1READLINE(3) Library Functions Manual READLINE(3)
2
3
4
6 readline - get a line from a user with editing
7
9 #include <stdio.h>
10 #include <readline/readline.h>
11 #include <readline/history.h>
12
13 char *
14 readline (const char *prompt);
15
17 Readline is Copyright (C) 1989-2020 Free Software Foundation, Inc.
18
20 readline will read a line from the terminal and return it, using prompt
21 as a prompt. If prompt is NULL or the empty string, no prompt is is‐
22 sued. The line returned is allocated with malloc(3); the caller must
23 free it when finished. The line returned has the final newline re‐
24 moved, so only the text of the line remains.
25
26 readline offers editing capabilities while the user is entering the
27 line. By default, the line editing commands are similar to those of
28 emacs. A vi-style line editing interface is also available.
29
30 This manual page describes only the most basic use of readline. Much
31 more functionality is available; see The GNU Readline Library and The
32 GNU History Library for additional information.
33
35 readline returns the text of the line read. A blank line returns the
36 empty string. If EOF is encountered while reading a line, and the line
37 is empty, NULL is returned. If an EOF is read with a non-empty line,
38 it is treated as a newline.
39
41 An Emacs-style notation is used to denote keystrokes. Control keys are
42 denoted by C-key, e.g., C-n means Control-N. Similarly, meta keys are
43 denoted by M-key, so M-x means Meta-X. (On keyboards without a meta
44 key, M-x means ESC x, i.e., press the Escape key then the x key. This
45 makes ESC the meta prefix. The combination M-C-x means ESC-Control-x,
46 or press the Escape key then hold the Control key while pressing the x
47 key.)
48
49 Readline commands may be given numeric arguments, which normally act as
50 a repeat count. Sometimes, however, it is the sign of the argument
51 that is significant. Passing a negative argument to a command that
52 acts in the forward direction (e.g., kill-line) causes that command to
53 act in a backward direction. Commands whose behavior with arguments
54 deviates from this are noted below.
55
56 When a command is described as killing text, the text deleted is saved
57 for possible future retrieval (yanking). The killed text is saved in a
58 kill ring. Consecutive kills cause the text to be accumulated into one
59 unit, which can be yanked all at once. Commands which do not kill text
60 separate the chunks of text on the kill ring.
61
63 Readline is customized by putting commands in an initialization file
64 (the inputrc file). The name of this file is taken from the value of
65 the INPUTRC environment variable. If that variable is unset, the de‐
66 fault is ~/.inputrc. If that file does not exist or cannot be read,
67 the ultimate default is /etc/inputrc. When a program which uses the
68 readline library starts up, the init file is read, and the key bindings
69 and variables are set. There are only a few basic constructs allowed
70 in the readline init file. Blank lines are ignored. Lines beginning
71 with a # are comments. Lines beginning with a $ indicate conditional
72 constructs. Other lines denote key bindings and variable settings.
73 Each program using this library may add its own commands and bindings.
74
75 For example, placing
76
77 M-Control-u: universal-argument
78 or
79 C-Meta-u: universal-argument
80
81 into the inputrc would make M-C-u execute the readline command univer‐
82 sal-argument.
83
84 The following symbolic character names are recognized while processing
85 key bindings: DEL, ESC, ESCAPE, LFD, NEWLINE, RET, RETURN, RUBOUT,
86 SPACE, SPC, and TAB.
87
88 In addition to command names, readline allows keys to be bound to a
89 string that is inserted when the key is pressed (a macro).
90
91 Key Bindings
92 The syntax for controlling key bindings in the inputrc file is simple.
93 All that is required is the name of the command or the text of a macro
94 and a key sequence to which it should be bound. The name may be speci‐
95 fied in one of two ways: as a symbolic key name, possibly with Meta- or
96 Control- prefixes, or as a key sequence. The name and key sequence are
97 separated by a colon. There can be no whitespace between the name and
98 the colon.
99
100 When using the form keyname:function-name or macro, keyname is the name
101 of a key spelled out in English. For example:
102
103 Control-u: universal-argument
104 Meta-Rubout: backward-kill-word
105 Control-o: "> output"
106
107 In the above example, C-u is bound to the function universal-argument,
108 M-DEL is bound to the function backward-kill-word, and C-o is bound to
109 run the macro expressed on the right hand side (that is, to insert the
110 text ``> output'' into the line).
