4.1. Introduction

This chapter includes a list of packages that need to be downloaded for building a basic Linux system. The listed version numbers correspond to versions of the software that are known to work, and this book is based on their use. We highly recommend not using newer versions because the build commands for one version may not work with a newer version. The newest package versions may also have problems that require work-arounds. These work-arounds will be developed and stabilized in the development version of the book.

The packages will be broken up into two groups. The first group of packages are to build the following: toolchain, and a root file system. The second group of packages are the Board Support Packages. These packages will include the Kernel, and may include a bootloader

Download locations may not always be accessible. If a download location has changed since this book was published, Google (http://www.google.com/) provides a useful search engine for most packages. If this search is unsuccessful, try one of the alternative means of downloading discussed at http://cross-lfs.org/files/packages/embedded-0.0.1/.

Downloaded packages and patches will need to be stored somewhere that is conveniently available throughout the entire build. The automated version will look in /usr/src for the packages. If not found it will download to ${CLFS}/usr/src. A working directory is also required to unpack the sources and build them. ${CLFS}/sources can be used both as the place to store the tarballs and patches and as a working directory. By using this directory, the required elements will be located on the CLFS partition and will be available during all stages of the building process.

To create this directory, execute, the following command before starting the download session:

mkdir -v ${CLFS}/sources

Make this directory writable and sticky. When a directory is marked “sticky”, that means that even if multiple users have write permission on that directory, any file within that directory can only be deleted or modified by its owner. The following command will enable the write and sticky modes:

chmod -v a+wt ${CLFS}/sources