make
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25 | a program run slightly faster, but they may also cause compilation
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26 | difficulties and problems when running the program. If a package refuses to
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27 | compile when using optimization, try to compile it without optimization and
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28 | see if that fixes the problem. Even if the package does compile when using
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29 | optimization, there is the risk it may have been compiled incorrectly because
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30 | of the complex interactions between the code and build tools. Also note that
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31 | the <option>-march</option> and <option>-mtune</option> options using values
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32 | not specified in the book have not been tested. This may cause problems with
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33 | the toolchain packages (Binutils, GCC and Glibc). The small potential gains
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34 | achieved in using compiler optimizations are often outweighed by the risks.
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35 | First-time builders of LFS are encouraged to build without custom
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36 | optimizations. The subsequent system will still run very fast and be stable
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37 | at the same time.</para>
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38 |
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39 | <para>The order that packages are installed in this chapter needs to be
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40 | strictly followed to ensure that no program accidentally acquires a path
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41 | referring to <filename class="directory">/tools</filename> hard-wired into
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42 | it. For the same reason, do not compile separate packages in parallel.
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43 | Compiling in parallel may save time (especially on dual-CPU machines), but it
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44 | could result in a program containing a hard-wired path to <filename
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45 | class="directory">/tools</filename>, which will cause the program to stop
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46 | working when that directory is removed.</para>
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47 |
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48 | <para>Before the installation instructions, each installation page provides
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49 | information about the package, including a concise description of what it
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50 | contains, approximately how long it will take to build, and how much disk
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51 | space is required during this building process. Following the installation
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52 | instructions, there is a list of programs and libraries (along with brief
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53 | descriptions of these) that the package installs.</para>
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54 |
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55 | <note><para>The SBU values and required disk space includes
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56 | test suite data for all applicable packages in Chapter 6.</para></note>
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57 |
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58 | </sect1>
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