Book Image

Embedded Linux Development using Yocto Projects - Second Edition

By : Otavio Salvador, Daiane Angolini
Book Image

Embedded Linux Development using Yocto Projects - Second Edition

By: Otavio Salvador, Daiane Angolini

Overview of this book

Yocto Project is turning out to be the best integration framework for creating reliable embedded Linux projects. It has the edge over other frameworks because of its features such as less development time and improved reliability and robustness. Embedded Linux Development using Yocto Project starts with an in-depth explanation of all Yocto Project tools, to help you perform different Linux-based tasks. The book then moves on to in-depth explanations of Poky and BitBake. It also includes some practical use cases for building a Linux subsystem project using Yocto Project tools available for embedded Linux. The book also covers topics such as SDK, recipetool, and others. By the end of the book, you will have learned how to generate and run an image for real hardware boards and will have gained hands-on experience at building efficient Linux systems using Yocto Project.
Table of Contents (22 chapters)
Title Page
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
7
Diving into BitBake Metadata
Index

Dependencies


In order to accomplish the dependency, the recipes must declare what dependencies they need to have available during the build process. BitBake ensures that the build-time dependencies are satisfied before starting to buildthe recipe. This is easier to understand if we think about an application that uses a library. So, this library must be built and its headers must be made available for use before the application itself can be built. TheDEPENDSvariable is used in a recipe to inform BitBake about the build-time dependency and we should list another recipe.

When an application depends on something to run, it is called a runtime dependency. This is common for shared data among applications (for example, icons) that is used only when running the application or when an application calls another application during its execution that is not used during its build process. The runtime dependencies can be expressed using the RDEPENDS variable in a recipe. However, as those are meant...