Being Linux based, the tiny Single Board Computer Raspberry Pi or RBPi has a graphical user interface familiar to regular computer users. Again, as most users of Linux will be familiar with, RBPi also has a command line interface where you have to type in the commands you want the SBC to execute. Well, a graphical user interface does have its merits and although the command line interface is a little more intimidating to the uninitiated, it is not a very difficult beast to tame.
One of the major advantages of the command line interface is its scope and speed – it easily accomplishes and most often surpasses what can be achieved with the graphical user interface, and does it faster as well. For most day-to-day tasks, however, the graphical interface is enough and has many useful applications including a web browser, test editor and file manager.
For those who want to delve deeper and learn more about how the SBC actually works, the command line interface is the way to go. Most of the work is done by opening up a Terminal or Shell and typing within it.
As the name suggests, the command line interface is an entirely text-based interface. You type in the commands that you want the SBC to execute, and it gives you a response. Although in the beginning, it will seem a little confusing, it is more like interacting in a natural way, just as we converse with another person. Once mastered, interacting with a computer via the command line interface will let you learn much more about it in the future.
You begin by opening up a Virtual Terminal/Console. Why is the name Terminal used? This is a legacy from the past when computers were gargantuan beasts, centrally located, with remote terminals distributed to the users. When you click on the LXTerminal on the Raspbian desktop, a small bordered box opens up, with ‘pi@raspberrypi $’ written inside it. The box is the terminal and inside it is the command prompt. The command prompt shows the name of the user – ‘pi’, the name of the computer – ‘raspberry’, also called the domain name, and the ‘$’ signifies that pi is a regular user and not the root or superuser (for root, the prompt would change to ‘#’).
The command prompt shows that your RBPi is now ready and waiting for you to type in your command. For example, you can see where you are by asking the computer to Print the Working Directory, by entering ‘pwd’ and hitting Enter. The SBC will most likely return – ‘/home/pi’, unless you have changed your username.
You can change the directory with ‘cd ..’, the computer knows that it has to return to the parent directory – ‘/home’. You may verify this with another ‘pwd’. With the command List Files or ‘ls’, you will be able to see all the files residing in the directory. Use a flag ‘-a’, to list the hidden files or all the files in the directory. Now the command becomes ‘ls -a’. Use ‘ls -l’ to see more information about the files.
For more information and for learning the command line, visit the website linuxcommand.org