Summary

In this chapter, we learned about different types of built-in and user-defined functions that accept zero or more arguments and return a value. Function arguments can be made up of expressions that are evaluated before calling a function. We began by looking at built-in functions such as arithmetic functions, which are used for numeric processing. We followed this up by looking at string functions that are used for string manipulations and for matching the occurrences of a pattern in a string. Then, we looked at various input/output functions, such as the close() function for closing files and pipes. After this, we looked at the time functions, which can be quite useful when it comes to timestamping or creating log files. We followed this by bit-manipulation functions, which perform bitwise operations on two or more integers. Finally, we looked at how to define and call...