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J O V E T U T O R I A L Welcome to JOVE - an advanced, easy-to-use, user-friendly environment for editing text, programs or anything else you may like to type. JOVE commands generally involve the CONTROL key (sometimes labelled CTRL or CTL) or the META key (generally labelled ESCAPE). 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 type the META (ESCAPE) key and release it, then type the character <chr>. The <chr> can be upper or lower case and it will have the same meaning. 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 EDIT 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 Center the current line--clear screen and redisplay everything if current line is already at center. >> 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 JOVE 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 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 several C-P's. See what C-P does when the cursor is in the middle of the line. Lines are separated by a single Linefeed character, which is what Unix calls a Newline. >> 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. If you need the shift key to type a "<", then you must also use the shift key to type M-<. Otherwise, you would be typing M-, . 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 the command C-X C-X (which will be explained later). These are the most often used commands. Like all other commands in JOVE, 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 META and then the digits before you type the command. (Remember META is ususally called ESCAPE) For instance, META 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 M-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. THE UNIVERSAL ARGUMENT ---------------------- Almost every command in JOVE takes a so-called Universal Argument. This argument, although it is interpreted differently in some cases, usually means REPEAT. The way you give a command a universal argument is by typing ESC and then the number. For example, ESC 10 C-F would move you forward ten 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. Then try giving the same command, except make the number negative. Another count-giving command is C-U. This command, when you first type it, gives you an argument of 4 (four). If you type C-U C-U, you will get an argument of 16. Each time C-U is typed, the argument is multiplied by four. One important exception to this is with the screen moving commands. In this case, the number refers to the number of LINES to scroll, not the number of screens. As a special case, C-U C-V or C-U M-V will scroll exactly one half screenful. >>> Try typing ESC 8 C-V now. THE GOTO COMMAND ---------------- Now that we've learned about the universal argument, we can introduce another cursor positioning command, the command to move to a specific line. This command is given by giving a line number via ESC, and then typing M-G. >>> Try using the M-< and M-> commands to move to the beginning and the end of the file. Then come back here using the M-G command (this is line 164, so you'd type ESC 164 M-G.) QUITTING FROM COMMANDS ---------------------- The character in JOVE used to quit out of all commands which request input is C-G. For example, you can use C-G to discard a numeric argument or the beginning of a command that you don't want to finish. >> Type M-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. ERRORS ------ Sometimes you may do something which JOVE doesn't allow. If it is something simple, such as typing a control key sequence which is not associated with any command, JOVE will just beep at you. Otherwise, JOVE will also display an informative error message at the bottom of the screen. Some versions of JOVE do not have all the features described in this tutorial implemented yet. If you come across such an unimplemented feature, you may get an error message when you try to use it. Just proceed on to the next section of the tutorial. INSERTING AND DELETING ---------------------- If you want to type text, just do it. Characters which you can see, such as A, 7, *, etc. are taken by JOVE as text and inserted immediately. Type <Return> (the carriage-return key) to insert a line separator. You can delete the last character you typed by typing <Delete>. <Delete> is a key on the keyboard, which may be labeled "Rubout" instead of "Delete" on some terminals. More generally, <Delete> deletes the character immediately before the current cursor position. >> Do this now, type a few characters and then delete them by typing <Delete> a few times. Don't worry about this file being changed; you won't affect the master tutorial. This is just a copy of it. >> 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 line of text is "continued" off the edge of the screen The exclamation mark at the right margin indicates a line which has been continued. The line will slide over if you move off the edge on either side. >> The following line actually goes off the edge. Trying typing enough C-F's that you move off the right hand end of this line.... This is a long line of text that the JOVE editor extends to the right. >> Use <Delete>s to delete the text until the line fits on one screen line again. The continuation "!" will go away. >> Move the cursor to the beginning of a line and type <Delete>. This deletes the line separator before the line and merges the line onto the previous line. The resulting line may be too long to fit, in which case it has a continuation indication. >> Type <Return> to insert the separator again. Remember that most JOVE commands can be given a repeat count; Note that this includes characters which insert themselves. >> Try that now -- type META 8 * and see