You're reading from Mastering Embedded Linux Programming - Third Edition

Product type Book

Published in May 2021

Publisher Packt

ISBN-13 9781789530384

Pages 758 pages

Edition 3rd Edition

Languages

Concepts

Embedded Systems

Authors (2):

Frank Vasquez

Chris Simmonds

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Table of Contents (27) Chapters

Preface

1. Section 1: Elements of Embedded Linux

2. Chapter 1: Starting Out

3. Chapter 2: Learning about Toolchains

4. Chapter 3: All about Bootloaders

5. Chapter 4: Configuring and Building the Kernel

6. Chapter 5: Building a Root Filesystem

7. Chapter 6: Selecting a Build System

8. Chapter 7: Developing with Yocto

9. Chapter 8: Yocto Under the Hood

10. Section 2: System Architecture and Design Decisions

11. Chapter 9: Creating a Storage Strategy

12. Chapter 10: Updating Software in the Field

13. Chapter 11: Interfacing with Device Drivers

14. Chapter 12: Prototyping with Breakout Boards

15. Chapter 13: Starting Up – The init Program

16. Chapter 14: Starting with BusyBox runit

17. Chapter 15: Managing Power

18. Section 3: Writing Embedded Applications

19. Chapter 16: Packaging Python

20. Chapter 17: Learning about Processes and Threads

21. Chapter 18: Managing Memory

22. Section 4: Debugging and Optimizing Performance

23. Chapter 19: Debugging with GDB

24. Chapter 20: Profiling and Tracing

25. Chapter 21: Real-Time Programming

26. Other Books You May Enjoy

Using strace

I started the chapter with a simple and ubiquitous tool, top, and I will finish with another: strace. It is a very simple tracer that captures system calls made by a program and, optionally, its children. You can use it to do the following:

Learn which system calls a program makes.
Find those system calls that fail, together with the error code. I find this useful
if a program fails to start but doesn't print an error message or if the message is
too general.
Find which files a program opens.
Find out which syscalls a running program is making, for example, to see whether it is stuck in a loop.

There are many more examples online; just search for strace tips and tricks. Everybody
has their own favorite story, for example, https://alexbilson.dev/posts/strace-debug/.

strace uses the ptrace(2) function to hook calls as they are made from user space to the kernel. If you want to know more about how ptrace works, the manual page is detailed...