learning the bash shell

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• Table of

Contents

• Index

• Reviews

• Examples

• Reader

Reviews

• Errata

Ripped by Caudex 2003

This second edition covers all of the features of bash Version 2.0, while still

applying to bash Version 1.x. It includes one−dimensional arrays, parameter

expansion, more pattern−matching operations, new commands, security

improvements, additions to ReadLine, improved configuration and installation,

and an additional programming aid, the bash shell debugger.

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Copyright © 1998, 1995 O'Reilly & Associates, Inc. All rights reserved.

appear in this book, and O'Reilly & Associates, Inc. was aware of a trademark claim, the designations have

been printed in caps or initial caps. The use of the fish image in association with the bash shell is a trademark

of O'Reilly & Associates, Inc.

While every precaution has been taken in the preparation of this book, the publisher assumes no responsibility

for errors or omissions, or for damages resulting from the use of the information contained herein.

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these standard shells are rather old and lack many features of the newer shells. This is a shame, because shells

have a large bearing on one's working environment. Since changing shells is as easy as changing hats, there is

no reason not to change to the latest and greatest in shell technology.

Of the many shells to choose from, this book introduces the Bourne Again shell (bash for short), a modern

general−purpose shell. Other useful modern shells are the Korn shell (ksh) and the "Tenex C shell" (tcsh);

both are also the subjects of O'Reilly handbooks.

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Preface 3

bash Versions

This book is relevant to all versions of bash, although older versions lack some of the features of the most

recent version.

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bash Versions 4

Summary of bash Features

bash is a backward−compatible evolutionary successor to the Bourne shell that includes most of the C shell's

major advantages as well as features from the Korn shell and a few new features of its own. Features

· Brace expansion, for generating arbitrary strings.

· Tilde expansion, a shorthand way to refer to directories.

· Aliases, which allow you to define shorthand names for commands or command lines.

· Command history, which lets you recall previously entered commands.

bash's major new features include:

· Command−line editing, allowing you to use vi− or emacs−style editing commands on your command

lines.

· Key bindings that allow you to set up customized editing key sequences.

· Integrated programming features: the functionality of several external UNIX commands, including test,

expr, getopt, and echo, has been integrated into the shell itself, enabling common programming tasks to be

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Summary of bash Features 5