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The essential reference for core commands that Linux users need daily, along with
superior tutorial on shell programming and much more
o The book is a complete revision of the commands section of Sobell's Practical
o Guide to Linux -- a proven best-seller
o The book is Linux distribution and release agnostic. It will appeal to users of ALL
o Linux distributions.
o ° Superior examples make this book the best option on the market!
Praise for Mark Sobell’s Books
“I keep searching for books that collect everything you want to know about a subject in one place, and keep getting disappointed. Usually the books leave out some important topic, while others go too deep in some areas and must skim lightly over the others. A Practical Guide to Red Hat® Linux® is one of those rare books that actually pulls it off. Mark G. Sobell has created a single reference for Red Hat Linux that cannot be beat! This marvelous text (with a 4-CD set of Linux Fedora Core 2 included) is well worth the price. This is as close to an ‘everything you ever needed to know’ book that I’ve seen. It’s just that good and rates 5 out of 5.”
—Ray Lodato, Slashdot contributor
“Mark Sobell has written a book as approachable as it is authoritative.”
—Jeffrey Bianchine, Advocate, Author, Journalist
“Excellent reference book, well suited for the sysadmin of a linux cluster, or the owner of a PC contemplating installing a recent stable linux. Don’t be put off by the daunting heft of the book. Sobell has striven to be as inclusive as possible, in trying to anticipate your system administration needs.”
—Wes Boudville, Inventor
“A Practical Guide to Red Hat® Linux® is a brilliant book. Thank you Mark Sobell.”
—C. Pozrikidis, University of California at San Diego
“This book presents the best overview of the Linux operating system that I have found. . . . It should be very helpful and understandable no matter what the reader’s background is: traditional UNIX user, new Linux devotee, or even Windows user. Each topic is presented in a clear, complete fashion and very few assumptions are made about what the reader knows. . . . The book is extremely useful as a reference, as it contains a 70-page glossary of terms and is very well indexed. It is organized in such a way that the reader can focus on simple tasks without having to wade through more advanced topics until they are ready.”
—Cam Marshall, Marshall Information Service LLC, Member of Front Range UNIX Users Group FRUUG, Boulder, Colorado
“Conclusively, this is THE book to get if you are a new Linux user and you just got into RH/Fedora world. There’s no other book that discusses so many different topics and in such depth.”The Most Useful Linux Tutorial and Reference Ever, with Hundreds of High-Quality Examples Covering Every Linux Distribution!
—Eugenia Loli-Queru, Editor in Chief, OSNews.com
To be truly productive with Linux, you need to thoroughly master the shells and the command line. Until now, you had to buy two books to gain that mastery: a tutorial on fundamental Linux concepts and techniques, plus a separate reference. Worse, most Linux references offer little more than prettied-up man pages. Now, there’s a far better solution. Renowned Linux expert Mark Sobell has brought together comprehensive, insightful guidance on the tools system administrators, developers, and power users need most, and an outstanding day-to-day reference, both in the same book.
This book is 100 percent distribution and release agnostic: You can use it on any Linux system, now and for years to come. What’s more, it’s packed with hundreds of high-quality examples: better examples than you’ll find in any other Linux guidebook. This is Linux from the ground up: the clearest explanations and most useful knowledge about everything from filesystems to shells, editors to utilities, and programming tools to regular expressions. And when you need instant answers, you’ll constantly turn to Sobell’s comprehensive command reference section—organized and tabbed for easy, fast access!
Don’t settle for yesterday’s Linux guidebook. Get the one book that meets today’s challenges—and tomorrow’s!
