Cover -- Title Page -- Copyright -- Dedication -- Contents -- Preface -- Chapter 1: Introduction -- Unix Versus Linux -- Available Shell Types -- What is bash? -- Getting Help for bash Commands -- Navigating Around Directories -- The history Command -- Listing Filenames with the ls Command -- Displaying the Contents of Files -- The cat Command -- The head and tail Commands -- The Pipe Symbol -- The fold Command -- File Ownership: Owner, Group, and World -- Hidden Files -- Handling Problematic Filenames -- Working with Environment Variables -- The env Command -- Useful Environment Variables -- Setting the PATH Environment Variable -- Specifying Aliases and Environment Variables -- Finding Executable Files -- The printf Command and the echo Command -- The cut Command -- The echo Command and Whitespaces -- Command Substitution (Backtick) -- The Pipe Symbol and Multiple Commands -- Using a Semicolon to Separate Commands -- The paste Command -- Inserting Blank Lines with the paste Command -- A Simple Use Case with the paste Command -- A Simple Use Case with cut and paste Commands -- Working with Metacharacters -- Working with Character Classes -- Working with "^" and "\" and "!" -- What about zsh? -- Switching between bash and zsh -- Configuring zsh -- Summary -- Chapter 2: Files and Directories -- Create, Copy, Remove, and Move Files -- Creating Text Files -- Copying Files -- Copy Files with Command Substitution -- Deleting Files -- Moving Files -- The ln Command -- The basename, dirname, and file Commands -- The wc Command -- The cat Command -- The more Command and the less Command -- The head Command -- The tail Command -- Comparing File Contents -- The Parts of a Filename -- Working with File Permissions -- The chmod Command -- Changing Owner, Permissions, and Groups -- The umask and ulimit Commands -- Working with Directories.

Absolute and Relative Directories -- Absolute/Relative Pathnames -- Creating Directories -- Removing Directories -- Navigating to Directories -- Moving Directories -- Using Quote Characters -- Streams and Redirection Commands -- Metacharacters and Character Classes -- Digits and Characters -- Filenames and Metacharacters -- Summary -- Chapter 3: Useful Commands -- The join Command -- The fold Command -- The split Command -- The sort Command -- The uniq Command -- How to Compare Files -- The od Command -- The tr Command -- A Simple Use Case -- The find Command -- The tee Command -- File Compression Commands -- The tar command -- The cpio Command -- The gzip and gunzip Commands -- The bunzip2 Command -- The zip Command -- Commands for zip Files and bz Files -- Internal Field Separator (IFS) -- Data from a Range of Columns in a Dataset -- Working with Uneven Rows in Datasets -- Summary -- Chapter 4: Conditional Logic and Loops -- Quick Overview of Operators in bash -- Arithmetic Operations and Operators -- The expr Command -- Arithmetic Operators -- Boolean and Numeric Operators -- Compound Operators and Numeric Operators -- Working with Variables -- Assigning Values to Variables -- The read Command for User Input -- Boolean Operators and String Operators -- Compound Operators and String Operators -- File Test Operators -- Compound Operators and File Operators -- Conditional Logic with if/else/fi Statements -- The case/esac Statement -- Working with Strings in Shell Scripts -- Working with Loops -- Using a for Loop -- Checking Files in a Directory -- Working with Nested Loops -- Using a while Loop -- The while, case, and if/elif/else/fi Statements -- Using an until Loop -- User-defined Functions -- Creating a Simple Menu from Shell Commands -- Arrays in bash -- Working with Arrays -- Summary -- Chapter 5: Filtering Data with grep.

