Arnold Robbins - Bash Pocket Reference: Help for Power Users and Sys Admins

by Arnold Robbins

Copyright 2016 Arnold Robbins. All rights reserved.

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• March 2016: Second Edition

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978-1-491-94159-1

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This pocket reference covers Bash, particularly version 4.4, the primary shell for GNU/Linux and Mac OS X. Bash is available for Solaris and the various BSD systems, and can be easily compiled for just about any other Unix system. It can even be compiled for OpenVMS! The following topics are covered:

• History
• Overview of features
• Invoking the shell
• Command exit status
• Syntax
• Functions
• Variables
• Arithmetic expressions
• Command history
• Programmable completion
• Job control
• Shell options
• Command execution
• Coprocesses
• Restricted shells
• Built-in commands
• Resources

Filenames, command names, options, and inline examples are shown in constantwidth. Input that a user should type in exactly as-is is shown in constantwidthuserinput. Text that should be replaced with real data in examples and syntax descriptions is shown in constantwidthreplaceable. New terms and emphasized words and phrases are shown in italics. Finally, references of the form name(N) refer to the manual page for name in section N of the online manual (accessed via the man command). Shell variable values (including environment variables) are indicated as $VAR.