Index

A

• alarm
  • generating / How to do it..., How it works...
• alias command / Adding aliases, and altering user paths/variables, How it works...
• aliases
  • adding / Adding aliases, and altering user paths/variables
• apt command / Getting ready
• arrays / How it works...
• artefact / Readying your script for different languages with internationalization
• artifact / Readying your script for different languages with internationalization
• ASCII / Basic searching for strings and files
• audio
  • playing / Playing and managing audio from Bash, How it works…
  • managing / Getting ready, How it works…
• AWK
  • used, for replacing substrings / Getting ready, How it works...

B

• Bash
  • fundamentals / Getting started with Bash and CLI fundamentals
  • about / Introduction
  • strings, managing / Striping/altering/sorting/deleting/searching strings with Bash only
  • battery life, monitoring / Getting ready
• Bash script
  • creating, with Vim / Your first Bash script with Vim
  • used, for monitoring udev input / Getting ready, How it works…
  • simple frontend GUIs, creating for / Getting ready, How to do it...
• Bash shell
  • compiling / Compiling and installing your own Bash shell, How it works...
  • installing / Compiling and installing your own Bash shell, How it works...
• basic loops
  • about / Basic loops
  • for loop / For loop
  • do while loop / Do while loop
• basic network connectivity
  • configuring / Configuring basic network connectivity, How to do it..., How it works...
• battery life
  • monitoring, Bash used / Getting ready
• binary
  • about / Formatting your data/output using echo and printf
  • dependencies, finding / Finding binary dependencies, How to do it..., How it works...
• binary numbers
  • evaluating / Evaluating binary numbers
• bzip2 / How it works...

C

• calculations
  • in scripts / Math and calculations in script, Getting ready, How to do it..., How it works...
• case statement
  • creating / Case/switch statements and loop constructs
  • about / Basic case statement
• cat command / How to do it…
• chroot
  • used, for securing scripts / Using chroot and restricted Bash shells to secure scripts, How it works…
• CLI
  • graphics, creating on / Getting ready, How it works...
  • presentations, creating on / Getting ready, How it works...
  • web, browsing from / Browsing the web from the CLI, How it works...
• command line colors / How to do it...
• command not found warnings/errors
  • avoiding / Avoiding command not found warnings/errors and improving portability, How it works...
• commands
  • linking / Linking commands, pipes, and input/output
  • about / Getting additional information about commands
  • invoking, on permission requirement / Invoking commands when they require permissions, Getting ready, How to do it..., How it works...
• Comma Separated Values (CSV) / Reading delimited data and altered output format
• conditional logic
  • using / Conditional logic using if, else, and elseif
  • file attributes, using with / Using file attributes with conditional logic, How to do it..., How it works...
• config file
  • creating / Creating a config file and using it in tandem with your scripts, How to do it...
  • using, in shell script / Creating a config file and using it in tandem with your scripts, How to do it...
• configuration
  • adding, to /etc/logrotate.d/ / Adding configuration to /etc/logrotate.d/
• connectivity diagnostics / Getting ready, How to do it..., How it works...
• Cron Jobs
  • creating / Creating and configuring cron Jobs for task scheduling
  • configuring / Creating and configuring cron Jobs for task scheduling
• crontab command / How it works...
• curl command / How it works…

D

• data
  • formatting, echo used / Formatting your data/output using echo and printf
  • formatting, printf used / Formatting your data/output using echo and printf
• datasets
  • generating / Generating datasets and random files of various size, Getting ready, How it works...
• date command / Fetching time from different locations
• dd command
  • using / Backing up and erasing media, disks, and partitions with DD
• delimited data
  • reading / Reading delimited data and altered output format, Getting ready, How to do it..., How it works...
• delimiters / Reading delimited data and altered output format
• dialog command / Creating graphics and presentations on the CLI
• diff
  • creating, of two files / Creating a diff of two files and patching, Getting ready, How to do it..., How it works...
• directories
  • monitoring / Monitoring directories and files, How it works...
• dmidecode tool / Gathering and aggregating system information
• DMZ firewall
  • creating / Creating a simple NAT and DMZ firewall, How it works…
• do while loop / Do while loop
• duplicate directories
  • finding / Finding and deleting duplicate files or directories, Getting ready
  • deleting / How to do it..., How it works...
• duplicate files
  • finding / Finding and deleting duplicate files or directories, Getting ready, How to do it...
  • deleting / How it works...
• duplicates
  • reducing, based on file contents / Calculating statistics and reducing duplicates based on file contents, How to do it..., How it works...

