Pipes and subshells are one way of expanding the capabilities of our shell. The ultimate way is by writing shell scripts. These scenarios must be taken into consideration when dealing with complex tasks that can't be automated with a one-line command.
The good news is that almost all the tasks can be automated with the use of shell scripts. We won't go over an introduction to shell scripts. Instead, we will be looking at some more advanced use cases for writing them.
Let's start our journey into shell scripting! First thing, let's open a file called script.sh and split the screen so that we can test while writing. Every shell should start with #!, followed by the interpreter it uses. This line is called a shebang. We will be using bash as our default interpreter.
It's a good idea to use bash, because it's a common interpreter that comes with most Linux distributions and also OS X:
#!/bin/bash
Let's start with a simple use case: reading the arguments passed...