Built-in functions are always available to the programmer for use in the program. This section covers the built-in functions in AWK. These functions generally accept arguments as input and return a value. Whitespace is ignored between the built-in function name and the opening parenthesis; however, we should avoid using whitespace in this way as user-defined functions do not permit whitespace.
If an expression is given as an argument to the function, the expression is evaluated before the call is made to the function. For example:
In the preceding case, p is incremented to the value of 6 before the sqrt function is called. It is good practice to evaluate the expression first and then pass the argument to the function.
