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This is Info file ../../info/xemacs.info, produced by Makeinfo-1.63 from the input file xemacs.texi. This file documents the XEmacs editor. Copyright (C) 1985, 1986, 1988 Richard M. Stallman. Copyright (C) 1991, 1992, 1993, 1994 Lucid, Inc. Copyright (C) 1993, 1994 Sun Microsystems, Inc. Copyright (C) 1995 Amdahl Corporation. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided also that the sections entitled "The GNU Manifesto", "Distribution" and "GNU General Public License" are included exactly as in the original, and provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions, except that the sections entitled "The GNU Manifesto", "Distribution" and "GNU General Public License" may be included in a translation approved by the author instead of in the original English. File: xemacs.info, Node: Shell Mode, Next: Terminal emulator, Prev: Interactive Shell, Up: Shell Shell Mode ---------- The shell buffer uses Shell mode, which defines several special keys attached to the `C-c' prefix. They are chosen to resemble the usual editing and job control characters present in shells that are not under XEmacs, except that you must type `C-c' first. Here is a list of the special key bindings of Shell mode: `RET' At end of buffer send line as input; otherwise, copy current line to end of buffer and send it (`send-shell-input'). When a line is copied, any text at the beginning of the line that matches the variable `shell-prompt-pattern' is left out; this variable's value should be a regexp string that matches the prompts that you use in your subshell. `C-c C-d' Send end-of-file as input, probably causing the shell or its current subjob to finish (`shell-send-eof'). `C-d' If point is not at the end of the buffer, delete the next character just like most other modes. If point is at the end of the buffer, send end-of-file as input, instead of generating an error as in other modes (`comint-delchar-or-maybe-eof'). `C-c C-u' Kill all text that has yet to be sent as input (`kill-shell-input'). `C-c C-w' Kill a word before point (`backward-kill-word'). `C-c C-c' Interrupt the shell or its current subjob if any (`interrupt-shell-subjob'). `C-c C-z' Stop the shell or its current subjob if any (`stop-shell-subjob'). `C-c C-\' Send quit signal to the shell or its current subjob if any (`quit-shell-subjob'). `C-c C-o' Delete last batch of output from shell (`kill-output-from-shell'). `C-c C-r' Scroll top of last batch of output to top of window (`show-output-from-shell'). `C-c C-y' Copy the previous bunch of shell input and insert it into the buffer before point (`copy-last-shell-input'). No final newline is inserted, and the input copied is not resubmitted until you type RET. `M-p' Move backward through the input history. Search for a matching command if you have typed the beginning of a command (`comint-previous-input'). `M-n' Move forward through the input history. Useful when you are using M-p quickly and go past the desired command (`comint-next-input'). `TAB' Complete the file name preceding point (`comint-dynamic-complete'). File: xemacs.info, Node: Terminal emulator, Next: Term Mode, Prev: Shell Mode, Up: Shell Interactive Inferior Shell with Terminal Emulator ------------------------------------------------- To run a subshell in a terminal emulator, putting its typescript in an XEmacs buffer, use `M-x term'. This creates (or reuses) a buffer named `*term*' and runs a subshell with input coming from your keyboard and output going to that buffer. All the normal keys that you type are sent without any interpretation by XEmacs directly to the subshell, as "terminal input." Any "echo" of your input is the responsibility of the subshell. (The exception is the terminal escape character, which by default is `C-c'. *note Term Mode::..) Any "terminal output" from the subshell goes into the buffer, advancing point. Some programs (such as XEmacs itself) need to control the appearance on the terminal screen in detail. They do this by sending special control codes. The exact control codes needed vary from terminal to terminal, but nowadays most terminals and terminal emulators (including xterm) understand the so-called "ANSI escape sequences" (first popularized by the Digital's VT100 family of terminal). The term mode also understands these escape sequences, and for each control code does the appropriate thing to change the buffer so that the appearance of the window will match what it would be on a real terminal. Thus you can actually run XEmacs inside an XEmacs Term window! XEmacs does not wait for the subshell to do anything. You can switch windows or buffers and edit them while the shell is waiting, or while it is running a command. Output from the subshell waits until XEmacs has time to process it; this happens whenever XEmacs is waiting for keyboard input or for time to elapse. To make multiple terminal emulators, rename the buffer `*term*' to something different using `M-x rename-uniquely', just as with Shell mode. The file name used to load the subshell is determined the same way as for Shell mode. Unlike Shell mode, Term mode does not track the current directory by examining your input. Instead, if you use a programmable shell, you can have it tell Term what the current directory is. This is done automatically by bash for version 1.15 and later. File: xemacs.info, Node: Term Mode, Next: Paging in Term, Prev: Terminal emulator, Up: Shell Term Mode --------- Term uses Term mode, which has two input modes: In line mode, Term basically acts like Shell mode. *Note Shell Mode::. In Char mode, each character is sent directly to the inferior subshell, except for the Term escape character, normally `C-c'. To switch between line and char mode, use these commands: findex term-char-mode `C-c C-k' Switch to line mode. Do nothing if already in line mode. `C-c C-j' Switch to char mode. Do nothing if already in char mode. The following commands are only available in Char mode: `C-c C-c' Send a literal C-c to