About this book

Here's where you'll find the code downloads and Discord channel

Community and Code Downloads

Organization of this book

Conventions used in this book

Development environment

Acknowledgements

About the author

Introduction

Find Bash Keyword, Function, and Builtin Command Documentation

How to Use man bash and help to Learn About Bash Commands

How to Find Information About Bash File Commands With --help

The Best References for Bash Commands

How to Find Package Specific Bash Documentation

How to Read a Synopsis and Understand Bash Documentation

How to Use apropos to Find Bash Commands (with examples)

Self–Help

How to Run a Bash Script Explicitly as an Argument in Terminal

How to Run a Bash Script With a Shebang Line and the Script Path

The Simplest Way to Run a Bash Script with $PATH

Running Scripts

How to Use Bash Readline to Edit Commands and Scripts

How to Edit Bash Scripts in Nano and Vim

Editing Commands and Scripts

Copying and Pasting

How to Select Text in Linux Terminal With a Mouse

How to Copy and Paste in Linux Terminal With Keyboard Shortcuts

How to Copy and Paste Text With the xclip Bash Command

How to Copy Formatted Text as HTML From Linux Terminal

How to Paste Text in Linux Terminal Safely

Listing Files

Using Linux ls Command to List Files and grep to Search for Files

How to Glob, Find Pattern Matching Files, and Run Commands

Text

How to Convert Windows Newlines For Bash With dos2unix

How to Convert Text to UTF-8 And Other Encodings in Bash Scripts

Math

How to Perform Arithmetic Expansion in Bash

How to Evaluate and Calculate Arithmetic Expressions in Bash

Best Practices for Using Variables in Bash Arithmetic

How to Write Conditional Expressions in Bash

Convert Bases in Bash to Work With Octals and Hexadecimals

How to Perform Floating Point Math With Bash bc

Time

Format Datetimes, Timestamps, and Time Zones in Bash

How to Time How Long a Bash Command Takes to Run

How to Kill Bash Commands With timeout

Output

How to Use the Bash Echo Command to Print Text in Terminal

printf vs echo - Printing Formatted Text With Newlines in Bash

Using the logger Command to Log Bash Output

JSON

How to Use jq Command to Filter JSON in Bash

\--stringparam username jdoe --stringparam password 'foo > bar'   
./authentication.xslt - &lt;&lt;&lt; '<x/>'
\```

Creating

Extracting an XML Value in Bash With xml_grep

Formatting and Transforming XML with XSLT

How to Create XML Files in Bash With xsltproc

Auto-Formatting

Images

How to Take Screenshots in Ubuntu Linux With Shortcuts and Bash

Resize, Convert, and Crop Pictures With ImageMagick mogrify

How to Create a Video From Images With ffmpeg

How to Create Graphs From Terminal With Graphviz

How to Remove and Edit Metadata From Photos With exif

Archiving and Compression

Beginner's Guide to tar Commands to Compress and Extract Files

Plain gzip

Other formats

How to Connect to an SSH Host Interactively

How to Create and Store SSH Keys in Bash

How to Execute Bash Scripts on Remote Server Non-Interactively

How to Access an SSH Server Behind a Jump Server

How to Exit SSH and Close a Hung Connection

From the Terminal to Production

The Portable Shebang Line to Run Bash Scripts Anywhere

How to Write Readable man Documentation For Your Bash Scripts

How to Build a Fail-Fast, Safe Bash Scripts

How to Check Shell Version From a Bash Script

How to Parse Bash Command Line Arguments

How to Include Files in Bash Command Line Arguments

How to Restrict Variable and Function Scope in Bash Scripts

Fail–Fast Settings

How to Exit Bash Script on Error With errexit

How to Prevent a Bash Script From Overwriting Files With noclobber

Make Bash Treat Undefined Variables as Errors With nounset

How to Set Bash pipefail to Add Exit Codes to Scripts

How to Fail a Bash Glob if it Returns no Files With failglob

Version Control

How to Start Using and Configure Git in Bash Terminal

How to Use Git in Bash Terminal to Push, Pull, and Commit Code

Git gud

Quality Assurance

The Beginner's Guide to Bash Linter

How to Test Bash Scripts

An Intro to Bash Signals: SIGINT, SIGKILL, SIGQUIT, and SIGTERM

How to Send Signals From Bash

How to Handle Signals and Errors in Bash Scripts

Signals

Autocompletion

How to Install Bash Autocompletions

How to Write an Autocompletion for a Bash Script

Summary

Changelog

Summary and Changelog

Bash is everywhere. It has grown to be the most popular shell on \*nixes – including Mac OS X and Windows Subsystem Linux (WSL). 

*The newline Guide to Bash Scripting* is an exploration of the Bash shell, scripting language and related tools. It’s aimed at developers who want to get the job done right the first time, and make sure maintenance is a breeze. Topics include:

- how to find help on arbitrary commands
- how to structure a robust and maintainable script
- editing commands and interacting with the terminal efficiently
- tools for dealing with version control, JSON, XML, text encodings, images and compressed files
- quality assurance
- … and much more

The goal of this book is to give you the tools and techniques to write Bash scripts which will stand the test of time, and to give you the means to explore the vast shell scripting ecosystem to find the tools you need right now.

### Audience

Bash is *the* Linux glue language, so this book is aimed at software developers mainly working in some other language. We assume that you have working knowledge of programming concepts like variable assignments, loops and files, and at least a passing familiarity with interactive shells.

If you're comfortable with web development, but not–so–comfortable on the commandline then this course is perfect for you.

Bash is the most popular shell and here we'll teach you popular tools, techniques, pitfalls and workarounds. Bash is simple to get started with, hard to master, and you can do incredible things with a line or two – inside we'll teach you how.

The newline Guide to Bash Scripting

How to create robust, maintainable scripts

The importance of error handling settings

Learn

The newline Guide to Building Your First GraphQL Server with Node and TypeScript

Teach

Amelia Wattenberger

Author of Fullstack D3

Community

Masterclasses

Tutorials

Fullstack React with TypeScript