A Practical Guide to Linux® Commands, Editors, and Shell Programming is the most useful, most comprehensive Linux tutorial and reference you can find. It’s the only book to deliver
Visit the author's web site: http://www.sobell.com
The GNU-Linux Connection 2
The Heritage of Linux: UNIX 5
What Is So Good About Linux? 6
Overview of Linux 10
Additional Features of Linux 15
Chapter Summary 16
Conventions Used in This Book 22
Logging In 24
Working with the Shell 25
Curbing Your Power: Superuser Access 28
Getting the Facts: Where to Find Documentation 29
More About Logging In 35
Chapter Summary 38
Advanced Exercises 39
Special Characters 42
Basic Utilities 43
Working with Files 45
| (Pipe): Communicates Between Processes 52
Four More Utilities 53
Compressing and Archiving Files 56
Locating Commands 61
Obtaining User and System Information 63
Communicating with Other Users 67
Chapter Summary 69
Advanced Exercises 73
The Hierarchical Filesystem 76
Directory and Ordinary Files 77
Working with Directories 88
Access Permissions 91
Chapter Summary 102
Advanced Exercises 105
The Command Line 108
Standard Input and Standard Output 113
Running a Program in the Background 125
Filename Generation/Pathname Expansion 127
Chapter Summary 133
Advanced Exercises 136
Tutorial: Creating and Editing a File with vim 141
The compatible Parameter 148
Introduction to vim Features 148
Command Mode: Moving the Cursor 154
Input Mode 158
Command Mode: Deleting and Changing Text 160
Searching and Substituting 164
Miscellaneous Commands 170
Yank, Put, and Delete Commands 171
Reading and Writing Files 174
Setting Parameters 175
Advanced Editing Techniques 180
Units of Measure 184
Chapter Summary 188
Advanced Exercises 194
Tutorial: Getting Started with emacs 198
Basic Editing Commands 204
Online Help 209
Advanced Editing 212
Language-Sensitive Editing 225
Customizing emacs 235
More Information 240
Chapter Summary 241
Advanced Exercises 250
Shell Basics 257
Parameters and Variables 277
Controlling bash Features and Options 318
Processing the Command Line 322
Chapter Summary 332
Advanced Exercises 336
Shell Scripts 340
Entering and Leaving the TC Shell 341
Features Common to the Bourne Again and TC Shells 343
Redirecting Standard Error 349
Working with the Command Line 350
Control Structures 368
Chapter Summary 381
Advanced Exercises 384
Programming in C 388
Using Shared Libraries 396
make: Keeps a Set of Programs Current 399
Debugging C Programs 407
System Calls 417
Source Code Management 420
Chapter Summary 430
Advanced Exercises 432
Control Structures 436
File Descriptors 470
Parameters and Variables 474
Builtin Commands 487
Shell Programs 510
Chapter Summary 520
Advanced Exercises 524
Language Basics 530
Advanced gawk Programming 554
Error Messages 559
Chapter Summary 560
Advanced Exercises 561
Editor Basics 565
Chapter Summary 578
Standard Multiplicative Suffixes 586
Common Options 587
The sample Utility 587
sample: Very brief description of what the utility does 588
aspell: Checks a file for spelling errors 589
at: Executes commands at a specified time 593
bzip2: Compresses or decompresses files 596
cal: Displays a calendar 598
cat: Joins and displays files 599
cd: Changes to another working directory 601
chgrp: Changes the group associated with a file 603
chmod: Changes the access mode (permissions) of a file 604
chown: Changes the owner of a file and/or the group the file is associated with 608
cmp: Compares two files 610
comm: Compares sorted files 612
configure: Configures source code automatically 614
cp: Copies files 616
cpio: Creates an archive or restores files from an archive 619
crontab: Maintains crontab files 624
cut: Selects characters or fields from input lines 627
date: Displays or sets the system time and date 630
dd: Converts and copies a file 633
df: Displays disk space usage 636
diff: Displays the differences between two files 638
du: Displays information on disk usage by file 644
echo: Displays a message 647
expr: Evaluates an expression 649
file: Displays the classification of a file 653
find: Finds files based on criteria 655
finger: Displays information about users 661
fmt: Formats text very simply 664
fsck: Checks and repairs a filesystem 666
ftp: Transfers files over a network 671
gcc: Compiles C and C++ programs 678
grep: Searches for a pattern in files 683
gzip: Compresses or decompresses files 688
head: Displays the beginning of a file 691
kill: Terminates a process by PID 693
killall: Terminates a process by name 695
less: Displays text files, one screen at a time 697
ln: Makes a link to a file 702
lpr: Sends files to printers 705
ls: Displays information about one or more files 708
make: Keeps a set of programs current 715
man: Displays documentation for commands 721
mkdir: Creates a directory 724
mkfs: Creates a filesystem on a device 725
Mtools: Uses DOS-style commands on files and directories 728
mv: Renames or moves a file 732
nice: Changes the priority of a command 734
nohup: Runs a command that keeps running after you log out 736
od: Dumps the contents of a file 737
paste: Joins corresponding lines from files 742
pr: Paginates files for printing 744
ps: Displays process status 746
rcp: Copies one or more files to or from a remote system 750
rlogin: Logs in on a remote system 752
rm: Removes a file (deletes a link) 753
rmdir: Removes a directory 755
rsh: Executes commands on a remote system 756
scp: Securely copies one or more files to or from a remote system 758
sleep: Creates a process that sleeps for a specified interval 760
sort: Sorts and/or merges files 762
split: Divides a file in into sections 771
ssh: Securely executes commands on a remote system 773
strings: Displays strings of printable characters 777
stty: Displays or sets terminal parameters 778
tail: Displays the last part (tail) of a file 783
tar: Stores or retrieves files to/from an archive file 786
tee: Copies standard input to standard output and one or more files 791
telnet: Connects to a remote system over a network 792
test: Evaluates an expression 794
top: Dynamically displays process status 798
touch: Changes a file's access and/or modification time 801
tr: Replaces specified characters 804
tty: Displays the terminal pathname 807
tune2fs: Changes parameters on an ext2 or ext3 filesystem 808
umask: Establishes the file-creation permissions mask 810
uniq: Displays unique lines 812
w: Displays information about system users 814
wc: Displays the number of lines, words, and bytes 816
which: Shows where in PATH a command is located 817
who: Displays information about logged-in users 819
xargs: Converts standard input into command lines 821
Simple Strings 828
Special Characters 828
Bracketing Expressions 832
The Replacement String 833
Extended Regular Expressions 834
Appendix Summary 835
Solving a Problem 838
Finding Linux-Related Information 839
Specifying a Terminal 844
yum: Updates and Installs Packages 848
Apt: An Alternative to yum 850
A Practical Guide to Linux ® Commands, Editors, and Shell Programming explains how to work with the Linux operating system from the command line. The first few chapters quickly bring readers with little computer experience up to speed. The rest of the book is appropriate for more experienced computer users. This book does not describe a particular release or distribution of Linux but rather pertains to all recent versions of Linux.
