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Copyright (c) 1985 Richard M. Stallman. See end for copying conditions. Portions Copyright (c) 1986 Russell N. Nelson You are looking at the Freemacs tutorial. Freemacs commands generally involve the CONTROL key (sometimes labelled CTRL or CTL) or the META key (sometimes labelled ALT). Rather than write out META or CONTROL each time we want you to prefix a character, we'll use the following abbreviations: C-<chr> means hold the CONTROL key while typing the character <chr> Thus, C-f would be: hold the CONTROL key and type f. M-<chr> means hold the META or ALT key down while typing <chr>. If there is no META or ALT key, type <ESC>, release it, then type the character <chr>. "<ESC>" stands for the key labelled ESC. Important note: if you must exit at some point, type C-X C-C. The characters ">>" at the left margin indicate directions for you to try using a command. For instance: >> Now type C-v (View next screen) to move to the next screen. (go ahead, do it by depressing the control key and v together). From now on, you'll be expected to do this whenever you finish reading the screen. Note that there is an overlap when going from screen to screen; this provides some continuity when moving through the file. The first thing that you need to know is how to move around from place to place in the file. You already know how to move forward a screen, with C-v. To move backwards a screen, type M-v (depress the META key and type v, or type <ESC>v if you don't have a META or ALT key). >> Try typing M-v and then C-v to move back and forth a few times. SUMMARY ------- The following commands are useful for viewing screenfuls: C-v Move forward one screenful M-v Move backward one screenful C-l Clear screen and redisplay everything putting the text near the cursor at the center. (That's control-L, not control-1.) >> Find the cursor and remember what text is near it. Then type a C-l. Find the cursor again and see what text is near it now. BASIC CURSOR CONTROL -------------------- Getting from screenful to screenful is useful, but how do you reposition yourself within a given screen to a specific place? There are several ways you can do this. One way (not the best, but the most basic) is to use the commands previous, backward, forward and next. As you can imagine these commands (which are given to Freemacs as C-p, C-b, C-f, and C-n respectively) move the cursor from where it currently is to a new place in the given direction. Here, in a more graphical form are the commands: Previous line, C-p : : Backward, C-b .... Current cursor position .... Forward, C-f : : Next line, C-n >> Move the cursor to the line in the middle of that diagram and type C-l to see the whole diagram centered in the screen. You'll probably find it easy to think of these by letter. P for previous, N for next, B for backward and F for forward. These are the basic cursor positioning commands and you'll be using them ALL the time so it would be of great benefit if you learn them now. >> Do a few C-n's to bring the cursor down to this line. >> Move into the line with C-f's and then up with C-p's. See what C-p does when the cursor is in the middle of the line. Lines are separated by Newline characters. For most applications there should normally be a Newline character at the end of the text, as well, but it is up to you to make sure of this. A file can validly exist without a Newline at the end. >> Try to C-b at the beginning of a line. Do a few more C-b's. Then do C-f's back to the end of the line and beyond. When you go off the top or bottom of the screen, the text beyond the edge is shifted onto the screen so that your instructions can be carried out while keeping the cursor on the screen. >> Try to move the cursor off the bottom of the screen with C-n and see what happens. If moving by characters is too slow, you can move by words. M-f (Meta-f) moves forward a word and M-b moves back a word. >> Type a few M-f's and M-b's. Intersperse them with C-f's and C-b's. Notice the parallel between C-f and C-b on the one hand, and M-f and M-b on the other hand. Very often Meta characters are used for operations related to English text whereas Control characters operate on the basic textual units that are independent of what you are editing (characters, lines, etc). There is a similar parallel between lines and sentences: C-a and C-e move to the beginning or end of a line, and M-a and M-e move to the beginning or end of a sentence. >> Try a couple of C-a's, and then a couple of C-e's. Try a couple of M-a's, and then a couple of M-e's. See how repeated C-a's do nothing, but repeated M-a's keep moving farther. Do you think that this is right? Two other simple cursor motion commands are M-< (Meta Less-than), which moves to the beginning of the file, and M-> (Meta Greater-than), which moves to the end of the file. You probably don't need to try them, since finding this spot again will be boring. On most terminals the "<" is above the comma and you must use the shift key to type it. On these terminals you must use the shift key to type M-< also; without the shift key, you would be typing M-comma. The location of the cursor in the text is also called "point". To paraphrase, the cursor shows on the screen where point is located in the text. Here is a summary of simple moving operations including the word and sentence moving commands: C-f Move forward a character C-b Move backward a character M-f Move forward a word M-b Move backward a word c-n Move to next line C-p Move to previous line C-a Move to beginning of line C-e Move to end of line M-a Move back to beginning of sentence M-e Move forward to end of sentence