Bash Para Principiantes

Machtelt Garrels

Bash Guide for Beginners
Second Edition

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Fultus ™ Books

Bash Guide for Beginners
Second Edition
by

Machtelt Garrels
Cover design by Fultus Corporation

ISBN-10: 1-59682-201-5
ISBN-13: 978-1-59682-201-6
All rights reserved.
Copyright © 2002-2010 by Machtelt Garrels

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Table of Contents

Table of ContentsIntroduction.......................................................................................................................... 12
Chapter 1. Bash and Bash scripts ........................................................................................ 17
1.1. Common shell programs........................................................................................................17
1.1.1. General shell functions....................................................................................................17
1.1.2. Shell types .........................................................................................................................17
1.2. Advantages of the Bourne Again SHell ...............................................................................18
1.2.1. Bash is the GNU shell......................................................................................................18
1.2.2. Features only found in bash ...........................................................................................19
1.3. Executing commands .............................................................................................................25
1.3.1.General...............................................................................................................................25
1.3.2. Shell built-in commands .................................................................................................25
1.3.3. Executing programs from a script .................................................................................26
1.4. Building blocks........................................................................................................................27
1.4.1. Shell building blocks........................................................................................................27
1.5. Developing good scripts ........................................................................................................29
1.5.1. Properties of good scripts...............................................................................................29
1.5.2. Structure ............................................................................................................................30
1.5.3. Terminology......................................................................................................................30
1.5.4. A word on order...