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

Editing output using sed


The sed command is a non-interactive stream editor that allows you to modify the content of the standard input or file. It performs an operation on each line in a pipeline. The syntax will be:

sed [OPTIONS]... {script} [input-file …]

By default, the output is displayed on stdout, but can be redirected to a file if specified.

The input-file are the files on which sed needs to be run. If no files are specified, it reads from stdin.

The script can be a command or a file with multiple commands to pass to sed, and OPTIONS to sed are described in the following table:

Option

Description

-n

This suppresses automatic printing of pattern space

-e script

This allows multiple scripts to be executed

-r

This uses the extended regex in the script

-l N

This specifies line wrap length

--posix

This disables all GNU extensions

-u

This loads the minimal amounts of data from input and flushes output buffers frequently

String substitution using s

The sed command is widely used...