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From: paul@cgh.UUCP (Paul Homchick) Newsgroups: comp.sources.misc Subject: MicroEmacs 3.8i Documentation (Formatted) 1 of 2 Message-ID: <2763@ncoast.UUCP> Date: 3 Jul 87 00:10:53 GMT Sender: allbery@ncoast.UUCP Lines: 2120 Approved: allbery@ncoast.UUCP X-Archive: comp.sources.misc/8707/3 MicroEmacs 3.8i Documentation formatted from MicroSCRIBE original. +++ Part One of Two +++ (Differs from the original uEmacs distribution by fixing some spelling errors and formattating problems) -----snip-----snip-----snip-----snip-----snip-----snip-----snip-----snip----- MicroEMACS Full Screen Text Editor Reference Manual (preliminary draft) Version 3.8i April 27, 1987 (C)opyright 1987 by Daniel M. Lawrence Reference Manual (C)opyright 1987 by Brian Straight and Daniel M. Lawrence All Rights Reserved MicroEMACS 3.8i can be copied and distributed freely for any non-commercial purposes. MicroEMACS 3.8i can only be incorporated into commercial software with the permission of the current author. Introduction MicroEMACS is a tool for creating and changing documents, programs, and other text files. It is both relatively easy for the novice to use, but also very powerful in the hands of an expert. MicroEMACS can be extensively customized for the needs of the individual user. MicroEMACS allows several files to be edited at the same time. The screen can be split into different windows, and text may be moved freely from one window to the next. Depending on the type of file being edited, MicroEMACS can change how it behaves to make editing simple. Editing standard text files, program files and word processing documents are all possible at the same time. There are extensive capabilities to make word processing and editing easier. These include commands for string searching and replacing, paragraph reformatting and deleting, automatic word wrapping, word move and deletes, easy case controlling, and automatic word counts. For complex and repetitive editing tasks editing macros can be written. These macros allow the user a great degree of flexibility in determining how MicroEMACS behaves. Also any and all the commands can be used by any keystroke by changing, or rebinding, what commands various keys are connected, or bound, to. Special features are also available to perform a diverse set of operations such as file encryption, automatic backup file generation, entabbing and detabbing lines, executing of DOS commands and filtering of text through other programs (like SORT to allow sorting text). History EMACS was originally a text editor written by Richard Stahlman at MIT in the early 1970s for Digital Equipment computers. Various versions, rewrites and clones have made an appearance since. This version of MicroEMACS is derived from code written by Dave G. Conroy in 1985. Later modifications were performed by Steve Wilhite and George Jones. In December of 1985 Daniel Lawrence picked up the then current source (version 2.0) and has made extensive modifications and additions to it over the course of the next two years. Updates and support for the current version is still in progress. The current program author can be contacted by writing to: USMAIL: Daniel Lawrence 617 New York St Lafayette, IN 47901 UUCP: ihnp4!pur-ee!pur-phy!duncan!lawrence ARPA: nwd@j.cc.purdue.edu FIDO: Fido 201/2 The Programmer's Room (317) 742-5533 MicroEMACS Reference Manual Basic Concepts Chapter 1 Basic Concepts The current version of MicroEMACS is 3.8i (Third major re-write, eighth public release, Ith (or ninth) minor release), and for the rest of this document, we shall simply refer to this version as "EMACS". Any modifications for later versions will be listed in the appendixes at the end of this manual. 1.1 Keys and the Keyboard Many times throughout this manual we will be talking about commands and the keys on the keyboard needed use them. There are a number of "special" keys which can be used and are listed here: <NL> NewLine which is also called RETURN or ENTER, this key is used to end different commands. ^ The control key can be used before any alphabetic character and some symbols. For example, ^C means to hold down the <CONTROL> key and type the C key at the same time. ^X The CONTROL-X key is used at the beginning of many different commands. META or M- This is a special EMACS key used to begin many commands as well. This key is pressed, and then released before typing the next character. On most systems, this is the <ESC> key, but it can be changed. (consult appendix D to learn what key is used for META on your computer). Whenever a command is described, the manual will list the actual keystrokes needed to execute it in boldface using the above conventions, and also the name of the command in italics. 1.2 Getting Started In order to use EMACS, you must call it up from your system's or computer's command prompt. On UNIX and MSDOS machines, just type "emacs" from the main command prompt and follow it with the <RETURN> or 1 Basic Concepts MicroEMACS Reference Manual <ENTER> key (we will refer to this key as <NL> for "new-line" for the remainder of this manual). On the Macintosh, the Amiga, the ATARI ST and other icon based operating systems, double click on the uEMACS icon. Shortly after this, a screen similar to the one below should appear. 1.3 Parts and Pieces The screen is divided into a number of areas or windows. On some systems the top window contains a function list of unshifted and shifted function keys. We will discuss these keys later. Below them is an EMACS mode line which, as we will see, informs you of the present mode of operation of the editor--for example "(WRAP)" if you set EMACS to wrap at the end of each line. Under the mode line is the text window where text appears and is manipulated. Since each window has its own mode line, below the text window is it's mode line. The last line of the screen is the command line where EMACS takes commands and reports on what it is doing. =============================================================================== f1 search f2 search back : F1 toggle function list F2 toggle help file f3 hunt f4 hunt back : F3 find command/apropos F4 describe key f5 next window f6 exec macro : F5 reformat paragraph F6 ref undented region f7 find file f8 exec file : F7 indent region F8 undent region f9 save file f10 exit emacs : F9 execute DOS command F10 shell up =============================================================================== -- MicroEMACS 3.8i () -- Function Keys --------------------------------------- =============================================================================== =============================================================================== -- MicroEMACS 3.8i () -- Main ------------------------------------------------ =============================================================================== Fig 1: EMACS screen on an IBM-PC 1.4 Entering Text Entering text in EMACS is simple. Type the following sentence fragment: Fang Rock lighthouse, center