This is ../info/emacs, produced by makeinfo version 4.3 from emacs.texi. This is the Fourteenth edition of the `GNU Emacs Manual', updated for Emacs version 21.3. INFO-DIR-SECTION Emacs START-INFO-DIR-ENTRY * Emacs: (emacs). The extensible self-documenting text editor. END-INFO-DIR-ENTRY Published by the Free Software Foundation 59 Temple Place, Suite 330 Boston, MA 02111-1307 USA Copyright (C) 1985,1986,1987,1993,1994,1995,1996,1997,1998,1999,2000,2001,2002 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with the Invariant Sections being "The GNU Manifesto", "Distribution" and "GNU GENERAL PUBLIC LICENSE", with the Front-Cover texts being "A GNU Manual," and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled "GNU Free Documentation License." (a) The FSF's Back-Cover Text is: "You have freedom to copy and modify this GNU Manual, like GNU software. Copies published by the Free Software Foundation raise funds for GNU development."  File: emacs, Node: Rebinding, Next: Init Rebinding, Prev: Minibuffer Maps, Up: Key Bindings Changing Key Bindings Interactively ----------------------------------- The way to redefine an Emacs key is to change its entry in a keymap. You can change the global keymap, in which case the change is effective in all major modes (except those that have their own overriding local definitions for the same key). Or you can change the current buffer's local map, which affects all buffers using the same major mode. `M-x global-set-key KEY CMD ' Define KEY globally to run CMD. `M-x local-set-key KEY CMD ' Define KEY locally (in the major mode now in effect) to run CMD. `M-x global-unset-key KEY' Make KEY undefined in the global map. `M-x local-unset-key KEY' Make KEY undefined locally (in the major mode now in effect). For example, suppose you like to execute commands in a subshell within an Emacs buffer, instead of suspending Emacs and executing commands in your login shell. Normally, `C-z' is bound to the function `suspend-emacs' (when not using the X Window System), but you can change `C-z' to invoke an interactive subshell within Emacs, by binding it to `shell' as follows: M-x global-set-key C-z shell `global-set-key' reads the command name after the key. After you press the key, a message like this appears so that you can confirm that you are binding the key you want: Set key C-z to command: You can redefine function keys and mouse events in the same way; just type the function key or click the mouse when it's time to specify the key to rebind. You can rebind a key that contains more than one event in the same way. Emacs keeps reading the key to rebind until it is a complete key (that is, not a prefix key). Thus, if you type `C-f' for KEY, that's the end; the minibuffer is entered immediately to read CMD. But if you type `C-x', another character is read; if that is `4', another character is read, and so on. For example, M-x global-set-key C-x 4 $ spell-other-window redefines `C-x 4 $' to run the (fictitious) command `spell-other-window'. The two-character keys consisting of `C-c' followed by a letter are reserved for user customizations. Lisp programs are not supposed to define these keys, so the bindings you make for them will be available in all major modes and will never get in the way of anything. You can remove the global definition of a key with `global-unset-key'. This makes the key "undefined"; if you type it, Emacs will just beep. Similarly, `local-unset-key' makes a key undefined in the current major mode keymap, which makes the global definition (or lack of one) come back into effect in that major mode. If you have redefined (or undefined) a key and you subsequently wish to retract the change, undefining the key will not do the job--you need to redefine the key with its standard definition. To find the name of the standard definition of a key, go to a Fundamental mode buffer and use `C-h c'. The documentation of keys in this manual also lists their command names. If you want to prevent yourself from invoking a command by mistake, it is better to disable the command than to undefine the key. A disabled command is less work to invoke when you really want to. *Note Disabling::.  File: emacs, Node: Init Rebinding, Next: Function Keys, Prev: Rebinding, Up: Key Bindings Rebinding Keys in Your Init File -------------------------------- If you have a set of key bindings that you like to use all the time, you can specify them in your `.emacs' file by using their Lisp syntax. (*Note Init File::.) The simplest method for doing this works for ASCII characters and Meta-modified ASCII characters only. This method uses a string to represent the key sequence you want to rebind. For example, here's how to bind `C-z' to `shell': (global-set-key "\C-z" 'shell) This example uses a string constant containing one character, `C-z'. The single-quote before the command name, `shell', marks it as a constant symbol rather than a variable. If you omit the quote, Emacs would try to evaluate `shell' immediately as a variable. This probably causes an error; it certainly isn't what you want. Here is another example that binds a key sequence two characters long: (global-set-key "\C-xl" 'make-symbolic-link) To put , , , or in the string, you can use the Emacs Lisp escape sequences, `\t', `\r', `\e', and `\d'. Here is an example which binds `C-x ': (global-set-key "\C-x\t" 'indent-rigidly) These examples show how to write some other special ASCII characters in strings for key bindings: (global-set-key "\r" 'newline) ;; (global-set-key "\d" 'delete-backward-char) ;; (global-set-key "\C-x\e\e" 'repeat-complex-command) ;; When the key sequence includes function keys or mouse button events, or non-ASCII characters such as `C-=' or `H-a', you must use the more general method of rebinding, which uses a vector to specify the key sequence. The way to write a vector in Emacs Lisp is with square brackets around the vector elements. Use spaces to separate the elements. If an element is a symbol, simply write the symbol's name--no other delimiters or punctuation are needed. If a vector element is a character, write it as a Lisp character constant: `?' followed by the character as it would appear in a string. Here are examples of using vectors to rebind `C-=' (a control character not in ASCII), `C-M-=' (not in ASCII because `C-=' is not), `H-a' (a Hyper character; ASCII doesn't have Hyper at all), (a function key), and `C-Mouse-1' (a keyboard-modified mouse button): (global-set-key [?