Fundamentals of Linux

Understanding regular expressions

In this section, we will introduce the wonderful art of regular expressions. You will learn what they are and why they are so powerful. There are a lot of different regular expression characters available, and here we will introduce the most important ones. Afterward, you will learn how to apply regular expressions with the grep command to find, extract, and filter useful information out of text files. Regular expressions, or regexps for short, are a very powerful concept used to search through text using special patterns, describing the structure of the search term instead of a constant string of characters, which is also called literal text search in this context. Using regular expressions can save you ...