111
112 In the second form, "keyseq":function-name or macro, keyseq differs
113 from keyname above in that strings denoting an entire key sequence may
114 be specified by placing the sequence within double quotes. Some GNU
115 Emacs style key escapes can be used, as in the following example, but
116 the symbolic character names are not recognized.
117
118 "\C-u": universal-argument
119 "\C-x\C-r": re-read-init-file
120 "\e[11~": "Function Key 1"
121
122 In this example, C-u is again bound to the function universal-argument.
123 C-x C-r is bound to the function re-read-init-file, and ESC [ 1 1 ~ is
124 bound to insert the text ``Function Key 1''.
125
126 The full set of GNU Emacs style escape sequences available when speci‐
127 fying key sequences is
128 \C- control prefix
129 \M- meta prefix
130 \e an escape character
131 \\ backslash
132 \" literal ", a double quote
133 \' literal ', a single quote
134
135 In addition to the GNU Emacs style escape sequences, a second set of
136 backslash escapes is available:
137 \a alert (bell)
138 \b backspace
139 \d delete
140 \f form feed
141 \n newline
142 \r carriage return
143 \t horizontal tab
144 \v vertical tab
145 \nnn the eight-bit character whose value is the octal value
146 nnn (one to three digits)
147 \xHH the eight-bit character whose value is the hexadecimal
148 value HH (one or two hex digits)
149
150 When entering the text of a macro, single or double quotes should be
151 used to indicate a macro definition. Unquoted text is assumed to be a
152 function name. In the macro body, the backslash escapes described
153 above are expanded. Backslash will quote any other character in the
154 macro text, including " and '.
155
156 Bash allows the current readline key bindings to be displayed or modi‐
157 fied with the bind builtin command. The editing mode may be switched
158 during interactive use by using the -o option to the set builtin com‐
159 mand. Other programs using this library provide similar mechanisms.
160 The inputrc file may be edited and re-read if a program does not pro‐
161 vide any other means to incorporate new bindings.
162
163 Variables
164 Readline has variables that can be used to further customize its behav‐
165 ior. A variable may be set in the inputrc file with a statement of the
166 form
167
168 set variable-name value
169
170 Except where noted, readline variables can take the values On or Off
171 (without regard to case). Unrecognized variable names are ignored.
172 When a variable value is read, empty or null values, "on" (case-insen‐
173 sitive), and "1" are equivalent to On. All other values are equivalent
174 to Off. The variables and their default values are:
175
176 active-region-start-color
177 A string variable that controls the text color and background
178 when displaying the text in the active region (see the descrip‐
179 tion of enable-active-region below). This string must not take
180 up any physical character positions on the display, so it should
181 consist only of terminal escape sequences. It is output to the
182 terminal before displaying the text in the active region. This
183 variable is reset to the default value whenever the terminal
184 type changes. The default value is the string that puts the
185 terminal in standout mode, as obtained from the terminal's ter‐
186 minfo description. A sample value might be "\e[01;33m".
187 active-region-end-color
188 A string variable that "undoes" the effects of active-re‐
189 gion-start-color and restores "normal" terminal display appear‐
190 ance after displaying text in the active region. This string
191 must not take up any physical character positions on the dis‐
192 play, so it should consist only of terminal escape sequences.
193 It is output to the terminal after displaying the text in the
194 active region. This variable is reset to the default value
195 whenever the terminal type changes. The default value is the
196 string that restores the terminal from standout mode, as ob‐
197 tained from the terminal's terminfo description. A sample value
198 might be "\e[0m".
199 bell-style (audible)
200 Controls what happens when readline wants to ring the terminal
201 bell. If set to none, readline never rings the bell. If set to
202 visible, readline uses a visible bell if one is available. If
203 set to audible, readline attempts to ring the terminal's bell.
204 bind-tty-special-chars (On)
205 If set to On (the default), readline attempts to bind the con‐
206 trol characters treated specially by the kernel's terminal
207 driver to their readline equivalents.
208 blink-matching-paren (Off)
209 If set to On, readline attempts to briefly move the cursor to an
210 opening parenthesis when a closing parenthesis is inserted.
211 colored-completion-prefix (Off)
212 If set to On, when listing completions, readline displays the
213 common prefix of the set of possible completions using a differ‐
214 ent color. The color definitions are taken from the value of
215 the LS_COLORS environment variable. If there is a color defini‐
216 tion in $LS_COLORS for the custom suffix "readline-colored-com‐
217 pletion-prefix", readline uses this color for the common prefix
218 instead of its default.
