3 This file documents the end user interface to the GNU command line
4 editing feautres. It is to be an appendix to manuals for programs which
5 use these features. There is a document entitled "readline.texinfo"
6 which contains both end-user and programmer documentation for the GNU
9 Copyright (C) 1988 Free Software Foundation, Inc.
11 Authored by Brian Fox.
13 Permission is granted to process this file through Tex and print the
14 results, provided the printed document carries copying permission notice
15 identical to this one except for the removal of this paragraph (this
16 paragraph not being relevant to the printed manual).
18 Permission is granted to make and distribute verbatim copies of this manual
19 provided the copyright notice and this permission notice are preserved on
22 Permission is granted to copy and distribute modified versions of this
23 manual under the conditions for verbatim copying, provided also that the
24 GNU Copyright statement is available to the distributee, and provided that
25 the entire resulting derived work is distributed under the terms of a
26 permission notice identical to this one.
28 Permission is granted to copy and distribute translations of this manual
29 into another language, under the above conditions for modified versions.
32 @appendix Command Line Editing
33 @node Command Line Editing, , , Top
35 This appendix describes GNU's command line editing interface.
38 * Introduction and Notation:: Notation used in this appendix.
39 * Basic Line Editing:: The minimum set of commands for editing a line.
40 * Movement Commands:: Commands for moving the cursor about the line.
41 * Cutting and Pasting:: Deletion and copying of text sections.
42 * Transposition:: Exchanging two characters or words.
43 * Completion:: Expansion of a partially typed word into
47 @node Readline Introduction, Readline Interaction, Readline Top, Readline Top
48 @section Introduction to Line Editing
50 Many programs read input from the user one line at a time. The GNU
51 Readline library provides Emacs style command line editing, and
52 interfaces directly with the GNU History library. @inforef{Top, History,
53 history.info}, for more information.
55 Readline uses a single initialization file, (@file{~/.inputrc}) which
56 means that any program which uses Readline will present your customized
57 version of Readline. @xref{Readline Init File} for details.
59 In this section of the manual, we use a special syntax to describe
62 The text @key{C-k} is read as `Control-K' and describes the character
63 produced when the Control key is depressed and the @key{k} key is struck.
65 The text @key{M-k} is read as `Meta-K' and describes the character
66 produced when the meta key (if you have one) is depressed, and the @key{k}
67 key is struck. If you do not have a meta key, the identical keystroke
68 can be generated by typing @key{ESC} @i{first}, and then typing @key{k}.
69 Either process is known as @dfn{metafying} the @key{k} key.
71 The text @key{M-C-k} is read as `Meta-Control-k' and describes the
72 character produced by @dfn{metafying} @key{C-k}.
74 In addition, several keys have their own names. Specifically,
75 @key{RUBOUT}, @key{DEL}, @key{ESC}, @key{NEWLINE}, @key{SPACE},
76 @key{RETURN}, @key{LFD}, and @key{TAB} all stand for themselves when
77 seen in this text, or in an init file (@pxref{Readline Init File}, for
80 @node Readline Interaction, Readline Init File, Readline Introduction, Readline Top
81 @section Readline Interaction
82 @cindex interaction, readline
84 Often during an interactive session you will type in a long line of
85 text, only to notice that the first word on the line is misspelled. The
86 Readline library gives you a set of commands for manipulating the text
87 as you type it in, allowing you to just fix your typo, and not forcing
88 you to retype the majority of the line. Using these editing commands,
89 you move the cursor to the place that needs correction, and delete or
90 insert the text of the corrections. Then, when you are satisfied with
91 the line, you simply press @key{RETURN}. You do not have to be at the
92 end of the line to press @key{RETURN}; the entire line will be accepted
96 * Readline Bare Essentials:: The least you need to know about Readline.
97 * Readline Movement Commands:: Moving about the input line.
98 * Readline Killing Commands:: How to delete text, and how to get it back!
99 * Readline Arguments:: Giving numeric arguments to commands.
