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

Logging information during task execution


The logging utilities provided by BitBake are very useful for tracing the code execution path. BitBake provides logging functions for use in Python and Shell Script code, described as follows:

  • Python: For use within Python functions, BitBake supports several log levels, which are bb.fatal, bb.error, bb.warn, bb.note, bb.plain, and bb.debug
  • Shell Script: For use in Shell Script functions, the same set of log levels exists and is accessed with a similar syntax: bbfatal, bberror, bbwarn, bbnote, bbplain, and bbdebug

These logging functions are very similar to each other but have inner differences, described as follows:

  • bb.fatal and bbfatal: These have the highest priority of logging messages as they print the message and terminate the processing. They cause the build to be interrupted.
  • bb.error and bberror: These are used to display an error but do not force the build to stop.
  • bb.warn and bbwarn: These are used to warn users about something.
  • bb.note and bbnote...