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Linux and Unix Shell Programming
book

Linux and Unix Shell Programming

by David Tansley
December 1999
Beginner
528 pages
11h 10m
English
Pearson Business
Content preview from Linux and Unix Shell Programming

14.1. What is a shell variable?

Variables let you customize your working environment. You use variables to hold information that you want to use yourself, to let the system know more about you. Variables are also used to hold constant information. For instance, there is a variable called EDITOR. Now there are not that many editors around, but which is your favourite? Assign this name to the EDITOR variable, and that’s what you’ll use all the time if you use cron or other applications that require you to use an editor. The system looks for the value held in the variable EDITOR, and will use that as your default editor.

Here’s an example. Our audit system has logs that need to be edited. When I select this option from the menu, the application ...

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ISBN: 0201674726Purchase book