Oswald Campesato - Bash Command Line and Shell Scripts

BASH COMMAND LINE AND SHELL SCRIPTS

POCKET PRIMER

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BASH COMMAND LINE AND SHELL SCRIPTS

POCKET PRIMER

Oswald Campesato

MERCURY LEARNING AND INFORMATION

Dulles, Virginia

Boston, Massachusetts

New Delhi

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O. Campesato. Bash Command Line and Shell Scripts Pocket Primer.

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Id like to dedicate this book to my parents may this bring joy and happiness into their lives.

The goal of this book is to introduce readers to an assortment of powerful command line utilities that can be combined to create simple, yet powerful shell scripts. While all examples and scripts use the bash command set, many of the concepts translate into other command shells (such as sh, ksh, zsh, and csh), including the concept of piping data between commands, regular expression substitution, and the sed and awk commands. Aimed at a reader relatively new to working in a bash environment, the book is comprehensive enough to be a good reference and teach a few new tricks to those who already have some experience with creating shells scripts.

This short book contains a variety of code fragments and shell scripts for data scientists, data analysts, and other people who want shell-based solutions to clean various types of text files. In addition, the concepts and code samples in this book are useful for people who want to simplify routine tasks.

This book takes introductory concepts and commands in bash, and then demonstrates their use in simple yet powerful shell scripts. This book does not cover pure system administration functionality for Unix or Linux.

This book is intended for general users, data scientists, data analysts, and other people who perform a variety of tasks from the command line, and who also have a limited knowledge of shell programming.

You will acquire an understanding of how to use various bash commands, often as part of short shell scripts. The chapters also contain simple use cases that illustrate how to perform various tasks involving text files, such as switching the order of a two-column text file, removing control characters in a text file, find specific lines and merge them, reformatting a date field in a text file, and removing nested quotes.

This book saves you the time required to search for relevant code samples, adapting them to your specific needs, which is a potentially time-consuming process.

The code samples in this book were created and tested using bash on a Macbook Pro with OS X 10.12.6 (macOS Sierra). The code samples are derived primarily from scripts prepared by the author, and in some cases there are code samples that incorporate short sections of code from discussions in online forums. The key point to remember is that the code samples follow the Four Cs: they must be Clear, Concise, Complete, and Correct to the extent that its possible to do so, given the page length of this book.