what happens. If you want to create a blank line in between two lines, move to the second of the two lines and type C-O. >> Try moving to a line and typing C-O now. You've now learned the most basic way of typing something in JOVE and correcting errors. You can delete by words or lines as well. Here is a summary of the delete operations: <Delete> delete the character just before the cursor C-D delete the next character after the cursor M-<Delete> 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 <Delete> and C-D vs M-<Delete> and M-D extend the parallel started by C-F and M-F (well, <Delete> 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, JOVE saves it for you. To yank it back, use C-Y. Note that you don't have to be in the same place to do C-Y; This is a good way to move text around. Also 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. If you like, you can try giving M-Y positive and negative arguments. 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 JOVE goes away. While you are editing a file in JOVE, your changes are actually being made to a private "scratch" copy of the file. 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. If you look near the botton of the screen you will see a line that looks like this: JOVE (Text) Buffer: teach-jove "teach-jove" * "teach-jove" is the name of the file you are editing. This is the name of your own temporary copy of the text of the JOVE tutorial; the file you are now editing. Whatever file you edit, 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. As with M- the character interpreted the same regardless of case. 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 JOVE will ask you for the file name. You should end the name with the Return key. After this command, you will see the contents of the file in your JOVE. You can edit the contents. When you wish to make the changes permanent, issue the command C-X C-S Save the file Warning: on many systems JOVE will not be able to process the key C-S. In place of C-S, you should type C-\. It is possible to make C-S work but C-\ is guaranteed always to work in place of C-S. The old version of the file will be replaced. When the operation is finished, JOVE prints the name and number of lines and characters saved. If you forget to save and then edit a different file, JOVE will remind you that you made changes that have not been saved and then ask you whether you really want to quit. (If you don't save them, they will be thrown away. That might be what you want!) You should answer with a "Y" to throw the changes away or "N" to abort quitting so you can then save the changes. To make a new file, just edit it "as if" it already existed. Then start typing in the text. When you ask to "save" the file, JOVE 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. It is not easy for you to try out editing a file and continue with the tutorial. But you can always come back into the tutorial by starting it over and skipping forward. So, when you feel ready, you should try editing a file named "FOO", putting some text in it, and saving it; then exit from JOVE and look at the file to be sure that it worked. CONCLUSION OF PART ONE ---------------------- This is the end of the first part of this tutorial. You now know enough to edit a file with JOVE, and save your work. The second part of this tutorial, which starts with the next section, discusses searching, replacing, word processing, and other modes of JOVE. You may wish to stop here and practice for awhile before you continue. EXTENDING THE COMMAND SET ------------------------- There are many, many more JOVE commands than could possibly be put on all the control and meta characters. JOVE 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 JOVE that you'd like to stop editing. The command to do this is C-X C-C. There are many C-X commands. The ones you need immediately are: C-X C-V Visit file. C-X C-S Save file. C-X C-C Quit JOVE. This does not save your files auto- matically, though if your files have been modi- fied, JOVE asks if you really want to quit. The standard way to save and exit is C-X C-S C-X C-C. 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 "commands". An example is the command "apropos", which prompts for a keyword and then gives the names of all the commands that apropos for that keyword. When you type M-X, JOVE prompts you at the bottom of the screen with ":" and you should type the name of the command you wish to call; in this case, "apropos". Just type "apr<Space>" and JOVE will complete the name. JOVE will ask you for a keyword or phrase and you type the string that you want ask about. >> Try typing M-X, followed by "apropos" or "apr" and then Return. Then try typing "file" followed by a Return. MODE LINE --------- If JOVE sees that you are typing commands slowly it shows them to you 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 them is called the MODE LINE. The mode line says something like JOVE (Text) Buffer: [buffername] "filename" * This is a very useful "information" line. The buffername is the name JOVE gave to the buffer, and it is usually related to the filename. You already know what the filename means -- it is the file you have edited. The star means that you have made changes to the text. Right after you visit or save a file, there is no star. The part of the mode line inside the parentheses is to tell you what modes you are in. The default mode is Text which is what you are in now. It is an example of a "major mode". There are several major modes in JOVE for editing different languages and text, such as C mode, Lisp mode, Text mode, etc. At any time one and only one major mode is active, and its two-letter code can always be found in the mode line just where "Text" is now. Each major mode makes a few commands behave differently. For example, what JOVE considers as part of a valid expression or an identifier differs from one major mode to another, since each programming language has a different idea of what is a legal identifier. 