13.3. Understanding Shell Scripts

This section explains how more advanced shell scripts work. The information is also adequate to equip you to write many of your own useful shell scripts. The section begins by showing how to process a script's arguments. Then it shows how to perform conditional and iterative operations.

13.3.1. Processing Arguments

You can easily write scripts that process arguments, because a set of special shell variables holds the values of arguments specified when your script is invoked. Table 13.10 describes the most popular such shell variables.