the sub-shell. `C-c C-x' A prefix command to conveniently access the global C-x commands. For example, `C-c C-x o' invokes the global binding of `C-x o', which is normally `other-window'. File: xemacs.info, Node: Paging in Term, Prev: Term Mode, Up: Shell Paging in the terminal emulator ------------------------------- Term mode has a pager feature. When the pager is enabled, term mode will pause at the end of each screenful. `C-c C-q' Toggles the pager feature: Disables the pager if it is enabled, and vice versa. This works in both line and char modes. If the pager enabled, the mode-line contains the word `page'. If the pager is enabled, and Term receives more than a screenful of output since your last input, Term will enter More break mode. This is indicated by `**MORE**' in the mode-line. Type a `Space' to display the next screenful of output. Type `?' to see your other options. The interface is similar to the Unix `more' program. File: xemacs.info, Node: Narrowing, Next: Hardcopy, Prev: Shell, Up: Top Narrowing ========= "Narrowing" means focusing in on some portion of the buffer, making the rest temporarily invisible and inaccessible. Cancelling the narrowing and making the entire buffer once again visible is called "widening". The amount of narrowing in effect in a buffer at any time is called the buffer's "restriction". `C-x n n' Narrow down to between point and mark (`narrow-to-region'). `C-x n w' Widen to make the entire buffer visible again (`widen'). Narrowing sometimes makes it easier to concentrate on a single subroutine or paragraph by eliminating clutter. It can also be used to restrict the range of operation of a replace command or repeating keyboard macro. The word `Narrow' appears in the mode line whenever narrowing is in effect. When you have narrowed to a part of the buffer, that part appears to be all there is. You can't see the rest, can't move into it (motion commands won't go outside the visible part), and can't change it in any way. However, the invisible text is not gone; if you save the file, it will be saved. The primary narrowing command is `C-x n n' (`narrow-to-region'). It sets the current buffer's restrictions so that the text in the current region remains visible but all text before the region or after the region is invisible. Point and mark do not change. Because narrowing can easily confuse users who do not understand it, `narrow-to-region' is normally a disabled command. Attempting to use this command asks for confirmation and gives you the option of enabling it; once you enable the command, confirmation will no longer be required. *Note Disabling::. To undo narrowing, use `C-x n w' (`widen'). This makes all text in the buffer accessible again. Use the `C-x =' command to get information on what part of the buffer you narrowed down. *Note Position Info::. File: xemacs.info, Node: Hardcopy, Next: Recursive Edit, Prev: Narrowing, Up: Top Hardcopy Output =============== The XEmacs commands for making hardcopy derive their names from the Unix commands `print' and `lpr'. `M-x print-buffer' Print hardcopy of current buffer using Unix command `print' (`lpr -p'). This command adds page headings containing the file name and page number. `M-x lpr-buffer' Print hardcopy of current buffer using Unix command `lpr'. This command does not add page headings. `M-x print-region' Like `print-buffer', but prints only the current region. `M-x lpr-region' Like `lpr-buffer', but prints only the current region. All the hardcopy commands pass extra switches to the `lpr' program based on the value of the variable `lpr-switches'. Its value should be a list of strings, each string a switch starting with `-'. For example, the value could be `("-Pfoo")' to print on printer `foo'. File: xemacs.info, Node: Recursive Edit, Next: Dissociated Press, Prev: Hardcopy, Up: Top Recursive Editing Levels ======================== A "recursive edit" is a situation in which you are using XEmacs commands to perform arbitrary editing while in the middle of another XEmacs command. For example, when you type `C-r' inside a `query-replace', you enter a recursive edit in which you can change the current buffer. When you exit from the recursive edit, you go back to the `query-replace'. "Exiting" a recursive edit means returning to the unfinished command, which continues execution. For example, exiting the recursive edit requested by `C-r' in `query-replace' causes query replacing to resume. Exiting is done with `C-M-c' (`exit-recursive-edit'). You can also "abort" a recursive edit. This is like exiting, but also quits the unfinished command immediately. Use the command `C-]' (`abort-recursive-edit') for this. *Note Quitting::. The mode line shows you when you are in a recursive edit by displaying square brackets around the parentheses that always surround the major and minor mode names. Every window's mode line shows the square brackets, since XEmacs as a whole, rather than any particular buffer, is in a recursive edit. It is possible to be in recursive edits within recursive edits. For example, after typing `C-r' in a `query-replace', you might type a command that entered the debugger. In such a case, two or more sets of square brackets appear in the mode line(s). Exiting the inner recursive edit (here with the debugger `c' command) resumes the query-replace command where it called the debugger. After the end of the query-replace command, you would be able to exit the first recursive edit. Aborting exits only one level of recursive edit; it returns to the command level of the previous recursive edit. You can then abort that one as well. The command `M-x top-level' aborts all levels of recursive edits, returning immediately to the top level command reader. The text you edit inside the recursive edit need not be the same text that you were editing at top level. If the command that invokes the recursive edit selects a different buffer first, that is the buffer you will edit recursively. You can switch buffers within the recursive edit in the normal