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, JOVE 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>-- it toggles. >> Type "M-X auto-fill-mode<Return>" now. Then insert a line with a bunch of words 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. Notice that "Fill" (the code for Auto Fill) appears in the mode line after "Text" to indicate that you are in Text Fill mode. The margin is usually set at 78 characters, but you can change it with the set command. The margin is kept in a variable just like the mode values. >> Type "M-X set right-margin 20", then type in some text and see JOVE fill lines of 20 characters with it. Then set the margin back to 72 using M-X set again. SEARCHING --------- JOVE 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 find that string somewhere in the file. Remember to use C-\ where it says C-S. >> Now type C-S to start a search. Type the word 'cursor', then Return. >> Type C-S Return to find the next occurrence of "cursor". 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 one should 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. REPLACING TEXT -------------- >> Move the cursor to the blank line two lines below this one. Then type M-r 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 occurs after the cursor. The more customary command for replacing strings is the interactive command query-replace-search, which has several options. In essence, it shows each occurrence of the first string and asks you if you want to replace it or not. You can also choose to edit around the string, or go on and replace all occurrences without asking further. This is invoked with M-Q.. When you start up a Query Replace, it will prompt you with "From" and "To", for what you want to change, and what you want to change it to. JOVE will then move to the first occurence of the "From", and wait for a character. You can type: <SPACE> Do the replacement, and move to next occurrence of the "From" string. <DEL> Skip the current "From" string and move to the next one. RETURN Exit the Query Replace now. r Recursive Edit p Replace all further occurences of the "From" string, without asking. Recursive edit makes it possible to temporarily supend the Q-R-S, let the user go off and do something, and then return to the search after the he is done. The command exit-jove (C-X C-C) returns from the recursive-edit. GETTING MORE HELP ----------------- In this tutorial we have tried to supply just enough information to get you started using JOVE. There is so much available in JOVE that it would be impossible to explain it all here. However, you may want to learn more about JOVE since it has numerous desirable features that you don't know about yet. JOVE has a some internal documentation. The most basic HELP feature is the describe-key command which is available by typing C-X ? and then a command character. JOVE prints one line line on the bottom of the screen tell what command is bound to that key. You can then get further information on that command using... The describe-command command M-? will prompt for the name of a command and print out the section from the manual about that command. When you are finished reading it, type a Space or a C-G (quit) to bring your text back on the screen. >> Type C-X ? Control-P. The message at the bottom of the screen should be something like "C-P is bound to previous-line". Multi-character commands such as C-X C-C and <ESC>V are also allowed after C-X ?. Now lets get more information about the previous-line command. >> Type M-? previous-line. When you are finished reading the output, type a Space. The "name of the command" is important for people who are customizing JOVE. It is what appears in the JOVE CHART as the documentation for the command character. One other form of help is the "apropos" command. We have already tried using this command in an earlier part of this tutorial, but it should be mentioned again here. Apropos prompts for a word or phrase and lists all the commands that contain that string. If you couldn't remember the name of a certain command to read file, you could run the apropos command with the keyword "file" and it would list all the commands that contain "file". To run apropos you would type M-X apr<Space>file<Return> Finally, the full set of JOVE manuals are in five parts, and reside in the directory /usr/src/local/jove/doc under the names jove.1 to jove.5. These are in TROFF form, and the documents in /usr/src/local/jove/doc/docs are in a form readable on the terminal or line-printer. Besides, someone around you must have a printed version which you can borrow! There is also a chart of JOVE commands, sorted by function, which is handy as a quick reference. CONCLUSION OF PART TWO ---------------------- This concludes section two of the JOVE tutorial. The rest of this tutorial describes some of the very advanced features of JOVE, such as editing more than one file at once, writing your own macros, windows, and initialization files. Unless you're already somewhat familiar with JOVE, you should probably wait a little while before starting the third section. MARKS AND REGIONS ----------------- In general, a command which processes an arbitrary part of the buffer must know where to start and where to stop. In JOVE, such commands usually operate on the text between point (where the cursor is now) and "the mark". This range of text is called "the region". To specify