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)

Starting GDB

In this recipe, we'll learn the basics of GDB, the GNU debugger. We'll learn how to start GDB, how to set a breakpoint, and how to step forward in a program, one step at a time. We'll also learn what debugging symbols are and how we enable them.

GDB is the most popular debugger for Linux and other Unix-like systems. It allows you to examine—and change—variables on the fly, step through instructions one at a time, view the code as the program is running, read return values, and much more.

Knowing how to use a debugger can save you many hours of frustration. Instead of guessing what the problem is with your program, you can follow the execution with GDB and spot the error. This can save you a lot of time.

Getting ready

For this recipe, you'll need the GCC compiler, the Make tool, and the GDB tool. For installation instructions for GDB, see the Technical requirements section of this chapter.

How to do it…

In this...