| 1 | <?xml version="1.0" encoding="ISO-8859-1"?>
|
|---|
| 2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
|
|---|
| 3 | "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
|
|---|
| 4 | <!ENTITY % general-entities SYSTEM "../../general.ent">
|
|---|
| 5 | %general-entities;
|
|---|
| 6 | ]>
|
|---|
| 7 |
|
|---|
| 8 | <sect1 id="ch-system-introduction">
|
|---|
| 9 | <?dbhtml filename="introduction.html"?>
|
|---|
| 10 |
|
|---|
| 11 | <title>Introduction</title>
|
|---|
| 12 |
|
|---|
| 13 | <para os="a">In this chapter, we enter the building site and start
|
|---|
| 14 | constructing the CLFS system in earnest. The installation of this
|
|---|
| 15 | software is straightforward. Although in many cases the installation
|
|---|
| 16 | instructions could be made shorter and more generic, we have opted
|
|---|
| 17 | to provide the full instructions for every package to minimize the
|
|---|
| 18 | possibilities for mistakes. The key to learning what makes a Linux
|
|---|
| 19 | system work is to know what each package is used for and why the user
|
|---|
| 20 | (or the system) needs it. For every installed package, a summary of
|
|---|
| 21 | its contents is given, followed by concise descriptions of each
|
|---|
| 22 | program and library the package installed.</para>
|
|---|
| 23 |
|
|---|
| 24 | <para os="b">If using compiler optimizations, please review the
|
|---|
| 25 | optimization hint at <ulink url="&hints-root;optimization.txt"/>.
|
|---|
| 26 | Compiler optimizations can make a program run slightly faster, but
|
|---|
| 27 | they may also cause compilation difficulties and problems when
|
|---|
| 28 | running the program. If a package refuses to compile when using
|
|---|
| 29 | optimization, try to compile it without optimization and see if
|
|---|
| 30 | that fixes the problem. Even if the package
|
|---|
| 31 | does compile when using optimization, there is the risk it may have
|
|---|
| 32 | been compiled incorrectly because of the complex interactions between
|
|---|
| 33 | the code and build tools. Also note that the <option>-march</option>
|
|---|
| 34 | and <option>-mtune</option> options may cause problems with the toolchain
|
|---|
| 35 | packages (Binutils, GCC and Glibc). The small potential gains achieved in
|
|---|
| 36 | using compiler optimizations are often outweighed by the risks. First-time
|
|---|
| 37 | builders of CLFS are encouraged to build without custom optimizations.
|
|---|
| 38 | The subsequent system will still run very fast and be stable at the
|
|---|
| 39 | same time.</para>
|
|---|
| 40 |
|
|---|
| 41 | <para os="c">The order that packages are installed in this chapter needs to
|
|---|
| 42 | be strictly followed to ensure that no program accidentally acquires a
|
|---|
| 43 | path referring to <filename class="directory">/tools</filename>
|
|---|
| 44 | hard-wired into it. For the same reason, do not compile packages in
|
|---|
| 45 | parallel. Compiling in parallel may save time (especially on dual-CPU
|
|---|
| 46 | machines), but it could result in a program containing a hard-wired
|
|---|
| 47 | path to <filename class="directory">/tools</filename>, which will
|
|---|
| 48 | cause the program to stop working when that directory is
|
|---|
| 49 | removed.</para>
|
|---|
| 50 |
|
|---|
| 51 | <para os="d">To keep track of which package installs particular files, a
|
|---|
| 52 | package manager can be used. For a general overview of different styles of
|
|---|
| 53 | package managers, please take a look at the next page.</para>
|
|---|
| 54 |
|
|---|
| 55 | </sect1>
|
|---|
