290: Stat Introduction to Unix and Emacs
Objectives
1. To introduce basic emacs commands 2. To introduce some basic unix commands
Notation
The notation C-g means to hold down the Control key and hit the g key, while M-a means to invoke the Meta key (either hold down the Alt key, or press and release the Esc key, depending on your keyboard - I use the latter) and hit the a key.
Reminders
If something starts to go horribly wrong, use C-g to cancel the current command (infrequently, you may need to use it several times). You can also undo commands successively with either C-x u or C- (thats Control-underscore). Recall that C-x C-c will quit emacs, and C-z will suspend it, shrinking the window into an icon. The help menus in emacs are triggered with C-h and are quite extensive.
Introduction to Emacs
Start up Emacs by typing at the unix command prompt: emacs & Note that the ampersand runs the process in the background, so that you can continue to use the unix shell window while emacs is running. If you forgot the ampersand, at the unix prompt type C-z, then enter bg to put emacs in the background. Now type the following into your emacs window: Your name (on the rst line), your department on the second line, followed by a blank line, for example: Merlise Clyde Institute of Statistics and Decision Sciences
Cursor Movement
Now well walk through a variety of cursor movement commands. Try the following to get accustomed to moving the cursor without using the arrows or the mouse. Hit M-< to move to the beginning of the buer. C-f moves you forward one character, C-b moves you back. M-f moves you forward one word, M-b moves you back one word. C-n moves you down to the next line, C-p moves you up to the previous line. C-e moves you to the end of the line, C-a moves you to the beginning of the line. If your document scrolled over more than one screen, you can use C-v to scroll down and M-v to scroll up. 1
Files and Buers
Suppose you now want to save this unnamed le (or if it already had a name, supposed you wanted to rename it). To write a le to disk, use C-x C-w and then type in the name of the le, myname.txt and hit enter, as in: C-x C-w merlise.txt Now well update the le. Move to the last line of the le, and add the following information to your le: previous applied and theoretical statistics courses that you have taken at Duke and/or other institutions (please name), experience with S-Plus or R, experience with LaTeX, familiarity with Unix. (Depending on how your defaults are set up, emacs may or may not automatically insert line breaks when you type too close to the right hand margin. If it does not, you can get it to x your paragraph By typing M-q. The technical term for this is auto-ll.) Now save your updated le by typing C-x C-s. This is the standard way of saving your le. Emacs does have an auto-save feature, but you should get into the habit of saving your work very frequently as you work, just in case something bad should happen. Without closing emacs, open a new le (the previous le, myname.txt, will still be open, but in a dierent buer) by typing C-x C-f lab1hw.txt Tell me a little bit about what type of applications interest you or topics that you would like to learn about in this course. Save this le with C-x C-s. Since myname.txt is still in another buer, we can still access it. To switch to another buer, type in C-x b and it will ask you which buer you wish to switch to. The default will be myname.txt, so you can just hit enter (otherwise you can type in the name of the buer you want). In this way, you can have many les open in the same emacs process, and just switch between them as need be. You can also have more than one displayed at the same time. Split the screen by typing C-x 2 You will now have two buers, each half the size of the emacs window, each containing the same le. Switch one of them to lab1hw.txt using C-x b. Now you have easy access to both les. To move the cursor between the buers, use C-x o. To go back to a single window (just the window containing the use cursor) C-x 1. You can close a le with C-x k (this kills the buer), but leave the two les open, as well continue to use them in the next section.
Cut, Copy, and Paste
Bring myname.txt to the front of your emacs window (if it isnt already, use C-x b to switch buers, or C-x C-f to open it from the disk if youve closed it). Suppose we want to move the two sentences name and department to the le lab1hw.txt. Move your cursor to the rst letter of the rst sentence and then type Control-space. This sets the mark at that character. Now move past the end of the second sentence and type C-w. This cuts the marked section. (If you miss, you 2
can use C- to undo.) If we just wanted to delete this part, we have done so and can just move on, but we want to move it, so we need to paste it back in. Switch to the lab1hw.txt buer, move to the beginning of the document (M-< is the shortcut) and type in C-y (yank is the mnemonic) to paste in the text. Move to the end of the le (M->) and paste another copy with C-y. This is just to practice a dierent deletion technique. Move your cursor back to the beginning of the section that was just pasted in and use C-k to kill all the text on the same line to the right of the cursor. Use C-k repeatedly until all the freshly pasted text has been removed. Finally, you should know that M-w will copy text to the kill buer (like C-w) but without deleting it, so that you can paste it elsewhere without removing the original. You can either save your work with C-x C-s, or kill all the recent changes by killing the buer C-x k and entering yes when it asks for conrmation of closing without saving. Were done with emacs for now, so you can close it with C-x C-c.
Basic Unix Commands
Back in your unix shell window, type ls After hitting enter, you will get a list of all the les in the current directory. You may have started in your root directory (), which probably isnt where you want these les. Make a new directory for this class by typing mkdir sta290 Now move the new le into this directory, rst use mv myname.txt sta290/. Note that the period at the end says to keep the name of the le the same. For the second le, use tab-completion so that you dont have to type in the whole le name, i.e., instead of typing in mv lab1hw.txt sta290/., type in (without hitting enter) mv la and hit the tab key so that unix will ll in the rest of the name (or as much as it can if there are m...