Book Image

Linux Shell Scripting Essentials

By : Sinny Kumari, Khem Raj
Book Image

Linux Shell Scripting Essentials

By: Sinny Kumari, Khem Raj

Overview of this book

Table of Contents (15 chapters)
Linux Shell Scripting Essentials
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Alias


Alias in shell refers to giving another name to a command or group of commands. It is very useful when a name of a command is long. With the help of alias, we can avoid typing a bigger name and invoke a command by a name as per your convenience.

To create an alias, alias shell builtin command is used. The syntax is as follows:

alias alias_name="Commands to be aliased"

Creating alias

To print a disk space in a human-readable format, we use the df command with the -h option. By making alias of df -h to df, we can avoid typing again and again df -h.

The output of the df command before aliasing it to df -h is shown in the following screenshot:

$ df

Now, to create alias for df -h to df, we will execute the following command:

$ alias df="df -h"	# Creating alias
$ df

The output obtained is as follows:

We see that after creating alias of df -h to df, a default disk space is printed in a human-readable format.

Another useful example can be aliasing the rm command to rm -i. Using rm with the -i option...