• Table of Contents
• Index
• Reviews
• Reader Reviews
• Errata
UNIX Power Tools, 3rd Edition
By Shelley Powers, Jerry Peek, Tim O'Reilly, Mike Loukides, et. al.
Publisher : O'Reilly
Pub Date : October 2002 ISBN : 0-596-00330-7 Pages : 1136
The latest edition of this best-selling favorite is loaded with vital information on Linux, Darwin, and BSD. Unix Power Tools 3rd Edition now offers more coverage of bash, zsh, and other new shells, along with discussions about modern utilities and
applications. Several sections focus on security and Internet access. There is a new chapter on access to Unix from
Windows, and expanded coverage of software installation and packaging, as well as basic information on Perl and Python.
777
Copyright
How to Use This Book Preface
A Book for Browsing Like an Almanac Like a News Magazine Like a Hypertext Database Programs on the Web About Unix Versions Cross-References
What's New in the Third Edition Typefaces and Other Conventions The Authors
The Fine Print
Request for Comments
Acknowledgments for the First Edition Acknowledgments for the Second Edition Acknowledgments for the Third Edition
Part I: Basic Unix Environment Chapter 1. Introduction
Section 1.1. What's Special About Unix?
Section 1.2. Power Grows on You Section 1.3. The Core of Unix
Section 1.4. Communication with Unix
Section 1.5. Programs Are Designed to Work Together Section 1.6. There Are Many Shells
Section 1.7. Which Shell Am I Running?
Section 1.8. Anyone Can Program the Shell Section 1.9. Internal and External Commands Section 1.10. The Kernel and Daemons Section 1.11. Filenames
Section 1.12. Filename Extensions
Section 1.13. Wildcards
Section 1.14. The Tree Structure of the Filesystem Section 1.15. Your Home Directory
Section 1.16. Making Pathnames Section 1.17. File Access Permissions Section 1.18. The Superuser (Root) Section 1.19. When Is a File Not a File?
Section 1.20. Scripting
Section 1.21. Unix Networking and Communications Section 1.22. The X Window System
Chapter 2. Getting Help
Section 2.1. The man Command
Section 2.2. whatis: One-Line Command Summaries
Section 2.3. whereis: Finding Where a Command Is Located Section 2.4. Searching Online Manual Pages
Section 2.5. How Unix Systems Remember Their Names Section 2.6. Which Version Am I Using?
Section 2.7. What tty Am I On?
Section 2.8. Who's On?
Section 2.9. The info Command
Part II: Customizing Your Environment Chapter 3. Setting Up Your Unix Shell
Section 3.1. What Happens When You Log In Section 3.2. The Mac OS X Terminal Application
Section 3.3. Shell Setup Files — Which, Where, and Why Section 3.4. Login Shells, Interactive Shells
Section 3.5. What Goes in Shell Setup Files?
Section 3.6. Tip for Changing Account Setup: Keep a Shell Ready Section 3.7. Use Absolute Pathnames in Shell Setup Files
Section 3.8. Setup Files Aren't Read When You Want?
Section 3.9. Gotchas in set prompt Test
Section 3.10. Automatic Setups for Different Terminals Section 3.11. Terminal Setup: Testing TERM
Section 3.12. Terminal Setup: Testing Remote Hostname and X Display Section 3.13. Terminal Setup: Testing Port
Section 3.14. Terminal Setup: Testing Environment Variables Section 3.15. Terminal Setup: Searching Terminal Table Section 3.16. Terminal Setup: Testing Window Size
Section 3.17. Terminal Setup: Setting and Testing Window Name Section 3.18. A .cshrc.$HOST File for Per Host Setup
Section 3.19. Making a "Login" Shell Section 3.20. RC Files
Section 3.21. Make Your Own Manpages Without Learning troff Section 3.22. Writing a Simple Manpage with the -man Macros
Chapter 4. Interacting with Your Environment Section 4.1. Basics of Setting the Prompt Section 4.2. Static Prompts
Section 4.3. Dynamic Prompts
Section 4.4. Simulating Dynamic Prompts
Section 4.5. C-Shell Prompt Causes Problems in vi, rsh, etc.
Section 4.6. Faster Prompt Setting with Built-ins Section 4.7. Multiline Shell Prompts
Section 4.8. Session Info in Window Title or Status Line Section 4.9. A "Menu Prompt" for Naive Users
Section 4.10. Highlighting and Color in Shell Prompts Section 4.11. Right-Side Prompts
Section 4.12. Show Subshell Level with $SHLVL Section 4.13. What Good Is a Blank Shell Prompt?
Section 4.14. dirs in Your Prompt: Better Than $cwd
Section 4.15. External Commands Send Signals to Set Variables Section 4.16. Preprompt, Pre-execution, and Periodic Commands Section 4.17. Running Commands When You Log Out
Section 4.18. Running Commands at Bourne/Korn Shell Logout Section 4.19. Stop Accidental Bourne-Shell Logouts
Chapter 5. Getting the Most out of Terminals, xterm, and X Windows Section 5.1. There's a Lot to Know About Terminals
Section 5.2. The Idea of a Terminal Database
Section 5.3. Setting the Terminal Type When You Log In Section 5.4. Querying Your Terminal Type: qterm
Section 5.5. Querying Your xterm Size: resize
Section 5.6. Checklist: Terminal Hangs When I Log In Section 5.7. Find Out Terminal Settings with stty
Section 5.8. Setting Your Erase, Kill, and Interrupt Characters Section 5.9. Working with xterm and Friends
Section 5.10. Login xterms and rxvts Section 5.11. Working with Scrollbars Section 5.12. How Many Lines to Save?
