Pro Bash Programming, Second Edition: Scripting the GNU/Linux Shell

Pro Bash Programming teaches you how to effectively utilize the Bash shell in your programming. The Bash shell is a complete programming language, not merely a glue to combine external Linux commands. By taking full advantage of Shell internals, Shell programs can perform as snappily as utilities written in C or other compiled languages. And you will see how, without assuming Unix lore, you can write professional Bash 4.3 programs through standard programming techniques.This second edition has updated for Bash 4.3, and many scripts have been rewritten to make them more idiomatically Bash, taking better advantage of features specific to Bash. It is easy to read, understand, and will teach you how to get to grips with Bash programming without drowning you in pages and pages of syntax. Using this book you will be able to use the shell efficiently, make scripts run faster using expansion and external commands, and understand how to overcome many common mistakes that cause scripts to fail. This book is perfect for all beginning Linux and Unix system administrators who want to be in full control of their systems, and really get to grips with Bash programming. What you’ll learnUse the shell to write new utilities and accomplish most programming tasks.Use shell parameter expansion to replace many external commands, making scripts very fast.Learn to avoid many common mistakes that cause scripts to fail.Learn how Bash’s readline and history libraries can save typing when getting user input.Learn to use features new to Bash 4.0.Build shell scripts that get information from the Web.Who this book is for Beginning Linux and Unix system administrators who want to be in full command of their systems. Table of ContentsChapter One: Hello, World! Your First Shell Program Chapter Two: Input, Output, and Throughput Chapter Three: Looping and Branching Chapter Four: Command-Line Parsing and Expansion Chapter Five: Parameters and Variables Chapter Six: Shell Functions Chapter Seven: String Manipulation Chapter Eight: File Operations and Commands Chapter Nine: Reserved Words and Builtin Commands Chapter Ten: Writing Bug-Free Scripts and Debugging the Rest Chapter Eleven: Programming for the Command Line Chapter Twelve: Runtime Configuration Chapter Thirteen: Data Processing Chapter Fourteen: Scripting the Screen Chapter Fifteen: Entry-Level ProgrammingAppendix A: Shell Variables