219 colored-stats (Off)
220 If set to On, readline displays possible completions using dif‐
221 ferent colors to indicate their file type. The color defini‐
222 tions are taken from the value of the LS_COLORS environment
223 variable.
224 comment-begin (``#'')
225 The string that is inserted in vi mode when the insert-comment
226 command is executed. This command is bound to M-# in emacs mode
227 and to # in vi command mode.
228 completion-display-width (-1)
229 The number of screen columns used to display possible matches
230 when performing completion. The value is ignored if it is less
231 than 0 or greater than the terminal screen width. A value of 0
232 will cause matches to be displayed one per line. The default
233 value is -1.
234 completion-ignore-case (Off)
235 If set to On, readline performs filename matching and completion
236 in a case-insensitive fashion.
237 completion-map-case (Off)
238 If set to On, and completion-ignore-case is enabled, readline
239 treats hyphens (-) and underscores (_) as equivalent when per‐
240 forming case-insensitive filename matching and completion.
241 completion-prefix-display-length (0)
242 The length in characters of the common prefix of a list of pos‐
243 sible completions that is displayed without modification. When
244 set to a value greater than zero, common prefixes longer than
245 this value are replaced with an ellipsis when displaying possi‐
246 ble completions.
247 completion-query-items (100)
248 This determines when the user is queried about viewing the num‐
249 ber of possible completions generated by the possible-comple‐
250 tions command. It may be set to any integer value greater than
251 or equal to zero. If the number of possible completions is
252 greater than or equal to the value of this variable, readline
253 will ask whether or not the user wishes to view them; otherwise
254 they are simply listed on the terminal. A negative value causes
255 readline to never ask.
256 convert-meta (On)
257 If set to On, readline will convert characters with the eighth
258 bit set to an ASCII key sequence by stripping the eighth bit and
259 prefixing it with an escape character (in effect, using escape
260 as the meta prefix). The default is On, but readline will set
261 it to Off if the locale contains eight-bit characters. This
262 variable is dependent on the LC_CTYPE locale category, and may
263 change if the locale is changed.
264 disable-completion (Off)
265 If set to On, readline will inhibit word completion. Completion
266 characters will be inserted into the line as if they had been
267 mapped to self-insert.
268 echo-control-characters (On)
269 When set to On, on operating systems that indicate they support
270 it, readline echoes a character corresponding to a signal gener‐
271 ated from the keyboard.
272 editing-mode (emacs)
273 Controls whether readline begins with a set of key bindings sim‐
274 ilar to Emacs or vi. editing-mode can be set to either emacs or
275 vi.
276 emacs-mode-string (@)
277 If the show-mode-in-prompt variable is enabled, this string is
278 displayed immediately before the last line of the primary prompt
279 when emacs editing mode is active. The value is expanded like a
280 key binding, so the standard set of meta- and control prefixes
281 and backslash escape sequences is available. Use the \1 and \2
282 escapes to begin and end sequences of non-printing characters,
283 which can be used to embed a terminal control sequence into the
284 mode string.
285 enable-active-region (On)
286 The point is the current cursor position, and mark refers to a
287 saved cursor position. The text between the point and mark is
288 referred to as the region. When this variable is set to On,
289 readline allows certain commands to designate the region as ac‐
290 tive. When the region is active, readline highlights the text
291 in the region using the value of the active-region-start-color,
292 which defaults to the string that enables the terminal's stand‐
293 out mode. The active region shows the text inserted by brack‐
294 eted-paste and any matching text found by incremental and non-
295 incremental history searches.
296 enable-bracketed-paste (On)
297 When set to On, readline configures the terminal to insert each
298 paste into the editing buffer as a single string of characters,
299 instead of treating each character as if it had been read from
300 the keyboard. This prevents readline from executing any editing
301 commands bound to key sequences appearing in the pasted text.
302 enable-keypad (Off)
303 When set to On, readline will try to enable the application key‐
304 pad when it is called. Some systems need this to enable the ar‐
305 row keys.
306 enable-meta-key (On)
307 When set to On, readline will try to enable any meta modifier
308 key the terminal claims to support when it is called. On many
309 terminals, the meta key is used to send eight-bit characters.