Section 5.13. Simple Copy and Paste in xterm
Section 5.14. Defining What Makes Up a Word for Selection Purposes Section 5.15. Setting the Titlebar and Icon Text
Section 5.16. The Simple Way to Pick a Font Section 5.17. The xterm Menus
Section 5.18. Changing Fonts Dynamically Section 5.19. Working with xclipboard
Section 5.20. Problems with Large Selections
Section 5.21. Tips for Copy and Paste Between Windows Section 5.22. Running a Single Command with xterm -e Section 5.23. Don't Quote Arguments to xterm -e
Chapter 6. Your X Environment
Section 6.1. Defining Keys and Button Presses with xmodmap Section 6.2. Using xev to Learn Keysym Mappings
Section 6.3. X Resource Syntax Section 6.4. X Event Translations
Section 6.5. Setting X Resources: Overview
Section 6.6. Setting Resources with the -xrm Option Section 6.7. How -name Affects Resources
Section 6.8. Setting Resources with xrdb
Section 6.9. Listing the Current Resources for a Client: appres Section 6.10. Starting Remote X Clients
Part III: Working with Files and Directories
Chapter 7. Directory Organization
Section 7.1. What? Me, Organized?
Section 7.2. Many Homes
Section 7.3. Access to Directories
Section 7.4. A bin Directory for Your Programs and Scripts Section 7.5. Private (Personal) Directories
Section 7.6. Naming Files
Section 7.7. Make More Directories!
Section 7.8. Making Directories Made Easier
Chapter 8. Directories and Files
Section 8.1. Everything but the find Command Section 8.2. The Three Unix File Times
Section 8.3. Finding Oldest or Newest Files with ls -t and ls -u Section 8.4. List All Subdirectories with ls -R
Section 8.5. The ls -d Option Section 8.6. Color ls
Section 8.7. Some GNU ls Features
Section 8.8. A csh Alias to List Recently Changed Files Section 8.9. Showing Hidden Files with ls -A and -a Section 8.10. Useful ls Aliases
Section 8.11. Can't Access a File? Look for Spaces in the Name Section 8.12. Showing Nonprintable Characters in Filenames Section 8.13. Counting Files by Types
Section 8.14. Listing Files by Age and Size
Section 8.15. newer: Print the Name of the Newest File Section 8.16. oldlinks: Find Unconnected Symbolic Links Section 8.17. Picking a Unique Filename Automatically
Chapter 9. Finding Files with find Section 9.1. How to Use find
Section 9.2. Delving Through a Deep Directory Tree Section 9.3. Don't Forget -print
Section 9.4. Looking for Files with Particular Names Section 9.5. Searching for Old Files
Section 9.6. Be an Expert on find Search Operators Section 9.7. The Times That find Finds
Section 9.8. Exact File-Time Comparisons
Section 9.9. Running Commands on What You Find Section 9.10. Using -exec to Create Custom Tests Section 9.11. Custom -exec Tests Applied
Section 9.12. Finding Many Things with One Command Section 9.13. Searching for Files by Type
Section 9.14. Searching for Files by Size Section 9.15. Searching for Files by Permission Section 9.16. Searching by Owner and Group Section 9.17. Duplicating a Directory Tree Section 9.18. Using "Fast find" Databases
Section 9.19. Wildcards with "Fast find" Database
Section 9.20. Finding Files (Much) Faster with a find Database Section 9.21. grepping a Directory Tree
Section 9.22. lookfor: Which File Has That Word?
Section 9.23. Using Shell Arrays to Browse Directories Section 9.24. Finding the (Hard) Links to a File
Section 9.25. Finding Files with -prune
Section 9.26. Quick finds in the Current Directory Section 9.27. Skipping Parts of a Tree in find
Section 9.28. Keeping find from Searching Networked Filesystem
Chapter 10. Linking, Renaming, and Copying Files
Section 10.1. What's So Complicated About Copying Files Section 10.2. What's Really in a Directory?
Section 10.3. Files with Two or More Names Section 10.4. More About Links
Section 10.5. Creating and Removing Links Section 10.6. Stale Symbolic Links
Section 10.7. Linking Directories
Section 10.8. Showing the Actual Filenames for Symbolic Links Section 10.9. Renaming, Copying, or Comparing a Set of Files Section 10.10. Renaming a List of Files Interactively
Section 10.11. One More Way to Do It
Section 10.12. Copying Directory Trees with cp -r
Section 10.13. Copying Directory Trees with tar and Pipes
Chapter 11. Comparing Files
Section 11.1. Checking Differences with diff
Section 11.2. Comparing Three Different Versions with diff3 Section 11.3. Context diffs
Section 11.4. Side-by-Side diffs: sdiff Section 11.5. Choosing Sides with sdiff
Section 11.6. Problems with diff and Tabstops Section 11.7. cmp and diff
Section 11.8. Comparing Two Files with comm Section 11.9. More Friendly comm Output Section 11.10. make Isn't Just for Programmers!
