In this lesson we learn how to use the Linux wildcard. The wildcard allows you to automate what would otherwise be tedious tasks. The wildcard is the * character. For example, a command with *.txt would affect all files ending in .txt. Similarly, *.* would affect all files. You could also imagine dog*.txt would affect all files that start with “dog” and end with .txt. The video gives many examples of using the wildcard to simplify things.
In this tutorial we learn how to move, copy and delete files and folders in the Linux terminal window on the Raspberry Pi. These will allow you to start working with files and folders like a pro. Please watch the video above and follow along on your Raspberry Pi. It is really important that you become proficient at navigating the files from the terminal window and command line, and you know how to move, copy and delete files.
Windows is pretty forgiving in how you name your files and folders. In Linux, you must remember that things are case sensitive, and you want to avoid using spaces in your file names and folder names. Also remember, that in linux folders are also called directories. This video shows three suitable naming conventions in Linux that allow the files names to be both descriptive and readable.
As we learn more about the Raspberry Pi, we will get to the point that we will need to write programs. We have learned how to write python programs in our earlier tutorial series on the Arduino. Good news is that we can apply what we learned there to the Raspberry Pi. But, we will first have to learn how to create and edit text files. The text editor we will use on the Raspberry Pi is called “nano”. We will learn how to use nano by creating and editing simple text files. Also in this lesson we learn how to make new directories in Linux using the mkdir command. We also learn that we can view a file without opening it by using the “cat” command.
Watch the video above for all this information. These concepts are best taught and learned by watching and doing. So, watch the video and do the commands along with me. You will be an expert in no time!
The first thing we need to learn with Linux is how to navigate the file/folder structure in Linux. In windows we do this by just clicking on pictures of folders and files. The file structure in Linux operates the same way. We have a top level folder we call the root folder, and then we have folders and files inside of folders, and then those folders can have more folders and files. It is a tree type structure that you are already familiar with. What is different is we navigate through the files in Linux from the command lines, and not by clicking on pictures of windows and folders. Once you master the command line, you will prefer that to the clicking on pictures method of Windows.
In this lesson we will learn how to navigate through the files. In Linux, you first give the “waht”, that is what you want to do, or the command you want to do, and then you give the “where”, that is, where in the file structure you want to execute the command.
The first command we can learn is pwd. By typing pwd in the command line it will show you what folder you are presently in. That is useful as you are learning to navigate as it will always show you where you are.
The next command is ls. ls simply lists the files and folders in the present folder.
The final command covered in the video lesson above is cd, which stands for change directory.
After the command, you give the “where”, which is the path to where you want to do the command.
The method of navigating and understanding the file structure is easier to communicate by showing you, so please watch the video above. If you follow the video, you should clearly understand how the path methodology works in linux.