What is the grep Command? -- Metacharacters and the grep Command -- Escaping Metacharacters with the grep Command -- Useful Options for the grep Command -- Character Classes and the grep Command -- Working with the -c Option in grep -- Matching a Range of Lines -- Using Back References in the grep Command -- Finding Empty Lines in Datasets -- Using Keys to Search Datasets -- The Backslash Character and the grep Command -- Multiple Matches in the grep Command -- The grep Command and the xargs Command -- Searching zip Files for a String -- Checking for a Unique Key Value -- Redirecting Error Messages -- The egrep Command and fgrep Command -- Displaying "Pure" Words in a Dataset with egrep -- The fgrep Command -- A Simple Use Case -- Summary -- Chapter 6: Transforming Data with sed -- What Is the sed Command? -- The sed Execution Cycle -- Matching String Patterns Using sed -- Substituting String Patterns Using sed -- Replacing Vowels from a String or a File -- Deleting Multiple Digits and Letters from a String -- Search and Replace with sed -- Datasets with Multiple Delimiters -- Useful Switches in sed -- Working with Datasets -- Printing Lines -- Character Classes and sed -- Removing Control Characters -- Counting Words in a Dataset -- Back References in sed -- Displaying Only "Pure" Words in a Dataset -- One-Line sed Commands -- Summary -- Chapter 7: Doing Everything Else with awk -- The awk Command -- Built-in Variables that Control awk -- How Does the awk Command Work? -- Aligning Text with the printf() Command -- Conditional Logic and Control Statements -- The while Statement -- A for Loop in awk -- A for Loop with a break Statement -- The next and continue Statements -- Deleting Alternate Lines in Datasets -- Merging Lines in Datasets -- Printing File Contents as a Single Line -- Joining Groups of Lines in a Text File.

Joining Alternate Lines in a Text File -- Matching with Metacharacters and Character Sets -- Printing Lines Using Conditional Logic -- Splitting Filenames with awk -- Working with Postfix Arithmetic Operators -- Numeric Functions in awk -- One-line awk Commands -- Useful Short awk Scripts -- Printing the Words in a Text String in awk -- Count Occurrences of a String in Specific Rows -- Printing a String in a Fixed Number of Columns -- Printing a Dataset in a Fixed Number of Columns -- Aligning Columns in Datasets -- Aligning Columns and Multiple Rows in Datasets -- Removing a Column from a Text File -- Subsets of Column-aligned Rows in Datasets -- Counting Word Frequency in Datasets -- Displaying Only "Pure" Words in a Dataset -- Working with Multi-line Records in awk -- A Simple Use Case -- Another Use Case -- Summary -- Chapter 8: Introduction to Shell Scripts and Functions -- What are Shell Scripts? -- A Simple Shell Script -- Setting Environment Variables via Shell Scripts -- Sourcing or "Dotting" a Shell Script -- Working with Functions in Shell Scripts -- Passing Values to Functions in a Shell Script (1) -- Passing Values to Functions in a Shell Script (2) -- Iterate Through Values Passed to a Function -- Positional Parameters in User-defined Functions -- Shell Scripts, Functions, and User Input -- Recursion and Shell Scripts -- Iterative Solutions for Factorial Values -- Calculating Fibonacci Numbers -- Calculating the GCD of Two Positive Integers -- Calculating the LCM of Two Positive Integers -- Calculating Prime Divisors -- Summary -- Chapter 9: Shell Scripts with the grep and awk Commands -- The grep Command -- Simulating Relational Data with the grep Command -- Checking Updates in a Logfile -- Processing Multi-line Records -- Adding the Contents of Records -- Using the split Function in awk -- Scanning Diagonal Elements in Datasets.

Adding Values From Multiple Datasets (1) -- Adding Values from Multiple Datasets (2) -- Adding Values from Multiple Datasets (3) -- Calculating Combinations of Field Values -- Summary -- Chapter 10: Miscellaneous Shell Scripts -- Using rm and mv with Directories -- Using the find Command with Directories -- Creating a Directory of Directories -- Cloning a Set of Subdirectories -- Executing Files in Multiple Directories -- The case/esac Command -- Compressing and Uncompressing Files -- The dd Command -- The crontab Command -- Uncompressing Files as a cron Job -- Scheduled Commands and Background Processes -- How to Schedule Tasks -- The nohup Command -- Executing Commands Remotely -- How to Schedule Tasks in the Background -- How to Terminate Processes -- Terminating Multiple Processes -- Process-Related Commands -- How to Monitor Processes -- Checking Execution Results -- System Messages and Log Files -- Disk Usage Commands -- Trapping and Ignoring Signals -- Arithmetic with the bc and dc Commands -- Working with the date Command -- Print-related Commands -- Creating a Report with the printf() Command -- Checking Updates in a Logfile -- Listing Active Users on a Machine -- Miscellaneous Commands -- Summary -- Index.