Section 11.11. Even More Uses for make
Chapter 12. Showing What's in a File Section 12.1. Cracking the Nut Section 12.2. What Good Is a cat?
Section 12.3. "less" is More
Section 12.4. Show Nonprinting Characters with cat -v or od -c Section 12.5. What's in That Whitespace?
Section 12.6. Finding File Types Section 12.7. Squash Extra Blank Lines
Section 12.8. How to Look at the End of a File: tail Section 12.9. Finer Control on tail
Section 12.10. How to Look at Files as They Grow Section 12.11. GNU tail File Following
Section 12.12. Printing the Top of a File Section 12.13. Numbering Lines
Chapter 13. Searching Through Files
Section 13.1. Different Versions of grep Section 13.2. Searching for Text with grep Section 13.3. Finding Text That Doesn't Match Section 13.4. Extended Searching for Text with egrep Section 13.5. grepping for a List of Patterns
Section 13.6. Approximate grep: agrep
Section 13.7. Search RCS Files with rcsgrep Section 13.8. GNU Context greps
Section 13.9. A Multiline Context grep Using sed Section 13.10. Compound Searches
Section 13.11. Narrowing a Search Quickly Section 13.12. Faking Case-Insensitive Searches Section 13.13. Finding a Character in a Column
Section 13.14. Fast Searches and Spelling Checks with "look"
Section 13.15. Finding Words Inside Binary Files Section 13.16. A Highlighting grep
Chapter 14. Removing Files
Section 14.1. The Cycle of Creation and Destruction Section 14.2. How Unix Keeps Track of Files: Inodes Section 14.3. rm and Its Dangers
Section 14.4. Tricks for Making rm Safer
Section 14.5. Answer "Yes" or "No" Forever with yes Section 14.6. Remove Some, Leave Some
Section 14.7. A Faster Way to Remove Files Interactively Section 14.8. Safer File Deletion in Some Directories Section 14.9. Safe Delete: Pros and Cons
Section 14.10. Deletion with Prejudice: rm -f Section 14.11. Deleting Files with Odd Names
Section 14.12. Using Wildcards to Delete Files with Strange Names Section 14.13. Handling a Filename Starting with a Dash (-) Section 14.14. Using unlink to Remove a File with a Strange Name Section 14.15. Removing a Strange File by its i-number
Section 14.16. Problems Deleting Directories Section 14.17. Deleting Stale Files
Section 14.18. Removing Every File but One
Section 14.19. Using find to Clear Out Unneeded Files
Chapter 15. Optimizing Disk Space
Section 15.1. Disk Space Is Cheap
Section 15.2. Instead of Removing a File, Empty It
Section 15.3. Save Space with "Bit Bucket" Log Files and Mailboxes Section 15.4. Save Space with a Link
Section 15.5. Limiting File Sizes
Section 15.6. Compressing Files to Save Space
Section 15.7. Save Space: tar and compress a Directory Tree Section 15.8. How Much Disk Space?
Section 15.9. Compressing a Directory Tree: Fine-Tuning Section 15.10. Save Space in Executable Files with strip Section 15.11. Disk Quotas
Part IV: Basic Editing
Chapter 16. Spell Checking, Word Counting, and Textual Analysis Section 16.1. The Unix spell Command
Section 16.2. Check Spelling Interactively with ispell Section 16.3. How Do I Spell That Word?
Section 16.4. Inside spell
Section 16.5. Adding Words to ispell's Dictionary
Section 16.6. Counting Lines, Words, and Characters: wc Section 16.7. Find a a Doubled Word
Section 16.8. Looking for Closure Section 16.9. Just the Words, Please
Chapter 17. vi Tips and Tricks
Section 17.1. The vi Editor: Why So Much Material?
Section 17.2. What We Cover
Section 17.3. Editing Multiple Files with vi Section 17.4. Edits Between Files
Section 17.5. Local Settings for vi
Section 17.6. Using Buffers to Move or Copy Text
Section 17.7. Get Back What You Deleted with Numbered Buffers Section 17.8. Using Search Patterns and Global Commands Section 17.9. Confirming Substitutions in vi
Section 17.10. Keep Your Original File, Write to a New File Section 17.11. Saving Part of a File
Section 17.12. Appending to an Existing File Section 17.13. Moving Blocks of Text by Patterns
Section 17.14. Useful Global Commands (with Pattern Matches) Section 17.15. Counting Occurrences; Stopping Search Wraps Section 17.16. Capitalizing Every Word on a Line
Section 17.17. Per-File Setups in Separate Files Section 17.18. Filtering Text Through a Unix Command
Section 17.19. vi File Recovery Versus Networked Filesystems Section 17.20. Be Careful with vi -r Recovered Buffers
Section 17.21. Shell Escapes: Running One UnixCommand While Using Another
Section 17.22. vi Compound Searches Section 17.23. vi Word Abbreviation
Section 17.24. Using vi Abbreviations as Commands (Cut and Paste Between vi's)
Section 17.25. Fixing Typos with vi Abbreviations
Section 17.26. vi Line Commands Versus Character Commands Section 17.27. Out of Temporary Space? Use Another Directory Section 17.28. Neatening Lines
Section 17.29. Finding Your Place with Undo Section 17.30. Setting Up vi with the .exrc File
Chapter 18. Creating Custom Commands in vi
Section 18.1. Why Type More Than You Have To?