manner (as long as the buffer-switching keys have not been rebound). While you could theoretically do the rest of your editing inside the recursive edit, including visiting files, this could have surprising effects (such as stack overflow) from time to time. It is best if you always exit or abort a recursive edit when you no longer need it. In general, XEmacs tries to avoid using recursive edits. It is usually preferable to allow users to switch among the possible editing modes in any order they like. With recursive edits, the only way to get to another state is to go "back" to the state that the recursive edit was invoked from. File: xemacs.info, Node: Dissociated Press, Next: CONX, Prev: Recursive Edit, Up: Top Dissociated Press ================= `M-x dissociated-press' is a command for scrambling a file of text either word by word or character by character. Starting from a buffer of straight English, it produces extremely amusing output. The input comes from the current XEmacs buffer. Dissociated Press writes its output in a buffer named `*Dissociation*', and redisplays that buffer after every couple of lines (approximately) to facilitate reading it. `dissociated-press' asks every so often whether to continue operating. Answer `n' to stop it. You can also stop at any time by typing `C-g'. The dissociation output remains in the `*Dissociation*' buffer for you to copy elsewhere if you wish. Dissociated Press operates by jumping at random from one point in the buffer to another. In order to produce plausible output rather than gibberish, it insists on a certain amount of overlap between the end of one run of consecutive words or characters and the start of the next. That is, if it has just printed out `president' and then decides to jump to a different point in the file, it might spot the `ent' in `pentagon' and continue from there, producing `presidentagon'. Long sample texts produce the best results. A positive argument to `M-x dissociated-press' tells it to operate character by character, and specifies the number of overlap characters. A negative argument tells it to operate word by word and specifies the number of overlap words. In this mode, whole words are treated as the elements to be permuted, rather than characters. No argument is equivalent to an argument of two. For your againformation, the output goes only into the buffer `*Dissociation*'. The buffer you start with is not changed. Dissociated Press produces nearly the same results as a Markov chain based on a frequency table constructed from the sample text. It is, however, an independent, ignoriginal invention. Dissociated Press techniquitously copies several consecutive characters from the sample between random choices, whereas a Markov chain would choose randomly for each word or character. This makes for more plausible sounding results and runs faster. It is a mustatement that too much use of Dissociated Press can be a developediment to your real work. Sometimes to the point of outragedy. And keep dissociwords out of your documentation, if you want it to be well userenced and properbose. Have fun. Your buggestions are welcome. File: xemacs.info, Node: CONX, Next: Amusements, Prev: Dissociated Press, Up: Top CONX ==== Besides producing a file of scrambled text with Dissociated Press, you can generate random sentences by using CONX. `M-x conx' Generate random sentences in the `*conx*' buffer. `M-x conx-buffer' Absorb the text in the current buffer into the `conx' database. `M-x conx-init' Forget the current word-frequency tree. `M-x conx-load' Load a `conx' database that has been previously saved with `M-x conx-save'. `M-x conx-region' Absorb the text in the current buffer into the `conx' database. `M-x conx-save' Save the current `conx' database to a file for future retrieval. Copy text from a buffer using `M-x conx-buffer' or `M-x conx-region' and then type `M-x conx'. Output is continuously generated until you type ^G. You can save the `conx' database to a file with `M-x conx-save', which you can retrieve with `M-x conx-load'. To clear the database, use `M-x conx-init'. File: xemacs.info, Node: Amusements, Next: Emulation, Prev: CONX, Up: Top Other Amusements ================ If you are a little bit bored, you can try `M-x hanoi'. If you are considerably bored, give it a numeric argument. If you are very, very bored, try an argument of 9. Sit back and watch. When you are frustrated, try the famous Eliza program. Just do `M-x doctor'. End each input by typing `RET' twice. When you are feeling strange, type `M-x yow'. File: xemacs.info, Node: Emulation, Next: Customization, Prev: Amusements, Up: Top Emulation ========= XEmacs can be programmed to emulate (more or less) most other editors. Standard facilities can emulate these: Viper (a vi emulator) In XEmacs, Viper is the preferred emulation of vi within XEmacs. Viper is designed to allow you to take advantage of the best features of XEmacs while still doing your basic editing in a familiar, vi-like fashion. Viper provides various different levels of vi emulation, from a quite complete emulation that allows almost no access to native XEmacs commands, to an "expert" mode that combines the most useful vi commands with the most useful XEmacs commands. To start Viper, put the command (require 'viper) in your `.emacs' file. Viper comes with a separate manual that is provided standard with the XEmacs distribution. evi (alternative vi emulator) evi is an alternative vi emulator that also provides a nearly complete emulation of vi. evi comes with a separate manual that is provided standard with the XEmacs distribution. Warning: loading more than one vi emulator at once may cause name conflicts; no one has checked. EDT (DEC VMS editor) Turn on EDT emulation with `M-x edt-emulation-on'. `M-x edt-emulation-off' restores normal Emacs command bindings. Most of the EDT emulation commands are keypad keys, and most standard Emacs key bindings are still available. The EDT emulation rebindings are done in the global keymap, so there is no