310 expand-tilde (Off)
311 If set to On, tilde expansion is performed when readline at‐
312 tempts word completion.
313 history-preserve-point (Off)
314 If set to On, the history code attempts to place point at the
315 same location on each history line retrieved with previous-his‐
316 tory or next-history.
317 history-size (unset)
318 Set the maximum number of history entries saved in the history
319 list. If set to zero, any existing history entries are deleted
320 and no new entries are saved. If set to a value less than zero,
321 the number of history entries is not limited. By default, the
322 number of history entries is not limited. If an attempt is made
323 to set history-size to a non-numeric value, the maximum number
324 of history entries will be set to 500.
325 horizontal-scroll-mode (Off)
326 When set to On, makes readline use a single line for display,
327 scrolling the input horizontally on a single screen line when it
328 becomes longer than the screen width rather than wrapping to a
329 new line. This setting is automatically enabled for terminals
330 of height 1.
331 input-meta (Off)
332 If set to On, readline will enable eight-bit input (that is, it
333 will not clear the eighth bit in the characters it reads), re‐
334 gardless of what the terminal claims it can support. The name
335 meta-flag is a synonym for this variable. The default is Off,
336 but readline will set it to On if the locale contains eight-bit
337 characters. This variable is dependent on the LC_CTYPE locale
338 category, and may change if the locale is changed.
339 isearch-terminators (``C-[ C-J'')
340 The string of characters that should terminate an incremental
341 search without subsequently executing the character as a com‐
342 mand. If this variable has not been given a value, the charac‐
343 ters ESC and C-J will terminate an incremental search.
344 keymap (emacs)
345 Set the current readline keymap. The set of legal keymap names
346 is emacs, emacs-standard, emacs-meta, emacs-ctlx, vi, vi-move,
347 vi-command, and vi-insert. vi is equivalent to vi-command;
348 emacs is equivalent to emacs-standard. The default value is
349 emacs. The value of editing-mode also affects the default
350 keymap.
351 keyseq-timeout (500)
352 Specifies the duration readline will wait for a character when
353 reading an ambiguous key sequence (one that can form a complete
354 key sequence using the input read so far, or can take additional
355 input to complete a longer key sequence). If no input is re‐
356 ceived within the timeout, readline will use the shorter but
357 complete key sequence. The value is specified in milliseconds,
358 so a value of 1000 means that readline will wait one second for
359 additional input. If this variable is set to a value less than
360 or equal to zero, or to a non-numeric value, readline will wait
361 until another key is pressed to decide which key sequence to
362 complete.
363 mark-directories (On)
364 If set to On, completed directory names have a slash appended.
365 mark-modified-lines (Off)
366 If set to On, history lines that have been modified are dis‐
367 played with a preceding asterisk (*).
368 mark-symlinked-directories (Off)
369 If set to On, completed names which are symbolic links to direc‐
370 tories have a slash appended (subject to the value of mark-di‐
371 rectories).
372 match-hidden-files (On)
373 This variable, when set to On, causes readline to match files
374 whose names begin with a `.' (hidden files) when performing
375 filename completion. If set to Off, the leading `.' must be
376 supplied by the user in the filename to be completed.
377 menu-complete-display-prefix (Off)
378 If set to On, menu completion displays the common prefix of the
379 list of possible completions (which may be empty) before cycling
380 through the list.
381 output-meta (Off)
382 If set to On, readline will display characters with the eighth
383 bit set directly rather than as a meta-prefixed escape sequence.
384 The default is Off, but readline will set it to On if the locale
385 contains eight-bit characters. This variable is dependent on
386 the LC_CTYPE locale category, and may change if the locale is
387 changed.
388 page-completions (On)
389 If set to On, readline uses an internal more-like pager to dis‐
390 play a screenful of possible completions at a time.
391 print-completions-horizontally (Off)
392 If set to On, readline will display completions with matches
393 sorted horizontally in alphabetical order, rather than down the
394 screen.
395 revert-all-at-newline (Off)
396 If set to On, readline will undo all changes to history lines
397 before returning when accept-line is executed. By default, his‐
398 tory lines may be modified and retain individual undo lists
399 across calls to readline.
400 show-all-if-ambiguous (Off)
401 This alters the default behavior of the completion functions.
402 If set to On, words which have more than one possible completion
403 cause the matches to be listed immediately instead of ringing
404 the bell.