\C-=] 'make-symbolic-link) (global-set-key [?\M-\C-=] 'make-symbolic-link) (global-set-key [?\H-a] 'make-symbolic-link) (global-set-key [f7] 'make-symbolic-link) (global-set-key [C-mouse-1] 'make-symbolic-link) You can use a vector for the simple cases too. Here's how to rewrite the first three examples above, using vectors to bind `C-z', `C-x l', and `C-x ': (global-set-key [?\C-z] 'shell) (global-set-key [?\C-x ?l] 'make-symbolic-link) (global-set-key [?\C-x ?\t] 'indent-rigidly) (global-set-key [?\r] 'newline) (global-set-key [?\d] 'delete-backward-char) (global-set-key [?\C-x ?\e ?\e] 'repeat-complex-command) As you see, you represent a multi-character key sequence with a vector by listing each of the characters within the square brackets that delimit the vector.  File: emacs, Node: Function Keys, Next: Named ASCII Chars, Prev: Init Rebinding, Up: Key Bindings Rebinding Function Keys ----------------------- Key sequences can contain function keys as well as ordinary characters. Just as Lisp characters (actually integers) represent keyboard characters, Lisp symbols represent function keys. If the function key has a word as its label, then that word is also the name of the corresponding Lisp symbol. Here are the conventional Lisp names for common function keys: `left', `up', `right', `down' Cursor arrow keys. `begin', `end', `home', `next', `prior' Other cursor repositioning keys. `select', `print', `execute', `backtab' `insert', `undo', `redo', `clearline' `insertline', `deleteline', `insertchar', `deletechar' Miscellaneous function keys. `f1', `f2', ... `f35' Numbered function keys (across the top of the keyboard). `kp-add', `kp-subtract', `kp-multiply', `kp-divide' `kp-backtab', `kp-space', `kp-tab', `kp-enter' `kp-separator', `kp-decimal', `kp-equal' Keypad keys (to the right of the regular keyboard), with names or punctuation. `kp-0', `kp-1', ... `kp-9' Keypad keys with digits. `kp-f1', `kp-f2', `kp-f3', `kp-f4' Keypad PF keys. These names are conventional, but some systems (especially when using X) may use different names. To make certain what symbol is used for a given function key on your terminal, type `C-h c' followed by that key. A key sequence which contains function key symbols (or anything but ASCII characters) must be a vector rather than a string. The vector syntax uses spaces between the elements, and square brackets around the whole vector. Thus, to bind function key `f1' to the command `rmail', write the following: (global-set-key [f1] 'rmail) To bind the right-arrow key to the command `forward-char', you can use this expression: (global-set-key [right] 'forward-char) This uses the Lisp syntax for a vector containing the symbol `right'. (This binding is present in Emacs by default.) *Note Init Rebinding::, for more information about using vectors for rebinding. You can mix function keys and characters in a key sequence. This example binds `C-x ' to the command `forward-page'. (global-set-key [?\C-x next] 'forward-page) where `?\C-x' is the Lisp character constant for the character `C-x'. The vector element `next' is a symbol and therefore does not take a question mark. You can use the modifier keys , , , , and with function keys. To represent these modifiers, add the strings `C-', `M-', `H-', `s-', `A-' and `S-' at the front of the symbol name. Thus, here is how to make `Hyper-Meta-' move forward a word: (global-set-key [H-M-right] 'forward-word)  File: emacs, Node: Named ASCII Chars, Next: Non-ASCII Rebinding, Prev: Function Keys, Up: Key Bindings Named ASCII Control Characters ------------------------------ , , , , and started out as names for certain ASCII control characters, used so often that they have special keys of their own. Later, users found it convenient to distinguish in Emacs between these keys and the "same" control characters typed with the key. Emacs distinguishes these two kinds of input, when the keyboard reports these keys to Emacs. It treats the "special" keys as function keys named `tab', `return', `backspace', `linefeed', `escape', and `delete'. These function keys translate automatically into the corresponding ASCII characters _if_ they have no bindings of their own. As a result, neither users nor Lisp programs need to pay attention to the distinction unless they care to. If you do not want to distinguish between (for example) and `C-i', make just one binding, for the ASCII character (octal code 011). If you do want to distinguish, make one binding for this ASCII character, and another for the "function key" `tab'. With an ordinary ASCII terminal, there is no way to distinguish between and `C-i' (and likewise for other such pairs), because the terminal sends the same character in both cases.  