a region, you set point to one end of it and mark at the other. It doesn't matter which one is set first chronologically, or which one comes earlier in the text. Here are some commands for setting the mark: C-@ Set the mark where point is. C-<SPACE> The same. C-X C-X Interchange mark and point. The most common way to set the mark is with the C-@ command or the C-<SPACE> command. They set the mark where point is. Then you can move point away, leaving the mark behind. Since terminals have only one cursor, there is no way for JOVE to show you where the mark is located. You have to remember. The usual solution to this problem is to set the mark and then use it soon, before you forget where it is. But you can see where the mark is with the command C-X C-X which puts the mark where point was and point where the mark was. The extent of the region is unchanged, but the cursor and point are now at the previous location of the mark. If you insert or delete before the mark, the mark may drift through the text. If the buffer contains "FOO BAR" and the mark is before the "B", then if you delete the "F" the mark will be before the "A". This is an unfortunate result of the simple way the mark is implemented. It is best not to delete or insert at places above the mark until you are finished using it and don't care where it drifts to. There are many, many commands which use regions (the area between the point and the mark), which we have not mentioned here. They are all similar to such things as "transpose paragraphs", etc., and can be found in the wall chart. BUFFERS ------- When editing a file, JOVE reads the file into a buffer. This is where the modifcations are done, and when you save the file with C-X C-S, the buffer is actually written out to the file. JOVE permits you to have up to 100 buffers, so, in essence, you can edit up to 100 files at the same time. If you want to list the buffers you have, use the C-X C-B command. This will display a list of the buffers, their numbers and names, and whether or not they've been modified. >>> Do this now, type C-X C-B. When you're done looking, type a <SPACE>. You probably noticed you only have one buffer, named "Main". If you were editing more than one file, however, you would have more than one buffer. There are two ways to edit more than one file. The first is to call JOVE with more than one file on the command line. For example, the command jove a b c would create three buffers (named Main, b, and c), each one containing one file. The other way is to use the C-X C-F command (called Find File). This command prompts you for a filename, and then reads that file into a new buffer, and puts you into the new buffer. To change buffers, use the C-X B command. JOVE will prompt you for a buffer name, and print a name in parentheses. If you just hit a carriage return without typing a buffer name, you will go to the buffer named in parentheses. Another way to change buffers is to give C-X B an argument with C-U. This goes to the buffer NUMBER, rather than using the buffer name. >>> Get a piece of paper, and write down the following commands. Then run them, to get a feel for playing with buffers. BE SURE TO WRITE THEM DOWN! We don't want to get you lost! C-X C-B <SPACE> C-X C-F (type "/etc/motd" to the prompt) C-X C-B <SPACE> C-X B <RETURN> Well, wasn't that fun? Now you know how to get another file into another buffer, and then "bounce" back and forth. A nice feature about editing more than one file is that you can transfer text from one file to the other. Just kill it in one file, change buffers, and then put it back with C-Y. WINDOWS ------- What you see on your screen is a "window" into the buffer you are editing. JOVE allows you to have more than one window on your screen, and you can therefore look into two, or more buffers at once. You can also look at different parts of the same file. The command C-X 2 splits your screen into two windows, both looking into the same buffer. The command C-X 4 f will display a specified file in the other window, C-X 4 b will display a specified buffer in the other window, C-X n moves to the next window on the screen, while C-X p moves to the previous window. >>> Try the command C-X 2, which splits the screen into two windows, and displays the same buffer in both. You'll notice that you are in the new window. Try some commmands in this window, like C-V, or M-V, to move around in the file. Observe that the other window doesn't change its position realtime to the buffer. This gives you a way of looking at two parts of the same file. >>> Now try to type some text, or change something. You will see the changes affecting the text in the other window as well. That is because both windows are displaying the same buffer, and therefor the same text. Changes in the contents of the buffer have to affect both windows. >>> Let's now try to edit another file in this window. Give the command C-X C-F and type the name of file as "/etc/motd". You now have two files on your screen at the same time. >>> Type the command M- C-V (Meta followed by C-V) and watch the other window page downward. This is very convenient when doing a variety of tasks, like correcting errors in a file - edit the file, with the list of errors in the other window! >>> Finally, let's get back to the main window (with this document) by typing C-X p (or C-X n, since there are only two windows). Expand this window to fill the entire screen by typing C-X 1. Enjoyable, wasn't it! There are other commands for shrinking and growing windows, but one of the most useful when editing text like this is the command which invokes JOVE's interactive spelling checker. It's called spell-buffer. It runs the UNIX spell(1) command on the buffer, and