102 @node Readline Bare Essentials, Readline Movement Commands, Readline Interaction, Readline Interaction
103 @subsection Readline Bare Essentials
105 As you type text into the line, you will notice that characters to the
106 right of the cursor get `pushed over' to make room for the characters
107 that you are typing. Likewise, when you delete a character behind the
108 cursor, characters to the right of the cursor get `pulled back' to fill
109 in the blank space created by the removal of the character. There is no
110 `overwrite mode' provided by Readline; all characters are inserted.
112 Here are the basic bare essentials for editing the text of an input line.
116 Move back one character.
118 Move forward one character.
120 Delete the character underneath the cursor.
122 Delete the character to the left of the cursor.
123 @item printing character
124 Insert itself into the line at the cursor.
126 Undo the last thing that you did. You can undo all the way back to an
130 @node Readline Movement Commands, Readline Killing Commands, Readline Bare Essentials, Readline Interaction
131 @subsection Readline Movement Commands
133 The above table described the most basic possible keystrokes that you
134 would need in order to do editing of the input line. For your
135 convenience, many other commands have been added in addition to
136 @key{C-b}, @key{C-f}, @key{C-d}, and @key{DEL}. Here are some
137 commands for moving more rapidly about the line.
141 Move to the start of the line.
143 Move to the end of the line.
147 Move backward a word.
149 Clear the screen, reprinting the current line at the top.
152 Notice how @key{C-f} moves forward a character, while @key{M-f} moves
153 forward a word? It is a loose convention that control keystrokes
154 operate on characters while meta keystrokes operate on words.
156 @node Readline Killing Commands, Readline Arguments, Readline Movement Commands, Readline Interaction
157 @subsection Readline Killing Commands
159 Now that we know how to move about the line, we might be interested in
160 performing more sophisticated operations, such as moving a word from the
161 front of the line to the end, or removing a mistyped argument to a
164 @dfn{Killing} text means to delete the text from the line, but to save
165 it away for later use, usually by @dfn{yanking} it back into the line.
166 If the description for a command says that it `kills' text, then you can
167 be sure that you can get the text back in a different (or the same)
170 Here is the list of commands for killing text.
174 Kill the text from the current cursor position to the end of the line.
177 Kill from the cursor to the end of the current word, or if between
178 words, to the end of the next word.
181 Kill from the cursor to the start of the current word, or if between
182 words, to the start of the previous word.
185 Kill from the cursor to the previous whitespace. This is different than
186 @key{M-DEL} because the word boundaries differ.
190 And, here is how to @dfn{yank} the text back into the line.
194 Yank the most recently killed text back into the buffer at the cursor.
197 Rotate the kill-ring, and yank the new top. You can only do this if
198 the prior command is @key{C-y} or @key{M-y}.
201 When you use a kill command, the text is saved in a @dfn{kill-ring}.
202 Any number of consecutive kills save all of the killed text together, so
203 that when you yank it back, you get it in one clean sweep. The kill
204 ring is not line specific; the text that you killed on a previously
205 typed line is available to be yanked back later, when you are typing
208 @node Readline Arguments, , Readline Killing Commands, Readline Interaction
209 @subsection Readline Arguments
211 You can pass numeric arguments to Readline commands. Sometimes the
212 argument acts as a repeat count, other times it is the @i{sign} of the
213 argument that is significant. If you pass a negative argument to a
214 command which normally acts in a forward direction, that command will
215 act in a backward direction. For example, to kill text back to the
216 start of the line, you might type @key{M--} @key{C-k}.
218 The general way to pass numeric arguments to a command is to type meta
219 digits before the command. If the first `digit' you type is a minus
220 sign (@key{-}), then the sign of the argument will be negative. Once
221 you have typed one meta digit to get the argument started, you can type
222 the remainder of the digits, and then the command. For example, to give
223 the @key{C-d} command an argument of 10, you could type @key{M-1 0 C-d}.
226 @node Readline Init File, , Readline Interaction, Readline Top
227 @section Readline Init File
229 Although the Readline library comes with a set of Emacs-like
230 keybindings, it is possible that you would like to use a different set
231 of keybindings. You can customize programs that use Readline by putting
232 commands in an @dfn{init} file in your home directory. The name of this
233 file is @file{~/.inputrc}.
