Homework: Unix CLI Practice

Class: SEI
Creator: Thom Page
Modified by: Kristyn Bryan and Reuben Ayres
Topics: Terminal, boolean expressions, reading code, while loops, for loops

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Section 1: Terminal Practice

Episode X: A New Terminal

A long time ago in a Unix environment far, far away, young Jedi padawans who knew only of desktop software were seduced by the dark side of the Force to enter… The Terminal.

Follow the instructions below using all the console commands introduced in Fundamentals, class, or that you find on your own.

Setup

• Open the Terminal app

• Create a new directory in your sei/fundamentals directory called star_wars.

• Create a file called commands.txt.

• Paste the answer to each numbered question (i.e. the command(s) that accomplished the task) in commands.txt once you get it to work.

• Remember, you can learn about any Unix command by typing man and then the command name. E.g., man ls. Type Q to get out of the Manual page ("man page") viewer.

Part I: Set the Scene

Complete all work inside the star_wars folder.

1. Create a directory called death_star, and make the following files inside of it: darth_vader.txt, princess_leia.txt, storm_trooper.txt

2. In a directory galaxy_far_far_away, make a directory named tatooine and create the following files in it: luke.txt, ben_kenobi.txt.

3. Inside of tatooine make a directory called millenium_falcon, and in it create: han_solo.txt, chewbaca.txt

Part II: mv - rename

• You can rename a file using the mv command.

4. Rename ben_kenobi.txt to obi_wan.txt.

Part II: cp - copy

• You can copy a file from one location to another using the cp command. (man cp for more info)

• Directories can be sibling (parrell to each other) or can be parents (the folder that contains the folder you are in)

5. Copy storm_trooper.txt from death_star to tatooine.

Part IV: mv - move

• You can use the mv command to move files from one location to another. mv can be used for renaming, moving, or both. Run man mv to see the options—remember hit the Q key to get out of the manual page viewer.

6. Move luke.txt and obi_wan.txt to the millenium_falcon.

7. Move millenium_falcon out of tatooine and into galaxy_far_far_away.

8. Move millenium_falcon into death_star.

9. Move princess_leia.txt into the millenium_falcon.

Part V: rm - remove

BE CAREFUL WITH rm!!! THERE IS NO "TRASH" IN THE UNIX CLI. WHEN YOU DELETE SOMETHING IT IS GONE FOREVER!!!

You can use rm to delete a file.

10. Delete obi_wan.txt.

Part VI: all together

11. In galaxy_far_far_away, make a directory called yavin_4.

12. Move the millenium_falcon out of the death_star and into yavin_4.

13. Make a directory in yavin_4 called x_wing.

14. Move princess_leia.txt to yavin_4 and luke.txt to x_wing.

15. Move the millenium_falcon and x_wing out of yavin_4 and into galaxy_far_far_away.

16. In death_star, create directories for tie_fighter_1, tie_fighter_2 and tie_fighter_3.

17. Move darth_vader.txt into tie_fighter_1.

18. Make a copy of storm_trooper.txt in both tie_fighter_2 and tie_fighter_3.

19. Move all of the tie_fighters out of the death_star and into galaxy_far_far_away.

Part VII: rm -r: remove directories and everything they contain

BE CAREFUL WITH rm!!! THERE IS NO TRASH CAN IN THE UNIX CLI. WHEN YOU DELETE SOMETHING IT IS GONE FOREVER

Before you hit enter, make sure are deleting the right thing, or you could accidentally delete the contents of your computer (it has happened).

This command will not typically ask you if you "really want to delete." It will just delete.

20. Remove tie_fighter_2 and tie_fighter_3.

Part VIII:

21. Touch a file in x_wing called the_force.txt.

22. Destroy the death_star and anyone inside of it.

23. Return x_wing and the millenium_falcon to yavin_4.

Celebrate. You've reached the end of section 1 :)

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🔴 Commit and push your updated code:

"Add" your changes (prepare them to be "committed"):

$ git add -A

"Commit" your changes—any time you make a commit, you can always restore the files in the repo to that point:

$ git commit -m "Completed homework assignment"

"Push" your commits to github:

$ git push origin master

"Hungry for more?"

Want an extra challenge? In many assignments or labs, you'll find a "Hungry for More" section which is designed for further learning. If they seem too overwhelming you can absolutely skip them. They won't factor into your homework score, and you will be totally fine for class as long as you complete and understand the main assignment up to that point. What they will do is encourage you to go deeper, explore, and push yourself. And that will pay off big time in the long run. Below is the "hungry for more" section for this assignment.

Try to complete the following, making a commit after each one.

...as long as you don't mess up the homework assignment you just did. They get more difficult/complex as you go (more or less).

• Create a directory called test-dir with a couple files in it. Try to make a copy of that entire directory. (Hint: man cp for more info.)

• Find and use command line shortcuts.

• Try applying one command to multiple files at once.

• Try applying one command to all files in a single directory (where necessery)

• Try applying one command to all files that match a pattern.

• Try using a mix of absolute and relative paths.

• If you're a glutton for punishment, read about the famous text editor "vi" online. It's included with all Unix systems, and although it has a steep learning curve, it is an incredibly powerful text editor. You can run a tutorial program that will teach you some vi/vim commands by typing vimtutor in your Terminal. See if you can use it to create and edit a small "Hello, World!" JavaScript program!

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Homework submission

When you've got your homework all done, just send a Slack message to your instructor. Going forward, we will be submitting homework using a "pull request" process in git. Your instructor will show you the submission process tomorrow afternoon.