sed (stream editor) is a non-interactive command-line text editor. sed is commonly used to filter text, i.e., it takes text input, performs some operation (or set of operations) on it, and outputs the modified text. sed is typically used for extracting part of a file using pattern matching or substituting multiple occurrences of a string within a file.

The sed Reference Manual provides beginners with a simple introduction to the basics, and experts will find advanced details they need.

In this you will see the following things below.

Table of Contents

sed, a stream editor
1 Introduction
2 Invocation
3 sed Programs
3.1 How sed Works
3.2 Selecting lines with sed
3.3 Overview of Regular Expression Syntax
3.4 Often-Used Commands
3.5 The s Command
3.6 Less Frequently-Used Commands
3.7 Commands for sed gurus
3.8 Commands Specific to GNU sed
3.9 GNU Extensions for Escapes in Regular Expressions
4 Some Sample Scripts
4.1 Centering Lines
4.2 Increment a Number
4.3 Rename Files to Lower Case
4.4 Print bash Environment
4.5 Reverse Characters of Lines
4.6 Reverse Lines of Files
4.7 Numbering Lines
4.8 Numbering Non-blank Lines
4.9 Counting Characters
4.10 Counting Words
4.11 Counting Lines
4.12 Printing the First Lines
4.13 Printing the Last Lines
4.14 Make Duplicate Lines Unique
4.15 Print Duplicated Lines of Input
4.16 Remove All Duplicated Lines
4.17 Squeezing Blank Lines
5 GNU sed's Limitations and Non-limitations
6 Other Resources for Learning About sed
7 Reporting Bugs
Appendix A Extended regular expressions
Concept Index
Command and Option Index

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