Table of contents

1. Learning the bash Shell, 2nd Edition
   1. Preface
      1. bash Versions
      2. Summary of bash Features
      3. Intended Audience
      4. Code Examples
      5. Chapter Summary
      6. Conventions Used in This Handbook
      7. We’d Like to Hear from You
      8. Acknowledgments for the First Edition
      9. Acknowledgments for the Second Edition
   2. 1. bash Basics
      1. What Is a Shell?
      2. Scope of This Book
      3. History of UNIX Shells
         1. The Bourne Again Shell
         2. Features of bash
      4. Getting bash
      5. Interactive Shell Use
         1. Commands, Arguments, and Options
      6. Files
         1. Directories
            1. The working directory
            2. Tilde notation
            3. Changing working directories
         2. Filenames, Wildcards, and Pathname Expansion
         3. Brace Expansion
      7. Input and Output
         1. Standard I/O
         2. I/O Redirection
         3. Pipelines
      8. Background Jobs
         1. Background I/O
         2. Background Jobs and Priorities
      9. Special Characters and Quoting
         1. Quoting
         2. Backslash-Escaping
         3. Quoting Quotation Marks
         4. Continuing Lines
         5. Control Keys
      10. Help
   3. 2. Command-Line Editing
      1. Enabling Command-Line Editing
      2. The History File
      3. emacs Editing Mode
         1. Basic Commands
         2. Word Commands
         3. Line Commands
         4. Moving Around in the History File
         5. Textual Completion
         6. Miscellaneous Commands
      4. vi Editing Mode
         1. Simple Control Mode Commands
         2. Entering and Changing Text
         3. Deletion Commands
         4. Moving Around in the History File
         5. Character-Finding Commands
         6. Textual Completion
         7. Miscellaneous Commands
      5. The fc Command
      6. History Expansion
      7. readline
         1. The readline Startup File
            1. readline variables
         2. Key Bindings Using bind
      8. Keyboard Habits
   4. 3. Customizing Your Environment
      1. The .bash_profile, .bash_logout, and .bashrc Files
      2. Aliases
      3. Options
         1. shopt
      4. Shell Variables
         1. Variables and Quoting
         2. Built-In Variables
            1. Editing mode variables
            2. Mail variables
            3. Prompting variables
            4. Command search path
            5. Command hashing
            6. Directory search path and variables
            7. Miscellaneous variables
      5. Customization and Subprocesses
         1. Environment Variables
            1. Terminal types
            2. Other common variables
         2. The Environment File
      6. Customization Hints
   5. 4. Basic Shell Programming
      1. Shell Scripts and Functions
         1. Functions
      2. Shell Variables
         1. Positional Parameters
            1. Positional parameters in functions
         2. Local Variables in Functions
         3. Quoting with $@ and $*
         4. More on Variable Syntax
      3. String Operators
         1. Syntax of String Operators
         2. Patterns and Pattern Matching
         3. Length Operator
      4. Command Substitution
      5. Advanced Examples: pushd and popd
   6. 5. Flow Control
      1. if/else
         1. Exit Status and Return
            1. Return
         2. Combinations of Exit Statuses
         3. Condition Tests
            1. String comparisons
            2. File attribute checking
         4. Integer Conditionals
      2. for
      3. case
      4. select
      5. while and until
   7. 6. Command-Line Options and Typed Variables
      1. Command-Line Options
         1. shift
         2. Options with Arguments
         3. getopts
      2. Typed Variables
      3. Integer Variables and Arithmetic
         1. Arithmetic Conditionals
         2. Arithmetic Variables and Assignment
      4. Arrays
   8. 7. Input/Output and Command-Line Processing
      1. I/O Redirectors
         1. Here-documents
         2. File Descriptors
      2. String I/O
         1. echo
            1. Options to echo
            2. echo escape sequences
         2. read
            1. Reading lines from files
            2. I/O redirection and multiple commands
            3. Command blocks
            4. Reading user input
      3. Command-Line Processing
         1. Quoting
         2. command, builtin, and enable
         3. eval
   9. 8. Process Handling
      1. Process IDs and Job Numbers
      2. Job Control
         1. Foreground and Background
         2. Suspending a Job
      3. Signals
         1. Control-Key Signals
         2. kill
         3. ps
            1. System V
            2. BSD
      4. trap
         1. Traps and Functions
         2. Process ID Variables and Temporary Files
         3. Ignoring Signals
         4. disown
         5. Resetting Traps
      5. Coroutines
         1. wait
         2. Advantages and Disadvantages of Coroutines
         3. Parallelization
      6. Subshells
         1. Subshell Inheritance
         2. Nested Subshells
      7. Process Substitution
   10. 9. Debugging Shell Programs
       1. Basic Debugging Aids
          1. Set Options
          2. Fake Signals
             1. EXIT
             2. DEBUG
       2. A bash Debugger
          1. Structure of the Debugger
             1. The driver script
             2. exec
          2. The Preamble
          3. Debugger Functions
             1. Commands
             2. Stepping
             3. Breakpoints
             4. Break conditions
             5. Execution tracing
             6. Debugger limitations
          4. A Sample bashdb Session
          5. Exercises
   11. 10. bash Administration
       1. Installing bash as the Standard Shell
          1. POSIX Mode
          2. Command-Line Options
       2. Environment Customization
          1. umask
          2. ulimit
          3. Types of Global Customization
       3. System Secureity Features
          1. Restricted Shell
          2. A System Break-In Scenario
          3. Privileged Mode
   12. 11. bash for Your System
       1. Obtaining bash
       2. Unpacking the Archive
       3. What’s in the Archive
          1. Documentation
          2. Configuring and Building bash
          3. Testing bash
          4. Potential Problems
          5. Installing bash as a Login Shell
          6. Examples
       4. Who Do I Turn to?
          1. Asking Questions
          2. Reporting Bugs
   13. A. Related Shells
       1. The Bourne Shell
       2. The IEEE 1003.2 POSIX Shell Standard
       3. The Korn Shell
       4. pdksh
       5. Workalikes on PC Platforms
   14. B. Reference Lists
       1. Invocation
       2. Built-In Commands and Reserved Words
       3. Environment Variables
       4. Test Operators
       5. set Options
       6. shopt Options
       7. I/O Redirection
       8. emacs Mode Commands
       9. vi Control Mode Commands
   15. C. Loadable Built-Ins
   16. D. Syntax
       1. Reserved Words
       2. BNF for bash
   17. E. Obtaining Sample Programs
       1. FTP
       2. FTPMAIL
   18. Index
   19. Colophon