Book Image

Bash Quick Start Guide

By : Tom Ryder
Book Image

Bash Quick Start Guide

By: Tom Ryder

Overview of this book

Bash and shell script programming is central to using Linux, but it has many peculiar properties that are hard to understand and unfamiliar to many programmers, with a lot of misleading and even risky information online. Bash Quick Start Guide tackles these problems head on, and shows you the best practices of shell script programming. This book teaches effective shell script programming with Bash, and is ideal for people who may have used its command line but never really learned it in depth. This book will show you how even simple programming constructs in the shell can speed up and automate any kind of daily command-line work. For people who need to use the command line regularly in their daily work, this book provides practical advice for using the command-line shell beyond merely typing or copy-pasting commands into the shell. Readers will learn techniques suitable for automating processes and controlling processes, on both servers and workstations, whether for single command lines or long and complex scripts. The book even includes information on configuring your own shell environment to suit your workflow, and provides a running start for interpreting Bash scripts written by others.
Table of Contents (10 chapters)


The third method of creating your own commands with Bash is to put them in a script: a file that you can arrange for bash to interpret and execute from the filesystem by name.

What a "script" means to Bash can mean many different things depending on context. In this book, we'll focus on scripts stored as executable program files on our filesystem, external to the Bash process itself.

Scripting methods

There are three general ways to run a script file in Bash: sourcing it, providing it to bash as input, and as a standalone script. For the following examples, we'll use the hello.bash script, with the following contents:

printf 'Hello, %s!\n' "$USER"

Sourcing the script means to...