405 show-all-if-unmodified (Off)
406 This alters the default behavior of the completion functions in
407 a fashion similar to show-all-if-ambiguous. If set to On, words
408 which have more than one possible completion without any possi‐
409 ble partial completion (the possible completions don't share a
410 common prefix) cause the matches to be listed immediately in‐
411 stead of ringing the bell.
412 show-mode-in-prompt (Off)
413 If set to On, add a string to the beginning of the prompt indi‐
414 cating the editing mode: emacs, vi command, or vi insertion.
415 The mode strings are user-settable (e.g., emacs-mode-string).
416 skip-completed-text (Off)
417 If set to On, this alters the default completion behavior when
418 inserting a single match into the line. It's only active when
419 performing completion in the middle of a word. If enabled,
420 readline does not insert characters from the completion that
421 match characters after point in the word being completed, so
422 portions of the word following the cursor are not duplicated.
423 vi-cmd-mode-string ((cmd))
424 If the show-mode-in-prompt variable is enabled, this string is
425 displayed immediately before the last line of the primary prompt
426 when vi editing mode is active and in command mode. The value
427 is expanded like a key binding, so the standard set of meta- and
428 control prefixes and backslash escape sequences is available.
429 Use the \1 and \2 escapes to begin and end sequences of non-
430 printing characters, which can be used to embed a terminal con‐
431 trol sequence into the mode string.
432 vi-ins-mode-string ((ins))
433 If the show-mode-in-prompt variable is enabled, this string is
434 displayed immediately before the last line of the primary prompt
435 when vi editing mode is active and in insertion mode. The value
436 is expanded like a key binding, so the standard set of meta- and
437 control prefixes and backslash escape sequences is available.
438 Use the \1 and \2 escapes to begin and end sequences of non-
439 printing characters, which can be used to embed a terminal con‐
440 trol sequence into the mode string.
441 visible-stats (Off)
442 If set to On, a character denoting a file's type as reported by
443 stat(2) is appended to the filename when listing possible com‐
444 pletions.
445
446 Conditional Constructs
447 Readline implements a facility similar in spirit to the conditional
448 compilation features of the C preprocessor which allows key bindings
449 and variable settings to be performed as the result of tests. There
450 are four parser directives used.
451
452 $if The $if construct allows bindings to be made based on the edit‐
453 ing mode, the terminal being used, or the application using
454 readline. The text of the test, after any comparison operator,
455 extends to the end of the line; unless otherwise noted, no char‐
456 acters are required to isolate it.
457
458 mode The mode= form of the $if directive is used to test
459 whether readline is in emacs or vi mode. This may be
460 used in conjunction with the set keymap command, for in‐
461 stance, to set bindings in the emacs-standard and emacs-
462 ctlx keymaps only if readline is starting out in emacs
463 mode.
464
465 term The term= form may be used to include terminal-specific
466 key bindings, perhaps to bind the key sequences output by
467 the terminal's function keys. The word on the right side
468 of the = is tested against the full name of the terminal
469 and the portion of the terminal name before the first -.
470 This allows sun to match both sun and sun-cmd, for in‐
471 stance.
472
473 version
474 The version test may be used to perform comparisons
475 against specific readline versions. The version expands
476 to the current readline version. The set of comparison
477 operators includes =, (and ==), !=, <=, >=, <, and >.
478 The version number supplied on the right side of the op‐
479 erator consists of a major version number, an optional
480 decimal point, and an optional minor version (e.g., 7.1).
481 If the minor version is omitted, it is assumed to be 0.
482 The operator may be separated from the string version and
483 from the version number argument by whitespace.
484
485 application
486 The application construct is used to include application-
487 specific settings. Each program using the readline li‐
488 brary sets the application name, and an initialization
489 file can test for a particular value. This could be used
490 to bind key sequences to functions useful for a specific
491 program. For instance, the following command adds a key
492 sequence that quotes the current or previous word in
493 bash:
494
495 $if Bash
496 # Quote the current or previous word
497 "\C-xq": "\eb\"\ef\""
498 $endif
499
500 variable
501 The variable construct provides simple equality tests for
502 readline variables and values. The permitted comparison
503 operators are =, ==, and !=. The variable name must be
504 separated from the comparison operator by whitespace; the
505 operator may be separated from the value on the right
506 hand side by whitespace. Both string and boolean vari‐
507 ables may be tested. Boolean variables must be tested
508 against the values on and off.