File: emacs, Node: Non-ASCII Rebinding, Next: Mouse Buttons, Prev: Named ASCII Chars, Up: Key Bindings Non-ASCII Characters on the Keyboard ------------------------------------ If your keyboard has keys that send non-ASCII characters, such as accented letters, rebinding these keys is a bit tricky. There are two solutions you can use. One is to specify a keyboard coding system, using `set-keyboard-coding-system' (*note Specify Coding::). Then you can bind these keys in the usual way(1), like this: (global-set-key [?CHAR] 'some-function) Type `C-q' followed by the key you want to bind, to insert CHAR. If you don't specify the keyboard coding system, that approach won't work. Instead, you need to find out the actual code that the terminal sends. The easiest way to do this in Emacs is to create an empty buffer with `C-x b temp ', make it unibyte with `M-x toggle-enable-multibyte-characters ', then type the key to insert the character into this buffer. Move point before the character, then type `C-x ='. This displays a message in the minibuffer, showing the character code in three ways, octal, decimal and hexadecimal, all within a set of parentheses. Use the second of the three numbers, the decimal one, inside the vector to bind: (global-set-key [DECIMAL-CODE] 'some-function) If you bind 8-bit characters like this in your init file, you may find it convenient to specify that it is unibyte. *Note Enabling Multibyte::. ---------- Footnotes ---------- (1) Note that you should avoid the string syntax for binding 8-bit characters, since they will be interpreted as meta keys. *Note Strings of Events: (elisp)Strings of Events.  File: emacs, Node: Mouse Buttons, Next: Disabling, Prev: Non-ASCII Rebinding, Up: Key Bindings Rebinding Mouse Buttons ----------------------- Emacs uses Lisp symbols to designate mouse buttons, too. The ordinary mouse events in Emacs are "click" events; these happen when you press a button and release it without moving the mouse. You can also get "drag" events, when you move the mouse while holding the button down. Drag events happen when you finally let go of the button. The symbols for basic click events are `mouse-1' for the leftmost button, `mouse-2' for the next, and so on. Here is how you can redefine the second mouse button to split the current window: (global-set-key [mouse-2] 'split-window-vertically) The symbols for drag events are similar, but have the prefix `drag-' before the word `mouse'. For example, dragging the first button generates a `drag-mouse-1' event. You can also define bindings for events that occur when a mouse button is pressed down. These events start with `down-' instead of `drag-'. Such events are generated only if they have key bindings. When you get a button-down event, a corresponding click or drag event will always follow. If you wish, you can distinguish single, double, and triple clicks. A double click means clicking a mouse button twice in approximately the same place. The first click generates an ordinary click event. The second click, if it comes soon enough, generates a double-click event instead. The event type for a double-click event starts with `double-': for example, `double-mouse-3'. This means that you can give a special meaning to the second click at the same place, but it must act on the assumption that the ordinary single click definition has run when the first click was received. This constrains what you can do with double clicks, but user interface designers say that this constraint ought to be followed in any case. A double click should do something similar to the single click, only "more so." The command for the double-click event should perform the extra work for the double click. If a double-click event has no binding, it changes to the corresponding single-click event. Thus, if you don't define a particular double click specially, it executes the single-click command twice. Emacs also supports triple-click events whose names start with `triple-'. Emacs does not distinguish quadruple clicks as event types; clicks beyond the third generate additional triple-click events. However, the full number of clicks is recorded in the event list, so you can distinguish if you really want to. We don't recommend distinct meanings for more than three clicks, but sometimes it is useful for subsequent clicks to cycle through the same set of three meanings, so that four clicks are equivalent to one click, five are equivalent to two, and six are equivalent to three. Emacs also records multiple presses in drag and button-down events. For example, when you press a button twice, then move the mouse while holding the button, Emacs gets a `double-drag-' event. And at the moment when you press it down for the second time, Emacs gets a `double-down-' event (which is ignored, like all button-down events, if it has no binding). The variable `double-click-time' specifies how much time can elapse between clicks and still allow them to be grouped as a multiple click. Its value is in units of milliseconds. If the value is `nil', double clicks are not detected at all. If the value is `t', then there is no time limit. The default is 500. The variable `double-click-fuzz' specifies how much the mouse can move between clicks still allow them to be grouped as a multiple click. Its value is in units of pixels on windowed displays and in units of 1/8 of a character cell on text-mode terminals; the default is 3. The symbols for mouse events also indicate the status of the modifier keys, with the usual prefixes `C-', `M-', `H-', `s-', `A-' and `S-'. These always precede `double-' or `triple-', which always precede `drag-' or `down-'. A frame includes areas that don't show text from the buffer, such as the mode line and the scroll bar. You can tell whether a mouse button comes from a special area of the screen by means of dummy "prefix keys." For example, if you click the mouse in the mode line, you get the prefix key `mode-line' before the ordinary mouse-button symbol. Thus, here is how to define the command for clicking the first button in a mode line to run `scroll-up': (global-set-key [mode-line mouse-1] 'scroll-up) Here is the complete list of these dummy prefix keys and their meanings: `mode-line' The mouse was in the mode line of a window. `vertical-line' The mouse was in the vertical line separating side-by-side windows. (If you use scroll bars, they appear in place of these vertical lines.) `vertical-scroll-bar' The mouse was in a vertical scroll bar. (This is the only kind of scroll bar Emacs currently supports.) You can put more than one mouse button in a key sequence, but it isn't usual to do so.  