of a series of mysterious and 2 MicroEMACS Reference Manual Basic Concepts The text is displayed at the top of the text window. Now type: terrifying events at the turn of the century Notice the text to the left of the cursor disappears and a '$' sign appears. Don't panic--your text is safe!!! You've just discovered that EMACS doesn't "wrap" text to the next line like most word processors unless you hit <NL>. But since EMACS is used for both word processing, and text editing, it has a bit of a dual personality. You can change the way it works by setting various modes. In this case, you need to set WRAP mode, using the add-mode command, by typing ^X-M. The command line at the base of the screen will prompt you for the mode you wish to add. Type wrap followed by the <NL> key and any text you now enter will be wrapped. However, the command doesn't wrap text already entered. To get rid of the truncated line, delete characters with the <BACKSPACE> key until the '$' goes away. Now type in the words you deleted, watch how EMACS goes down to the next line at the right time. (In some versions of EMACS, WRAP is a default mode in which case you don't have to worry about the instructions relating to adding this mode.) Now let's type a longer insert. Hit <NL> a couple of times to tab down from the text you just entered. Now type the following paragraphs. Press <NL> twice to indicate a paragraph break. Fang Rock lighthouse, center of a series of mysterious and terrifying events at the turn of the century, is built on a rocky island a few miles of the Channel coast. So small is the island that wherever you stand its rocks are wet with sea spray. The lighthouse tower is in the center of the island. A steep flight of steps leads to the heavy door in its base. Winding stairs lead up to the crew room. 1.5 Basic cursor movement Now let's practice moving around in this text. To move the cursor back to the word "Winding," enter M-B previous-word. This command moves the cursor backwards by one word at a time. Note you have to press the key combination every time the cursor steps back by one word. Continuously pressing META and toggling B produces an error message. To move forward to the word "stairs" enter M-F, which moves the cursor forward by one word at a time. Notice that EMACS commands are usually mnemonic--F for forward, B for backward, for example. To move the cursor up one line, enter ^P previous-line, down one line ^N next-line. Practice this movement by moving the cursor to the word "terrifying" in the second line. 3 Basic Concepts MicroEMACS Reference Manual The cursor may also be moved forward or backward in smaller increments. To move forward by one character, enter ^F forward- character, to move backward, ^B backward-character. EMACS also allows you to specify a number which is normally used to tell a command to execute many times. To repeat most commands, press META and then the number before you enter the command. Thus, the command META 5 ^F (M-5^F) will move the cursor forward by five characters. Try moving around in the text by using these commands. For extra practice, see how close you can come to the word "small" in the first paragraph by giving an argument to the commands listed here. Two other simple cursor commands that are useful to help us move around in the text are M-N next-paragraph which moves the cursor to the second paragraph, and M-P previous-paragraph which moves it back to the previous paragraph. The cursor may also be moved rapidly from one end of the line to the other. Move the cursor to the word "few" in the second line. Press ^A beginning-of-line. Notice the cursor moves to the word "events" at the beginning of the line. Pressing ^E end-of-line moves the cursor to the end of the line. Finally, the cursor may be moved from any point in the file to the end or beginning of the file. Entering M-> end-of-file moves the cursor to the end of the buffer, M-< beginning-of-file to the first character of the file. On the IBM-PC, the ATARI ST and many other machines, the cursor keys can also be used to move the cursor about. Also, if there is one available, moving the mouse will move the cursor. Practice moving the cursor in the text until you are comfortable with the commands we've explored in this chapter. 1.6 Saving your text When you've finished practicing cursor movement, save your file. Your file currently resides in a BUFFER. The buffer is a temporary storage area for your text, and is lost when the computer is turned off. You can save the buffer to a file by entering ^X-^S save-file. Notice that EMACS informs you that your file has no name and will not let you save it. To save your buffer to a file with a different name than it's current one (which is empty), press ^X^W write-file. EMACS will prompt you for the filename you wish to write. Enter the name fang.txt and press return. On a micro, the drive light will come on, and EMACS will inform you it is writing the file. When it finishes, it will inform you of the number of lines it has written to the disk. Congratulations!! You've just saved your first EMACS file! 4 MicroEMACS Reference Manual Basic Concepts Chapter 1 Summary In chapter 1, you learned how to enter text, how to use wrap mode, how to move the cursor, and to save a buffer. The following is a table of the commands covered in this chapter and their corresponding key bindings: Key Binding Keystroke Effect abort-command ^G aborts current command add-mode ^XM allows addition of EMACS mode such as WRAP backward-character ^B moves cursor left one character beginning-of-file M-< moves cursor to beginning of file beginning-of-line ^A moves cursor to beginning of line end-of-file M-> moves cursor to end of file end-of-line ^E moves cursor to end of line forward-character ^F moves cursor right one character next-line ^N moves cursor to next line next-paragraph M-N moves cursor to next paragraph next-word M-F moves cursor forward one word previous-line ^P moves cursor backward by one line previous-paragraph M-P moves cursor to previous paragraph previous-word M-B moves cursor backward by one word save-file ^X-^S saves current buffer to a file write-file ^X-^W save current buffer under a new name 5 Basic Editing--Simple Insertions and Deletions MicroEMACS Reference Manual Chapter 2 Basic Editing--Simple Insertions and Deletions 2.1 A Word About Windows, Buffers, Screens, and Modes In the first chapter, you learned how to create and save a file in EMACS. Let's do some more editing on this file. Call up emacs by typing in the following command. emacs fang.txt On icon oriented systems, double click on the uEMACS icon, usually a file dialog box of some sort will appear. Choose FANG.TXT from the appropriate folder. Shortly after you invoke EMACS, the text should appear on the screen ready for you to edit. The text you are looking at currently resides in a buffer. A buffer is a temporary area of computer memory which is the primary unit internal to EMACS -- this is the place where EMACS goes to work. The mode line