Code tacoma command_line
- 1. Code Tacoma: Command Line Basics Andrea Urban September 8, 2018 Please sit next to someone with an operating system similar to yours.
- 2. Agenda 1. Installation and Set up: 15 minutes 2. Introductions 3. Introduction to the Command Line 4. Basic Commands
- 3. Installation and Setup Mac/unix/linux: Open terminal Windows: 3 options ● If you want to be a developer, but not interested in python (fastest install): Install Git Tools for Windows from the following URL: https://git-scm.com/download/win. When prompted in the installation wizard, select: "Use Git and optional Unix tools for the Windows Command Prompt". Open the git bash. ● If you want to learn python too: Install anaconda https://conda.io/docs/user-guide/install/windows.html. Don't do miniconda; do the full anaconda installer. Choose Python 3.6. Open the anaconda prompt and type ‘conda create -n main m2-base’. Say y to all queries. When Install is complete type “conda activate main” (To practice command line commands in future, you’ll need to type last command every time you reopen conda prompt. ● Big installation (not recommended): Install cygwin https://www.cygwin.com/ (a virtual unix machine for windows). I would not recommend this option because it's a really large program. However, if it's already installed, then you're ready. When you’re ready: Compare your screen to your neighbor’s. Check with another neighbor.
- 4. Ground Rules If you have any trouble sounding condescending, find a UNIX user to show you how it's done. — Scott Adams, Dilbert Cartoonist ● Don’t act like a “UNIX user”. ● Mission: Learn UNIX tools and help others learn them too.
- 5. Introductions Who am I? ● Andrea Urban ● Data scientist ● I mostly work in Python and SQL in Windows. In a past life, I used a Unix machine coding in Fortran. Who are you? ● Name ● Why are you interested in learning command line? ● Do you know any programming languages?
- 6. CLI: Command Line Interface A text interface for interacting with a computer.
- 7. GUI: Graphical User Interface Use mouse to interact with computer. Drag windows and files around.
- 8. CLI: Command Line Interface GUI: Graphical User Interface
- 9. Why is it useful to learn the command line? Bulk actions - Ex: Delete all the jpg’s in a folder Connecting to remote servers Many remote servers only allow you to connect via a terminal. Remote server interface gui could be slow compared to terminal. Any other reasons?
- 11. The prompt What do you see in your terminal? Puffy-Cloud:~ Andrea$ ● Puffy-Cloud = my computer’s name ● ~ = where I am located in my file system ● Andrea = my user name What your prompt may look like… > $ Any others?
- 12. pwd: Where are we? > pwd What do you see? pwd = print working directory Tells you where you are in your file system.
- 13. cd: Take me home. “cd” stands for “Change Directories” > cd Take me to my home directory ~ : refers to home directory (> cd ~ also takes user home) (Joke: There is no place like ~) What output do you see? > cd .. Take me up a directory What output do you see? How can you check if this worked?
- 14. cd: Take me home. “cd” stands for “Change Directories” > cd > cd ../.. Take me up two directories Be sure to check your work. Self-check: How do I go home? How do I go up three directories?
- 15. ls: Take a look around > cd First go back home. ls stands for “list” contents > ls List current directory’s contents What do you see? > ls .. Lists contents of directory above current directory Now what do you see?
- 16. ls: Take a look around > cd > ls -l Show long format of contents of directory > man ls Show manual pages for the ls command. Use arrow keys to navigate. Useful for learning about new flags (-l is a flag) Use the man pages to find out what ls -l is showing you.
- 17. Self-check What will you see if you try the following command? Take a guess before typing it in the terminal > ls ../.. How can I print out the file size in human-readable format, i.e., 3.5K instead of 3536 bytes? (Hint: take a look at the man page for ls)
- 18. Hidden Files > cd > ls -a List ALL the contents of the current directory, including hidden files Hidden files generally start with a period “.” The hidden files: “.” and “..” represent the current and parent directory What do you expect to happen when you type ”ls .” ?
- 20. mkdir: Build something new Make a directory > cd > mkdir workshop > ls workshop What does this last command do? Now, go into the new directory.
- 21. touch: Building another new thing touch let’s you create new empty files easily > cd workshop > pwd Output: ~/workshop Make sure you are in the directory that you just created. > ls Verify that directory is empty > touch this > touch that > touch other Now what’s inside the directory?
- 22. Searching smart Wildcards can be used in the command line. > ls t* Only list files starting with the letter t. > ls *r Only list files ending with the letter r.
- 23. Self-check Only list files containing the letter “i” Make another directory inside the workshop directory called “pets” Put two new files in the directory called “cat” and “dog” Check your work with a neighbor.
- 24. Did you accidentally put the cat and dog files in the workshop directory instead of the pets directory?
- 25. rm: proceed with caution (You know it’s serious when there’s a Star Wars gif.)
- 26. rm: proceed with caution rm : remove file(s) There is NO undo button or command for rm The most dangerous command rm *
- 27. rm: Cleaning up mistakes Go to the workshop directory. Create files “cat” and “dog” in this directory (unless they are already there). > pwd (should be “workshop”) > touch cat > touch dog > ls (Verify that cat and dog are new files) > rm cat > ls (Verify that cat is now gone) > rm dog > ls (Verify that dog is now gone)
- 28. rmdir: remove directory rmdir is rm for directories. Directories must be empty. > cd > cd workshop > rmdir pets (will delete if directory is empty, otherwise keep going) > cd pets > rm * > cd .. > rmdir pets > ls pets directory should be gone
- 29. > and >> (not the prompt) > ls > files.txt Takes output of ls command and stores it in the file “files.txt” > less files.txt View the contents of “files.txt” Use “q” to exit the view. > ls >> files.txt Append the output of the ls command to the file “files.txt” > less files.txt q to quit
- 30. cp: Copy and Paste in one command You must indicate both the from location and the to location > cd > cd workshop > cp files.txt files2.txt Take the file named files.txt and make a copy of it called files2.txt > ls Verify that files2.txt was created. How can I verify that files2.txt is in fact the same as files.txt?
- 31. cp: Copy and Paste in one command You must indicate both the from location and the to location > mkdir file_folder > cp files2.txt file_folder/files3.txt Take files2.txt, make a copy of it named files3.txt and place it in the file_folder directory. > ls > ls file_folder
- 32. mv: Moving files. mv: move a file from one location to the other. Must specify both locations. > cd > cd workshop > cd file_folder > ls > mv files3.txt ../files4.txt > ls > ls .. > cd .. > mv files4.txt file_folder If no new filename is specified when moving to a new directory, then keep the original filename.
- 33. WARNING! cp and mv will write over files that exist of the same name. They behave just like rm. No mercy.
- 34. Self-check Remove the file_folder directory and all its contents Remove .txt files from the workshop directory in one step Move “this” and “that” files to a new directory called “things”
- 36. Fun things to try > whoami > hostname > clear > reboot > sudo reboot