A function, also known as a named procedure, is a set of instructions that is used by programming languages to return a single result or a set of results. The statement that requests the function is called a function call. The functions extend the usefulness and functionality of AWK. This chapter covers the different types of built-in functions that are available in AWK. The built-in functions of AWK are generally divided into three categories, namely numeric, string, and I/O. Apart from these, we will cover the additional functions provided by GAWK to represent time, to provide type information, and to enable bit manipulation. Then, we will discuss how AWK is used for writing user-defined functions for use in the rest of the program.
In this chapter, we will cover the following topics:
- Arithmetic functions
- String functions
- Input/output functions
- Time functions ...
