Pro Bash Programming: Scripting the GNU/Linux Shell

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 4.0 programs through standard programming techniques.

• Complete bash coverage
• Teaches bash as a programming language
• Helps you master bash 4.0 features

• Use 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.

Beginning Linux and Unix system administrators who want to be in full command of their systems.

Table of Contents

1. Hello, World! Your First Shell Program
2. Input, Output, and Throughput
3. Looping and Branching
4. Command-Line Parsing and Expansion
5. Parameters and Variables
6. Shell Functions
7. String Manipulation
8. File Operations and Commands
9. Reserved Words and Builtin Commands
10. Writing Bug-Free Scripts and Debugging the Rest
11. Programming for the Command Line
12. Runtime Configuration
13. Data Processing
14. Scripting the Screen
15. Entry-Level Programming

This is the only book that treats the shell as a full programming language. It is also the only book that will include bash 4.0 features.

Chris F.A. Johnson was introduced to Unix in 1990, and learned shell scripting because there was no C compiler on the system. His first major project was a menu-driven, user-extensible database system with report generator. Chris uses the shell as his primary, general-purpose programming language, and his projects have included a member database, menuing system, and POP3 mail filtering and retrieval. Chris is the author of "Shell Scripting Recipes: A Problem-Solution Approach" (Apress 2005). When not pushing shell scripting to the limit, he designs and codes web sites, teaches chess, and composes cryptic crosswords.