at the bottom of the screen lists the buffer name, FANG.TXT and the name of the file with which this buffer is associated, FANG.TXT The computer talks to you through the use of its screen. This screen usually has an area of 24 lines each of 80 characters across. You can use EMACS to subdivide the screen into several separate work areas, or windows, each of which can be 'looking into' different files or sections of text. Using windows, you can work on several related texts at one time, copying and moving blocks of text between windows with ease. To keep track of what you are editing, each window is identified by a mode line on the last line of the window which lists the name of the buffer which it is looking into, the file from which the text was read, and how the text is being edited. An EMACS mode tells EMACS how to deal with user input. As we have already seen, the mode 'WRAP' controls how EMACS deals with long lines (lines with over 79 characters) while the user is typing them in. The 'VIEW' mode, allows you to read a file without modifying it. Modes are associated with buffers and not with files; hence, a mode needs to be explicitly set or removed every time you edit a file. A new file read into a buffer with a previously specified mode will be edited under this mode. If you use specific modes frequently, EMACS allows you to set the modes which are used by all new buffers, called global modes. 6 MicroEMACS Reference Manual Basic Editing--Simple Insertions and Deletions 2.2 Insertions Your previously-saved text should look like this: Fang Rock lighthouse, center of a series of mysterious and terrifying events at the turn of the century, is built on a rocky island a few miles of the Channel coast. So small is the island that wherever you stand its rocks are wet with sea spray. The lighthouse tower is in the center of the island. A steep flight of steps leads to the heavy door in its base. Winding stairs lead up to the crew room. Let's assume you want to add a sentence in the second paragraph after the word "base." Move the cursor until it is on the "W" of "Winding". Now type the following: This gives entry to the lower floor where the big steam generator throbs steadily away, providing power for the electric lantern. If the line fails to wrap and you end up with a '$' sign in the right margin, just enter M-Q fill-paragraph to reformat the paragraph. This new command attempts to fill out a paragraph. Long lines are divided up, and words are shuffled around to make the paragraph look nicer. Notice that all visible EMACS characters are self-inserting -- all you had to do was type the characters to insert and the existing text made space for it. With a few exceptions discussed later, all non- printing characters (such as control or escape sequences) are commands. To insert spaces, simply use the space bar. Now move to the first line of the file and type ^O open-line (Oh, not zero). You've just learned how to insert a blank line in your text. 2.3 Deletions EMACS offers a number of deletion options. For example, move the cursor until it's under the period at the end of the insertion you just did. Press the backspace key. Notice the "n" on "lantern" disappeared. The backspace implemented on EMACS is called a destructive backspace--it removes text immediately before the current cursor position from the buffer. Now type ^H delete-previous-character. Notice that the cursor moves back and obliterates the "r"--either command will backspace the cursor. Type in the two letters you erased to restore your text and move the cursor to the beginning of the buffer M-> beginning-of-file. Move the cursor down one line to the beginning of the first paragraph. 7 Basic Editing--Simple Insertions and Deletions MicroEMACS Reference Manual To delete the forward character, type ^D delete-next-character. The "F" of "Fang" disappears. Continue to type ^D until the whole word is erased EMACS also permits the deletion of larger elements of text. Move the cursor to the word "center" in the first line of text. Pressing M-<backspace> delete-previous-word kills the word immediately before the cursor. M-^H has the same effect. Notice that the commands are very similar to the control commands you used to delete individual letters. As a general rule in EMACS, control sequences affect small areas of text, META sequences larger areas. The word forward of the cursor position can therefore be deleted by typing M-D delete-next-word. Now let's take out the remainder of the first line by typing ^K kill-to-end-of-line. You now have a blank line at the top of your screen. Typing ^K again or ^X-^O delete-blank-lines deletes the blank line and flushes the second line to the top of the text. Now exit EMACS by typing ^X-^C exit-emacs. Notice EMACS reminds you that you have not saved your buffer. Ignore the warning and exit. This way you can exit EMACS without saving any of the changes you just made. Chapter 2 Summary In Chapter 2, you learned about the basic 'building blocks' of an EMACS text file--buffers, windows, and files. Key binding Keystroke Effect delete-previous-character ^H deletes character immediately before the current cursor position delete-next-character ^D deletes character immediately after current cursor position delete-previous-word M-^H deletes word immediately before current cursor position delete-next-word M-D deletes word immediately after current cursor position kill-to-end-of-line ^K deletes from current cursor position to end of line insert-space ^C inserts a space to right of cursor open-line ^O inserts blank line delete-blank-lines ^X-^O removes blank line exit-emacs ^X-^C exits emacs 8 MicroEMACS Reference Manual Using Regions Chapter 3 Using Regions 3.1 Defining and Deleting a Region At this point its time to familiarize ourselves with two more EMACS terms--the point and the mark. The point is located directly behind the current cursor position. The mark (as we shall see shortly) is user defined. These two elements together are called the current region and limit the region of text on which EMACS performs many of its editing functions. Let's begin by entering some new text. Don't forget to add wrap mode if its not set on this buffer. Start EMACS and open a file called PUBLISH.TXT. Type in the following text: One of the largest growth areas in personal computing is electronic publishing. There are packages available for practically every machine from elegantly simple programs for the humble Commodore 64 to sophisticated professional packages for PC and Macintosh computers. Electronic publishing is as revolutionary in its way as the Gutenburg press. Whereas the printing press allowed the mass production and distribution of the written word, electronic publishing puts the means of production in the hands of nearly every individual. From the class magazine to the corporate report, electronic publishing is changing the way we produce and disseminate information. Personal publishing greatly increases the utility of practically every computer. Thousands of people who joined the computer revolution of this decade only to hide their machines unused in closets have discovered a new use for them as dedicated publishing workstations. Now let's do some editing. The last paragraph seems a little out of place. To see what the document looks like without it we can cut it from the text by moving the cursor to the beginning of the paragraph. Enter M-<space> set-mark. EMACS will respond with "[Mark set]". Now move the cursor to the end of the paragraph. You have just defined a region of text. To remove this text from the screen, type ^W kill- region. The paragraph disappears from the screen. 