File: emacs, Node: Disabling, Prev: Mouse Buttons, Up: Key Bindings Disabling Commands ------------------ Disabling a command marks the command as requiring confirmation before it can be executed. The purpose of disabling a command is to prevent beginning users from executing it by accident and being confused. An attempt to invoke a disabled command interactively in Emacs displays a window containing the command's name, its documentation, and some instructions on what to do immediately; then Emacs asks for input saying whether to execute the command as requested, enable it and execute it, or cancel. If you decide to enable the command, you are asked whether to do this permanently or just for the current session. (Enabling permanently works by automatically editing your `.emacs' file.) You can also type `!' to enable _all_ commands, for the current session only. The direct mechanism for disabling a command is to put a non-`nil' `disabled' property on the Lisp symbol for the command. Here is the Lisp program to do this: (put 'delete-region 'disabled t) If the value of the `disabled' property is a string, that string is included in the message displayed when the command is used: (put 'delete-region 'disabled "It's better to use `kill-region' instead.\n") You can make a command disabled either by editing the `.emacs' file directly or with the command `M-x disable-command', which edits the `.emacs' file for you. Likewise, `M-x enable-command' edits `.emacs' to enable a command permanently. *Note Init File::. Whether a command is disabled is independent of what key is used to invoke it; disabling also applies if the command is invoked using `M-x'. Disabling a command has no effect on calling it as a function from Lisp programs.  File: emacs, Node: Keyboard Translations, Next: Syntax, Prev: Key Bindings, Up: Customization Keyboard Translations ===================== Some keyboards do not make it convenient to send all the special characters that Emacs uses. The most common problem case is the character. Some keyboards provide no convenient way to type this very important character--usually because they were designed to expect the character `C-h' to be used for deletion. On these keyboards, if you press the key normally used for deletion, Emacs handles the `C-h' as a prefix character and offers you a list of help options, which is not what you want. You can work around this problem within Emacs by setting up keyboard translations to turn `C-h' into and into `C-h', as follows: ;; Translate `C-h' to . (keyboard-translate ?\C-h ?\C-?) ;; Translate to `C-h'. (keyboard-translate ?\C-? ?\C-h) Keyboard translations are not the same as key bindings in keymaps (*note Keymaps::). Emacs contains numerous keymaps that apply in different situations, but there is only one set of keyboard translations, and it applies to every character that Emacs reads from the terminal. Keyboard translations take place at the lowest level of input processing; the keys that are looked up in keymaps contain the characters that result from keyboard translation. On a window system, the keyboard key named is a function key and is distinct from the ASCII character named . *Note Named ASCII Chars::. Keyboard translations affect only ASCII character input, not function keys; thus, the above example used on a window system does not affect the key. However, the translation above isn't necessary on window systems, because Emacs can also distinguish between the key and `C-h'; and it normally treats as . For full information about how to use keyboard translations, see *Note Translating Input: (elisp)Translating Input.  File: emacs, Node: Syntax, Next: Init File, Prev: Keyboard Translations, Up: Customization The Syntax Table ================ All the Emacs commands which parse words or balance parentheses are controlled by the "syntax table". The syntax table says which characters are opening delimiters, which are parts of words, which are string quotes, and so on. It does this by assigning each character to one of fifteen-odd "syntax classes". In some cases it specifies some additional information also. Each major mode has its own syntax table (though related major modes sometimes share one syntax table) which it installs in each buffer that uses the mode. The syntax table installed in the current buffer is the one that all commands use, so we call it "the" syntax table. To display a description of the contents of the current syntax table, type `C-h s' (`describe-syntax'). The description of each character includes both the string you would have to give to `modify-syntax-entry' to set up that character's current syntax, starting with the character which designates its syntax class, plus some English text to explain its meaning. A syntax table is actually a Lisp object, a char-table, whose elements are cons cells. For full information on the syntax table, see *Note Syntax Tables: (elisp)Syntax Tables.  File: emacs, Node: Init File, Prev: Syntax, Up: Customization The Init File, `~/.emacs' ========================= When Emacs is started, it normally loads a Lisp program from the file `.emacs' or `.emacs.el' in your home directory. We call this file your "init file" because it specifies how to initialize Emacs for you. You can use the command line switch `-q' to prevent loading your init file, and `-u' (or `--user') to specify a different user's init file (*note Entering Emacs::). There can also be a "default init file", which is the library named `default.el', found via the standard search path for libraries. The Emacs distribution contains no such library; your site may create one for local customizations. If this library exists, it is loaded whenever you start Emacs (except when you specify `-q'). But your init file, if any, is loaded first; if it sets `inhibit-default-init' non-`nil', then `default' is not loaded. Your site may also have a "site startup file"; this is named `site-start.el', if it exists. Like `default.el', Emacs finds this file via the standard search path for Lisp libraries. Emacs loads this library before it loads your init file. To inhibit loading of