Command line interface (CLI). In the beginning there was the command line (textual) interface (CLI), which enabled you to give Linux commands from the command line. There was no mouse or icons to drag and drop. Some programs, such as emacs , implemented rudimentary windows using the very minimal graphics available in the ASCII character set. Reverse video helped separate areas of the screen. Linux was born and raised in this environment.
Naturally all of the original Linux tools were invoked from the command line. The real power of Linux still lies in this environment, which explains why many Linux professionals work exclusively from the command line. Using clear descriptions and lots of examples, this book shows you how to get the most out of your Linux system using the command line interface.
Linux distributions. A Linux distribution comprises the Linux kernel, utilities, and application programs. Many distributions are available, including Debian, Red Hat, Fedora Core, SUSE, Mandriva (formerly Mandrake), KNOPPIX, and Slackware. Although the distributions differ from one another in various ways, all of them rely on the Linux kernel, utilities, and applications. This book is based on the code that is common to most distributions. As a consequence you can use it regardless of which distribution you are running.
Overlap. If you read A Practical Guide to Red Hat ® Linux, ® Second Edition: Fedora Core ™ and Red Hat Enterprise Linux, or a subsequent edition, you will notice some overlap between that book and the one you are reading now. The introduction, the appendix on regular expressions, and the chapters on the utilities (Chapter 3 of this book-- not Part V), the filesystem, and programming tools are very similar in the two books. The three chapters that cover the Bourne Again shell ( bash ) have been expanded and rewritten for this text. Chapters that appear in this book and but not in A Practical Guide to Red Hat ® Linux, ® Second Edition, include those covering the vim and emacs editors, the TC Shell ( tcsh ), the gawk and sed languages, and Part V, which describes 80 of the most useful Linux utility programs in detail.
Audience. This book is designed for a wide range of readers. It does not require programming experience, although some experience using a general-purpose computer is helpful. It is appropriate for the following readers:
Benefits. A Practical Guide to Linux ® Commands, Editors, and Shell Programming gives you an in-depth understanding of how to use Linux from the command line. Regardless of your background, it offers the knowledge you need to get on with your work: You will come away from this book understanding how to use Linux, and this text will remain a valuable reference for years to come.
This book is organized for ease of use in different situations. For example, you can read it from cover to cover to learn command line Linux from the ground up. Alternatively, once you are comfortable using Linux, you can use this book as a reference: Look up a topic of interest in the table of contents or index and read about it. Or, refer to one of the utilities covered in Part V, "Linux Utility Programs." You can also think of this book as a catalog of Linux topics: Flip through the pages until a topic catches your eye. The book also includes many pointers to Web sites where you can get additional information: Consider the Web an extension of this book.
A Practical Guide to Linux ® Commands, Editors, and Shell Programming offers the following features:
This section describes the information that each chapter covers and explains how that information can help you take advantage of the power of Linux. You may want to review the table of contents for more detail.
Presents background information on Linux. This chapter covers the history of Linux, explains how the GNU project helped Linux get started, and discusses some of Linux's important features that distinguish it from other operating systems.
Part I introduces Linux and gets you started using it.TIP: Experienced Users May Want to Skim Part I
Explains the typographic conventions that this book uses to make explanations clearer and easier to read. This chapter provides basic information and explains how to log in, change your password, give Linux commands using the shell, and find system documentation.
Explains the command line interface (CLI) and briefly introduces more than 30 command line utilities. Working through this chapter gives you a feel for Linux and introduces some of the tools you will use day in and day out. The utilities covered in this chapter include
Discusses the Linux hierarchical filesystem, covering files, filenames, pathnames, working with directories, access permissions, and hard and symbolic links. Understanding the filesystem allows you to organize your data so that you can find information quickly. It also enables you to share some of your files with other users while keeping other files private.