E

• echo
  • data, formatting / Formatting your data/output using echo and printf
  • output, formatting / Formatting your data/output using echo and printf
• elif statement / Conditional logic using if, else, and elseif
• ELinks / Browsing the web from the CLI
• else statement / Conditional logic using if, else, and elseif
• encoding scheme / Basic searching for strings and files
• escape character / Hidden Bash variables and reserved words
• evtest tool / Using Bash scripts to monitor udev input
• extension
  • files, searching by / Searching for files by name and/or extension, Getting ready, How to do it..., How it works...
• external functions
  • using / Including/importing a library script and using external functions

F

• failed SSH attempts
  • IP addresses, blocking from / Blocking IP addresses from failed SSH attempts, How it works…
• file-in-file-out program
  • creating / Creating a file-in-file-out program and running processes in parallel, How to do it..., How it works...
• file attributes
  • using, with conditional logic / Using file attributes with conditional logic, How to do it..., How it works...
• file descriptor
  • reference / Linking commands, pipes, and input/output
• file integrity
  • checking for / Checking for file integrity and tampering
• files
  • basic searching / Basic searching for strings and files, How to do it..., How it works...
  • viewing, from various angles / Viewing files from various angles – head, tail, less, and more, Getting ready, How to do it..., How it works...
  • searching, by name/extension / Searching for files by name and/or extension, Getting ready, How to do it..., How it works...
  • joining, at arbitrary positions / Joining and splitting files at arbitrary positions, Getting ready, How to do it..., How it works...
  • splitting, at arbitrary positions / Joining and splitting files at arbitrary positions, Getting ready, How to do it..., How it works...
  • generating, of multiple sizes / Generating datasets and random files of various size, Getting ready, How it works...
  • monitoring / Monitoring directories and files, How it works...
  • compressing / Compressing and archiving files, How to do it...
  • archiving / Compressing and archiving files, How to do it...
  • new configuration directives / Adding configuration to /etc/logrotate.d/
  • retrieving / Mounting network file systems and retrieving files, How it works...
  • encrypting, from script / Encrypting/decrypting files from a script
  • decrypting, from script / Encrypting/decrypting files from a script
  • collecting / Scraping the web and collecting files, How it works…
• filesystem directories
  • crawling / Crawling filesystem directories and printing a tree, How to do it..., How it works...
• firewall
  • Linux IPtables, using for / Using Linux iptables for a firewall, How to do it..., How it works...
• float / Creating and using basic variables
• for loop
  • about / For loop
  • functions, using with parameters / Using a function with parameters within a for loop
• format / Basic searching for strings and files
• functions
  • using / Using functions and parameters

G

• git command / Parsing a GitHub project and generate a report
• GitHub project
  • parsing / Parsing a GitHub project and generate a report, How it works…
• global context / Hidden Bash variables and reserved words
• globbing / Using wildcards and regexes
• graphics
  • creating, on CLI / Creating graphics and presentations on the CLI, How it works...
• grep command / Linking commands, pipes, and input/output, How it works..., How to do it…
• groups
  • creating / How to do it...

H

• head command / Viewing files from various angles – head, tail, less, and more
• headers
  • including / Including source files
• here-string / How it works...
• hexadecimal / Formatting your data/output using echo and printf
• hidden variables / Hidden Bash variables and reserved words
• high-quality scripts
  • writing / Writing high-quality scripts by example, How it works...
• HTTP GET method / How to do it…
• HTTP POST method / How to do it…
• hunk / How it works...

I

• if statement / Conditional logic using if, else, and elseif
• incremental remote backup
  • creating / Creating a poor man's incremental remote backup, How it works…
• inotify / Monitoring directories and files
• inotifywait command / How it works...
• integer / Creating and using basic variables
• integrated development editors (IDEs) / Getting started with Bash and CLI fundamentals
• internationalization
  • script, reading for languages / Readying your script for different languages with internationalization, Getting ready, How to do it..., How it works...
• inverted logic / How it works...
• IP addresses
  • blocking, from failed SSH attempts / Blocking IP addresses from failed SSH attempts, How it works…
• iptables / Using Linux iptables for a firewall
• iwconfig command / Linking commands, pipes, and input/output

J

• jobs / Getting ready

L

• lame utility HTTP server
  • creating / Creating a lame utility HTTP server, How to do it…, How it works…
• less command / Viewing files from various angles – head, tail, less, and more
• library script
  • including / Including/importing a library script and using external functions
  • importing / Including/importing a library script and using external functions
• Linux IPtables
  • using, for firewall / Using Linux iptables for a firewall, How to do it..., How it works...
• literal string / Creating and using basic variables
• log files
  • managing / How to do it..., How it works...
• logrotate command / Getting ready
• logs
  • files, rotating from RAM to storage / Rotating files from RAM to storage for log rotation
• loops
  • until loop / Until loop
  • writing / Writing one-line conditional statements and loops, How it works...
• Lorem Ipsum / How it works...
• ls command / Getting started with Bash and CLI fundamentals

M

• man command / Getting additional information about commands
• math
  • in scripts / Math and calculations in script, Getting ready, How to do it..., How it works...
• MD5sum / Finding and deleting duplicate files or directories
• media file
  • backing up / Backing up and erasing media, disks, and partitions with DD, How to do it...
  • erasing / Backing up and erasing media, disks, and partitions with DD
• more command / Viewing files from various angles – head, tail, less, and more
• mount command / Mounting network file systems and retrieving files, How to do it...

