Book Image

Linux Shell Scripting Essentials

Book Image

Linux Shell Scripting Essentials

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

Filtering based on lines—head and tail


To display the content of a file, we will use the cat command. The cat command displays the whole file content on stdout. However, sometimes, we are interested in viewing only a few lines of a file. In this case, using cat will be tedious because we will have to scroll down to particular lines that we are interested in.

Shell provides us the head and tail commands to print only the lines in which we are interested in. The main difference between both the commands is, head prints the lines from the beginning of the files, and tail prints the lines from the end of the files.

Printing lines using head

The syntax is as follows:

head [OPTION] [FILE …]

By default, head prints first 10 lines of each FILE to stdout. If no file is mentioned or '-' is specified, the input is taken from stdin.

The options available in head can be used to change how much of the content to be printed. The options available are described in the following table:

Option

Description

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