Linux операционни системи

LINUX
IN A NUTSHELLDownload at WoweBook.Com

Download at WoweBook.Com

Sixth Edition
LINUX
IN A NUTSHELL
Ellen Siever, Stephen Figgins, Robert Love,
and Arnold Robbins
Beijing • Cambridge • Farnham • Köln • Sebastopol • Taipei • TokyoDownload at WoweBook.Com

Linux in a Nutshell, Sixth Edition
by Ellen Siever, Stephen Figgins, Robert Love, and Arnold Robbins
Copyright © 2009 Ellen Siever, Stephen Figgins, and Robert Love. All rights reserved.
Printed in the United States of America.
Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472.
O’Reilly books may be purchased for educational, business, or sales promotional use. Online
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Editors:Simon St.Laurent and
Andy Oram
Production Editor:Rachel Monaghan
Indexer:Angela Howard
Production Services:Octal Publishing, Inc.
Cover Designer:Karen Montgomery
Interior Designer:David Futato
Illustrator:Robert Romano
Printing History:
January 1997: First Edition.
February 1999: Second Edition.
August 2000: Third Edition.
June 2003: Fourth Edition.
July 2005: Fifth Edition.
September 2009: Sixth Edition.
Nutshell Handbook, the Nutshell Handbook logo, and the O’Reilly logo are registered
trademarks of O’Reilly Media, Inc. TheIn a Nutshellseries designation,Linux in a Nutshell,
the image of an Arabian horse, and related trade dress are trademarks of O’Reilly Media, Inc.
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While every precaution has been taken in the preparation of this book, the publisher and
authors assume no responsibility for errors or omissions, or for damages resulting from the
use of the information contained herein.
ISBN: 978-0-596-15448-6
[M]Download at WoweBook.Com

v
Chapter 1
Table of Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xv
1. Introduction
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
The Excitement of Linux 2
Distribution and Support 3
Commands on Linux 3
What This Book Offers 4
Sources and Licenses 6
Beginner’s Guide 7
Communication 7
Comparisons 8
File Management 8
Media 9
Printing 9
Programming 9
Program Maintenance 10
Searching 10
Shell Programming 11
Storage 11
System Status 11
Text Processing 12
Miscellaneous 13Download at WoweBook.Com

vi|Table of Contents
2. System and Network Administration Overview. . . . . . . . . . . . . . . . .14
Common Commands 14
Clocks 14
Daemons 14
Hardware 15
Host Information 15
Installation 16
Mail 16
Managing Filesystems 16
Managing the Kernel 17
Networking 18
Printing 18
Security and System Integrity 18
Starting and Stopping the System 19
System Activity and Process Management 19
Users 20
Miscellaneous 20
Overview of Networking 21
TCP/IP Administration 21
NFS and NIS Administration 22
Overview of TCP/IP 22
IP Addresses 23
Gateways and Routing 25
Name Service 26
Configuring TCP/IP 27
Troubleshooting TCP/IP 28
Overview of Firewalls and Masquerading 28
Overview of NFS 29
Administering NFS 30
Daemons 30
Exporting Filesystems 30
Mounting Filesystems 30
Overview of NIS 31
Servers 31
Domains 31
NIS Maps 31
Map Manipulation Utilities 31Download at WoweBook.Com

Table of Contents | vii
Administering NIS 32
Setting Up an NIS Server 32
Setting Up an NIS Client 32
NIS User Accounts 32
RPC and XDR 32
3. Linux Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Alphabetical Summary of Commands 34
4. Boot Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .504
The Boot Process 505
LILO: The Linux Loader 506
The LILO Configuration File 507
The lilo Command 514
lilo Command Options 515
LILO Boot Errors 516
GRUB: The Grand Unified Bootloader 516
Installing GRUB 518
The GRUB Configuration File 521
Using the Menu Interface 523
The GRUB Shell 523
GRUB Commands 525
Command-Line and Global Menu Commands 526
Command-Line and Menu-Entry Commands 530
Dual-Booting Linux and Windows 2000/XP/Vista 536
Boot-Time Kernel Options 539
initrd: Using a RAM Disk 541
5. Package Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .542
Yum: Yellowdog Updater Modified 545
The yum Command 545
yum Command Summary 547
Plugins and yum-utils 551
The Red Hat Package Manager 552
RPM Package Concepts 552
The rpm Command 553
RPM Examples 563
The rpmbuild Command 564Download at WoweBook.Com

viii|Table of Contents
The Debian Package Manager 565
Files 565
Package Priorities 566
Package and Selection States 567
Package Flags 567
Scripts 568
Debian Package Manager Command Summary 569
6. The Bash Shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .596
Overview of Features 597
Invoking the Shell 597
Options 598
Arguments 599
Syntax 599
Special Files 599
Filename Metacharacters 599
Quoting 600
Command Forms 602
Redirection Forms 602
Coprocesses 604
Functions 605
Variables 606
Variable Substitution 606
Built-in Shell Variables 607
Other Shell Variables 609
Arrays 611
Special Prompt Strings 612
Arithmetic Expressions 613
Operators 613
Examples 613
Command History 614
Line-Edit Mode 614
The fc Command 614
Programmable Completion 615
Job Control 617
Command Execution 618
Restricted Shells 619
Built-in Commands 619Download at WoweBook.Com