Section 18.2. Save Time and Typing with the vi map Commands Section 18.3. What You Lose When You Use map!
Section 18.4. vi @-Functions
Section 18.5. Keymaps for Pasting into a Window Running vi Section 18.6. Protecting Keys from Interpretation by ex Section 18.7. Maps for Repeated Edits
Section 18.8. More Examples of Mapping Keys in vi Section 18.9. Repeating a vi Keymap
Section 18.10. Typing in Uppercase Without CAPS LOCK
Section 18.11. Text-Input Mode Cursor Motion with No Arrow Keys Section 18.12. Don't Lose Important Functions with vi Maps: Use
noremap
Section 18.13. vi Macro for Splitting Long Lines Section 18.14. File-Backup Macros
Chapter 19. GNU Emacs
Section 19.1. Emacs: The Other Editor Section 19.2. Emacs Features: A Laundry List
Section 19.3. Customizations and How to Avoid Them Section 19.4. Backup and Auto-Save Files
Section 19.5. Putting Emacs in Overwrite Mode Section 19.6. Command Completion
Section 19.7. Mike's Favorite Timesavers Section 19.8. Rational Searches
Section 19.9. Unset PWD Before Using Emacs Section 19.10. Inserting Binary Characters into Files Section 19.11. Using Word-Abbreviation Mode Section 19.12. Directories for Emacs Hacks Section 19.13. An Absurd Amusement
Chapter 20. Batch Editing
Section 20.1. Why Line Editors Aren't Dinosaurs Section 20.2. Writing Editing Scripts
Section 20.3. Line Addressing Section 20.4. Useful ex Commands
Section 20.5. Running Editing Scripts Within vi Section 20.6. Change Many Files by Editing Just One Section 20.7. ed/ex Batch Edits: A Typical Example
Section 20.8. Batch Editing Gotcha: Editors Fail on Big Files Section 20.9. patch: Generalized Updating of Files That Differ Section 20.10. Quick Reference: awk
Section 20.11. Versions of awk
Chapter 21. You Can't Quite Call This Editing Section 21.1. And Why Not?
Section 21.2. Neatening Text with fmt Section 21.3. Alternatives to fmt
Section 21.4. Clean Up Program Comment Blocks Section 21.5. Remove Mail/News Headers with behead Section 21.6. Low-Level File Butchery with dd
Section 21.7. offset: Indent Text Section 21.8. Centering Lines in a File
Section 21.9. Splitting Files at Fixed Points: split Section 21.10. Splitting Files by Context: csplit Section 21.11. Hacking on Characters with tr Section 21.12. Encoding "Binary" Files into ASCII Section 21.13. Text Conversion with dd
Section 21.14. Cutting Columns or Fields Section 21.15. Making Text in Columns with pr
Section 21.16. Make Columns Automatically with column Section 21.17. Straightening Jagged Columns
Section 21.18. Pasting Things in Columns Section 21.19. Joining Lines with join Section 21.20. What Is (or Isn't) Unique?
Section 21.21. Rotating Text
Chapter 22. Sorting
Section 22.1. Putting Things in Order Section 22.2. Sort Fields: How sort Sorts
Section 22.3. Changing the sort Field Delimiter
Section 22.4. Confusion with Whitespace Field Delimiters Section 22.5. Alphabetic and Numeric Sorting
Section 22.6. Miscellaneous sort Hints Section 22.7. lensort: Sort Lines by Length
Section 22.8. Sorting a List of People by Last Name
Part V: Processes and the Kernel Chapter 23. Job Control
Section 23.1. Job Control in a Nutshell Section 23.2. Job Control Basics Section 23.3. Using jobs Effectively
Section 23.4. Some Gotchas with Job Control
Section 23.5. The "Current Job" Isn't Always What You Expect Section 23.6. Job Control and autowrite: Real Timesavers!
Section 23.7. System Overloaded? Try Stopping Some Jobs Section 23.8. Notification When Jobs Change State
Section 23.9. Stop Background Output with stty tostop Section 23.10. nohup
Section 23.11. Disowning Processes Section 23.12. Linux Virtual Consoles
Section 23.13. Stopping Remote Login Sessions
Chapter 24. Starting, Stopping, and Killing Processes Section 24.1. What's in This Chapter
Section 24.2. fork and exec
Section 24.3. Managing Processes: Overall Concepts Section 24.4. Subshells
Section 24.5. The ps Command Section 24.6. The Controlling Terminal Section 24.7. Tracking Down Processes
Section 24.8. Why ps Prints Some Commands in Parentheses Section 24.9. The /proc Filesystem
Section 24.10. What Are Signals?
Section 24.11. Killing Foreground Jobs
Section 24.12. Destroying Processes with kill
Section 24.13. Printer Queue Watcher: A Restartable Daemon Shell Script
Section 24.14. Killing All Your Processes Section 24.15. Killing Processes by Name?
