GNU's Implementation of AWK – GAWK (GNU AWK)

This chapter covers the features of GNU AWK (GAWK) that are not available in primitive AWK. These features are not connected to each other, but are quite useful when used in the appropriate scenarios. Features such as reading non-decimal input, arbitrary precision arithmetic, array sorting, and some advance features such as network communication, debugging, and inter-process communication, are explained in this chapter using simple example programs. Some of these features are quite advanced, in the sense that their explanation requires a separate chapter devoted to them. However, we will discuss the main details of these features, so that we are able to use them when the situation arises. These features enhance the power of AWK and make it more productive.

In this chapter, we will cover the following :

• Reading non-decimal...

Things you don't know about GAWK

All features which are there in AWK are available as default in GAWK. In addition to these features, there are some other features of GAWK that essentially require a mention—they are covered in this section. These are not interrelated, so moving from one feature to another will be like picking up a random tool from a box filled with essential utilities.

Reading non-decimal input

The non-decimal values are like octal numbers or hexadecimal numbers. We cannot use these values to print their decimal equivalent with AWK; GAWK provides the option, --non-decimal-data, to print non-decimal values in the output. Octal values need to be prefixed with 0 and hexadecimal values need to be prefixed...

Summary

In this chapter, we learned about the features which are available in GAWK but not in AWK. We began with features such as handling non-decimal input, two-way inter-process communication, sorting of arrays, network programming and the GAWK built-in command line debugger. Finally, we learned about profiling using GAWK, for optimizing GAWK programs.

In our next chapter, we will cover some use case examples of text-processing using AWK for system administrators and programmers.