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)

Using Bash interactively

If Bash is your login shell, and you log in to the system from a terminal or terminal emulator, then it will start in interactive mode. In this mode, Bash will present a prompt when it's ready to accept a command from your terminal. This differs from non-interactive or batch mode, where commands are read from some other source, such as a script file. We will use interactive mode in this chapter to experiment with the basics of shell script command line grammar.

Nearly all of the features available to Bash in scripts are also available on the interactive command line, and they behave essentially the same way as if you ran them from a script. This allows you to treat the interactive command line as a live scripting environment: you can assign variables, create functions, and manage control flow and processes.

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