Section 24.16. Kill Processes Interactively
Section 24.17. Processes Out of Control? Just STOP Them Section 24.18. Cleaning Up an Unkillable Process
Section 24.19. Why You Can't Kill a Zombie
Section 24.20. The Process Chain to Your Window Section 24.21. Terminal Windows Without Shells
Section 24.22. Close a Window by Killing Its Process(es)
Chapter 25. Delayed Execution
Section 25.1. Building Software Robots the Easy Way Section 25.2. Periodic Program Execution: The cron Facility Section 25.3. Adding crontab Entries
Section 25.4. Including Standard Input Within a cron Entry
Section 25.5. The at Command
Section 25.6. Making Your at Jobs Quiet Section 25.7. Checking and Removing Jobs Section 25.8. Avoiding Other at and cron Jobs Section 25.9. Waiting a Little While: sleep
Chapter 26. System Performance and Profiling Section 26.1. Timing Is Everything Section 26.2. Timing Programs
Section 26.3. What Commands Are Running and How Long Do They Take?
Section 26.4. Checking System Load: uptime
Section 26.5. Know When to Be "nice" to Other Users...and When Not To
Section 26.6. A nice Gotcha
Section 26.7. Changing a Running Job's Niceness
Part VI: Scripting
Chapter 27. Shell Interpretation
Section 27.1. What the Shell Does
Section 27.2. How the Shell Executes Other Commands Section 27.3. What's a Shell, Anyway?
Section 27.4. Command Evaluation and Accidentally Overwriting Files Section 27.5. Output Command-Line Arguments One by One
Section 27.6. Controlling Shell Command Searches Section 27.7. Wildcards Inside Aliases
Section 27.8. eval: When You Need Another Chance Section 27.9. Which One Will bash Use?
Section 27.10. Which One Will the C Shell Use?
Section 27.11. Is It "2>&1 file" or "> file 2>&1"? Why?
Section 27.12. Bourne Shell Quoting
Section 27.13. Differences Between Bourne and C Shell Quoting Section 27.14. Quoting Special Characters in Filenames
Section 27.15. Verbose and Echo Settings Show Quoting Section 27.16. Here Documents
Section 27.17. "Special" Characters and Operators Section 27.18. How Many Backslashes?
Chapter 28. Saving Time on the Command Line
Section 28.1. What's Special About the Unix Command Line Section 28.2. Reprinting Your Command Line with CTRL-r Section 28.3. Use Wildcards to Create Files?
Section 28.4. Build Strings with { }
Section 28.5. String Editing (Colon) Operators Section 28.6. Automatic Completion
Section 28.7. Don't Match Useless Files in Filename Completion Section 28.8. Repeating Commands
Section 28.9. Repeating and Varying Commands
Section 28.10. Repeating a Command with Copy-and-Paste Section 28.11. Repeating a Time-Varying Command
Section 28.12. Multiline Commands, Secondary Prompts
Section 28.13. Here Document Example #1: Unformatted Form Letters Section 28.14. Command Substitution
Section 28.15. Handling Lots of Text with Temporary Files
Section 28.16. Separating Commands with Semicolons Section 28.17. Dealing with Too Many Arguments Section 28.18. Expect
Chapter 29. Custom Commands
Section 29.1. Creating Custom Commands Section 29.2. Introduction to Shell Aliases
Section 29.3. C-Shell Aliases with Command-Line Arguments Section 29.4. Setting and Unsetting Bourne-Type Aliases Section 29.5. Korn-Shell Aliases
Section 29.6. zsh Aliases
Section 29.7. Sourceable Scripts
Section 29.8. Avoiding C-Shell Alias Loops
Section 29.9. How to Put if-then-else in a C-Shell Alias
Section 29.10. Fix Quoting in csh Aliases with makealias and quote Section 29.11. Shell Function Basics
Section 29.12. Shell Function Specifics Section 29.13. Propagating Shell Functions
Section 29.14. Simulated Bourne Shell Functions and Aliases
Chapter 30. The Use of History
Section 30.1. The Lessons of History Section 30.2. History in a Nutshell Section 30.3. My Favorite Is !$
Section 30.4. My Favorite Is !:n*
Section 30.5. My Favorite Is ^^
Section 30.6. Using !$ for Safety with Wildcards Section 30.7. History by Number
Section 30.8. History Substitutions
Section 30.9. Repeating a Cycle of Commands
Section 30.10. Running a Series of Commands on a File Section 30.11. Check Your History First with :p
Section 30.12. Picking Up Where You Left Off Section 30.13. Pass History to Another Shell Section 30.14. Shell Command-Line Editing
Section 30.15. Changing History Characters with histchars Section 30.16. Instead of Changing History Characters
Chapter 31. Moving Around in a Hurry
Section 31.1. Getting Around the Filesystem
Section 31.2. Using Relative and Absolute Pathnames Section 31.3. What Good Is a Current Directory?
Section 31.4. How Does Unix Find Your Current Directory?
Section 31.5. Saving Time When You Change Directories: cdpath Section 31.6. Loop Control: break and continue
Section 31.7. The Shells' pushd and popd Commands Section 31.8. Nice Aliases for pushd
Section 31.9. Quick cds with Aliases Section 31.10. cd by Directory Initials
Section 31.11. Finding (Anyone's) Home Directory, Quickly Section 31.12. Marking Your Place with a Shell Variable
Section 31.13. Automatic Setup When You Enter/Exit a Directory
Chapter 32. Regular Expressions (Pattern Matching)
Section 32.1. That's an Expression
Section 32.2. Don't Confuse Regular Expressions with Wildcards Section 32.3. Understanding Expressions
Section 32.4. Using Metacharacters in Regular Expressions
Section 32.5. Regular Expressions: The Anchor Characters ^ and $ Section 32.6. Regular Expressions: Matching a Character with a
Character Set
Section 32.7. Regular Expressions: Match Any Character with . (Dot) Section 32.8. Regular Expressions: Specifying a Range of Characters
with [...]