problem switching buffers or major modes while in EDT emulation. Gosling Emacs Turn on emulation of Gosling Emacs (aka Unipress Emacs) with `M-x set-gosmacs-bindings'. This redefines many keys, mostly on the `C-x' and `ESC' prefixes, to work as they do in Gosmacs. `M-x set-gnu-bindings' returns to normal XEmacs by rebinding the same keys to the definitions they had at the time `M-x set-gosmacs-bindings' was done. It is also possible to run Mocklisp code written for Gosling Emacs. *Note Mocklisp::. File: xemacs.info, Node: Customization, Next: Quitting, Prev: Emulation, Up: Top Customization ************* This chapter talks about various topics relevant to adapting the behavior of Emacs in minor ways. All kinds of customization affect only the particular Emacs job that you do them in. They are completely lost when you kill the Emacs job, and have no effect on other Emacs jobs you may run at the same time or later. The only way an Emacs job can affect anything outside of it is by writing a file; in particular, the only way to make a customization `permanent' is to put something in your `.emacs' file or other appropriate file to do the customization in each session. *Note Init File::. * Menu: * Minor Modes:: Each minor mode is one feature you can turn on independently of any others. * Variables:: Many Emacs commands examine Emacs variables to decide what to do; by setting variables, you can control their functioning. * Keyboard Macros:: A keyboard macro records a sequence of keystrokes to be replayed with a single command. * Key Bindings:: The keymaps say what command each key runs. By changing them, you can "redefine keys". * Syntax:: The syntax table controls how words and expressions are parsed. * Init File:: How to write common customizations in the `.emacs' file. * Audible Bell:: Changing how Emacs sounds the bell. * Faces:: Changing the fonts and colors of a region of text. * X Resources:: X resources controlling various aspects of the behavior of XEmacs. File: xemacs.info, Node: Minor Modes, Next: Variables, Up: Customization Minor Modes =========== Minor modes are options which you can use or not. For example, Auto Fill mode is a minor mode in which SPC breaks lines between words as you type. All the minor modes are independent of each other and of the selected major mode. Most minor modes inform you in the mode line when they are on; for example, `Fill' in the mode line means that Auto Fill mode is on. Append `-mode' to the name of a minor mode to get the name of a command function that turns the mode on or off. Thus, the command to enable or disable Auto Fill mode is called `M-x auto-fill-mode'. These commands are usually invoked with `M-x', but you can bind keys to them if you wish. With no argument, the function turns the mode on if it was off and off if it was on. This is known as "toggling". A positive argument always turns the mode on, and an explicit zero argument or a negative argument always turns it off. Auto Fill mode allows you to enter filled text without breaking lines explicitly. Emacs inserts newlines as necessary to prevent lines from becoming too long. *Note Filling::. Overwrite mode causes ordinary printing characters to replace existing text instead of moving it to the right. For example, if point is in front of the `B' in `FOOBAR', and you type a `G' in Overwrite mode, it changes to `FOOGAR', instead of `FOOGBAR'. Abbrev mode allows you to define abbreviations that automatically expand as you type them. For example, `amd' might expand to `abbrev mode'. *Note Abbrevs::, for full information. File: xemacs.info, Node: Variables, Next: Keyboard Macros, Prev: Minor Modes, Up: Customization Variables ========= A "variable" is a Lisp symbol which has a value. Variable names can contain any characters, but by convention they are words separated by hyphens. A variable can also have a documentation string, which describes what kind of value it should have and how the value will be used. Lisp allows any variable to have any kind of value, but most variables that Emacs uses require a value of a certain type. Often the value has to be a string or a number. Sometimes we say that a certain feature is turned on if a variable is "non-`nil'," meaning that if the variable's value is `nil', the feature is off, but the feature is on for any other value. The conventional value to turn on the feature--since you have to pick one particular value when you set the variable--is `t'. Emacs uses many Lisp variables for internal recordkeeping, as any Lisp program must, but the most interesting variables for you are the ones that exist for the sake of customization. Emacs does not (usually) change the values of these variables; instead, you set the values, and thereby alter and control the behavior of certain Emacs commands. These variables are called "options". Most options are documented in this manual and appear in the Variable Index (*note Variable Index::.). One example of a variable which is an option is `fill-column', which specifies the position of the right margin (as a number of characters from the left margin) to be used by the fill commands (*note Filling::.). * Menu: * Examining:: Examining or setting one variable's value. * Edit Options:: Examining or editing list of all variables' values. * Locals:: Per-buffer values of variables. * File Variables:: How files can specify variable values. File: xemacs.info, Node: Examining, Next: Edit Options, Up: Variables Examining and Setting Variables ------------------------------- `C-h v' `M-x describe-variable' Print the value and documentation of a variable. `M-x set-variable' Change the value of a variable. To examine the value of a single variable, use `C-h v' (`describe-variable'), which reads a variable name using the minibuffer, with completion. It prints both the value and the documentation of the variable. C-h v fill-column RET prints something like: fill-column's value is 75 Documentation: *Column beyond which automatic line-wrapping should happen. Automatically becomes