235 When a program which uses the Readline library starts up, the
236 @file{~/.inputrc} file is read, and the keybindings are set.
239 * Readline Init Syntax:: Syntax for the commands in @file{~/.inputrc}.
240 * Readline Vi Mode:: Switching to @code{vi} mode in Readline.
243 @node Readline Init Syntax, Readline Vi Mode, Readline Init File, Readline Init File
244 @subsection Readline Init Syntax
246 You can start up with a vi-like editing mode by placing
249 @code{set editing-mode vi}
252 in your @file{~/.inputrc} file.
254 You can have Readline use a single line for display, scrolling the input
255 between the two edges of the screen by placing
258 @code{set horizontal-scroll-mode On}
261 in your @file{~/.inputrc} file.
263 The syntax for controlling keybindings in the @file{~/.inputrc} file is
264 simple. First you have to know the @i{name} of the command that you
265 want to change. The following pages contain tables of the command name, the
266 default keybinding, and a short description of what the command does.
268 Once you know the name of the command, simply place the name of the key
269 you wish to bind the command to, a colon, and then the name of the
270 command on a line in the @file{~/.inputrc} file. Here is an example:
273 # This is a comment line.
274 Meta-Rubout: backward-kill-word
275 Control-u: universal-argument
279 * Commands For Moving:: Moving about the line.
280 * Commands For History:: Getting at previous lines.
281 * Commands For Text:: Commands for changing text.
282 * Commands For Killing:: Commands for killing and yanking.
283 * Numeric Arguments:: Specifying numeric arguments, repeat counts.
284 * Commands For Completion:: Getting Readline to do the typing for you.
285 * Miscellaneous Commands:: Other miscillaneous commands.
288 @node Commands For Moving, Commands For History, Readline Init Syntax, Readline Init Syntax
289 @subsubsection Commands For Moving
291 @item beginning-of-line (C-a)
292 Move to the start of the current line.
294 @item end-of-line (C-e)
295 Move to the end of the line.
297 @item forward-char (C-f)
298 Move forward a character.
300 @item backward-char (C-b)
301 Move back a character.
303 @item forward-word (M-f)
304 Move forward to the end of the next word.
306 @item backward-word (M-b)
307 Move back to the start of this, or the previous, word.
309 @item clear-screen (C-l)
310 Clear the screen leaving the current line at the top of the screen.
314 @node Commands For History, Commands For Text, Commands For Moving, Readline Init Syntax
315 @subsubsection Commands For Manipulating The History
318 @item accept-line (Newline, Return)
319 Accept the line regardless of where the cursor is. If this line is
320 non-empty, add it too the history list. If this line was a history
321 line, then restore the history line to its original state.
323 @item previous-history (C-p)
324 Move `up' through the history list.
326 @item next-history (C-n)
327 Move `down' through the history list.
329 @item beginning-of-history (M-<)
330 Move to the first line in the history.
332 @item end-of-history (M->)
333 Move to the end of the input history, i.e., the line you are entering!
335 @item reverse-search-history (C-r)
336 Search backward starting at the current line and moving `up' through
337 the history as necessary. This is an incremental search.
339 @item forward-search-history (C-s)
340 Search forward starting at the current line and moving `down' through
341 the the history as neccessary.
345 @node Commands For Text, Commands For Killing, Commands For History, Readline Init Syntax
346 @subsubsection Commands For Changing Text
349 @item delete-char (C-d)
350 Delete the character under the cursor. If the cursor is at the
351 beginning of the line, and there are no characters in the line, and
352 the last character typed was not C-d, then return EOF.
354 @item backward-delete-char (Rubout)
355 Delete the character behind the cursor. A numeric arg says to kill
356 the characters instead of deleting them.
358 @item quoted-insert (C-q, C-v)
359 Add the next character that you type to the line verbatim. This is
360 how to insert things like C-q for example.