puts the errors in another buffer in another window, and allows you to edit the list to remove the words you know are not errors. Then, type C-X C-C, which usually gets you out of JOVE but in this case only gets you out of the spell-edit mode. You can now go through the remaining spelling errors word-by-word, and you can correct them. The commands for this are C-X C-N (for next error) and C-X C-P (for previous error.) >>> Try the spell-buffer command now, by going M-X spel <space> and watch. Delete a few errors, then type C-X C-C, and do a few C-X C-N's to find some errors in this document. We've left a few ! (deliberately, of course!!!) MACROS ------ A "keyboard macro" is a command defined by the user to abbreviate a sequence of other commands. If you discover that you are about to type C-N C-D forty times, you can define a keyboard macro to do C-N C-D and call it with a repeat count of forty. The commands which deal with keyboard macros are: C-X ( Start defining a keyboard macro. C-X ) End the definition of a keyboard macro. C-X E Execute the most recent keyboard macro. You define a keyboard macro while executing the commands which are the definition. Put differently, as you are defining a keyboard macro, the definition is being executed for the first time. This way, you can see what the effects of your commands are, so that you don't have to figure them out in your head. When you are finished, the keyboard macro is defined and also has been, in effect, executed once. You can then do the whole thing over again by invoking the macro. To start defining a keyboard macro, type the C-X ( command. From then on, your commands continue to be executed, but also become part of the definition of the macro. "Def" appears in the mode line to remind you of what is going on. When you are finished, the C-X ) command terminates the definition (without becoming part of it!). The macro thus defined can be invoked again with the C-X E command which may be given a repeat count as a numeric argument to execute the macro many times. C-X ) can also be given a repeat count as an argument, in which case it repeats the macro that many times right after defining it, but defining the macro counts as the first repetition (since it is executed as you define it). So, giving C-X ) an argument of 2 executes the macro immediately one additional time. An argument of zero to C-X E or C-X ) means repeat the macro indefinitely (until it gets an error). If you want to perform an operation on each line, then either you should start by positioning point on the line above the first one to be processed and then begin the macro definition with a C-N, or you should start on the proper line and end with a C-N. Either way, repeating the macro will operate on successive lines. >>> Place the cursor at the top of the screen and then enter the commands below. Note that after the first command, "Def" appears in the mode line. C-X ( C-A ***** M-F M-F M-F ----- C-N C-X ) >>> Notice that as you typed those commands in, they were executed. Now move the cursor down a couple of lines, but keep it near the top of the screen. Type the command C-U C-X E. This will execute your macro 4 times. Although not described here, it is possible to both name your macros, and to save and restore them from files. See the documentation for this. INITIALIZATION FILES -------------------- You can initialize JOVE just the way you like it by putting a file named ".joverc" in your home directory. To see what this file should look like, look at the one in the directory /usr/src/local/jove/doc. The file system.rc is one such file, the other example is example.rc. It should be noted that the commands in this file contain control characters, which may make it hard to read. Use the "cat -v" command for this. To insert control characters into a file with JOVE, you should use the C-Q command. Type C-Q <X> where <X> is the control character. Note that C-Q will not work on some terminals, because it, like C-S, is used for suspending and restoring the output to the terminal. In that case, use the command M-X quo <space> <X>. INTERACTIVE SHELLS ------------------ One of JOVE's very powerful features is the ability to start up shells within the editor, and then use shell commands within the screen editing environment. To execute a command again, just cursor-up to it, change it if you want with all the normal editing keys, and hit RETURN once to bring it down to your present command line, and again to execute it. We'll bow out here suggesting you consult the manual for hard details, or type M-X shell <space> if you are the adventurous type! CONCLUSION ---------- Remember, to exit use C-X C-C. This tutorial is meant to be understandable to all new users, so if you found something unclear, don't sit and blame yourself - complain! You'll probably find that if you use JOVE for a few days you won't be able to give it up. Initially it may give you trouble. But remember that this is the case with any editor, especially one that can do many, many things. And JOVE can do practically everything. Hopefully you have enjoyed this tutorial, and, more importantly, I hope you've learned something. If you use JOVE for about a week, and be patient, you will find that it is more convenient and friendly to use than any other editor you've used. I know. I did. --------------------------------------------------------------------------- This tutorial was originally written by Richard Stallman for EMACS and modified by Doug Kingston and Jonathan Payne for JOVE. The section on windows was added at UofT by Mark Moraes. Comments on this document should be sent to jpayne@cs.rochesteredu. (12 February '86), or locally (at UofT), to moraes@cga.toronto.edu.