Explains how to use shell features to make your work faster and easier. All of the features covered in this chapter work with both the bash and tcsh shells. This chapter discusses
Part II covers two classic, powerful Linux command line text editors. Most Linux distributions include the vim text editor, an "improved" version of the widely used vim editor, as well as the popular GNU emacs editor. Text editors enable you to create and modify text files that can hold programs, shell scripts, memos, and input to text formatting programs. Because Linux system administration involves editing text-based configuration files, skilled Linux administrators are adept at using text editors.
Starts with a tutorial on vim and then explains how to use many of the advanced features of vim , including special characters in search strings, the General-Purpose and Named buffers, parameters, markers, and execution of commands from vim . The chapter concludes with a summary of vim commands.
Opens with a tutorial and then explains many of the features of the emacs editor as well as how to use the META , ALT , and ESCAPE keys. The chapter also covers key bindings, buffers, and incremental and complete searching for both character strings and regular expressions. In addition, it details the relationship between Point, the cursor, Mark, and Region. It also explains how to take advantage of the extensive online help facilities available from emacs . Other topics covered include cutting and pasting, using multiple windows and frames, and working with emacs modes--specifically C mode, which aids programmers in writing and debugging C code. Chapter 7 concludes with a summary of emacs commands.
Part III goes into more detail about bash and introduces the TC Shell ( tcsh ).
Picks up where Chapter 5 leaves off, covering more advanced aspects of working with a shell. For examples it uses the Bourne Again Shell-- bash , the shell used almost exclusively for system shell scripts. Chapter 8 describes how to
Describes tcsh and covers features that are common to and different between bash and tcsh . This chapter explains how to
Part IV covers programming under Linux. It discusses the C programming environment, the use of bash as a programming language, and ways to write programs using gawk and sed .
Introduces Linux's exceptional programming environment. This chapter
Once you have mastered the basics of Linux, you can use your knowledge to build more complex and specialized programs, using the shell as a programming language.
Shows how to use bash to write advanced shell scripts. This chapter discusses
Chapter 11 poses two complete shell programming problems and then shows you how to solve them step by step. The first problem uses recursion to create a hierarchy of directories. The second problem develops a quiz program and shows you how to set up a shell script that interacts with a user and how the script processes data. (The examples in Part V also demonstrate many features of the utilities you can use in shell scripts.)
Explains how to write programs using the powerful gawk language that filter data, write reports, and retrieve data from the Internet. The advanced programming section describes how to set up two-way communication with another program using a coprocess and how to obtain input over a network instead of from a local file.
Describes sed , the noninteractive stream editor that finds many applications as a filter within shell scripts. This chapter discusses how to use sed 's buffers to write simple yet powerful programs and includes many examples.
Linux includes hundreds of utilities. Chapters 11 and 12 as well as Part V provide extensive examples of the use of more than 80 of the most important utilities with which you can solve problems without resorting to programming in C. If you are already familiar with UNIX/Linux, this part of the book will be a valuable, easy-to-use reference. If you are not an experienced user, it will serve as a useful supplement while you are mastering the earlier sections of the book.
Although the descriptions of the utilities in Chapters 11 and 12 and Part V are presented in a format similar to that used by the Linux manual ( man ) pages, they are much easier to read and understand. These utilities were chosen because you will work with them day in and day out (for example, ls and cp ), because they are powerful tools that are especially useful in shell scripts ( sort , paste , and test ), because they help you work with your Linux system ( ps , kill , and fsck ), or because they enable you to communicate with other systems ( ssh , scp , and ftp ). Each utility description includes complete explanations of its most useful options. The "Discussion" and "Notes" sections present tips and tricks for using the utility to full advantage. The "Examples" sections demonstrate how to use these utilities in real life, alone and together with other utilities to generate reports, summarize data, and extract information. Take a look at the "Examples" sections for gawk , ftp , and sort to see how extensive these sections are.
Part VI includes the appendixes, the glossary, and the index.
Explains how to use regular expressions to take advantage of the hidden power of Linux. Many utilities, including grep , sed , vim , and gawk , accept regular expressions in place of simple strings of characters. A single regular expression can match many simple strings.
Details the steps typically used to solve the problems you may encounter with a Linux system. This appendix also includes many links to Web sites that offer documentation, useful Linux information, mailing lists, and software.
Describes how to use tools to download software and keep your system current. This appendix includes information on
Defines more than 500 terms that pertain to the use of Linux.
Helps you find the information you want quickly.
The author's home page will contain downloadable listings of the longer programs from this book as well as pointers to many interesting and useful Linux-related sites on the World Wide Web, a list of corrections to the book, answers to even-numbered exercises, and a solicitation for corrections, comments, and suggestions.