this library, use the option `-no-site-file'. *Note Initial Options::. You can place `default.el' and `site-start.el' in any of the directories which Emacs searches for Lisp libraries. The variable `load-path' (*note Lisp Libraries::) specifies these directories. Many sites put these files in the `site-lisp' subdirectory of the Emacs installation directory, typically `/usr/local/share/emacs/site-lisp'. If you have a large amount of code in your `.emacs' file, you should rename it to `~/.emacs.el', and byte-compile it. *Note Byte Compilation: (elisp)Byte Compilation, for more information about compiling Emacs Lisp programs. If you are going to write actual Emacs Lisp programs that go beyond minor customization, you should read the `Emacs Lisp Reference Manual'. *Note Emacs Lisp: (elisp)Top. * Menu: * Init Syntax:: Syntax of constants in Emacs Lisp. * Init Examples:: How to do some things with an init file. * Terminal Init:: Each terminal type can have an init file. * Find Init:: How Emacs finds the init file.  File: emacs, Node: Init Syntax, Next: Init Examples, Up: Init File Init File Syntax ---------------- The `.emacs' file contains one or more Lisp function call expressions. Each of these consists of a function name followed by arguments, all surrounded by parentheses. For example, `(setq fill-column 60)' calls the function `setq' to set the variable `fill-column' (*note Filling::) to 60. The second argument to `setq' is an expression for the new value of the variable. This can be a constant, a variable, or a function call expression. In `.emacs', constants are used most of the time. They can be: Numbers: Numbers are written in decimal, with an optional initial minus sign. Strings: Lisp string syntax is the same as C string syntax with a few extra features. Use a double-quote character to begin and end a string constant. In a string, you can include newlines and special characters literally. But often it is cleaner to use backslash sequences for them: `\n' for newline, `\b' for backspace, `\r' for carriage return, `\t' for tab, `\f' for formfeed (control-L), `\e' for escape, `\\' for a backslash, `\"' for a double-quote, or `\OOO' for the character whose octal code is OOO. Backslash and double-quote are the only characters for which backslash sequences are mandatory. `\C-' can be used as a prefix for a control character, as in `\C-s' for ASCII control-S, and `\M-' can be used as a prefix for a Meta character, as in `\M-a' for `Meta-A' or `\M-\C-a' for `Control-Meta-A'. If you want to include non-ASCII characters in strings in your init file, you should consider putting a `-*-coding: CODING-SYSTEM-*-' tag on the first line which states the coding system used to save your `.emacs', as explained in *Note Recognize Coding::. This is because the defaults for decoding non-ASCII text might not yet be set up by the time Emacs reads those parts of your init file which use such strings, possibly leading Emacs to decode those strings incorrectly. Characters: Lisp character constant syntax consists of a `?' followed by either a character or an escape sequence starting with `\'. Examples: `?x', `?\n', `?\"', `?\)'. Note that strings and characters are not interchangeable in Lisp; some contexts require one and some contexts require the other. *Note Non-ASCII Rebinding::, for information about binding commands to keys which send non-ASCII characters. True: `t' stands for `true'. False: `nil' stands for `false'. Other Lisp objects: Write a single-quote (`'') followed by the Lisp object you want.  File: emacs, Node: Init Examples, Next: Terminal Init, Prev: Init Syntax, Up: Init File Init File Examples ------------------ Here are some examples of doing certain commonly desired things with Lisp expressions: * Make in C mode just insert a tab if point is in the middle of a line. (setq c-tab-always-indent nil) Here we have a variable whose value is normally `t' for `true' and the alternative is `nil' for `false'. * Make searches case sensitive by default (in all buffers that do not override this). (setq-default case-fold-search nil) This sets the default value, which is effective in all buffers that do not have local values for the variable. Setting `case-fold-search' with `setq' affects only the current buffer's local value, which is not what you probably want to do in an init file. * Specify your own email address, if Emacs can't figure it out correctly. (setq user-mail-address "coon@yoyodyne.com") Various Emacs packages that need your own email address use the value of `user-mail-address'. * Make Text mode the default mode for new buffers. (setq default-major-mode 'text-mode) Note that `text-mode' is used because it is the command for entering Text mode. The single-quote before it makes the symbol a constant; otherwise, `text-mode' would be treated as a variable name. * Set up defaults for the Latin-1 character set which supports most of the languages of Western Europe. (set-language-environment "Latin-1") * Turn on Auto Fill mode automatically in Text mode and related modes. (add-hook 'text-mode-hook '(lambda () (auto-fill-mode 1))) This shows how to add a hook function to a normal hook variable (*note Hooks::). The function we supply is a list starting with `lambda', with a single-quote in front of it to make it a list constant rather than an expression. It's beyond the scope of this manual to explain Lisp functions, but for this example it is enough to know that the effect is to execute `(auto-fill-mode 1)' when Text mode is entered. You can replace that with any other expression that you like, or with several expressions in a row. Emacs comes with a function named `turn-on-auto-fill' whose definition is `(lambda () (auto-fill-mode 1))'. Thus, a simpler way to write the above example is as follows: (add-hook 'text-mode-hook 'turn-on-auto-fill) * Load the installed Lisp library named `foo' (actually a file `foo.elc' or `foo.el' in a standard Emacs directory). (load "foo") When the argument to `load' is a