local when set in any fashion. The star at the beginning of the documentation indicates that this variable is an option. `C-h v' is not restricted to options; it allows any variable name. If you know which option you want to set, you can use `M-x set-variable' to set it. This prompts for the variable name in the minibuffer (with completion), and then prompts for a Lisp expression for the new value using the minibuffer a second time. For example, M-x set-variable RET fill-column RET 75 RET sets `fill-column' to 75, as if you had executed the Lisp expression `(setq fill-column 75)'. Setting variables in this way, like all means of customizing Emacs except where explicitly stated, affects only the current Emacs session. File: xemacs.info, Node: Edit Options, Next: Locals, Prev: Examining, Up: Variables Editing Variable Values ----------------------- `M-x list-options' Display a buffer listing names, values, and documentation of all options. `M-x edit-options' Change option values by editing a list of options. `M-x list-options' displays a list of all Emacs option variables in an Emacs buffer named `*List Options*'. Each option is shown with its documentation and its current value. Here is what a portion of it might look like: ;; exec-path: ("." "/usr/local/bin" "/usr/ucb" "/bin" "/usr/bin" "/u2/emacs/etc") *List of directories to search programs to run in subprocesses. Each element is a string (directory name) or nil (try the default directory). ;; ;; fill-column: 75 *Column beyond which automatic line-wrapping should happen. Automatically becomes local when set in any fashion. ;; `M-x edit-options' goes one step further and immediately selects the `*List Options*' buffer; this buffer uses the major mode Options mode, which provides commands that allow you to point at an option and change its value: `s' Set the variable point is in or near to a new value read using the minibuffer. `x' Toggle the variable point is in or near: if the value was `nil', it becomes `t'; otherwise it becomes `nil'. `1' Set the variable point is in or near to `t'. `0' Set the variable point is in or near to `nil'. `n' `p' Move to the next or previous variable. File: xemacs.info, Node: Locals, Next: File Variables, Prev: Edit Options, Up: Variables Local Variables --------------- `M-x make-local-variable' Make a variable have a local value in the current buffer. `M-x kill-local-variable' Make a variable use its global value in the current buffer. `M-x make-variable-buffer-local' Mark a variable so that setting it will make it local to the buffer that is current at that time. You can make any variable "local" to a specific Emacs buffer. This means that the variable's value in that buffer is independent of its value in other buffers. A few variables are always local in every buffer. All other Emacs variables have a "global" value which is in effect in all buffers that have not made the variable local. Major modes always make the variables they set local to the buffer. This is why changing major modes in one buffer has no effect on other buffers. `M-x make-local-variable' reads the name of a variable and makes it local to the current buffer. Further changes in this buffer will not affect others, and changes in the global value will not affect this buffer. `M-x make-variable-buffer-local' reads the name of a variable and changes the future behavior of the variable so that it automatically becomes local when it is set. More precisely, once you have marked a variable in this way, the usual ways of setting the variable will automatically invoke `make-local-variable' first. We call such variables "per-buffer" variables. Some important variables have been marked per-buffer already. They include `abbrev-mode', `auto-fill-function', `case-fold-search', `comment-column', `ctl-arrow', `fill-column', `fill-prefix', `indent-tabs-mode', `left-margin', `mode-line-format', `overwrite-mode', `selective-display-ellipses', `selective-display', `tab-width', and `truncate-lines'. Some other variables are always local in every buffer, but they are used for internal purposes. Note: the variable `auto-fill-function' was formerly named `auto-fill-hook'. If you want a variable to cease to be local to the current buffer, call `M-x kill-local-variable' and provide the name of a variable to the prompt. The global value of the variable is again in effect in this buffer. Setting the major mode kills all the local variables of the buffer. To set the global value of a variable, regardless of whether the variable has a local value in the current buffer, you can use the Lisp function `setq-default'. It works like `setq'. If there is a local value in the current buffer, the local value is not affected by `setq-default'; thus, the new global value may not be visible until you switch to another buffer, as in the case of: (setq-default fill-column 75) `setq-default' is the only way to set the global value of a variable that has been marked with `make-variable-buffer-local'. Programs can look at a variable's default value with `default-value'. This function takes a symbol as an argument and returns its default value. The argument is evaluated; usually you must quote it explicitly, as in the case of: (default-value 'fill-column) File: xemacs.info, Node: File Variables, Prev: Locals, Up: Variables Local Variables in Files ------------------------ A file can contain a "local variables list", which specifies the values to use for certain Emacs variables when that file is edited. Visiting the file checks for a local variables list and makes each variable in the list local to the buffer in which the file is visited, with the value specified in the file. A local variables list goes near the end of the file, in the last page. (It is often best to put it on a page by itself.) The local variables list starts with a line containing the string `Local Variables:', and ends with a line containing the string `End:'. In between come the variable names and values, one set per line, as `VARIABLE: VALUE'. The VALUEs are