N

• name
  • files, searching by / Searching for files by name and/or extension, Getting ready, How to do it..., How it works...
• named pipes / How to do it...
• nested conditional statements / Nested if statements
• network file systems
  • mounting / Mounting network file systems and retrieving files, How it works...
• network information
  • gathering / Getting ready, How to do it..., How it works...
• network traffic
  • capturing, headlessly / Capturing network traffic headlessly, How to do it...

O

• one-line conditional statements
  • writing / Writing one-line conditional statements and loops, How it works...
• OpenSSL / How it works...
• output
  • retrieving / Retrieving return codes and output
  • echoing, to raw terminal devices / Echoing output to raw terminal devices, How to do it...
• output format
  • altering / Reading delimited data and altered output format, Getting ready, How to do it..., How it works...
• output HTML / How to do it…

P

• parameters
  • using / Using functions and parameters
• passwordless remote access
  • SSH keys, creating for / Creating SSH keys for password less remote access, How to do it...
• patch / Creating a diff of two files and patching
• patching / How to do it..., How it works...
• pattern / Basic searching for strings and files
• pipes / Redirection and pipe bonzanza, Creating a file-in-file-out program and running processes in parallel
• play command / How it works…
• portability
  • improving / Avoiding command not found warnings/errors and improving portability, How it works...
• presentations
  • creating, on CLI / Creating graphics and presentations on the CLI, How it works...
• printf
  • data, formatting / Formatting your data/output using echo and printf
  • output, formatting / Formatting your data/output using echo and printf
• processes
  • running, in parallel / Creating a file-in-file-out program and running processes in parallel, How to do it..., How it works...
• program flags
  • passing / Passing your program flags
• program input parameters
  • obtaining / Getting program input parameters 
• programs
  • keeping running, after logoff / Keeping programs/scripts running after logoff, Getting ready, How to do it..., How it works...
  • temporary files, using / Using temporary files and lock files in your program, Getting ready, How it works...
  • lock files, using / Using temporary files and lock files in your program, Getting ready, How it works...
• pwd command / Getting started with Bash and CLI fundamentals

R

• raw terminal devices
  • output, echoing to / Echoing output to raw terminal devices, How to do it...
• readarray command / How it works...
• recursive functionality / Introduction
• redirection / Redirection and pipe bonzanza
• regexes
  • using / Using wildcards and regexes, Getting ready, How to do it..., How it works...
  • reference / How it works...
• report
  • generating / Getting ready
• reserved words
  • about / Hidden Bash variables and reserved words
  • reference / Hidden Bash variables and reserved words
• restricted Bash shells
  • used, for securing scripts / Using chroot and restricted Bash shells to secure scripts, How it works…
• return codes
  • retrieving / Retrieving return codes and output
• return codes 101 / Return code 101
• root user / Getting started with Bash and CLI fundamentals
• RSS feeds
  • parsing / Parsing RSS feeds and output HTML