9 Using Regions MicroEMACS Reference Manual On further consideration, however, perhaps the paragraph we cut wasn't so bad after all. The problem may have been one of placement. If we could tack it on to the end of the first paragraph it might work quite well to support and strengthen the argument. Move the cursor to the end of the first paragraph and enter ^Y yank. Your text should now look like this: One of the largest growth areas in personal computing is electronic publishing. There are packages available for practically every machine from elegantly simple programs for the humble Commodore 64 to sophisticated professional packages for PC and Macintosh computers. Personal publishing greatly increases the utility of practically every computer. Thousands of people who joined the computer revolution of this decade only to hide their machines unused in closets have discovered a new use for them as dedicated publishing workstations. Electronic publishing is as revolutionary in its way as the Gutenburg press. Whereas the printing press allowed the mass production and distribution of the written word, electronic publishing puts the means of production in the hands of nearly every individual. From the class magazine to the corporate report, electronic publishing is changing the way we produce and disseminate information. 3.2 Yanking a Region The text you cut initially didn't simply just disappear, it was cut into a buffer that retains the 'killed' text appropriately called the kill buffer. ^Y "yanks" the text back from this buffer into the current buffer. If you have a long line (indicated, remember, by the "$" sign), simply hit M-Q to reformat the paragraph. There are other uses to which the kill buffer can be put. Using the method we've already learned, define the last paragraph as a region. Now type M-W copy-region. Nothing seems to have happened; the cursor stays blinking at the point. But things have changed, even though you may not be able to see any alteration. To see what has happened to the contents of the kill buffer, move the cursor down a couple of lines and "yank" the contents of the kill buffer back with ^Y. Notice the last paragraph is now repeated. The region you defined is "tacked on" to the end of your file because M- W copies a region to the kill buffer while leaving the original text in your working buffer. Some caution is needed however, because the contents of the kill buffer are updated when you delete any regions, lines or words. If you are moving large quantities of text, complete the operation before you do any more deletions or you could find that the text you want to move has been replaced by the most recent deletion. Remember--a buffer is a temporary area of computer memory that is lost when the machine is powered down or switched off. In order to make your 10 MicroEMACS Reference Manual Using Regions changes permanent, they must be saved to a file before you leave EMACS. Let's delete the section of text we just added and save the file to disk. Chapter 3 Summary In Chapter 3, you learned how to achieve longer insertions and deletions. The EMACS terms point and mark were introduced and you learned how to manipulate text with the kill buffer. Key Binding Keystroke Effect Delete-Region ^W Deletes region between point and mark and places it in KILL buffer Copy-Region M-W Copies text between point and mark into KILL buffer Yank-Text ^Y Inserts a copy of the KILL buffer into current buffer at point 11 Search and Replace MicroEMACS Reference Manual Chapter 4 Search and Replace 4.1 Forward Search Load EMACS and bring in the file you just saved. Your file should look like the one below. One of the largest growth areas in personal computing is electronic publishing. There are packages available for practically every machine from elegantly simple programs for the humble Commodore 64 to sophisticated professional packages for PC and Macintosh computers. Personal publishing greatly increases the utility of practically every computer. Thousands of people who joined the computer revolution of this decade only to hide their machines unused in closets have discovered a new use for them as dedicated publishing workstations. Electronic publishing is as revolutionary in its way as the Gutenburg press. Whereas the printing press allowed the mass production and distribution of the written word, electronic publishing puts the means of production in the hands of nearly every individual. From the class magazine to the corporate report, electronic publishing is changing the way we produce and disseminate information. Let's use EMACS to search for the word "revolutionary" in the second paragraph. Because EMACS searches from the current cursor position toward the end of buffers, and we intend to search forward, move the cursor to the beginning of the text. Enter ^S search-forward. Note that the command line now reads "Search [] <META>:" EMACS is prompting you to enter the search string -- the text you want to find. Enter the word revolutionary and hit the META key. The cursor moves to the end of the word "revolutionary." Notice that you must enter the <META> key to start the search. If you simply press <NL> the command line responds with "<NL>". Although this may seem infuriating to users who are used to pressing the return key to execute any command, EMACS' use of <META> to begin searches allows it to pinpoint text with great accuracy. After every line wrap or carriage return, EMACS 'sees' a new line character (<NL>). 12 MicroEMACS Reference Manual Search and Replace If you need to search for a word at the end of a line, you can specify this word uniquely in EMACS. In our sample text for example, the word "and" occurs a number of times, but only once at the end of a line. To search for this particular occurrence of the word, move the cursor to the beginning of the buffer and type ^S. Notice that EMACS stores the last specified search string as the default string. If you press <META> now, EMACS will search for the default string, in this case, "revolutionary." To change this string so we can search for our specified "and" simply enter the word and followed by <NL>. The command line now shows: "search [and<NL>]<META>:" Press <META> and the cursor moves to "and" at the end of the second last line. 4.2 Exact Searches If the mode EXACT is active in the current buffer, EMACS searches on a case sensitive basis. Thus, for example you could search for Publishing as distinct from publishing. 