Section 32.9. Regular Expressions: Exceptions in a Character Set Section 32.10. Regular Expressions: Repeating Character Sets with * Section 32.11. Regular Expressions: Matching a Specific Number of Sets
with \ { and \ }
Section 32.12. Regular Expressions: Matching Words with \ < and \ >
Section 32.13. Regular Expressions: Remembering Patterns with \ (, \ ), and \1
Section 32.14. Regular Expressions: Potential Problems Section 32.15. Extended Regular Expressions
Section 32.16. Getting Regular Expressions Right
Section 32.17. Just What Does a Regular Expression Match?
Section 32.18. Limiting the Extent of a Match Section 32.19. I Never Meta Character I Didn't Like
Section 32.20. Valid Metacharacters for Different Unix Programs Section 32.21. Pattern Matching Quick Reference with Examples
Chapter 33. Wildcards
Section 33.1. File-Naming Wildcards
Section 33.2. Filename Wildcards in a Nutshell Section 33.3. Who Handles Wildcards?
Section 33.4. What if a Wildcard Doesn't Match?
Section 33.5. Maybe You Shouldn't Use Wildcards in Pathnames Section 33.6. Getting a List of Matching Files with grep -l Section 33.7. Getting a List of Nonmatching Files
Section 33.8. nom: List Files That Don't Match a Wildcard
Chapter 34. The sed Stream Editor
Section 34.1. sed Sermon^H^H^H^H^H^HSummary Section 34.2. Two Things You Must Know About sed Section 34.3. Invoking sed
Section 34.4. Testing and Using a sed Script: checksed, runsed Section 34.5. sed Addressing Basics
Section 34.6. Order of Commands in a Script Section 34.7. One Thing at a Time
Section 34.8. Delimiting a Regular Expression Section 34.9. Newlines in a sed Replacement
Section 34.10. Referencing the Search String in a Replacement Section 34.11. Referencing Portions of a Search String
Section 34.12. Search and Replacement: One Match Among Many Section 34.13. Transformations on Text
Section 34.14. Hold Space: The Set-Aside Buffer Section 34.15. Transforming Part of a Line
Section 34.16. Making Edits Across Line Boundaries Section 34.17. The Deliberate Scrivener
Section 34.18. Searching for Patterns Split Across Lines
Section 34.19. Multiline Delete
Section 34.20. Making Edits Everywhere Except...
Section 34.21. The sed Test Command
Section 34.22. Uses of the sed Quit Command Section 34.23. Dangers of the sed Quit Command
Section 34.24. sed Newlines, Quoting, and Backslashes in a Shell Script
Chapter 35. Shell Programming for the Uninitiated Section 35.1. Writing a Simple Shell Program
Section 35.2. Everyone Should Learn Some Shell Programming Section 35.3. What Environment Variables Are Good For Section 35.4. Parent-Child Relationships
Section 35.5. Predefined Environment Variables Section 35.6. The PATH Environment Variable Section 35.7. PATH and path
Section 35.8. The DISPLAY Environment Variable Section 35.9. Shell Variables
Section 35.10. Test String Values with Bourne-Shell case Section 35.11. Pattern Matching in case Statements Section 35.12. Exit Status of Unix Processes
Section 35.13. Test Exit Status with the if Statement Section 35.14. Testing Your Success
Section 35.15. Loops That Test Exit Status Section 35.16. Set Exit Status of a Shell (Script) Section 35.17. Trapping Exits Caused by Interrupts Section 35.18. read: Reading from the Keyboard
Section 35.19. Shell Script "Wrappers" for awk, sed, etc.
Section 35.20. Handling Command-Line Arguments in Shell Scripts Section 35.21. Handling Command-Line Arguments with a for Loop Section 35.22. Handling Arguments with while and shift
Section 35.23. Loop Control: break and continue Section 35.24. Standard Command-Line Parsing Section 35.25. The Bourne Shell set Command Section 35.26. test: Testing Files and Strings Section 35.27. Picking a Name for a New Command
Section 35.28. Finding a Program Name and Giving Your Program Multiple Names
Section 35.29. Reading Files with the . and source Commands Section 35.30. Using Shell Functions in Shell Scripts
Chapter 36. Shell Programming for the Initiated Section 36.1. Beyond the Basics Section 36.2. The Story of : # #!
Section 36.3. Don't Need a Shell for Your Script? Don't Use One Section 36.4. Making #! Search the PATH
Section 36.5. The exec Command
Section 36.6. The Unappreciated Bourne Shell ":" Operator Section 36.7. Parameter Substitution
Section 36.8. Save Disk Space and Programming: Multiple Names for a Program
Section 36.9. Finding the Last Command-Line Argument Section 36.10. How to Unset All Command-Line Parameters Section 36.11. Standard Input to a for Loop
Section 36.12. Making a for Loop with Multiple Variables
Section 36.13. Using basename and dirname
Section 36.14. A while Loop with Several Loop Control Commands Section 36.15. Overview: Open Files and File Descriptors
Section 36.16. n>&m: Swap Standard Output and Standard Error
Section 36.17. A Shell Can Read a Script from Its Standard Input, but...