M-< Go to beginning of file M-> Go to end of file >> Try all of these commands now a few times for practice. Since the last two will take you away from this screen, you can come back here with M-v's and C-v's. These are the most often used commands. Like all other commands in Freemacs, these commands can be given arguments which cause them to be executed repeatedly. The way you give a command a repeat count is by typing C-u and then the digits before you type the command. If you have a META or ALT key, you can omit the C-u if you hold down the META or ALT key while you type the digits. This is easier, but we recommend the C-u method because it works on any terminal. For instance, C-u 8 C-f moves forward eight characters. >> Try giving a suitable argument to C-n or C-p to come as close as you can to this line in one jump. The only apparent exception to this is the screen moving commands, C-v and M-v. When given an argument, they scroll the screen up or down by that many lines, rather than screenfuls. This proves to be much more useful. >> Try typing C-u 8 C-v now. Did it scroll the screen up by 8 lines? If you would like to scroll it down you can give an argument to M-v. WHEN EMACS IS HUNG ----------------- If Freemacs gets into an infinite (or simply very long) computation which you don't want to finish, you can stop it safely by typing C-g. You can also use C-g to discard a numeric argument or the beginning of a command that you don't want to finish. >> Type C-u 100 to make a numeric arg of 100, then type C-g. Now type C-f. How many characters does it move? If you have typed an <ESC> by mistake, you can get rid of it with a C-g. WINDOWS ------- Freemacs can have two windows, each displaying its own text. At this stage it is better not to go into the techniques of using multiple windows. But you do need to know how to get rid of extra windows that may appear to display help or output from certain commands. It is simple: C-x 1 One window (i.e., kill the other window). That is Control-x followed by the digit 1. C-x 1 makes the window which the cursor is in become the full screen, by getting rid of the other window, if any. >> Type C-x 2 and see this buffer displayed in two windows. >> Type C-x 1 and see the lower window disappear. INSERTING AND DELETING ---------------------- If you want to insert text, just type it. Characters which you can see, such as A, 7, *, etc. are taken by Freemacs as text and inserted immediately. Type <Return> (the carriage-return key) to insert a Newline character. You can delete the last character you typed by typing <Backspace>. More generally, <Backspace> deletes the character immediately before the current cursor position. >> Do this now, type a few characters and then delete them by typing <Backspace> a few times. Don't worry about this file being changed; you can abandon the changes later. >> Now start typing text until you reach the right margin, and keep typing. When a line of text gets too big for one line on the screen, the screen scrolls left so that the cursor remains on the screen. >> Use <Backspace>s to delete the text until the line fits on one screen again. >> Move the cursor to the beginning of a line and type <Backspace>. This deletes the newline before the line and merges the line onto the previous line. The resulting line may be too long to fit, in which case you will see a small arrow pointing right, off the screen. >> Type <Return> to reinsert the Newline you deleted. Remember that most Freemacs commands can be given a repeat count; this includes characters which insert themselves. >> Try that now -- type C-u 8 * and see what happens. You've now learned the most basic way of typing something in Freemacs and correcting errors. You can delete by words or lines as well. Here is a summary of the delete operations: <Backspace> delete the character just before the cursor C-d delete the next character after the cursor M-<Backspace> kill the word immediately before the cursor M-d kill the next word after the cursor C-k kill from the cursor position to end of line M-k kill to the end of the current sentence Notice that <Backspace> and C-d vs M-<Backspace> and M-d extend the parallel started by C-f and M-f (well, <Backspace> isn't really a control character, but let's not worry about that). C-k and M-k are like C-e and M-e, sort of, in that lines are opposite sentences. Now suppose you kill something, and then you decide that you want to get it back? Well, whenever you kill something bigger than a character, Freemacs saves it for you. To yank it back, use C-y. You can kill text in one place, move elsewhere, and then do C-y; this is a good way to move text around. Note that the difference between "Killing" and "Deleting" something is that "Killed" things can be yanked back, and "Deleted" things cannot. Generally, the commands that can destroy a lot of text save it, while the ones that attack only one character, or nothing but blank lines and spaces, do not save. For instance, type C-n a couple times to postion the cursor at some line on this screen. >> Do this now, move the cursor and kill that line with C-k. Note that a single C-k kills the contents of the line, and a second C-k kills the line itself, and make all the other lines move up. If you give C-k a repeat count, it kills that many lines AND their contents. The text that has just disappeared is saved so that you can retrieve it. To retrieve the last killed text and put it where the cursor currently is, type C-y. >> Try it; type C-y to yank the text back. Think of C-y as if you were yanking something back that someone took away from you. Notice that if you do several C-k's in a row the text that is