4.3 Backward Search Backward searching is very similar to forward searching except that it is implemented in the reverse direction. To implement a reverse search, type ^R search-reverse. Because EMACS makes no distinction between forward and backward stored search strings, the last search item you entered appears as the default string. Try searching back for any word that lies between the cursor and the beginning of the buffer. Notice that when the item is found, the point moves to the beginning of the found string (i.e., the cursor appears under the first letter of the search item). Practice searching for other words in your text. 4.4 Searching and Replacing Searching and replacing is a powerful and quick way of making changes to your text. Our sample text is about electronic publishing, but the correct term is 'desktop' publishing. To make the necessary changes we need to replace all occurrences of the word "electronic" with "desktop." First, move the cursor to the top of the current buffer with the M-< command. Then type M-R replace-string. The command line responds: 13 Search and Replace MicroEMACS Reference Manual "Replace []<META>:" where the square brackets enclose the default string. Type the word electronic and hit <META>. The command line responds: "with []<META>" type desktop<META>. EMACS replaces all instances of the original word with your revision. Of course, you will have to capitalize the first letter of "desktop" where it occurs at the beginning of a sentence. You have just completed an unconditional replace. In this operation, EMACS replaces every instance of the found string with the replacement string. 4.5 Query-Replace You may also replace text on a case by case basis. The M-^R query-replace-string command causes EMACS to pause at each instance of the found string. For example, assume we want to replace some instances of the word "desktop" with the word "personal." Go back to the beginning of the current buffer and enter the M-^R query-replace command. The procedure is very similar to that which you followed in the unconditional search/replace option. When the search begins however, you will notice that EMACS pauses at each instance of "publishing" and asks whether you wish to replace it with the replacement string. You have a number of options available for response: Response Effect Y(es) Make the current replacement and skip to the next occurrence of the search string N(o) Do not make this replacement but continue ! Do the rest of the replacements with no more queries U(ndo) Undo just the last replacement and query for it again (This can only go back ONE time) ^G Abort the replacement command (This action does not undo previously-authorized replacements . Same effect as ^G, but cursor returns to the point at which the replacement command was given ? This lists help for the query replacement command Practice searching and searching and replacing until you feel comfortable with the commands and their effects. 14 Windows MicroEMACS Reference Manual Chapter 4 Summary In this chapter, you learned how to search for specified strings of text in EMACS. The chapter also dealt with searching for and replacing elements within a buffer. Key Binding Keystroke Effect Search-Forward ^S Searches from point to end of buffer. Point is moved from current location to the end of the found string Search-Backward ^R Searches from point to beginning of buffer. Point is moved from current location to beginning of found string Replace M-R Replace ALL occurrences of search string with specified (null) string from point to the end of the current buffer Query-Replace M-^R As above, but pause at each found string and query for action 16 MicroEMACS Reference Manual Windows Chapter 5 Windows 5.1 Creating Windows We have already met windows in an earlier chapter. In this chapter, we will explore one of EMACS' more powerful features -- text manipulation through multiple windowing. You will recall that windows are areas of buffer text that you can see on the screen. Because EMACS can support several screen windows simultaneously you can use them to look into different places in the same buffer. You can also use them to look at text in different buffers. In effect, you can edit several files at the same time. Let's invoke EMACS and pull back our file on desktop publishing by typing emacs publish.txt When the text appears, type the ^X-2 split-current-window command. The window splits into two windows. The window where the cursor resides is called the current window -- in this case the bottom window. Notice that each window has a text area and a mode line. The command line is however, common to all windows on the screen. The two windows on your screen are virtually mirror images of each other because the new window is opened into the same buffer as the one you are in when you issue the Open-Window command. All commands issued to EMACS are executed on the current buffer in the current window. To move the cursor to the upper window (i.e., to make that window the current window, type ^X-P previous-window. Notice the cursor moves to the upper or previous window. Entering ^X-O next-window moves to the next window. Practice moving between windows. You will notice that you can also move into the Function Key menu by entering these commands. Now move to the upper window. Let's open a new file. On the EMACS disk is a tutorial file. Let's call it into the upper window by typing: ^X-^F find-file 17 Windows MicroEMACS Reference Manual and press return. Then enter the filename emacs.tut. In a short time, the tutorial file will appear in the window. We now have two windows on the screen, each looking into different buffers. We have just used the ^X- ^F find-file command to find a file and bring it into our current window. You can scroll any window up and down with the cursor keys, or with the commands we've learned so far. However, because the area of visible text in each window is relatively small, you can scroll the current window a line at a time. Type ^X-^N move-window-down The current window scrolls down by one line -- the top line of text scrolls out of view, and the bottom line moves towards the top of the screen. You can imagine, if you like, the whole window slowly moving down to the end of the buffer in increments of one line. The command ^X-^P move-window-up scrolls the window in the opposite direction. As we have seen, EMACS editing commands are executed in the current window, but the program does support a useful feature that allows you to scroll the next window. M-^Z scroll-next-up scrolls the next window up, M-^U scroll-next-down scrolls it downward. From the tutorial window, practice scrolling the window with the desktop publishing text in it up and down. When you're finished, exit EMACS without saving any changes in your files. Windows offer you a powerful and easy way to edit text. By manipulating a number of windows and buffers on the screen simultaneously, you can perform complete edits and revisions on the computer screen while having your draft text or original data available for reference in another window. Experiment with splitting the windows on your screen. Open windows into different buffers and experiment with any other files you may have. Try editing the text in each window, but don't forget to save any changes you want to keep -- you still have to save each buffer separately. 