relative file name, not starting with `/' or `~', `load' searches the directories in `load-path' (*note Lisp Libraries::). * Load the compiled Lisp file `foo.elc' from your home directory. (load "~/foo.elc") Here an absolute file name is used, so no searching is done. * Tell Emacs to find the definition for the function `myfunction' by loading a Lisp library named `mypackage' (i.e. a file `mypackage.elc' or `mypackage.el'): (autoload 'myfunction "mypackage" "Do what I say." t) Here the string `"Do what I say."' is the function's documentation string. You specify it in the `autoload' definition so it will be available for help commands even when the package is not loaded. The last argument, `t', indicates that this function is interactive; that is, it can be invoked interactively by typing `M-x myfunction ' or by binding it to a key. If the function is not interactive, omit the `t' or use `nil'. * Rebind the key `C-x l' to run the function `make-symbolic-link'. (global-set-key "\C-xl" 'make-symbolic-link) or (define-key global-map "\C-xl" 'make-symbolic-link) Note once again the single-quote used to refer to the symbol `make-symbolic-link' instead of its value as a variable. * Do the same thing for Lisp mode only. (define-key lisp-mode-map "\C-xl" 'make-symbolic-link) * Redefine all keys which now run `next-line' in Fundamental mode so that they run `forward-line' instead. (substitute-key-definition 'next-line 'forward-line global-map) * Make `C-x C-v' undefined. (global-unset-key "\C-x\C-v") One reason to undefine a key is so that you can make it a prefix. Simply defining `C-x C-v ANYTHING' will make `C-x C-v' a prefix, but `C-x C-v' must first be freed of its usual non-prefix definition. * Make `$' have the syntax of punctuation in Text mode. Note the use of a character constant for `$'. (modify-syntax-entry ?\$ "." text-mode-syntax-table) * Enable the use of the command `narrow-to-region' without confirmation. (put 'narrow-to-region 'disabled nil)  File: emacs, Node: Terminal Init, Next: Find Init, Prev: Init Examples, Up: Init File Terminal-specific Initialization -------------------------------- Each terminal type can have a Lisp library to be loaded into Emacs when it is run on that type of terminal. For a terminal type named TERMTYPE, the library is called `term/TERMTYPE' and it is found by searching the directories `load-path' as usual and trying the suffixes `.elc' and `.el'. Normally it appears in the subdirectory `term' of the directory where most Emacs libraries are kept. The usual purpose of the terminal-specific library is to map the escape sequences used by the terminal's function keys onto more meaningful names, using `function-key-map'. See the file `term/lk201.el' for an example of how this is done. Many function keys are mapped automatically according to the information in the Termcap data base; the terminal-specific library needs to map only the function keys that Termcap does not specify. When the terminal type contains a hyphen, only the part of the name before the first hyphen is significant in choosing the library name. Thus, terminal types `aaa-48' and `aaa-30-rv' both use the library `term/aaa'. The code in the library can use `(getenv "TERM")' to find the full terminal type name. The library's name is constructed by concatenating the value of the variable `term-file-prefix' and the terminal type. Your `.emacs' file can prevent the loading of the terminal-specific library by setting `term-file-prefix' to `nil'. Emacs runs the hook `term-setup-hook' at the end of initialization, after both your `.emacs' file and any terminal-specific library have been read in. Add hook functions to this hook if you wish to override part of any of the terminal-specific libraries and to define initializations for terminals that do not have a library. *Note Hooks::.  File: emacs, Node: Find Init, Prev: Terminal Init, Up: Init File How Emacs Finds Your Init File ------------------------------ Normally Emacs uses the environment variable `HOME' to find `.emacs'; that's what `~' means in a file name. But if you run Emacs from a shell started by `su', Emacs tries to find your own `.emacs', not that of the user you are currently pretending to be. The idea is that you should get your own editor customizations even if you are running as the super user. More precisely, Emacs first determines which user's init file to use. It gets the user name from the environment variables `LOGNAME' and `USER'; if neither of those exists, it uses effective user-ID. If that user name matches the real user-ID, then Emacs uses `HOME'; otherwise, it looks up the home directory corresponding to that user name in the system's data base of users.  File: emacs, Node: Quitting, Next: Lossage, Prev: Customization, Up: Top Quitting and Aborting ===================== `C-g' `C- (MS-DOS only)' Quit: cancel running or partially typed command. `C-]' Abort innermost recursive editing level and cancel the command which invoked it (`abort-recursive-edit'). ` ' Either quit or abort, whichever makes sense (`keyboard-escape-quit'). `M-x top-level' Abort all recursive editing levels that are currently executing. `C-x u' Cancel a previously made change in the buffer contents (`undo'). There are two ways of canceling commands which are not finished executing: "quitting" with `C-g', and "aborting" with `C-]' or `M-x top-level'. Quitting cancels a partially typed command or one which is already running. Aborting exits a recursive editing level and cancels the command that invoked the recursive edit. (*Note Recursive Edit::.) Quitting with `C-g' is used for getting rid of a partially typed command, or a numeric argument that you don't want. It also stops a running command in the middle in a relatively safe way, so you can use it if you accidentally give a command which takes a long time. In particular, it is safe to quit out of killing; either your text will _all_ still be in the buffer, or it will _all_ be in the kill ring (or maybe