killed is all saved together so that one C-y will yank all of the lines. >> Do this now, type C-k several times. Now to retrieve that killed text: >> Type C-y. Then move the cursor down a few lines and type C-y again. You now see how to copy some text. What do you do if you have some text you want to yank back, and then you kill something else? C-y would yank the more recent kill. But the previous text is not lost. You can get back to it using the M-y command. After you have done C-y to get the most recent kill, typing M-Y replaces that yanked text with the previous kill. Typing M-y again and again brings in earlier and earlier kills. When you have reached the text you are looking for, you can just go away and leave it there. If you M-y enough times, you come back to the starting point (the most recent kill). >> Kill a line, move around, kill another line. Then do C-y to get back the second killed line. Then do M-y and it will be replaced by the first killed line. Do more M-y's and see what you get. Keep doing them until the second kill line comes back, and then a few more. FILES ----- In order to make the text you edit permanent, you must put it in a file. Otherwise, it will go away when your invocation of Freemacs goes away. You put your editing in a file by "finding" the file. What finding means is that you see the contents of the file in your Freemacs; and, loosely speaking, what you are editing is the file itself. However, the changes still don't become permanent until you "save" the file. This is so you can have control to avoid leaving a half-changed file around when you don't want to. Even then, Freemacs can leave the original file under a changed name in case your changes turn out to be a mistake. If you look near the bottom of the screen you will see a line that begins with the string "EMACS (Fundamental) 3: teach.doc". Your copy of the Freemacs tutorial is called "teach.doc". Whatever file you find, that file's name will appear in that precise spot. The commands for finding and saving files are unlike the other commands you have learned in that they consist of two characters. They both start with the character Control-x. There is a whole series of commands that start with Control-x; many of them have to do with files, buffers, and related things, and all of them consist of Control-x followed by some other character. Another thing about the command for finding a file is that you have to say what file name you want. We say the command "reads an argument from the terminal" (in this case, the argument is the name of the file). After you type the command C-x C-f Find a file Freemacs asks you to type the file name. It echoes on the bottom line of the screen. You are using the minibuffer now! this is what the minibuffer is for. When you type <Return> to end the file name, the minibuffer is no longer needed, so it disappears. >> Type C-x C-f, then type C-g and C-g. This cancels the minibuffer, and also cancels the C-x C-f command that was using the minibuffer. So you do not find any file. In a little while the file contents appear on the screen. You can edit the contents. When you wish to make the changes permanent, issue the command C-x C-s Save the file The contents of Freemacs are written into the file. You should save fairly often, so that you will not lose very much work if the system should crash. >> Type C-x C-s, saving your copy of the tutorial. To make a new file, just find it "as if" it already existed. Then start typing in the text. When you ask to "save" the file, Freemacs will really create the file with the text that you have inserted. >From then on, you can consider yourself to be editing an already existing file. BUFFERS ------- If you find a second file with C-x C-f, the first file remains inside Freemacs. You can switch back to it by finding it again with C-x C-f. This way you can get quite a number of files inside Freemacs. The object inside Freemacs which holds the text read from one file is called a "buffer." Finding a file makes a new buffer inside Freemacs. To see a list of the buffers that exist in Freemacs, type C-x C-b List buffers >> Try C-x C-b now. See how each buffer has a name, and it may also have a file name for the file whose contents it holds. Only those buffers that say FILE were loaded by yourself. Any other buffers were created by Freemacs, with the exception of Main. >> Type Space to get rid of the buffer list. If you make changes to the text of one file, then find another file, this does not save the first file. Its changes remain inside Freemacs, in that file's buffer. The creation or editing of the second file's buffer has no effect on the first file's buffer. This is very useful, but it also means that you need a convenient way to save the first file's buffer. It would be a nuisance to have to switch back to it with C-x C-f in order to save it with C-x C-s. So we have C-x C-m Write modified files C-x C-m goes through the list of all the buffers you have and finds the ones that contain files you have changed, and saves them. EXTENDING THE COMMAND SET ------------------------- There are many, many more Freemacs commands than could possibly be put on all the control and meta characters. Freemacs gets around this with the X (eXtend) command. This comes in two flavors: C-x Character eXtend. Followed by one character. M-x Named command eXtend. Followed by a long name. These are commands that are generally useful but used less than the commands you have already learned about. You have already seen two of them: the file commands C-x C-f to Find and C-x C-s to Save. Another example is the command to tell Freemacs that you'd like to stop editing and get rid of