Datasheet

Debian Derivatives

As you will discover later in this book, Debian-derived distributions are based on the Debian Linux dis-

tribution and package management tools such as apt. Debian’s dpkg package management tool was

written around the same time that the original work was done on RPM, although different design deci-

sions and philosophy have seen the two tools continue along separate paths ever since. Debian has a

reputation for forming the basis of a variety of community and commercial Linux distributions.

Debian is a community-maintained Linux distribution, coordinated by a nonprofit organization known

as Software in the Public Interest (SPI). Since the earliest releases, there has been an interest in customiz-

ing Debian and in distributing variants aimed at addressing a particular need. One of the most high-

profile Debian derivatives is the Ubuntu Linux distribution, which aims to encourage widespread

adoption through regulated release cycles and by steering overall development to meet certain goals.

Source Distributions

Linux distributions don’t need to be based upon one of the common package management systems.

There are many alternatives out there that use little or no package management beyond keeping soft-

ware components in separate file archives. In addition, there are distributions that are actually intended

for you to build when they are installed. This can be the case for any number of practical (or ideological)

reasons but such distributions are usually confined to very niche Linux markets.

Build-from-source distributions such as Gentoo are designed to be easy to use but at the same time

deliver high performance through locally customized software for each installed system. Gentoo uses a

system known as portage to automate the process of downloading and building each individual soft-

ware application whenever you require. Just bear in mind that it can take many hours for Open Office to

build the first time you decide you need to use it and instruct portage to build it up for you.

You won’t usually concern yourself with source-based distributions if you’re producing an application

for the mass market. Most customers prefer to use popular commercial or community distributions with

standardized packaging processes. It reduces support headaches and often seems to make life easier. If

you’re interested in Gentoo Linux, don’t forget to visit the project website at

www.gentoo.org.

Roll Your Own

As you’ll discover later in this book, it’s possible to build your own Linux distribution from component

parts. There are any number of reasons that you might want to do this—curiosity, the need for greater

flexibility than is otherwise available, customizability, and so on. The fact is that many of the Embedded

Linux devices on the market today are built entirely from scratch by the vendor producing the device.

Needless to say, we do not encourage you to try building your own Linux distribution before you have

become familiar with the internal packages, software, and utilities required by distributions in general.

The Linux From Scratch project is an example of one self-help guide you can use in building your own

Linux distributions from scratch. Their website is

www.linuxfromscratch.org. You can also check out

automated distribution build tools such as PTXdist at

http://ptxdist.sf.net.

Installing a Linux Distribution

Once you have decided upon which Linux distributions you will be working with, you’ll need to set up

at least one development machine. It’s important to realize that you won’t need to install every single

Chapter 1: Working with Linux

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