both). Quitting an incremental search does special things documented under searching; in general, it may take two successive `C-g' characters to get out of a search (*note Incremental Search::). On MS-DOS, the character `C-' serves as a quit character like `C-g'. The reason is that it is not feasible, on MS-DOS, to recognize `C-g' while a command is running, between interactions with the user. By contrast, it _is_ feasible to recognize `C-' at all times. *Note MS-DOS Input::. `C-g' works by setting the variable `quit-flag' to `t' the instant `C-g' is typed; Emacs Lisp checks this variable frequently and quits if it is non-`nil'. `C-g' is only actually executed as a command if you type it while Emacs is waiting for input. In that case, the command it runs is `keyboard-quit'. If you quit with `C-g' a second time before the first `C-g' is recognized, you activate the "emergency escape" feature and return to the shell. *Note Emergency Escape::. There may be times when you cannot quit. When Emacs is waiting for the operating system to do something, quitting is impossible unless special pains are taken for the particular system call within Emacs where the waiting occurs. We have done this for the system calls that users are likely to want to quit from, but it's possible you will find another. In one very common case--waiting for file input or output using NFS--Emacs itself knows how to quit, but many NFS implementations simply do not allow user programs to stop waiting for NFS when the NFS server is hung. Aborting with `C-]' (`abort-recursive-edit') is used to get out of a recursive editing level and cancel the command which invoked it. Quitting with `C-g' does not do this, and could not do this, because it is used to cancel a partially typed command _within_ the recursive editing level. Both operations are useful. For example, if you are in a recursive edit and type `C-u 8' to enter a numeric argument, you can cancel that argument with `C-g' and remain in the recursive edit. The command ` ' (`keyboard-escape-quit') can either quit or abort. This key was defined because is used to "get out" in many PC programs. It can cancel a prefix argument, clear a selected region, or get out of a Query Replace, like `C-g'. It can get out of the minibuffer or a recursive edit, like `C-]'. It can also get out of splitting the frame into multiple windows, like `C-x 1'. One thing it cannot do, however, is stop a command that is running. That's because it executes as an ordinary command, and Emacs doesn't notice it until it is ready for a command. The command `M-x top-level' is equivalent to "enough" `C-]' commands to get you out of all the levels of recursive edits that you are in. `C-]' gets you out one level at a time, but `M-x top-level' goes out all levels at once. Both `C-]' and `M-x top-level' are like all other commands, and unlike `C-g', in that they take effect only when Emacs is ready for a command. `C-]' is an ordinary key and has its meaning only because of its binding in the keymap. *Note Recursive Edit::. `C-x u' (`undo') is not strictly speaking a way of canceling a command, but you can think of it as canceling a command that already finished executing. *Note Undo::, for more information about the undo facility.  File: emacs, Node: Lossage, Next: Bugs, Prev: Quitting, Up: Top Dealing with Emacs Trouble ========================== This section describes various conditions in which Emacs fails to work normally, and how to recognize them and correct them. For a list of additional problems you might encounter, see *Note Bugs and problems: (efaq)Bugs and problems, and the file `etc/PROBLEMS' in the Emacs distribution. Type `C-h F' to read the FAQ; type `C-h P' to read the `PROBLEMS' file. * Menu: * DEL Does Not Delete:: What to do if doesn't delete. * Stuck Recursive:: `[...]' in mode line around the parentheses. * Screen Garbled:: Garbage on the screen. * Text Garbled:: Garbage in the text. * Unasked-for Search:: Spontaneous entry to incremental search. * Memory Full:: How to cope when you run out of memory. * After a Crash:: Recovering editing in an Emacs session that crashed. * Emergency Escape:: Emergency escape--- What to do if Emacs stops responding. * Total Frustration:: When you are at your wits' end.  File: emacs, Node: DEL Does Not Delete, Next: Stuck Recursive, Up: Lossage If Fails to Delete ------------------------ Every keyboard has a large key, a little ways above the or key, which you normally use outside Emacs to erase the last character that you typed. We call this key "the usual erasure key". In Emacs, it is supposed to be equivalent to , and when Emacs is properly configured for your terminal, it translates that key into the character . When Emacs starts up using a window system, it determines automatically which key should be . In some unusual cases Emacs gets the wrong information from the system. If the usual erasure key deletes forwards instead of backwards, that is probably what happened--Emacs ought to be treating the key as , but it isn't. With a window system, if the usual erasure key is labeled and there is a key elsewhere, but the key deletes backward instead of forward, that too suggests Emacs got the wrong information--but in the opposite sense. It ought to be treating the key as , and treating differently, but it isn't. On a text-only terminal, if you find the usual erasure key prompts for a Help command, like `Control-h', instead of deleting a character, it means that key is actually sending the character. Emacs ought to be treating as , but it isn't. In all of those cases, the immediate remedy is the same: use the command `M-x normal-erase-is-backspace-mode'. This toggles between the two modes that Emacs supports for handling , so if Emacs starts in the wrong mode, it should switch to the right mode. On a text-only terminal, if you want to ask for help when is treated as , use ; `C-?' may also work, if it sends character code 127. To fix the problem automatically for every Emacs