Freemacs. The command to do this is C-x C-c. (Don't worry; it offers to save each changed file before it kills Freemacs.) C-x C-z is the usual way to exit Freemacs, because it is always better not to kill the Freemacs if you are going to do any more editing. C-x C-z creates a subshell running under Freemacs to give you the chance to run other programs and return to Freemacs afterward, but it does not truly "exit" from Freemacs. To return to Freemacs, use "exit". There are many C-x commands. The ones you know are: C-x C-f Find file. C-x C-s Save file. C-x C-b List buffers. C-x C-c Quit Freemacs. Named eXtended commands are commands which are used even less frequently, or commands which are used only in certain modes. These commands are usually called "functions". An example is the function query-replace, which globally replaces one string with another. When you type M-x, Freemacs prompts you at the bottom of the screen with M-x and you should type the name of the function you wish to call; in this case, "query-replace". Just type "que " and Freemacs will complete the name. Then type the two "arguments"--the string to be replaced, and the string to replace it with--each one ended with a Return. >> Move the cursor to the blank line two lines below this one. Then type M-x que<Return>changed<Return>altered<Return>!. Notice how this line has changed: you've replaced the word c-h-a-n-g-e-d with "altered" wherever it occured after the cursor. MODE LINE --------- Freemacs shows the commands that you are typing at the bottom of the screen in an area called the "echo area." The echo area contains the bottom line of the screen. The line immediately above it is called the MODE LINE. The mode line says something like -----Emacs:2: c:\emacs\tutorial.doc [FILE] (Text) C44 L481/736 --67-- This is a very useful "information" line. You already know what the filename means--it is the file you have found. [FILE] means that this is a file that you have found, as opposed to one created by Freemacs. What the C44 L481/736 means is that you are at column 44 and line 481 of a file that is 736 lines long. The dashes at the left will contain stars if you have made changes to the text. Right after you visit or save a file, there are no stars. The part of the mode line inside the parentheses is to tell you what modes you are in. The default mode is Fundamental. Since this is a text file, the mode is "Text". It is an example of a "major mode". There are several major modes in Freemacs for editing different languages and text, such as Mint mode, C mode, etc. At any time one and only one major mode is active, and its name can always be found in the mode line just where "Text" is now. Each major mode makes a few commands behave differently. For example, there are commands for creating comments in a program, and since each programming language has a different idea of what a comment should look like, each major mode has to insert comments differently. Each major mode is the name of an extended command, which is how you get into the mode. For example, M-X Fun-mode is how to get into Fundamental mode. Other modes have the word mode in their names. If you are going to be editing English text, such as this file, you should probably use Text Mode. >> Type M-x Text-mode<Return>. Don't worry, none of the commands you have learned changes Freemacs in any great way. Major modes are usually like that: commands don't change into completely unrelated things, but they work a little bit differently. Major modes are called major because there are also minor modes. They are called minor because they aren't alternatives to the major modes, just minor modifications of them. Each minor mode can be turned on or off by itself, regardless of what major mode you are in, and regardless of the other minor modes. So you can use no minor modes, or one minor mode, or any combination of several minor modes. One minor mode which is very useful, especially for editing English text, is Auto Fill mode. When this mode is on, Freemacs breaks the line in between words automatically whenever the line gets too long. You can turn this mode on by doing M-x auto-fill-mode<Return>. When the mode is on, you can turn it off by doing M-x auto-fill-mode<Return>. If the mode is off, this function turns it on, and if the mode is on, this function turns it off. This is called "toggling". >> Type M-x auto-fill-mode<Return> now. Then insert a line of "asdf " over again until you see it divide into two lines. You must put in spaces between them because Auto Fill breaks lines only at spaces. The margin is usually set at 70 characters, but you can change it with the C-x f command. You should give the margin setting you want as a numeric argument. >> Type C-x f with an argument of 20. (C-u 2 0 C-x f). Then type in some text and see Freemacs fill lines of 20 characters with it. Then set the margin back to 70 using C-x f again. If you makes changes in the middle of a paragraph, Auto Fill mode does not re-fill it for you. To re-fill the paragraph, type M-q (Meta-q) with the cursor inside that paragraph. >> Move the cursor into the previous paragraph and type M-q. SEARCHING --------- Freemacs can do searches for strings (these are groups of contiguous characters or words) either forward through the file or backward through it. To search for the string means that you are trying to locate it somewhere in the file and have Freemacs show you where the occurrences of the string exist. This type of search is somewhat different from what you may be familiar with. It is a search that is performed as you type in the thing to search for. The command to initiate a search is C-s for forward search, and