You are likely to be familiar with using a search and replace dialog (usually invoked with the Ctrl+H shortcut) to locate the occurrences of a particular string and replace it with something else. The sed command is a versatile and feature-rich version for search and replace operations, usable from the command line. An important feature that GUI applications may lack is regular expressions, a mini-programming language to precisely define a matching criteria.

This book heavily leans on examples to present features one by one. In addition to command options, regular expressions will also be discussed in detail.

Exercises are also included to test your understanding.

Prerequisites

You should be familiar with command line usage in a Unix-like environment. You should also be comfortable with concepts like file redirection and command pipelines. Knowing the basics of the grep command will be handy in understanding the filtering features of sed.

You are also expected to get comfortable with reading manuals, searching online, visiting external links provided for further reading, tinkering with illustrated examples, asking for help when you are stuck and so on. In other words, be proactive and curious instead of just consuming the content passively.

If you are new to the world of the command line, check out my Computing from the Command Line ebook and curated resources on Linux CLI and Shell scripting before starting this book.