5.2 Deleting Windows 5.3 Resizing Windows 5.4 Other Window commands 18 MicroEMACS Reference Manual Windows Chapter 5 Summary In Chapter 5 you learned how to manipulate windows and the editing flexibility they offer. Key Binding Keystroke Effect Open-Window ^X-2 Splits current window into two windows if space is available Close-Windows ^X-1 Closes all windows except current window Next-Window ^X-O Moves point into next (i.e. downward) window Previous-Window ^X-P Moves point to previous (i.e. upward) window Move-Window-Down ^X-^N Scrolls current window down one line Move-Window-Up ^X-^P Scrolls current window up one line Redraw-display M-! or Window is moved so line with point M-^L (with cursor) is at center of window Grow-Window ^X-^ Current window is enlarged by one line and nearest window is shrunk by one line Shrink-Window ^X-^Z Current window is shrunk by one line and nearest window is enlarged by one line Clear-and-Redraw ^L Screen is blanked and redrawn. Keeps screen updates in sync with your commands Scroll-Next-Up M-^Z Scrolls next window up by one line Scroll-Next-Down M-^U Scrolls next window down by one line 19 Buffers MicroEMACS Reference Manual Chapter 6 Buffers We have already learned a number of things about buffers. As you will recall, they are the major internal entities in EMACS -- the place where editing commands are executed. They are characterized by their names, their modes, and by the file with which they are associated. Each buffer also "remembers" its mark and point. This convenient feature allows you to go to other buffers and return to the original location in the "current" buffer. Advanced users of EMACS frequently have a number of buffers in the computer's memory simultaneously. In the last chapter, for example, you opened at least two buffers -- one into the text you were editing, and the other into the EMACS on-line tutorial. If you deal with complex text files -- say, sectioned chapters of a book, you may have five or six buffers in the computer's memory. You could select different buffers by simply calling up the file with ^X-^F find-file, and let EMACS open or reopen the buffer. However, EMACS offers fast and sophisticated buffering techniques that you will find easy to master and much more convenient to use. Let's begin by opening three buffers. You can open any three you choose, for example call the following files into memory: fang.txt, publish.txt, and emacs.tut in the order listed here. When you've finished this process, you'll be looking at a screen showing the EMACS tutorial. Let's assume that you want to move to the fang.txt buffer. Enter: ^X-X next-buffer This command moves you to the next buffer. Because EMACS cycles through the buffer list, which is alphabetized, you will now be in the fang.txt buffer. Using ^X-X again places you in the publish.txt buffer. If you are on a machine that supports function keys, using ^X-X again places you in the Function Keys buffer. Using ^X-X one last time cycles you back to the beginning of the list. If you have a large number of buffers to deal with, this cycling process may be slow and inconvenient. The command ^X-B select-buffer allows you to specify the buffer you wish to be switched to. When the command is entered, EMACS prompts, "Use buffer:". Simply enter the buffer name (NOT the file name), and that buffer will then become the current buffer. 20 MicroEMACS Reference Manual Buffers Multiple buffer manipulation and editing is a complex activity, and you will probably find it very inconvenient to re-save each buffer as you modify it. The command ^X-^B list-buffers creates a new window that gives details about all the buffers currently known to EMACS. Buffers that have been modified are identified by the "buffer changed" indicator (an asterisk in the second column). You can thus quickly and easily identify buffers that need to be saved to files before you exit EMACS. The buffer window also provides other information -- buffer specific modes, buffer size, and buffer name are also listed. To close this window, simply type the close-windows command, ^X-1. To delete any buffer, type ^X-K delete-buffer. EMACS prompts you "Kill buffer:". Enter the buffer name you want to delete. As this is destructive command, EMACS will ask for confirmation if the buffer was changed and not saved. Answer Y(es) or N(o). As usual ^G cancels the command. 21 Buffers MicroEMACS Reference Manual Chapter 6 Summary In Chapter 6 you learned how to manipulate buffers. Key Binding Keystroke Effect Next-Buffer ^X-^X Switch to the next buffer in the buffer list Select-Buffer ^X-B Switch to a particular buffer List-Buffers ^X-^B List all buffers Delete-Buffer ^X-K delete a particular buffer if it is off-screen 22 MicroEMACS Reference Manual Modes Chapter 7 Modes EMACS allows you to change the way it works in order to customized it to the style of editing you are using. It does this by providing a number of different modes. These modes can effect either a single buffer, or any new buffer that is created. To add a mode to the current buffer, type ^X-M add-mode. EMACS will then prompt you for the name of a mode to add. When you type in a legal mode name, and type a <NL>, EMACS will add the mode name to the list of current mode names in the mode line of the current buffer. To remove an existing mode, typing the ^X-^M delete-mode will cause EMACS to prompt you for the name of a mode to delete from the current buffer. This will remove that mode from the mode list on the current mode line. Global modes are the modes which are inherited by any new buffers which are created. For example, if you wish to always do string searching with character case being significant, you would want global mode EXACT to be set so that any new files read in inherent the EXACT mode. Global modes are set with the M-M add-global-mode command, and unset with the M-^M delete-global-mode command. Also, the current global modes are displayed in the first line of a ^X-^B list-buffers command. On machines which are capable of displaying colors, the mode commands can also set the background and foreground character colors. Using add-mode or delete-mode with a lowercase color will set the background color in the current window. An uppercase color will set the foreground color in the current window. Colors that EMACS knows about are: white, cyan, magenta, yellow, blue, red, green, and black. If the computer you are running on does not have eight colors, EMACS will attempt to make some intelligent guess at what color to use when you ask for one which is not there. 