Book Image

Mastering Embedded Linux Programming - Third Edition

By : Frank Vasquez, Chris Simmonds
5 (3)
Book Image

Mastering Embedded Linux Programming - Third Edition

5 (3)
By: Frank Vasquez, Chris Simmonds

Overview of this book

If you’re looking for a book that will demystify embedded Linux, then you’ve come to the right place. Mastering Embedded Linux Programming is a fully comprehensive guide that can serve both as means to learn new things or as a handy reference. The first few chapters of this book will break down the fundamental elements that underpin all embedded Linux projects: the toolchain, the bootloader, the kernel, and the root filesystem. After that, you will learn how to create each of these elements from scratch and automate the process using Buildroot and the Yocto Project. As you progress, the book will show you how to implement an effective storage strategy for flash memory chips and install updates to a device remotely once it’s deployed. You’ll also learn about the key aspects of writing code for embedded Linux, such as how to access hardware from apps, the implications of writing multi-threaded code, and techniques to manage memory in an efficient way. The final chapters demonstrate how to debug your code, whether it resides in apps or in the Linux kernel itself. You’ll also cover the different tracers and profilers that are available for Linux so that you can quickly pinpoint any performance bottlenecks in your system. By the end of this Linux book, you’ll be able to create efficient and secure embedded devices using Linux.
Table of Contents (27 chapters)
1
Section 1: Elements of Embedded Linux
10
Section 2: System Architecture and Design Decisions
18
Section 3: Writing Embedded Applications
22
Section 4: Debugging and Optimizing Performance

Configuring the network

Next, let's look at some basic network configurations so that we can communicate with the outside world. I am assuming that there is an Ethernet interface, eth0, and that we only need a simple IPv4 configuration.

These examples use the network utilities that are part of BusyBox, and they are sufficient for a simple use case, using the old-but-reliable ifup and ifdown programs. You can read the manual pages for both to get the details. The main network configuration is stored in /etc/network/interfaces. You will need to create these directories in the staging directory:

etc/network
etc/network/if-pre-up.d
etc/network/if-up.d
var/run

For a static IP address, /etc/network/interfaces would look like this:

auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
    address 192.168.1.101
    netmask 255.255.255.0
    network 192.168.1.0

For a dynamic IP address allocated using...