Using the command line, environment variables, and navigating through the filesystem
As we have seen before, once we log in to the system, we have access to the command line. It's important to navigate the command line and the filesystem well in order to feel comfortable in the environment and make the most of it.
Command line and environment variables
The command line is provided by a program also known as interpreter or shell. It will behave differently depending on which shell we use, but in this section, we will cover the most widespread shell used in Linux and the one provided by default in RHEL: bash.
A simple trick to know which shell you are using is to run the following command:
[root@rhel8 ~]# echo $SHELL /bin/bash
The echo command will show on screen the content of whatever we give to it. Some content needs to be substituted or interpreted, like environment variables. The content to be substituted starts with the $ symbol. In this case, we are telling...