not evaluated; they are used literally. The line which starts the local variables list does not have to say just `Local Variables:'. If there is other text before `Local Variables:', that text is called the "prefix", and if there is other text after, that is called the "suffix". If a prefix or suffix are present, each entry in the local variables list should have the prefix before it and the suffix after it. This includes the `End:' line. The prefix and suffix are included to disguise the local variables list as a comment so the compiler or text formatter will ignore it. If you do not need to disguise the local variables list as a comment in this way, there is no need to include a prefix or a suffix. Two "variable" names are special in a local variables list: a value for the variable `mode' sets the major mode, and a value for the variable `eval' is simply evaluated as an expression and the value is ignored. These are not real variables; setting them in any other context does not have the same effect. If `mode' is used in a local variables list, it should be the first entry in the list. Here is an example of a local variables list: ;;; Local Variables: *** ;;; mode:lisp *** ;;; comment-column:0 *** ;;; comment-start: ";;; " *** ;;; comment-end:"***" *** ;;; End: *** Note that the prefix is `;;; ' and the suffix is ` ***'. Note also that comments in the file begin with and end with the same strings. Presumably the file contains code in a language which is enough like Lisp for Lisp mode to be useful but in which comments start and end differently. The prefix and suffix are used in the local variables list to make the list look like several lines of comments when the compiler or interpreter for that language reads the file. The start of the local variables list must be no more than 3000 characters from the end of the file, and must be in the last page if the file is divided into pages. Otherwise, Emacs will not notice it is there. The purpose is twofold: a stray `Local Variables:' not in the last page does not confuse Emacs, and Emacs never needs to search a long file that contains no page markers and has no local variables list. You may be tempted to turn on Auto Fill mode with a local variable list. That is inappropriate. Whether you use Auto Fill mode or not is a matter of personal taste, not a matter of the contents of particular files. If you want to use Auto Fill, set up major mode hooks with your `.emacs' file to turn it on (when appropriate) for you alone (*note Init File::.). Don't try to use a local variable list that would impose your taste on everyone working with the file. XEmacs allows you to specify local variables in the first line of a file, in addition to specifying them in the `Local Variables' section at the end of a file. If the first line of a file contains two occurences of ``-*-'', Emacs uses the information between them to determine what the major mode and variable settings should be. For example, these are all legal: ;;; -*- mode: emacs-lisp -*- ;;; -*- mode: postscript; version-control: never -*- ;;; -*- tags-file-name: "/foo/bar/TAGS" -*- For historical reasons, the syntax ``-*- modename -*-'' is allowed as well; for example, you can use: ;;; -*- emacs-lisp -*- The variable `enable-local-variables' controls the use of local variables lists in files you visit. The value can be `t', `nil', or something else. A value of `t' means local variables lists are obeyed; `nil' means they are ignored; anything else means query. The command `M-x normal-mode' always obeys local variables lists and ignores this variable. File: xemacs.info, Node: Keyboard Macros, Next: Key Bindings, Prev: Variables, Up: Customization Keyboard Macros =============== A "keyboard macro" is a command defined by the user to abbreviate a sequence of keys. For example, if you discover that you are about to type `C-n C-d' forty times, you can speed your work by defining a keyboard macro to invoke `C-n C-d' and calling it with a repeat count of forty. `C-x (' Start defining a keyboard macro (`start-kbd-macro'). `C-x )' End the definition of a keyboard macro (`end-kbd-macro'). `C-x e' Execute the most recent keyboard macro (`call-last-kbd-macro'). `C-u C-x (' Re-execute last keyboard macro, then add more keys to its definition. `C-x q' When this point is reached during macro execution, ask for confirmation (`kbd-macro-query'). `M-x name-last-kbd-macro' Give a command name (for the duration of the session) to the most recently defined keyboard macro. `M-x insert-kbd-macro' Insert in the buffer a keyboard macro's definition, as Lisp code. Keyboard macros differ from other Emacs commands in that they are written in the Emacs command language rather than in Lisp. This makes it easier for the novice to write them and makes them more convenient as temporary hacks. However, the Emacs command language is not powerful enough as a programming language to be useful for writing anything general or complex. For such things, Lisp must be used. You define a keyboard macro by executing the commands which are its definition. Put differently, as you are defining a keyboard macro, the definition is being executed for the first time. This way, you see what the effects of your commands are, and don't have to figure them out in your head. When you are finished, the keyboard macro is defined and also has been executed once. You can then execute the same set of commands again by invoking the macro. * Menu: * Basic Kbd Macro:: Defining and running keyboard macros. * Save Kbd Macro:: Giving keyboard macros names; saving them in files. * Kbd Macro Query:: Keyboard macros that do different things each use. File: xemacs.info, Node: Basic Kbd Macro, Next: Save Kbd Macro, Up: Keyboard Macros Basic Use --------- To start defining a keyboard macro, type `C-x (' (`start-kbd-macro'). From then on, anything you type continues to be executed, but also becomes part of the definition of the macro. `Def' appears in the mode line to remind you of what is going on. When you are finished, the `C-x )' command (`end-kbd-macro') terminates the definition, without becoming part of it. For example, C-x ( M-f foo C-x ) defines a macro to move forward a word and then insert `foo'. You can give `C-x )' a repeat count as an argument, in which case it repeats the macro that many times right after defining it, but defining the macro counts as the first repetition (since it is executed as you define it). If you give `C-x )' an argument of 4, it executes the macro immediately 3 additional times. An argument of zero to `C-x e' or `C-x )' means repeat the macro indefinitely (until it gets an error or you type `C-g'). Once you have defined a macro, you can invoke it again with the `C-x e' command (`call-last-kbd-macro'). You can give the command a repeat count numeric argument to execute the macro many times. To repeat an operation at regularly spaced places in the text, define a macro and include as part of the macro the commands to move to the next place you want to use it. For example, if you want to change each line, you should position point at the start of a line, and define a macro to change that line and leave point at the start of the next line. Repeating the macro will then operate on successive lines. After you have terminated the definition of a keyboard macro, you can add to the end of its definition by typing `C-u C-x ('. This is equivalent to plain `C-x (' followed by retyping the whole definition so far. As a consequence it re-executes the macro as previously defined. File: xemacs.info, Node: Save Kbd Macro, Next: Kbd Macro Query, Prev: Basic Kbd Macro, Up: Keyboard Macros Naming and Saving Keyboard Macros --------------------------------- To save a keyboard macro for longer than until you define the next one, you must give it a name using `M-x name-last-kbd-macro'. This reads a name as an argument using the minibuffer and defines that name to execute the macro. The macro name is a Lisp symbol, and defining it in this way makes it a valid command name for calling with `M-x' or for binding a key to with `global-set-key' (*note Keymaps::.). If you specify a name that has a prior definition other than another keyboard macro, Emacs prints an error message and nothing is changed. Once a macro has a command name, you can save its definition in a file. You can then use it in another editing session. First visit the file you want to save the definition in. Then use the command: M-x insert-kbd-macro RET MACRONAME RET This inserts some Lisp code that, when executed later, will define the same macro with the same definition it has now. You need not understand Lisp code to do this, because `insert-kbd-macro' writes the Lisp code for you. Then save the file. You can load the file with `load-file' (*note Lisp Libraries::.). If the file you save in is your initialization file `~/.emacs' (*note Init File::.), then the macro will be defined each time you run Emacs. If you give `insert-kbd-macro' a prefix argument, it creates additional Lisp code to record the keys (if any) that you have bound to the keyboard macro, so that the macro is reassigned the same keys when you load the file. File: xemacs.info, Node: Kbd Macro Query, Prev: Save Kbd Macro, Up: Keyboard Macros Executing Macros With Variations -------------------------------- You can use `C-x q' (`kbd-macro-query'), to get an effect similar to that of `query-replace'. The macro asks you each time whether to make a change. When you are defining the macro, type `C-x q' at the point where you want the query to occur. During macro definition, the `C-x q' does nothing, but when you invoke the macro, `C-x q' reads a character from the terminal to decide whether to continue. The special answers to a `C-x q' query are SPC, DEL, `C-d', `C-l', and `C-r'. Any other character terminates execution of the keyboard macro and is then read as a command. SPC means to continue. DEL means to skip the remainder of this repetition of the macro, starting again from the beginning in the next repetition. `C-d' means to skip the remainder of this repetition and cancel further repetition. `C-l' redraws the frame and asks you again for a character to specify what to do. `C-r' enters a recursive editing level, in which you can perform editing that is not part of the macro. When you exit the recursive edit using `C-M-c', you are asked again how to continue with the keyboard macro. If you type a SPC at this time, the rest of the macro definition is executed. It is up to you to leave point and the text in a state such that the rest of the macro will do what you want. `C-u C-x q', which is `C-x q' with a numeric argument, performs a different function. It enters a recursive edit reading input from the keyboard, both when you type it during the definition of the macro and when it is executed from the macro. During definition, the editing you do inside the recursive edit does not become part of the macro. During macro execution, the recursive edit gives you a chance to do some particularized editing. *Note Recursive Edit::. File: xemacs.info, Node: Key Bindings, Next: Syntax, Prev: Keyboard Macros, Up: Customization Customizing Key Bindings ======================== This section deals with the "keymaps" that define the bindings between keys and functions, and shows how you can customize these bindings. A command is a Lisp function whose definition provides for interactive use. Like every Lisp function, a command has a function name, which is a Lisp symbol whose name usually consists of lower case letters and hyphens. * Menu: * Keymaps:: Definition of the keymap data structure. Names of Emacs's standard keymaps. * Rebinding:: How to redefine one key's meaning conveniently. * Disabling:: Disabling a command means confirmation is required before it can be executed. This is done to protect beginners from surprises. File: xemacs.info, Node: Keymaps, Next: Rebinding, Up: Key Bindings Keymaps ------- The bindings between characters and command functions are recorded in data structures called "keymaps". Emacs has many of