Book Image

Embedded Linux Development Using Yocto Project Cookbook - Second Edition

By : Alex Gonzalez
Book Image

Embedded Linux Development Using Yocto Project Cookbook - Second Edition

By: Alex Gonzalez

Overview of this book

The Yocto Project has become the de facto distribution build framework for reliable and robust embedded systems with a reduced time to market.You'll get started by working on a build system where you set up Yocto, create a build directory, and learn how to debug it. Then, you'll explore everything about the BSP layer, from creating a custom layer to debugging device tree issues. In addition to this, you’ll learn how to add a new software layer, packages, data, scripts, and configuration files to your system. You will then cover topics based on application development, such as using the Software Development Kit and how to use the Yocto project in various development environments. Toward the end, you will learn how to debug, trace, and profile a running system. This second edition has been updated to include new content based on the latest Yocto release.
Table of Contents (13 chapters)
Title Page
Packt Upsell

Developing with libraries

Most applications make use of shared libraries, which saves system memory and disk space, as they are shared between different applications. Modularizing code into libraries also allows for easier versioning and code management, as well as independent updates from the applications that use them. This recipe will explain how to work with both static and shared libraries.

Getting ready

By convention, library files start with the lib prefix. All libraries need to be explicitly passed to the linker so that they are used, except libc which will be automatically linked. There are basically two library types:

  • Static libraries (.a): When the object code is linked and becomes part of the application.
  • Dynamic libraries (.so): These are linked at compile time but not included in the application, so they need to be available at runtime. Multiple applications can share a dynamic library so they need less disk space.

Libraries are typically placed in the following standard root filesystem...