Book Image

Mastering Linux Shell Scripting

By : Andrew Mallett
Book Image

Mastering Linux Shell Scripting

By: Andrew Mallett

Overview of this book

Shell scripting is a quick method to prototype a complex application or a problem by automating tasks when working on Linux-based systems. Using both simple one-line commands and command sequences complex problems can be solved with ease, from text processing to backing up sysadmin tools. In this book, you’ll discover everything you need to know to master shell scripting and make informed choices about the elements you employ. Get to grips with the fundamentals of creating and running a script in normal mode, and in debug mode. Learn about various conditional statements' code snippets, and realize the power of repetition and loops in your shell script. Implement functions and edit files using the Stream Editor, script in Perl, program in Python – as well as complete coverage of other scripting languages to ensure you can choose the best tool for your project.
Table of Contents (16 chapters)
15
Index

Abbreviations

We have already taken one short sojourn into the ~/.vimrc file and we will now revisit this file to look at abbreviations or abbr controls. This file acts as the run control mechanism for the vim text editor, which is likely to be installed on your Linux distribution. Older distributions or Unix variants may have the original vi text editor and will make use of the ~/.exrc file. If you are uncertain of the identity of your version of vi and the correct run control file to use, simply, enter the vi command. If a blank page opens, it is indeed vi. However, if a new blank document opens with the vim splash screens, then you are using the improved vim or Vi.

Abbreviations allow for a shortcut string to be used in place of a longer string. These abbreviations can be set during a vim session from the last line mode but are often set in the control file. The shebang can be easily represented by an abbreviation, as follows:

abbr _sh #!/bin/bash

The basic syntax of an abbreviation is...