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)

Deleting files

In this recipe, we learn how to delete files using a system call and where the name—unlink()—comes from. This recipe will enhance your understanding of links and close the circle. This will improve your overall knowledge of Linux and its filesystem. Knowing how to delete files using the system call will enable you to remove files directly from within your programs.

Here we will write our own version of rm, which we will call remove. After this recipe, we know how to create and delete files and how to make links. These are some of the most common filesystem operations.

Getting ready

In this recipe, we will use the my-stat-v1 program, which we wrote in the Reading inode information and learning the filesystem recipe. We will also continue experimenting on the filenames we created in the previous recipes, my-file, another-name, and third-name. Except for that, you'll need what's listed under Technical requirements for this chapter, that...