Learning the Bash Shell: (A Nutshell handbook)

The first thing users of the Linux operating system come face to face with is the shell. "Shell" is the UNIX term for a user interface to the system -- something that lets you communicate with the computer via the keyboard and display. Bash, the Free Software Foundation's "Bourne Again Shell," is the default shell for Linux, the popular free UNIX-like operating system. It's also a replacement for the standard UNIX Bourne shell, which serves both as a user interface and as a programming language. Like the FSF's other tools, bash is more than a mere replacement: it extends the Bourne shell in many ways. Features include command line editing, key bindings, integrated programming features, command completion, control structures (especially the select construct, which enables you to create menus easily), and new ways to customize your environment. Whether you want to use bash for its user interface or its programming features you will find Learning the bash Shell a valuable guide. The book covers all of bash's features, both for interactive use and programming. If you are new to shell programming, Learning the bash Shell provides an excellent introduction, covering everything from the most basic to the most advanced features, like signal handling and command line processing. If you've been writing shell scripts for years, it offers a great way to find out what the new shell offers. The book is full of examples of shell commands and programs that are designed to be useful in your everyday life as a user, not just to illustrate the feature being explained. All of these examples are freely available to you online on the Internet. This second edition covers all of the features of bash Version 2.0, while still applying to bash Version 1.x. New features include the addition of one-dimensional arrays, parameter expansion, and more pattern-matching operations. bash 2.0 provides even more conformity with POSIX.2 standards, and in POSIX.2 mode is completely POSIX.2 conformant. This second edition covers several new commands, security improvements, additions to ReadLine, improved configuration and installation, and an additional programming aid, the bash shell debugger. With this book you'll 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. Chapter 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. Chapter 2. Command-Line Editing The History File emacs Editing Mode vi Editing Mode The fc Command History Expansion readline Keyboard Habits. Chapter 3. Customizing Your Environment The .bash_profile, .bash_logout, and .bashrc Files Aliases Options Shell Variables Customization and Subprocesses Customization Hints. Chapter 4. Basic Shell Programming Shell Scripts and Functions Shell Variables String Operators Command Substitution Advanced Examples: pushd and popd. Chapter 5. Flow Control if/else for case select while and until. Chapter 6. Command-Line Options and Typed Variables Command-Line Options Typed Variables Integer Variables and Arithmetic Arrays. Chapter 7. Input/Output and Command-Line Processing I/O Redirectors String I/O Command-Line Processing. Chapter 8. Process Handling Process IDs and Job Numbers Job Control Signals trap Coroutines Subshells Process Substitution. Chapter 9. Debugging Shell Programs Basic Debugging Aids A bash Debugger. Chapter 10. bash Administration Installing bash as the Standard Shell Environment Customization System Security Features. Chapter 11. bash for Your System Obtaining bash Unpacking the Archive What's in the Archive Who Do I Turn to? Appendix A. Related Shells. Appendix B. Reference Lists. Appendix C. Loadable Built-Ins. Appendix D. Syntax Appendix. E. Obtaining Sample Programs. Index.

About the Author :
Cameron Newham is an information technology developer living in the United Kingdom. After completing a Bachelor of Science majoring in information technology and geography at the University of Western Australia, Cameron worked for Australian Defence Industries for seven years. He is now an IT contractor based in London. In his spare time Cameron can be found surfing the Internet or working on his project to document buildings of architectural interest in England. He also has more than a passing interest in space science, 3D graphics, synthesizer music, and Depeche Mode. Bill Rosenblatt is author of the the O'Reilly Nutshell Handbook(R) Learning the Korn Shell; coauthor, with Deb Cameron, of Learning GNU Emacs; and a contributor to UNIX Power Tools. He is director of publishing systems at the Times Mirror Company in New York City and a columnist in SunWorld Online magazine on the World Wide Web. Bill received a B.S.E. from Princeton University and an M.S. and A.B.D. from the University of Massachusetts at Amherst, each in some variant of computer science. His interests in the computing field include multimedia databases, electronic publishing, and object-oriented systems. Outside of the computing field, he's interested in jazz, classical music, antique maps, and Sherlock Holmes pastiche novels. Bill lives on the Upper West Side of Manhattan. He wishes his landlord allowed pets so that he could truthfully claim to have a dog and cat with suitably droll names like "Coltrane" and "Ravel."