Lesson 4: Use the Command Line

Question 1

What are some advantages of using the command-line interface?

Answer 1

The command-line interface provides these advantages:

• Additional administrative and troubleshooting options
• More access to the file system
• A remote login using the Secure Shell (SSH) protocol
• Any administrator can run commands as the system administrator user or root, using sudo
• The ability to automate repetitive tasks using scripting
• The ability to remotely administer multiple, even thousands, of Mac computers simultaneously using Apple Remote Desktop
• The documentation found in man pages provides an explanation of command usage and references to other related commands

Question 2

What are the four parts of a command string?

Answer 2

The four parts of a command string are as follows:

Example: ls -lah ~/ > ~/Desktop/homeDirectoryList.txt

1. Command name
   
   • ls to “list directory contents”
2. Command options
   
   • -l to “List in long format”
   • -a to “Include directory entries whose names begin with a dot (.)”
   • -h to “When used with the -l option, use unit suffixes: Byte, Kilobyte, Megabyte, Gigabyte, Terabyte and Petabyte in order to reduce the number of digits to three or less using base 2 for sizes.”
3. Arguments
   
   • ~/ the current user’s home directory is the target of action
4. Extras
   
   • > ~/Desktop/homeDirectoryList.txt redirect the output of the ls command to a new file on the user’s Desktop called “homeDirectoryList.txt.”

Question 3

Which terminal command should you use to perform the following tasks?

• Print working directory
• List
• Change directory
• Indicate parent directory
• Indicate current user home folder
• Create a folder
• Run the command with root account access
• Clear the Terminal screen
• Use the Spotlight index to find a file

Answer 3

Use these commands to perform the following tasks:

• Print working directory: pwd
• List: ls
• Change directory: cd
• Indicate parent directory: ..
• Indicate current user home folder: ~
• Create a folder: mkdir
• Run the command with root account access: sudo
• Clear the Terminal screen: clear or press <kbd>Control-L</kbd>
• You can search for files with the Spotlight index using mdfind

Question 4

Which key should you use if you want to automatically complete filenames, pathnames, and command names?

Answer 4

You should use the <kbd>Tab</kbd> key to automatically complete filenames, pathnames, and command names.

Question 5

What is the new default shell interpreter in macOS Catalina?

Answer 5

The Z shell (zsh) is now the default shell, but the bash shell is still installed in macOS Catalina.