Learning the Bash Shell by Newham, Cameron

O'Reilly's bestselling book on Linux's bash shell is at it again. Now that Linux is an established player both as a server and on the desktop Learning the bash Shell has been updated and refreshed to account for all the latest changes. Indeed, this third edition serves as the most valuable guide yet to the bash shell. As any good programmer knows, the first thing users of the Linux operating system come face to face with is the shell the UNIX term for a user interface to the system. In other words, it's what lets you communicate with the computer via the keyboard and display. Mastering the bash shell might sound fairly simple but it isn't. In truth, there are many complexities that need careful explanation, which is just what Learning the bash Shell provides. If you are new to shell programming, the book provides an excellent introduction, covering everything from the most basic to the most advanced features. And if you've been writing shell scripts for years, it offers a great way to find out what the new shell offers. Learning the bash Shell is also full of practical examples of shell commands and programs that will make everyday use of Linux that much easier.;With this book, programmers will learn: How to install bash as your login shell The basics of interactive shell use, including UNIX file and directory structures, standard I/O, and background jobs Command line editing, history substitution, and key bindings How to customize your shell environment without programming The nuts and bolts of basic shell programming, flow control structures, command-line options and typed variables Process handling, from job control to processes, coroutines and subshells Debugging techniques, such as trace and verbose modes Techniques for implementing system-wide shell customization and features related to system security

Table of Contents

Preface 1. bash Basics What Is a Shell? Scope of This Book; History of UNIX Shells Getting bash Interactive Shell Use; Files Input and Output Background Jobs Special Characters and Quoting Help 2. Command-Line Editing Enabling Command-Line Editing The History List emacs Editing Mode; vi Editing Mode The fc Command History Expansion readline; Keyboard Habits 3. Customizing Your Environment; The .bash_profile, .bash_logout, and .bashrc Files Aliases; Options Shell Variables Customization and Subprocesses; Customization Hints 4. Basic Shell Programming Shell Scripts and Functions Shell Variables String Operators Command Substitution Advanced Examples: pushd and popd 5. Flow Control; if/else for case select while and until 6. Command-Line Options and Typed Variables Command-Line Options Typed Variables; Integer Variables and Arithmetic Arrays 7. Input/Output and Command-Line Processing I/O Redirectors String I/O Command-Line Processing 8. Process Handling Process IDs and Job Numbers Job Control Signals trap Coroutines Subshells; Process Substitution 9. Debugging Shell Programs Basic Debugging Aids A bash Debugger 10. bash Administration Installing bash as the Standard Shell Environment Customization System Security Features 11. Shell Scripting What's That Do? Starting Up; Potential Problems Don't Use bash 12. bash for Your System; Obtaining bash Unpacking the Archive What's in the Archive; Who Do I Turn to? A. Related Shells The Bourne Shell The IEEE 1003.2 POSIX Shell Standard The Korn Shell pdksh; zsh Shell Clones and Unix-like Platforms B. Reference Lists; Invocation Prompt String Customizations Built-In Commands and Reserved Words Built-In Shell Variables Test Operators; set Options shopt Options I/O Redirection emacs Mode Commands vi Control Mode Commands C. Loadable Built-Ins; D. Programmable Completion Index