Book Image

Linux Shell Scripting Cookbook, Second Edition - Second Edition

Book Image

Linux Shell Scripting Cookbook, Second Edition - Second Edition

Overview of this book

The shell remains one of the most powerful tools on a computer system — yet a large number of users are unaware of how much one can accomplish with it. Using a combination of simple commands, we will see how to solve complex problems in day to day computer usage.Linux Shell Scripting Cookbook, Second Edition will take you through useful real-world recipes designed to make your daily life easy when working with the shell. The book shows the reader how to effectively use the shell to accomplish complex tasks with ease.The book discusses basics of using the shell, general commands and proceeds to show the reader how to use them to perform complex tasks with ease.Starting with the basics of the shell, we will learn simple commands with their usages allowing us to perform operations on files of different kind. The book then proceeds to explain text processing, web interaction and concludes with backups, monitoring and other sysadmin tasks.Linux Shell Scripting Cookbook, Second Edition serves as an excellent guide to solving day to day problems using the shell and few powerful commands together to create solutions.
Table of Contents (16 chapters)
Linux Shell Scripting Cookbook
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Monitoring disk usage


Disk space is a limited resource. We frequently perform disk usage calculation on storage media (such as hard disks) to find out the free space available on them. When free space becomes scarce, we find out large files to be deleted or moved in order to create free space. In addition to this, disk usage manipulations are also used in shell scripting contexts. This recipe will illustrate various commands used for disk manipulations with a variety of options.

Getting ready

df and du are the two significant commands that are used for calculating disk usage in Linux. The command df stands for disk free and du stands for disk usage. Let's see how we can use them to perform various tasks that involve disk usage calculation.

How to do it...

To find the disk space used by a file (or files), use:

$ du  FILENAME1 FILENAME2 ..

For example:

$ du file.txt
4

Note

The result is, by default, shown as size in bytes.

To obtain the disk usage for all files inside a directory along with the...