Before going to Lab 02, you should have completed and understood both Lab 1 and Homework 0. You should have already created directories for your 201 files, including the main 201 folder, directories called Labs and Homeworks, and directories inside those with appropriate names (e.g., hw0, lab1, etc.).
You should already know a number of commands that you can use in GL's command line (the "terminal") from the previous assignments. We will briefly cover those, and will introduce a few other useful commands as well. You are not expected to master all of these, or to do so immediately — we are simply reminding you that these tools exist.
| Command | Purpose and Example Usage |
|---|---|
| cd | Change your current directory Usage: cd lab2 to move to the lab2 directory (Use cd .. to move up one directory; use cd alone to go back to your home directory) |
| ls | List the contents of the current directory |
| mkdir | Create a new directory Usage: mkdir lab2 to make a new lab2 directory if it doesn't already exist |
| mv | Rename a file (i.e., "move" the file to a new name) Usage: mv oldName.py newName.py will rename the file from oldName.py to newName.py |
| pwd | Print the full path of the "working" (current) directory |
| submit | Allows you to submit assignments over GL Usage: submit cs201 HW1 hw1.txt submits the file hw1.txt to the HW1 assignment for the cs201 class |
All of the commands above you've seen before. Here are some new commands that you might not have used yet, but that can be very helpful.
| Command | Purpose and Example Usage |
|---|---|
| cp | Create a copy of an existing file Usage: cp existingFile.txt newFileName.txt will create a copy of the existing file, and name the copy "newFileName.txt" |
| clear | "Clears" your screen by shifting your previous commands and output upward; you can still scroll up using the mouse or scrollbar |
| "TAB" | Hitting the tab key will autocomplete based on the available file or directory names. For example, typing "emacs la" and hitting tab will autocomplete "la" to "lab2.py" if the file exists |
| "up arrow" | Hitting the up arrow will recall your previous command to the terminal. Hitting it again will pull up the command before that one; repeat as necessary. |
There are many more useful commands that you can use in GL, and we'll mention them as they come up during the semester. If you see your TA or instructor using a command or shortcut that you don't know and would like to be able to use, ask them to explain it to you!
Finally, let's cover some basic emacs shortcuts. Again, you will already know some of these from doing previous assignments, but some of them will also be new to you. You do not "need" to know any of them beyond the first two (how to save your file and how to exit emacs), but mastering a few more will make your programming experience more enjoyable.
| Command | Purpose and Example Usage |
|---|---|
| CTRL+X, CTRL+S | Save the file and stay in emacs |
| CTRL+X, CTRL+C | Save the file and close emacs |
| CTRL+_ | Undo your last edit; use it again to undo the previous one as well (Control+Shift+"-" to create an underscore) |
| CTRL+K | Remove everything on the line after the cursor ("kill") |
| CTRL+Y | Paste the line cut by the CTRL+K command ("yank") |
| CTRL+A | Move the cursor to the beginning of the current line |
| CTRL+E | Move the cursor to the end of the current line |