S

• scope / Creating and using basic variables
• scp command / How to do it...
• scripts
  • running, indefinitely / Running a program continuously (forever) using looping constructs or recursion, Getting ready, How to do it..., How it works...
  • keeping running, after logoff / Keeping programs/scripts running after logoff, Getting ready, How to do it..., How it works...
  • executing, on startup / Executing your script on startup, Getting ready, How to do it..., How it works...
  • files, encrypting from / Getting ready
  • files, decrypting from / Getting ready
  • securing, restricted Bash shells used / Using chroot and restricted Bash shells to secure scripts, How it works…
  • securing, chroot used / Using chroot and restricted Bash shells to secure scripts, How it works…
  • runtime, calculating / Calculating and reducing the runtime of a script, How it works...
  • runtime, reducing / Calculating and reducing the runtime of a script, How it works...
• Select
  • used, for making simple user menu / Making a simple multi-level user menu using select, How to do it..., How it works...
• SHA512sum / Finding and deleting duplicate files or directories
• shell
  • about / Getting started with Bash and CLI fundamentals
  • improving / Improving your shell – GCC and command line colors, How to do it..., How it works...
• shell script
  • about / Getting started with Bash and CLI fundamentals
  • config file, using in / Creating a config file and using it in tandem with your scripts, How to do it...
• SIGHUP / Generating and trapping signals for cleanup
• sign / How it works...
• signals
  • generating / Generating and trapping signals for cleanup, Getting ready, How it works...
  • trapping, for cleanup / Generating and trapping signals for cleanup, Getting ready, How it works...
• simple frontend GUIs
  • creating, for Bash scripts / Creating simple frontend GUIs for Bash scripts, How to do it...
• simple IRC chat bot logger
  • making / Making a simple IRC chat bot logger, How to do it…, How it works…
• simple NAT firewall
  • creating / Creating a simple NAT and DMZ firewall, How it works…
• source files
  • including / Including source files
• SoX / Playing and managing audio from Bash
• SQL databases
  • accessing, remotely / Accessing SQL databases remotely or locally, How it works...
  • accessing, locally / Getting ready, How it works...
• SSH keys
  • creating, for passwordless remote access / Creating SSH keys for password less remote access, How to do it...
• statistics
  • calculating / Calculating statistics and reducing duplicates based on file contents, How to do it..., How it works...
• stream editor (SED)
  • about / Using SED and AWK to remove/replace substrings
  • used, for removing substrings / Getting ready, How it works...
• strings
  • about / Creating and using basic variables
  • evaluating / Evaluating strings
  • basic searching / Basic searching for strings and files, How to do it..., How it works...
  • striping / Striping/altering/sorting/deleting/searching strings with Bash only, Getting ready, How to do it...
  • altering / Striping/altering/sorting/deleting/searching strings with Bash only, How to do it..., How it works...
  • sorting / Striping/altering/sorting/deleting/searching strings with Bash only, How to do it...
  • deleting / How to do it...
  • searching / How it works...
• substitute user do (Sudo) / Invoking commands when they require permissions
• substrings
  • removing, SED used / Getting ready, How it works...
  • replacing, AWK used / Getting ready, How it works...
• switch statement
  • creating / Case/switch statements and loop constructs
• symbolic links
  • creating / Creating symbolic links and using them effectively, How to do it...
  • using / How to do it..., How it works...
• Syslog entries
  • creating / Creating Syslog entries and generating an alarm  , How to do it..., How it works...
• system information
  • gathering / Gathering and aggregating system information, How to do it..., How it works...
  • aggregating / Gathering and aggregating system information, How to do it..., How it works...

T

• tail command / Linking commands, pipes, and input/output, Viewing files from various angles – head, tail, less, and more
• tampering
  • checking for / Checking for file integrity and tampering
• TAR file / How it works...
• tcpdump / Capturing network traffic headlessly
• terminal / Getting started with Bash and CLI fundamentals
• terminal sessions
  • recording, for automation / Recording terminal sessions for automation, How it works...
• time
  • fetching, from different locations / Fetching time from different locations, How it works...
• time command / Calculating and reducing the runtime of a script, How to do it...
• timeout
  • leveraging, on wait for command completion / Leveraging timeout when waiting for command completion, How to do it..., How it works...
• TLP / Using Bash to monitor battery life and optimize it, How it works…
• tree
  • printing / Crawling filesystem directories and printing a tree, How to do it..., How it works...
• ttyrec tool / Recording terminal sessions for automation

U

• udev input
  • monitoring, Bash scripts used / Using Bash scripts to monitor udev input, How it works…
• until loop / Until loop
• useradd command / How to do it...
• user input
  • sanitizing / Sanitizing user input and for repeatable results, Getting ready, How to do it..., How it works...
• user menu
  • making, Select used / Making a simple multi-level user menu using select, How to do it..., How it works...
• user paths
  • altering / Adding aliases, and altering user paths/variables
• users
  • creating / Creating users and groups systematically
• UTF / Basic searching for strings and files

V

• variable assignment / Hands-on variable assignment
• variables
  • creating / Creating and using basic variables
  • using / Creating and using basic variables
  • hidden variables / Hidden Bash variables and reserved words
  • altering / Adding aliases, and altering user paths/variables
• Vim
  • Bash script, creating / Your first Bash script with Vim
  • reference / Your first Bash script with Vim

W

• W3M / Browsing the web from the CLI
• web
  • browsing, from CLI / Browsing the web from the CLI, How it works...
  • scraping / Scraping the web and collecting files, How it works…
• wget utility / How it works…
• whoami command / Getting started with Bash and CLI fundamentals
• wildcards
  • using / Using wildcards and regexes, Getting ready, How to do it..., How it works...
• wpa_supplicant / Configuring basic network connectivity

Z

• zenity tool
  • about / Creating simple frontend GUIs for Bash scripts
  • working / How it works...
• zip / How it works...