Section 36.18. Shell Scripts On-the-Fly from Standard Input
Section 36.19. Quoted hereis Document Terminators: sh Versus csh Section 36.20. Turn Off echo for "Secret" Answers
Section 36.21. Quick Reference: expr
Section 36.22. Testing Characters in a String with expr Section 36.23. Grabbing Parts of a String
Section 36.24. Nested Command Substitution
Section 36.25. Testing Two Strings with One case Statement Section 36.26. Outputting Text to an X Window
Section 36.27. Shell Lockfile
Chapter 37. Shell Script Debugging and Gotchas Section 37.1. Tips for Debugging Shell Scripts
Section 37.2. Bourne Shell Debugger Shows a Shell Variable Section 37.3. Stop Syntax Errors in Numeric Tests
Section 37.4. Stop Syntax Errors in String Tests Section 37.5. Quoting and Command-Line Parameters Section 37.6. How Unix Keeps Time
Section 37.7. Copy What You Do with script Section 37.8. Cleaning script Files
Section 37.9. Making an Arbitrary-Size File for Testing
Part VII: Extending and Managing Your Environment Chapter 38. Backing Up Files
Section 38.1. What Is This "Backup" Thing?
Section 38.2. tar in a Nutshell
Section 38.3. Make Your Own Backups Section 38.4. More Ways to Back Up
Section 38.5. How to Make Backups to a Local Device Section 38.6. Restoring Files from Tape with tar Section 38.7. Using tar to a Remote Tape Drive Section 38.8. Using GNU tar with a Remote Tape Drive Section 38.9. On-Demand Incremental Backups of a Project Section 38.10. Using Wildcards with tar
Section 38.11. Avoid Absolute Paths with tar
Section 38.12. Getting tar's Arguments in the Right Order Section 38.13. The cpio Tape Archiver
Section 38.14. Industrial Strength Backups
Chapter 39. Creating and Reading Archives Section 39.1. Packing Up and Moving
Section 39.2. Using tar to Create and Unpack Archives Section 39.3. GNU tar Sampler
Section 39.4. Managing and Sharing Files with RCS and CVS Section 39.5. RCS Basics
Section 39.6. List RCS Revision Numbers with rcsrevs Section 39.7. CVS Basics
Section 39.8. More CVS
Chapter 40. Software Installation
Section 40.1. /usr/bin and Other Software Directories
Section 40.2. The Challenges of Software Installation on Unix Section 40.3. Which make?
Section 40.4. Simplifying the make Process Section 40.5. Using Debian's dselect
Section 40.6. Installing Software with Debian's Apt-Get Section 40.7. Interruptable gets with wget
Section 40.8. The curl Application and One-Step GNU-Darwin Auto- Installer for OS X
Section 40.9. Installation with FreeBSD Ports Section 40.10. Installing with FreeBSD Packages
Section 40.11. Finding and Installing RPM Packaged Software
Chapter 41. Perl
Section 41.1. High-Octane Shell Scripting Section 41.2. Checking your Perl Installation Section 41.3. Compiling Perl from Scratch
Section 41.4. Perl Boot Camp, Part 1: Typical Script Anatomy Section 41.5. Perl Boot Camp, Part 2: Variables and Data Types Section 41.6. Perl Boot Camp, Part 3: Branching and Looping Section 41.7. Perl Boot Camp, Part 4: Pattern Matching Section 41.8. Perl Boot Camp, Part 5: Perl Knows Unix Section 41.9. Perl Boot Camp, Part 6: Modules
Section 41.10. Perl Boot Camp, Part 7: perldoc
Section 41.11. CPAN
Section 41.12. Make Custom grep Commands (etc.) with Perl Section 41.13. Perl and the Internet
Chapter 42. Python
Section 42.1. What Is Python?
Section 42.2. Installation and Distutils Section 42.3. Python Basics
Section 42.4. Python and the Web Section 42.5. urllib
Section 42.6. urllib2
Section 42.7. htmllib and HTMLParser
Section 42.8. cgi
Section 42.9. mod_python Section 42.10. What About Perl?
Part VIII: Communication and Connectivity Chapter 43. Redirecting Input and Output
Section 43.1. Using Standard Input and Output Section 43.2. One Argument with a cat Isn't Enough Section 43.3. Send (Only) Standard Error Down a Pipe Section 43.4. Problems Piping to a Pager
Section 43.5. Redirection in C Shell: Capture Errors, Too?
Section 43.6. Safe I/O Redirection with noclobber Section 43.7. The ( ) Subshell Operators
Section 43.8. Send Output Two or More Places
Section 43.9. How to tee Several Commands into One Place
Section 43.10. Redirecting Output to More Than One Place Section 43.11. Named Pipes: FIFOs
Section 43.12. What Can You Do with an Empty File?