session, you can put one of the following lines into your `.emacs' file (*note Init File::). For the first case above, where deletes forwards instead of backwards, use this line to make act as (resulting in behavior compatible with Emacs 20 and previous versions): (normal-erase-is-backspace-mode 0) For the other two cases, where ought to act as , use this line: (normal-erase-is-backspace-mode 1) Another way to fix the problem for every Emacs session is to customize the variable `normal-erase-is-backspace': the value `t' specifies the mode where or is , and `nil' specifies the other mode. *Note Easy Customization::. With a window system, it can also happen that the usual erasure key is labeled , there is a key elsewhere, and both keys delete forward. This probably means that someone has redefined your key as a key. With X, this is typically done with a command to the `xmodmap' program when you start the server or log in. The most likely motive for this customization was to support old versions of Emacs, so we recommend you simply remove it now.  File: emacs, Node: Stuck Recursive, Next: Screen Garbled, Prev: DEL Does Not Delete, Up: Lossage Recursive Editing Levels ------------------------ Recursive editing levels are important and useful features of Emacs, but they can seem like malfunctions to the user who does not understand them. If the mode line has square brackets `[...]' around the parentheses that contain the names of the major and minor modes, you have entered a recursive editing level. If you did not do this on purpose, or if you don't understand what that means, you should just get out of the recursive editing level. To do so, type `M-x top-level'. This is called getting back to top level. *Note Recursive Edit::.  File: emacs, Node: Screen Garbled, Next: Text Garbled, Prev: Stuck Recursive, Up: Lossage Garbage on the Screen --------------------- If the data on the screen looks wrong, the first thing to do is see whether the text is really wrong. Type `C-l' to redisplay the entire screen. If the screen appears correct after this, the problem was entirely in the previous screen update. (Otherwise, see the following section.) Display updating problems often result from an incorrect termcap entry for the terminal you are using. The file `etc/TERMS' in the Emacs distribution gives the fixes for known problems of this sort. `INSTALL' contains general advice for these problems in one of its sections. Very likely there is simply insufficient padding for certain display operations. To investigate the possibility that you have this sort of problem, try Emacs on another terminal made by a different manufacturer. If problems happen frequently on one kind of terminal but not another kind, it is likely to be a bad termcap entry, though it could also be due to a bug in Emacs that appears for terminals that have or that lack specific features.  File: emacs, Node: Text Garbled, Next: Unasked-for Search, Prev: Screen Garbled, Up: Lossage Garbage in the Text ------------------- If `C-l' shows that the text is wrong, try undoing the changes to it using `C-x u' until it gets back to a state you consider correct. Also try `C-h l' to find out what command you typed to produce the observed results. If a large portion of text appears to be missing at the beginning or end of the buffer, check for the word `Narrow' in the mode line. If it appears, the text you don't see is probably still present, but temporarily off-limits. To make it accessible again, type `C-x n w'. *Note Narrowing::.  File: emacs, Node: Unasked-for Search, Next: Memory Full, Prev: Text Garbled, Up: Lossage Spontaneous Entry to Incremental Search --------------------------------------- If Emacs spontaneously displays `I-search:' at the bottom of the screen, it means that the terminal is sending `C-s' and `C-q' according to the poorly designed xon/xoff "flow control" protocol. If this happens to you, your best recourse is to put the terminal in a mode where it will not use flow control, or give it so much padding that it will never send a `C-s'. (One way to increase the amount of padding is to set the variable `baud-rate' to a larger value. Its value is the terminal output speed, measured in the conventional units of baud.) If you don't succeed in turning off flow control, the next best thing is to tell Emacs to cope with it. To do this, call the function `enable-flow-control'. Typically there are particular terminal types with which you must use flow control. You can conveniently ask for flow control on those terminal types only, using `enable-flow-control-on'. For example, if you find you must use flow control on VT-100 and H19 terminals, put the following in your `.emacs' file: (enable-flow-control-on "vt100" "h19") When flow control is enabled, you must type `C-\' to get the effect of a `C-s', and type `C-^' to get the effect of a `C-q'. (These aliases work by means of keyboard translations; see *Note Keyboard Translations::.)  File: emacs, Node: Memory Full, Next: After a Crash, Prev: Unasked-for Search, Up: Lossage Running out of Memory --------------------- If you get the error message `Virtual memory exceeded', save your modified buffers with `C-x s'. This method of saving them has the smallest need for additional memory. Emacs keeps a reserve of memory which it makes available when this error happens; that should be enough to enable `C-x s' to complete its work. Once you have saved your modified buffers, you can exit this Emacs job and start another, or you can use `M-x kill-some-buffers' to free space in the current Emacs job. If you kill buffers containing a substantial amount of text, you can safely go on editing. Emacs refills its memory reserve automatically when it sees sufficient free space available, in case you run out of memory another time. Do not use `M-x buffer-menu' to save or kill buffers when you run out of memory, because the buffer menu needs a fair amount of memory itself, and the reserve supply may not be enough.