these. One, the "global" keymap, defines the meanings of the single-character keys that are defined regardless of major mode. It is the value of the variable `global-map'. Each major mode has another keymap, its "local keymap", which contains overriding definitions for the single-character keys that are redefined in that mode. Each buffer records which local keymap is installed for it at any time, and the current buffer's local keymap is the only one that directly affects command execution. The local keymaps for Lisp mode, C mode, and many other major modes always exist even when not in use. They are the values of the variables `lisp-mode-map', `c-mode-map', and so on. For less frequently used major modes, the local keymap is sometimes constructed only when the mode is used for the first time in a session, to save space. There are local keymaps for the minibuffer, too; they contain various completion and exit commands. * `minibuffer-local-map' is used for ordinary input (no completion). * `minibuffer-local-ns-map' is similar, except that SPC exits just like RET. This is used mainly for Mocklisp compatibility. * `minibuffer-local-completion-map' is for permissive completion. * `minibuffer-local-must-match-map' is for strict completion and for cautious completion. * `repeat-complex-command-map' is for use in `C-x ESC'. * `isearch-mode-map' contains the bindings of the special keys which are bound in the pseudo-mode entered with `C-s' and `C-r'. Finally, each prefix key has a keymap which defines the key sequences that start with it. For example, `ctl-x-map' is the keymap used for characters following a `C-x'. * `ctl-x-map' is the variable name for the map used for characters that follow `C-x'. * `help-map' is used for characters that follow `C-h'. * `esc-map' is for characters that follow ESC. All Meta characters are actually defined by this map. * `ctl-x-4-map' is for characters that follow `C-x 4'. * `mode-specific-map' is for characters that follow `C-c'. The definition of a prefix key is the keymap to use for looking up the following character. Sometimes the definition is actually a Lisp symbol whose function definition is the following character keymap. The effect is the same, but it provides a command name for the prefix key that you can use as a description of what the prefix key is for. Thus the binding of `C-x' is the symbol `Ctl-X-Prefix', whose function definition is the keymap for `C-x' commands, the value of `ctl-x-map'. Prefix key definitions can appear in either the global map or a local map. The definitions of `C-c', `C-x', `C-h', and ESC as prefix keys appear in the global map, so these prefix keys are always available. Major modes can locally redefine a key as a prefix by putting a prefix key definition for it in the local map. A mode can also put a prefix definition of a global prefix character such as `C-x' into its local map. This is how major modes override the definitions of certain keys that start with `C-x'. This case is special, because the local definition does not entirely replace the global one. When both the global and local definitions of a key are other keymaps, the next character is looked up in both keymaps, with the local definition overriding the global one. The character after the `C-x' is looked up in both the major mode's own keymap for redefined `C-x' commands and in `ctl-x-map'. If the major mode's own keymap for `C-x' commands contains `nil', the definition from the global keymap for `C-x' commands is used. File: xemacs.info, Node: Rebinding, Next: Disabling, Prev: Keymaps, Up: Key Bindings Changing Key Bindings --------------------- You can redefine an Emacs key by changing 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. * Menu: * Interactive Rebinding:: Changing Key Bindings Interactively * Programmatic Rebinding:: Changing Key Bindings Programmatically * Key Bindings Using Strings::Using Strings for Changing Key Bindings File: xemacs.info, Node: Interactive Rebinding, Next: Programmatic Rebinding, Up: Rebinding Changing Key Bindings Interactively ................................... `M-x global-set-key RET KEY CMD RET' Defines KEY globally to run CMD. `M-x local-set-key RET KEYS CMD RET' Defines KEY locally (in the major mode now in effect) to run CMD. `M-x local-unset-key RET KEYS RET' Removes the local binding of KEY. CMD is a symbol naming an interactively-callable function. When called interactively, KEY is the next complete key sequence that you type. When called as a function, KEY is a string, a vector of events, or a vector of key-description lists as described in the `define-key' function description. The binding goes in the current buffer's local map, which is shared with other buffers in the same major mode. The following example: M-x global-set-key RET C-f next-line RET redefines `C-f' to move down a line. The fact that CMD is read second makes it serve as a kind of confirmation for KEY. These functions offer no way to specify a particular prefix keymap as the one to redefine in, but that is not necessary, as you can include prefixes in KEY. KEY is read by reading characters one by one until they amount to a complete key (that is, not a prefix key). Thus, if you type `C-f' for KEY, Emacs enters the minibuffer immediately to read CMD. But if you type `C-x', another character is read; if that character is `4', another character is read, and so on. For example, M-x global-set-key RET C-x 4 $ spell-other-window RET redefines `C-x 4 $' to run the (fictitious) command `spell-other-window'. The most general way to modify a keymap is the function `define-key', used in Lisp code (such as your `.emacs' file). `define-key' takes three arguments: the keymap, the key to modify in it, and the new definition. *Note Init File::, for an example. `substitute-key-definition' is used similarly; it takes three arguments, an old definition, a new definition, and a keymap, and redefines in that keymap all keys that were previously defined with the old definition to have the new definition instead.