362 @item tab-insert (M-TAB)
363 Insert a tab character.
365 @item self-insert (a, b, A, 1, !, ...)
368 @item transpose-chars (C-t)
369 Drag the character before point forward over the character at point.
370 Point moves forward as well. If point is at the end of the line, then
371 transpose the two characters before point. Negative args don't work.
373 @item transpose-words (M-t)
374 Drag the word behind the cursor past the word in front of the cursor
375 moving the cursor over that word as well.
377 @item upcase-word (M-u)
378 Uppercase the current (or following) word. With a negative argument,
379 do the previous word, but do not move point.
381 @item downcase-word (M-l)
382 Lowercase the current (or following) word. With a negative argument,
383 do the previous word, but do not move point.
385 @item capitalize-word (M-c)
386 Uppercase the current (or following) word. With a negative argument,
387 do the previous word, but do not move point.
391 @node Commands For Killing, Numeric Arguments, Commands For Text, Readline Init Syntax
392 @subsubsection Killing And Yanking
396 @item kill-line (C-k)
397 Kill the text from the current cursor position to the end of the line.
399 @item backward-kill-line ()
400 Kill backward to the beginning of the line. This is normally unbound.
402 @item kill-word (M-d)
403 Kill from the cursor to the end of the current word, or if between
404 words, to the end of the next word.
406 @item backward-kill-word (M-DEL)
407 Kill the word behind the cursor.
409 @item unix-line-discard (C-u)
410 Do what C-u used to do in Unix line input. We save the killed text on
411 the kill-ring, though.
413 @item unix-word-rubout (C-w)
414 Do what C-w used to do in Unix line input. The killed text is saved
415 on the kill-ring. This is different than backward-kill-word because
416 the word boundaries differ.
419 Yank the top of the kill ring into the buffer at point.
422 Rotate the kill-ring, and yank the new top. You can only do this if
423 the prior command is yank or yank-pop.
426 @node Numeric Arguments, Commands For Completion, Commands For Killing, Readline Init Syntax
427 @subsubsection Specifying Numeric Arguments
430 @item digit-argument (M-0, M-1, ... M--)
431 Add this digit to the argument already accumulating, or start a new
432 argument. M-- starts a negative argument.
434 @item universal-argument ()
435 Do what C-u does in emacs. By default, this is not bound.
439 @node Commands For Completion, Miscellaneous Commands, Numeric Arguments, Readline Init Syntax
440 @subsubsection Letting Readline Type For You
444 Attempt to do completion on the text before point. This is
445 implementation defined. Generally, if you are typing a filename
446 argument, you can do filename completion; if you are typing a command,
447 you can do command completion, if you are typing in a symbol to GDB, you
448 can do symbol name completion, if you are typing in a variable to Bash,
449 you can do variable name completion...
451 @item possible-completions (M-?)
452 List the possible completions of the text before point.
455 @node Miscellaneous Commands, , Commands For Completion, Readline Init Syntax
456 @subsubsection Some Miscellaneous Commands
462 @item do-uppercase-version (M-a, M-b, ...)
463 Run the command that is bound to your uppercase brother.
465 @item prefix-meta (ESC)
466 Make the next character that you type be metafied. This is for
467 people without a meta key. @key{ESC-f} is equivalent to @key{M-f}.
470 Incremental undo, separately remembered for each line.
472 @item revert-line (M-r)
473 Undo all changes made to this line. This is like typing the `undo'
474 command enough times to get back to the beginning.
477 @node Readline Vi Mode, , Readline Init Syntax, Readline Init File
478 @subsection Readline Vi Mode
480 While the Readline library does not have a full set of Vi editing
481 functions, it does contain enough to allow simple editing of the line.
483 In order to switch interactively between Emacs and Vi editing modes, use
484 the command M-C-j (toggle-editing-mode).
486 When you enter a line in Vi mode, you are already placed in `insertion'
487 mode, as if you had typed an `i'. Pressing @key{ESC} switches you into
488 `edit' mode, where you can edit the text of the line with the standard
489 Vi movement keys, move to previous history lines with `k', and following
490 lines with `j', and so forth.