C-r for reverse search. BUT WAIT! Don't do them now. When you type C-s you'll notice that the string "I-search" appears as a prompt in the echo area. This tells you that Freemacs is in what is called an incremental search waiting for you to type the thing that you want to search for. <Return> terminates a search. >> Now type C-s to start a search. SLOWLY, one letter at a time, type the word 'cursor', pausing after you type each character to notice what happens to the cursor. >> Type C-s to find the next occurrence of "cursor". >> Now type <Backspace> four times and see how the cursor moves. >> Type <Return> to terminate the search. Did you see what happened? Freemacs, in an incremental search, tries to go to the occurrence of the string that you've typed out so far. To go to the next occurrence of 'cursor' just type C-s again. If no such occurrence exists Freemacs beeps and tells you that it is a failing search. C-g would also terminate the search. If you are in the middle of an incremental search and type <Backspace>, you'll notice that the last character in the search string is erased and the search backs up to the last place of the search. For instance, suppose you currently have typed 'cu' and you see that your cursor is at the first occurrence of 'cu'. If you now type <Backspace>, the 'u' on the search line is erased and you'll be repositioned in the text to the occurrence of 'c' where the search took you before you typed the 'u'. This provides a useful means for backing up while you are searching. If you are in the middle of a search and happen to type a control character (other than a C-s or C-r, which tell Freemacs to search for the next occurrence of the string), the search is terminated. The C-s starts a search that looks for any occurrence of the search string AFTER the current cursor position. But what if you want to search for something earlier in the text? To do this, type C-r for Reverse search. Everything that applies to C-s applies to C-r except that the direction of the search is reversed. GETTING MORE HELP ----------------- The Help system hasn't been written yet. Any takers? In this tutorial we have tried to supply just enough information to get you started using Freemacs. There is so much available in Freemacs that it would be impossible to explain it all here. However, you may want to learn more about Freemacs since it has numerous desirable features that you don't know about yet. Freemacs has a great deal of internal documentation. All of these commands can be accessed through the key F1, which we call "the Help character" or <HELP> because of the function it serves. To use the HELP features, type the <HELP> character, and then a character saying what kind of help you want. If you are REALLY lost, type <HELP> ? and Freemacs will tell you what kinds of help it can give. If you have typed <HELP> and decide you don't want any help, just type C-G to cancel it. The most basic HELP feature is <HELP> c. Type <HELP>, a c, and a command character or sequence, and Freemacs displays a very brief description of the command. >> Type <HELP> c Control-p. The message should be something like C-p is previous-line This tells you the "name of the function". That is important in writing Lisp code to extend Freemacs; it also is enough to remind you of what the command does if you have seen it before but did not remember. Multi-character commands such as C-x C-s and (if you have no META or ALT key) <ESC>v are also allowed after <HELP> c. To get more information on the command, use <HELP> k instead of <HELP> c. >> Type <HELP> k Control-p. This displays the documentation of the function, as well as its name, at the top of the screen. Press a key to continue, only space will be discarded... Here are some other useful <HELP> options: <HELP> f Describe a function. You type in the name of the function. >> Try typing <HELP> f previous-line<Return>. This prints all the information Freemacs has about the function which implements the C-P command. <HELP> a Apropos. Type in a keyword and Freemacs will list all the commands whose names contain that keyword. These commands can all be invoked with Meta-x. For some commands, Apropos will also list a one or two character sequence which has the same effect. >> Type <HELP> a file<Return>. You will see a list of all M-x commands with "file" in their names. You will also see commands like C-x C-f and C-x C-w, listed beside the command names find-file and write_file. CONCLUSION ---------- Remember, to exit Freemacs permanently use C-x C-c. To exit to a shell temporarily, so that you can come back in, use C-x C-z. This tutorial is meant to be understandable to all new users, so if you found something unclear, don't sit and blame yourself - complain! COPYING ------- This tutorial, like all of Freemacs, is copyrighted, and comes with permission to distribute copies on certain conditions: Copyright (c) 1985 Richard M. Stallman Permission is granted to anyone to make or distribute verbatim copies of this document as received, in any medium, provided that the copyright notice and permission notice are preserved, and that the distributor grants the recipient permission for further redistribution as permitted by this notice. Permission is granted to distribute modified versions of this document, or of portions of it, under the above conditions, provided also that they carry prominent notices stating who last altered them. The conditions for copying Freemacs itself are slightly different but in the same spirit. Please read the file LICENSE and then do give copies of Freemacs to your friends. Help stamp out ownership of software by using, writing, and sharing free software!