Book Image

Linux System Programming Techniques

By : Jack-Benny Persson
Book Image

Linux System Programming Techniques

By: Jack-Benny Persson

Overview of this book

Linux is the world's most popular open source operating system (OS). Linux System Programming Techniques will enable you to extend the Linux OS with your own system programs and communicate with other programs on the system. The book begins by exploring the Linux filesystem, its basic commands, built-in manual pages, the GNU compiler collection (GCC), and Linux system calls. You'll then discover how to handle errors in your programs and will learn to catch errors and print relevant information about them. The book takes you through multiple recipes on how to read and write files on the system, using both streams and file descriptors. As you advance, you'll delve into forking, creating zombie processes, and daemons, along with recipes on how to handle daemons using systemd. After this, you'll find out how to create shared libraries and start exploring different types of interprocess communication (IPC). In the later chapters, recipes on how to write programs using POSIX threads and how to debug your programs using the GNU debugger (GDB) and Valgrind will also be covered. By the end of this Linux book, you will be able to develop your own system programs for Linux, including daemons, tools, clients, and filters.
Table of Contents (14 chapters)

Chapter 12: Debugging Your Programs

No program is perfect on the first try. In this chapter, we'll learn how to debug our programs using GDB and Valgrind. With the latter tool, Valgrind, we can find memory leaks in our programs.

We'll also take a look at what memory leaks are, what they can cause, and how to prevent them. Debugging programs and looking at memory is an important step to understanding system programming fully.

In this chapter, we will cover the following recipes:

  • Starting GDB
  • Stepping inside functions with GDB
  • Investigating memory with GDB
  • Modifying variables during runtime
  • Using GDB on a program that forks
  • Debugging programs with multiple threads
  • Finding a simple memory leak with Valgrind
  • Finding buffer overflows with Valgrind