7.1 ASAVE mode Automatic Save mode tells EMACS to automatically write out the current buffer to its associated file on a regular basis. Normally this will be every 256 characters typed into the file. The environment variable $ACOUNT counts down to the next auto-save, and $ASAVE is the value used to reset $ACOUNT after a save occurs. 23 Modes MicroEMACS Reference Manual 7.2 CMODE mode CMODE is useful to C programmers. When CMODE is active, EMACS will try to assist the user in a number of ways. This mode is set automatically with files that have a .c or .h extension. The <NL> key will normally attempt to return the user to the next line at the same level of indentation as the current line, unless the current line ends with a open brace ({) in which case the new line will be further indented by one tab position. A close brace (}) will delete one tab position preceding itself as it is typed. This should line up the close brace with its matching IF, FOR or WHILE statement. A pound sign (#) with only leading whitespace will delete all the whitespace preceding itself. This will always bring preprocessor directives flush to the left margin. Whenever any close fence is typed, i.e )]>}, if the matching open fence is on screen in the current window, the cursor will briefly flash to it, and then back. This makes balancing expressions, and matching blocks much easier. 7.3 CRYPT mode When a buffer is in CRYPT mode, it is encrypted whenever it is written to a file, and decrypted when it is read from the file. The encryption key can be specified on the command line with the -k switch, or with the M-E set-encryption-key command. If you attempt to read or write a buffer in crypt mode and now key has not been set, EMACS will execute set-encryption-key automatically, prompting you for the needed key. Whenever EMACS prompts you for a key, it will not echo the key to your screen as you type it (i.e make SURE you get it right when you set it originally). The encryption algorithm used changes all characters into normal printing characters, thus the resulting file is suitable for sending via electronic mail. All version of MicroEMACS should be able decrypt the resulting file regardless of what machine encrypted it. Also available with EMACS is the stand alone program, MicroCRYPT, which can en/decrypt the files produced by CRYPT mode in EMACS. 7.4 EXACT mode All string searches and replacements will take upper/lower case into account. Normally the case of a string during a search or replace is not taken into account. 24 MicroEMACS Reference Manual Modes 7.5 MAGIC mode In the MAGIC mode certain characters gain special meanings when used in a search pattern. Collectively they are know as regular expressions, and a limited number of them are supported in MicroEmacs. They grant greater flexibility when using the search command. However, they do not affect the incremental search command. The symbols that have special meaning in MAGIC mode are ^, $, ., *, [ (and ], used with it), and \. The characters ^ and $ fix the search pattern to the beginning and end of line, respectively. The ^ character must appear at the beginning of the search string, and the $ must appear at the end, otherwise they loose their meaning and are treated just like any other character. For example, in MAGIC mode, searching for the pattern "t$" would put the cursor at the end of any line that ended with the letter 't'. Note that this is different than searching for "t<NL>", that is, 't' followed by a newline character. The character $ (and ^, for that matter) matches a position, not a character, so the cursor remains at the end of the line. But a newline is a character that must be matched, just like any other character, which means that the cursor is placed just after it - on the beginning of the next line. The character . has a very simple meaning -- it matches any single character, except the newline. Thus a search for "bad.er" could match "badger", "badder" (slang), or up to the 'r' of "bad error". The character * is known as closure, and means that zero or more of the preceding character will match. If there is no character preceding, * has no special meaning, and since it will not match with a newline, * will have no special meaning if preceded by the beginning of line symbol ^ or the literal newline character <NL>. The notion of zero or more characters is important. If, for example, your cursor was on the line This line is missing two vowels. and a search was made for "a*", the cursor would not move, because it is guaranteed to match no letter 'a' , which satisfies the search conditions. If you wanted to search for one or more of the letter 'a', you would search for "aa*", which would match the letter a, then zero or more of them. The character [ indicates the beginning of a character class. It is similar to the 'any' character ., but you get to choose which characters you want to match. The character class is ended with the character ]. So, while a search for "ba.e" will match "bane", "bade", "bale", "bate", et cetera, you can limit it to matching "babe" and "bake" by searching for "ba[bk]e". Only one of the characters inside the [ and ] will match a character. If in fact you want to match any character except those in the character class, you can put a ^ as the 25 Modes MicroEMACS Reference Manual first character. It must be the first character of the class, or else it has no special meaning. So, a search for [^aeiou] will match any character except a vowel, but a search for [aeiou^] will match any vowel or a ^. If you have a lot of characters in order that you want to put in the character class, you may use a dash (-) as a range character. So, [a-z] will match any letter (or any lower case letter if EXACT mode is on), and [0-9a-f] will match any digit or any letter 'a' through 'f', which happen to be the characters for hexadecimal numbers. If the dash is at the beginning or end of a character class, it is taken to be just a dash. The escape character \ is for those times when you want to be in MAGIC mode, but also want to use a regular expression character to be just a character. It turns off the special meaning of the character. So a search for "it\." will search for a line with "it.", and not "it" followed by any other character. The escape character will also let you put ^, -, or ] inside a character class with no special side effects. 7.6 OVER mode OVER mode stands for overwrite mode. When in this mode, when characters are typed, instead of simply inserting them into the file, EMACS will attempt to overwrite an existing character past the point. This is very useful for adjusting tables and diagrams. 