[287ea55] | 1 | <?xml version="1.0" encoding="ISO-8859-1"?>
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[b06ca36] | 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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[287ea55] | 4 | <!ENTITY % general-entities SYSTEM "../general.ent">
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| 5 | %general-entities;
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| 6 | ]>
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[b330f4a] | 7 |
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[dc931cb] | 8 | <sect1 id="pre-audience">
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[b330f4a] | 9 | <?dbhtml filename="audience.html"?>
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[287ea55] | 10 |
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[b330f4a] | 11 | <title>Audience</title>
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[81fd230] | 12 |
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[b330f4a] | 13 | <para>There are many reasons why somebody would want to read this book.
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| 14 | The principal reason is to install a Linux system from the source code.
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| 15 | A question many people raise is, <quote>why go through all the hassle of
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| 16 | manually building a Linux system from scratch when you can just download
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| 17 | and install an existing one?</quote> That is a good question and is the
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| 18 | impetus for this section of the book.</para>
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[81fd230] | 19 |
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[b330f4a] | 20 | <para>One important reason for LFS's existence is to help people learn
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| 21 | how a Linux system works from the inside out. Building an LFS system
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| 22 | helps demonstrate what makes Linux tick, and how things work together
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| 23 | and depend on each other. One of the best things that this learning
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| 24 | experience provides is the ability to customize Linux to your own tastes
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| 25 | and needs.</para>
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[81fd230] | 26 |
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[b330f4a] | 27 | <para>A key benefit of LFS is that it allows users to have more control
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| 28 | over the system without relying on someone else's Linux implementation.
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| 29 | With LFS, <emphasis>you</emphasis> are in the driver's seat and dictate
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| 30 | every aspect of the system, such as the directory layout and bootscript
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| 31 | setup. You also dictate where, why, and how programs are installed.</para>
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[81fd230] | 32 |
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[b330f4a] | 33 | <para>Another benefit of LFS is the ability to create a very compact Linux
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| 34 | system. When installing a regular distribution, one is often forced to
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| 35 | include several programs which are probably never used. These programs
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| 36 | waste disk space, or worse, CPU cycles. It is not difficult to build an
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| 37 | LFS system of less than 100 megabytes (MB), which is substantially smaller
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| 38 | than the majority of existing installations. Does this still sound like a
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| 39 | lot of space? A few of us have been working on creating a very small
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| 40 | embedded LFS system. We successfully built a system that was specialized
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| 41 | to run the Apache web server with approximately 8MB of disk space used.
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| 42 | Further stripping could bring this down to 5 MB or less. Try that with a
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| 43 | regular distribution! This is only one of the many benefits of designing
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| 44 | your own Linux implementation.</para>
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[81fd230] | 45 |
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[b330f4a] | 46 | <para>We could compare Linux distributions to a hamburger purchased at a
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| 47 | fast-food restaurant—you have no idea what might be in what you are
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| 48 | eating. LFS, on the other hand, does not give you a hamburger. Rather,
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| 49 | LFS provides the recipe to make the exact hamburger desired. This allows
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| 50 | users to review the recipe, omit unwanted ingredients, and add your own
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| 51 | ingredients to enhance the flavor of the burger. When you are satisfied
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| 52 | with the recipe, move on to preparing it. It can be made to exact
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| 53 | specifications—broil it, bake it, deep-fry it, or barbecue it.</para>
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[81fd230] | 54 |
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[b330f4a] | 55 | <para>Another analogy that we can use is that of comparing LFS with a
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| 56 | finished house. LFS provides the skeletal plan of a house, but it is up
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| 57 | to you to build it. LFS maintains the freedom to adjust plans throughout
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| 58 | the process, customizing it to the user's needs and preferences.</para>
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[81fd230] | 59 |
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[b330f4a] | 60 | <para>An additional advantage of a custom built Linux system is security.
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| 61 | By compiling the entire system from source code, you are empowered to audit
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| 62 | everything and apply all the security patches desired. It is no longer
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| 63 | necessary to wait for somebody else to compile binary packages that fix a
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| 64 | security hole. Unless you examine the patch and implement it yourself, you
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| 65 | have no guarantee that the new binary package was built correctly and
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| 66 | adequately fixes the problem.</para>
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[81fd230] | 67 |
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[b330f4a] | 68 | <para>The goal of Linux From Scratch is to build a complete and usable
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| 69 | foundation-level system. Readers who do not wish to build their own Linux
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| 70 | system from scratch may not benefit from the information in this book. If
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| 71 | you only want to know what happens while the computer boots, we recommend
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| 72 | the <quote>From Power Up To Bash Prompt</quote> HOWTO located at
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| 73 | <ulink url="http://axiom.anu.edu.au/~okeefe/p2b/"/> or on The Linux
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| 74 | Documentation Project's (TLDP) website at <ulink
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| 75 | url="http://www.tldp.org/HOWTO/From-PowerUp-To-Bash-Prompt-HOWTO.html"/>.
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| 76 | The HOWTO builds a system which is similar to that of this book, but it
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| 77 | focuses strictly on creating a system capable of booting to a BASH prompt.
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| 78 | Consider your objective. If you wish to build a Linux system while learning
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| 79 | along the way, then this book is your best choice.</para>
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[e431af69] | 80 |
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[b330f4a] | 81 | <para>There are too many good reasons to build your own LFS system to
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| 82 | list them all here. This section is only the tip of the iceberg. As
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| 83 | you continue in your LFS experience, you will find the power that
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| 84 | information and knowledge truly bring.</para>
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[81fd230] | 85 |
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[b330f4a] | 86 | </sect1>
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