Book Image

Learning AWK Programming

By : Shiwang Kalkhanda
5 (1)
Book Image

Learning AWK Programming

5 (1)
By: Shiwang Kalkhanda

Overview of this book

AWK is one of the most primitive and powerful utilities which exists in all Unix and Unix-like distributions. It is used as a command-line utility when performing a basic text-processing operation, and as programming language when dealing with complex text-processing and mining tasks. With this book, you will have the required expertise to practice advanced AWK programming in real-life examples. The book starts off with an introduction to AWK essentials. You will then be introduced to regular expressions, AWK variables and constants, arrays and AWK functions and more. The book then delves deeper into more complex tasks, such as printing formatted output in AWK, control flow statements, GNU's implementation of AWK covering the advanced features of GNU AWK, such as network communication, debugging, and inter-process communication in the GAWK programming language which is not easily possible with AWK. By the end of this book, the reader will have worked on the practical implementation of text processing and pattern matching using AWK to perform routine tasks.
Table of Contents (11 chapters)

Summary

In this chapter, we learned to use print() and printf() for finer control over output. We began with OFS and ORS for formatting the output, which was followed by introduction to escape sequences in printf for printing special characters. Then we learned how AWK uses format-control characters for different data types, and optional modifiers for modifying the behavior of format control characters. Finally, we covered how the output from both print and printf can be redirected to files and pipes. In the end, we learned the importance of the close() function to close open files and pipes.

In the next chapter, we will learn about different types of expressions in AWK programming language and how they form the core logic of a program.