7.7 WRAP mode Wrap mode is used when typing in continuous text. Whenever the cursor is past the currently set fill column (72 by default) and the user types a space or a <NL>, the last word of the line is brought down to the beginning of the next line. Using this, one just types a continuous stream of words and EMACS automatically inserts <NL>s at appropriate places. NOTE to programmers: EMACS actually calls up the function bound to the illegal keystroke M-FNW. This is bound to the function wrap-word by default, but can be re-bound to activate different functions and macros at wrap time. 7.8 VIEW mode VIEW mode disables all commands which can change the current buffer. EMACS will display an error message and ring the bell every time you attempt to change a buffer in VIEW mode. 26 MicroEMACS Reference Manual Modes Chapter 7 Summary In Chapter 7 you learned about modes and their effects. Key Binding Keystroke Effect Add-Mode ^X-M Add a mode to the current buffer Delete-Mode ^X-^M Delete a mode from the current buffer Add-Global-Mode M-M Add a global mode to the current buffer Delete-Global-Mode M-^M Delete a global mode from the current buffer 27 Files MicroEMACS Reference Manual Chapter 8 Files A file is simply a collection of related data. In EMACS we are dealing with text files -- named collections of text residing on a disk (or some other storage medium). You will recall that the major entities EMACS deals with are buffers. Disk-based versions of files are only active in EMACS when you are reading into or writing out of buffers. As we have already seen, buffers and physical files are linked by associated filenames. For example, the buffer "ch7.txt" which is associated with the physical disk file "ch7.txt." You will notice that the file is usually specified by the drive name or (in the case of a hard drive) a path. Thus you can specify full filenames in EMACS, e.g. disk:\directories\filename.extension If you do not specify a disk and directories, the default disk is used. IMPORTANT -- If you do not explicitly save your buffer to a file, all your edits will be lost when you leave EMACS (although EMACS will prompt you when you are about to lose edits by exiting). In addition, EMACS does not protect your disk-based files from overwriting when it saves files. Thus when you instruct EMACS to save a file to disk, it will create a file if the specified file doesn't exist, or it will overwrite the previously saved version of the file thus replacing it. Your old version is gone forever. If you are at all unsure about your edits, or if (for any reason) you wish to keep previous versions of a file, you can change the name of the associated file with the command ^X-N. When this file is saved to disk, EMACS will create a new physical file under the new name. The earlier disk file will be preserved. For example, let's load the file fang.txt into EMACS. Now, type ^X-N. The EMACS command line prompts "name:". Enter a new name for the file -- say new.txt and press <NL>. The file will be saved under the new filename, and your disk directory will show both fang.txt and new.txt. An alternative method is to write the file directly to disk under a new filename. Let's pull our "publish.txt" file into EMACS. To write this file under another filename, type ^X-^W. EMACS will prompt you "write file:". Enter an alternate filename -- desktop.txt. Your file will be saved as the physical file "desktop.txt". 28 MicroEMACS Reference Manual Files Note that in the examples above, although you have changed the names of the related files, the buffer names remain the same. However, when you pull the physical file back into EMACS, you will find that the buffer name now relates to the filename. For example -- You are working with a buffer "fang.txt" with the related file "fang.txt". You change the name of the file to "new.txt". EMACS now shows you working with the buffer "fang.txt" and the related file "new.txt". Now pull the file "new.txt" into EMACS. Notice that the buffer name has now changed to "new.txt". If for any reason a conflict of buffer names occurs,(if you have files of the same name on different drives for example) EMACS will prompt you "use buffer:". Enter an alternative buffer name if you need to. For a list of file related commands (including some we`ve already seen), see the summary page. 29 Files MicroEMACS Reference Manual Chapter 8 Summary In Chapter 8 you learned some of the more advanced concepts of file naming and manipulation. The relationship between files and buffers was discussed in some detail. Key Binding Keystroke Effect Save-file ^X-^S Saves contents of current buffer with associated filename on default disk/ directory (if not specified) Write-File ^X-^W Current buffer contents will be saved under specified name Change-File-name ^X-N The associated filename is changed (or associated if not previously specified) as specified Find-File ^X-^F Reads specified file into buffer and switches you to that buffer, or switches to buffer in which the file has previously been read Read-File ^X-^R Reads file into buffer thus overwriting buffer contents. If file has already been read into another buffer, you will be switched to it View-File ^X-^V The same as read-file except the buffer is automatically put into VIEW mode thus preventing any changes from being made 30 MicroEMACS Reference Manual Screen Formatting Chapter 9 Screen Formatting 9.1 Wrapping Text As we learned in the introduction, EMACS is not a word processor, but an editor. Some simple formatting options are available however, although in most cases they will not affect the appearance of the finished text when it is run through the formatter. We have already encountered WRAP mode which wraps lines longer than a certain length (default is 75 characters). You will recall that WRAP is enabled by entering ^X-M and responding to the command line prompt with wrap. You can also set your own wrap margin with the command ^X-F set- fill-column. Notice EMACS responds "[Fill column is 1]." Now try typing some text. You'll notice some very strange things happening -- your text wraps at every word!! This effect occurs because the set wrap margin command must be preceded by a numeric argument or EMACS sets it to the first column. Thus any text you type that extends past the first column will wrap at the most convenient line break. To reset the wrap column to 72 characters, press the <META> key and enter 72. EMACS will respond "Arg: 72". Now press ^X-F. EMACS will respond "[Fill column is 72]". Your text will again wrap at the margin you've been using up to this point. 9.2 Reformatting Paragraphs After an intensive editing session, you may find that you have paragraphs containing lines of differing lengths. Although this disparity will not affect the formatted text, aesthetic and technical concerns may make it desirable to have consistent paragraph blocks on the screen. If you are in WRAP mode, you can reformat a paragraph with the command M-Q fill-paragraph. This command 'fills' the current paragraph reformatting it so all the lines are filled and wrap logically. The process is complex, and (especially with longer paragraphs) may take a little time. 31 -----snip-----snip-----snip-----snip-----snip-----snip-----snip-----snip----- -- Paul Homchick Chimitt Gilman Homchick, Inc.; One Radnor Station, Suite 300; Radnor, PA 19087 {seismo!bpa | ihnp4!cbmvax} !vu-vlsi!cgh!paul