Table of Contents | ix
7. Pattern Matching. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .654
Filenames Versus Patterns 654
Metacharacters 655
Search Patterns 655
Replacement Patterns 656
Metacharacters, Listed by Program 657
Examples of Searching 658
Examples of Searching and Replacing 659
8. The Emacs Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .661
Conceptual Overview 661
Modes 661
Buffer and Window 662
Point and Mark 662
Kill and Yank 662
Notes on the Tables 662
Absolutely Essential Commands 663
Command-Line Syntax 663
Summary of Commands by Group 663
File-Handling Commands 663
Cursor-Movement Commands 664
Deletion Commands 664
Paragraphs and Regions 665
Stopping and Undoing Commands 665
Transposition Commands 665
Search Commands 665
Capitalization Commands 666
Word-Abbreviation Commands 666
Buffer-Manipulation Commands 666
Window Commands 666
Special Shell Characters 667
Indentation Commands 667
Centering Commands 668
Macro Commands 668
Detail Information Help Commands 668
Help Commands 669Download at WoweBook.Com

x|Table of Contents
Summary of Commands by Key 669
Control-Key Sequences 669
Meta-Key Sequences 671
Summary of Commands by Name 672
9. The vi, ex, and vim Editors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .677
Conceptual Overview 677
Command-Line Syntax 678
Command-Line Options 678
Review of vi Operations 681
Command Mode 681
Insert Mode 681
Syntax of vi Commands 681
Status-Line Commands 683
vi Commands 683
Movement Commands 683
Insert Commands 686
Edit Commands 687
Saving and Exiting 688
Accessing Multiple Files 689
Window Commands 689
Interacting with the System 690
Macros 691
Miscellaneous Commands 691
vi Configuration 692
The :set Command 692
Options Used by :set 692
Sample .exrc File 696
ex Basics 696
Syntax of ex Commands 696
Addresses 696
Address Symbols 697
Options 697
Alphabetical Summary of ex Commands 697Download at WoweBook.Com

Table of Contents | xi
10. The sed Editor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .711
Conceptual Overview 711
Typical Uses of sed 711
sed Operation 712
Command-Line Syntax 712
Standard Options 712
GNU sed Options 713
Syntax of sed Commands 713
Pattern Addressing 714
Pattern Addressing Examples 714
GNU sed Regular Expression Extensions 715
Group Summary of sed Commands 715
Basic Editing 716
Line Information 716
Input/Output Processing 716
Yanking and Putting 716
Branching Commands 717
Multiline Input Processing 717
Alphabetical Summary of sed Commands 717
11. The gawk Programming Language . . . . . . . . . . . . . . . . . . . . . . . . . .726
Conceptual Overview 726
Command-Line Syntax 727
Standard Options 728
Important gawk Options 728
Patterns and Procedures 729
Patterns 729
Procedures 730
Simple Pattern-Procedure Examples 730
Built-in Variables 731
Operators 732
Variable and Array Assignment 732
Escape sequences 733
Octal and Hexadecimal Constants in gawk 734
User-Defined Functions 734Download at WoweBook.Com

xii|Table of Contents
gawk-Specific Features 735
Coprocesses and Sockets 735
Profiling 735
File Inclusion 736
Internationalization 736
Implementation Limits 737
Group Listing of awk Functions and Commands 737
Alphabetical Summary of awk Functions and Commands 738
Output Redirections 746
printf Formats 746
12. Source Code Management: AnOverview . . . . . . . . . . . . . . . . . . . . .749
Introduction and Terminology 749
Usage Models 751
Source Code Management Systems 752
Other Source Code Management Systems 753
13. The Subversion Version Control System. . . . . . . . . . . . . . . . . . . . . . .755
Conceptual Overview 755
Basic Version-Control Operations 755
Key Features 756
Special File Properties 757
Obtaining Subversion 759
Using Subversion: A Quick Tour 759
The Subversion Command Line Client: svn 761
Common svn Options 761
svn Subcommands 766
Repository Administration: svnadmin 794
Common svnadmin Options 794
Common svnadmin Subcommands 795
Examining the Repository: svnlook 799
svnlook Options 799
svnlook Subcommands 800
Providing Remote Access: svnserve 803
svnserve Options 804Download at WoweBook.Com

Table of Contents | xiii
14. The Git Version Control System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .805
Conceptual Overview 805
Git Repository Format 806
Referring to Commits 806
Using Git: A Quick Tour 808
Before You Start 808
Example: The Linux Kernel Repository 809
Creating and Sharing a New Repository 810
The Git Command Line Client: git 811
The git Command 811
Accessing Git’s Online Help 812
git Subcommands 812
15. Virtualization Command-LineTools. . . . . . . . . . . . . . . . . . . . . . . . . .837
Conceptual Overview 838
System Requirements 838
Virtualization Technology 839
Network Concepts 839
libvirt Tools and Terminology 839
Basic Virtualization Operations 840
Creating Virtual Systems 840
Managing Virtual Systems 841
Graphic and Console Interfaces 842
Configuring Networks 842
MAC Addresses 844
Making Changes to Virtual Machines 844
Creating and Manipulating Disk Image Files 844
Xen 845
Paravirtualization and Architecture 846
Xen Networking 846
Xen Commands 846
KVM 849
QEMU 849
Ubuntu Builder Scripts 850Download at WoweBook.Com

xiv|Table of Contents
libvirt and Red Hat Virtual Machine Manager 850
XML Configuration Files 850
Connection URIs 850
Connection URI Examples 850
Remote GUI control 851
IP Forwarding and libvirt Networking 851
libvirt and Virtual Machine Manager Commands 852
VMware ESX 3.5 862
ESX Management Client 862
Virtual Center 862
VMware Networking 863
Shared Disks 863
Snapshots 863
VMware Tools 864
ESX Server Commands 864
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .875Download at WoweBook.Com

xv
This is the Title of the Book, eMatter Edition
Copyright © 2009 O’Reilly & Associates, Inc. All rights reserved.
Chapter 2
Preface
This is a book about Linux, a freely available clone of the Unix operating system
whose uses range from embedded systems and personal data assistants (PDAs) to
corporate servers, web servers, and massive clusters that perform some of the
world’s most difficult computations.
Whether you are