Chapter 44. Devices
Section 44.1. Quick Introduction to Hardware Section 44.2. Reading Kernel Boot Output Section 44.3. Basic Kernel Configuration Section 44.4. Disk Partitioning
Section 44.5. Filesystem Types and /etc/fstab
Section 44.6. Mounting and Unmounting Removable Filesystems Section 44.7. Loopback Mounts
Section 44.8. Network Devices — ifconfig
Section 44.9. Mounting Network Filesystems — NFS, SMBFS Section 44.10. Win Is a Modem Not a Modem?
Section 44.11. Setting Up a Dialup PPP Session Section 44.12. USB Configuration
Section 44.13. Dealing with Sound Cards and Other Annoying Hardware Section 44.14. Decapitating Your Machine — Serial Consoles
Chapter 45. Printing
Section 45.1. Introduction to Printing
Section 45.2. Introduction to Printing on Unix Section 45.3. Printer Control with lpc
Section 45.4. Using Different Printers
Section 45.5. Using Symbolic Links for Spooling Section 45.6. Formatting Plain Text: pr
Section 45.7. Formatting Plain Text: enscript Section 45.8. Printing Over a Network Section 45.9. Printing Over Samba
Section 45.10. Introduction to Typesetting Section 45.11. A Bit of Unix Typesetting History Section 45.12. Typesetting Manpages: nroff
Section 45.13. Formatting Markup Languages — troff, LATEX, HTML, and So On
Section 45.14. Printing Languages — PostScript, PCL, DVI, PDF Section 45.15. Converting Text Files into a Printing Language Section 45.16. Converting Typeset Files into a Printing Language
Section 45.17. Converting Source Files Automagically Within the Spooler Section 45.18. The Common Unix Printing System (CUPS)
Section 45.19. The Portable Bitmap Package
Chapter 46. Connectivity
Section 46.1. TCP/IP — IP Addresses and Ports Section 46.2. /etc/services Is Your Friend Section 46.3. Status and Troubleshooting
Section 46.4. Where, Oh Where Did That Packet Go?
Section 46.5. The Director of Operations: inetd Section 46.6. Secure Shell (SSH)
Section 46.7. Configuring an Anonymous FTP Server Section 46.8. Mail — SMTP, POP, and IMAP
Section 46.9. Domain Name Service (DNS)
Section 46.10. Dynamic Host Configuration Protocol (DHCP) Section 46.11. Gateways and NAT
Section 46.12. Firewalls
Section 46.13. Gatewaying from a Personal LAN over a Modem
Chapter 47. Connecting to MS Windows Section 47.1. Building Bridges
Section 47.2. Installing and Configuring Samba Section 47.3. Securing Samba
Section 47.4. SWAT and GUI SMB Browsers Section 47.5. Printing with Samba
Section 47.6. Connecting to SMB Shares from Unix Section 47.7. Sharing Desktops with VNC
Section 47.8. Of Emulators and APIs
Section 47.9. Citrix: Making Windows Multiuser
Part IX: Security
Chapter 48. Security Basics
Section 48.1. Understanding Points of Vulnerability Section 48.2. CERT Security Checklists
Section 48.3. Keeping Up with Security Alerts Section 48.4. What We Mean by Buffer Overflow Section 48.5. What We Mean by DoS
Section 48.6. Beware of Sluggish Performance Section 48.7. Intruder Detection
Section 48.8. Importance of MOTD Section 48.9. The Linux proc Filesystem Section 48.10. Disabling inetd
Section 48.11. Disallow rlogin and rsh Section 48.12. TCP Wrappers
Chapter 49. Root, Group, and User Management Section 49.1. Unix User/Group Infrastructure Section 49.2. When Does a User Become a User Section 49.3. Forgetting the root Password Section 49.4. Setting an Exact umask
Section 49.5. Group Permissions in a Directory with the setgid Bit Section 49.6. Groups and Group Ownership
Section 49.7. Add Users to a Group to Deny Permissions Section 49.8. Care and Feeding of SUID and SGID Scripts Section 49.9. Substitute Identity with su
Section 49.10. Never Log In as root
Section 49.11. Providing Superpowers with sudo Section 49.12. Enabling Root in Darwin
Section 49.13. Disable logins
Chapter 50. File Security, Ownership, and Sharing
Section 50.1. Introduction to File Ownership and Security Section 50.2. Tutorial on File and Directory Permissions Section 50.3. Who Will Own a New File?
Section 50.4. Protecting Files with the Sticky Bit Section 50.5. Using chmod to Change File Permission Section 50.6. The Handy chmod = Operator
Section 50.7. Protect Important Files: Make Them Unwritable Section 50.8. cx, cw, c-w: Quick File Permission Changes
Section 50.9. A Loophole: Modifying Files Without Write Access Section 50.10. A Directory That People Can Access but Can't List Section 50.11. Juggling Permissions
Section 50.12. File Verification with md5sum
Section 50.13. Shell Scripts Must Be Readable and (Usually) Executable Section 50.14. Why Can't You Change File Ownership?
Section 50.15. How to Change File Ownership Without chown
Chapter 51. SSH
Section 51.1. Enabling Remote Access on Mac OS X Section 51.2. Protecting Access Through SSH Section 51.3. Free SSH with OpenSSH
Section 51.4. SSH Problems and Solutions
Section 51.5. General and Authentication Problems Section 51.6. Key and Agent Problems
Section 51.7. Server and Client Problems
Glossary
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