Exercise 3 : Working with Directories

1. Open a shell as a normal user. Type cd. Next, type pwd, which stands for print working directory. You’ll see that you are currently in your home directory; that is, name /home/username.
   
   
2. Type touch file1. This command creates an empty file with the name file1 on your server. Because you currently are in your home directory, you can create any file you want to.
   
   
3. Type cd /. This changes the current directory to the root (/) directory. Type touch file2. You’ll see a “permission denied” message. Ordinary users can create files only in directories where they have the permissions needed for this.
   
   
4. Type cd /tmp. This brings you to the /tmp directory, where all users have write permissions. Again, type touch file2. You’ll see that you can create items in the /tmp directory (unless there is already a file2 that is owned by somebody else).
   
   
5. Type cd without any arguments. This command brings you back to your home directory.
   
   
6. Type mkdir files. This creates a directory with the name files in the current directory. The mkdir command uses the name of the directory that needs to be created as a relative pathname; it is relative to the position you are currently in.
   
   
7. Type mkdir /home/$USER/files. In this command, you are using the variable $USER, which is substituted with your current username. The complete argument of mkdir is an absolute filename to the directory files you are trying to create. Because this directory already exists, you’ll get a “file exists” error message.
   
   
8. Type rmdir files to remove the directory files you have just created. The rmdir command enables you to remove directories, but it works only if the directory is empty and does not contain any files.