Introduction

The shell scripting language is packed with all the essential problem-solving components for Unix/Linux systems. Text processing is one of the key areas where shell scripting is used, and there are beautiful utilities such as sed, awk, grep, and cut, which can be combined to solve problems related to text processing.

Various utilities help to process a file in fine detail of a character, line, word, column, row, and so on, allowing us to manipulate a text file in many ways. Regular expressions are the core of pattern-matching techniques, and most of the text-processing utilities come with support for it. By using suitable regular expression strings, we can produce the desired output, such as filtering, stripping, replacing, and searching.

This chapter includes a collection of recipes, which walk through many contexts of problems based on text processing that will be helpful in writing real scripts.