A Practical Guide to Linux Commands, Editors, and Shell Programming
SECOND EDITION

®

Mark G. Sobell

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Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and the publisher was aware of a trademark claim, the designations have been printed with initial capital letters or in all capitals. The author and publisher have taken care in the preparation of this book, but make no expressed or implied warranty of any kind and assume no responsibility for errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of the use of the information or programs contained herein. The publisher offers excellent discounts on this book when ordered in quantity for bulk purchases or special sales, which may include electronic versions and/or custom covers and content particular to your business, training goals, marketing focus, and branding interests. For more information, please contact: U.S. Corporate and Government Sales (800) 382-3419 corpsales@pearsontechgroup.com For sales outside the United States, please contact: International Sales international@pearson.com Visit us on the Web: informit.com/ph Library of Congress Cataloging-in-Publication Data Sobell, Mark G. A practical guide to Linux commands, editors, and shell programming / Mark G. Sobell.—2nd ed. p. cm. Includes bibliographical references and index. ISBN 978-0-13-136736-4 (pbk.) 1. Linux. 2. Operating systems (Computers) I. Title. QA76.76.O63S59483 2009 005.4'32—dc22 2009038191 Copyright © 2010 Mark G. Sobell All rights reserved. Printed in the United States of America.