509
510 $endif This command, as seen in the previous example, terminates an $if
511 command.
512
513 $else Commands in this branch of the $if directive are executed if the
514 test fails.
515
516 $include
517 This directive takes a single filename as an argument and reads
518 commands and bindings from that file. For example, the follow‐
519 ing directive would read /etc/inputrc:
520
521 $include /etc/inputrc
522
524 Readline provides commands for searching through the command history
525 for lines containing a specified string. There are two search modes:
526 incremental and non-incremental.
527
528 Incremental searches begin before the user has finished typing the
529 search string. As each character of the search string is typed, read‐
530 line displays the next entry from the history matching the string typed
531 so far. An incremental search requires only as many characters as
532 needed to find the desired history entry. To search backward in the
533 history for a particular string, type C-r. Typing C-s searches forward
534 through the history. The characters present in the value of the
535 isearch-terminators variable are used to terminate an incremental
536 search. If that variable has not been assigned a value the Escape and
537 C-J characters will terminate an incremental search. C-G will abort an
538 incremental search and restore the original line. When the search is
539 terminated, the history entry containing the search string becomes the
540 current line.
541
542 To find other matching entries in the history list, type C-s or C-r as
543 appropriate. This will search backward or forward in the history for
544 the next line matching the search string typed so far. Any other key
545 sequence bound to a readline command will terminate the search and exe‐
546 cute that command. For instance, a newline will terminate the search
547 and accept the line, thereby executing the command from the history
548 list. A movement command will terminate the search, make the last line
549 found the current line, and begin editing.
550
551 Non-incremental searches read the entire search string before starting
552 to search for matching history lines. The search string may be typed
553 by the user or be part of the contents of the current line.
554
556 The following is a list of the names of the commands and the default
557 key sequences to which they are bound. Command names without an accom‐
558 panying key sequence are unbound by default.
559
560 In the following descriptions, point refers to the current cursor posi‐
561 tion, and mark refers to a cursor position saved by the set-mark com‐
562 mand. The text between the point and mark is referred to as the re‐
563 gion.
564
565 Commands for Moving
566 beginning-of-line (C-a)
567 Move to the start of the current line.
568 end-of-line (C-e)
569 Move to the end of the line.
570 forward-char (C-f)
571 Move forward a character.
572 backward-char (C-b)
573 Move back a character.
574 forward-word (M-f)
575 Move forward to the end of the next word. Words are composed of
576 alphanumeric characters (letters and digits).
577 backward-word (M-b)
578 Move back to the start of the current or previous word. Words
579 are composed of alphanumeric characters (letters and digits).
580 previous-screen-line
581 Attempt to move point to the same physical screen column on the
582 previous physical screen line. This will not have the desired
583 effect if the current readline line does not take up more than
584 one physical line or if point is not greater than the length of
585 the prompt plus the screen width.
586 next-screen-line
587 Attempt to move point to the same physical screen column on the
588 next physical screen line. This will not have the desired effect
589 if the current readline line does not take up more than one
590 physical line or if the length of the current readline line is
591 not greater than the length of the prompt plus the screen width.
592 clear-display (M-C-l)
593 Clear the screen and, if possible, the terminal's scrollback
594 buffer, then redraw the current line, leaving the current line
595 at the top of the screen.
596 clear-screen (C-l)
597 Clear the screen, then redraw the current line, leaving the cur‐
598 rent line at the top of the screen. With an argument, refresh
599 the current line without clearing the screen.
600 redraw-current-line
601 Refresh the current line.
602
603 Commands for Manipulating the History
604 accept-line (Newline, Return)
605 Accept the line regardless of where the cursor is. If this line
606 is non-empty, it may be added to the history list for future re‐
607 call with add_history(). If the line is a modified history
608 line, the history line is restored to its original state.
609 previous-history (C-p)
610 Fetch the previous command from the history list, moving back in
611 the list.
612 next-history (C-n)
613 Fetch the next command from the history list, moving forward in
614 the list.
615 beginning-of-history (M-<)
616 Move to the first line in the history.
617 end-of-history (M->)
618 Move to the end of the input history, i.e., the line currently
619 being entered.
620 operate-and-get-next (C-o)
621 Accept the current line for return to the calling application as
622 if a newline had been entered, and fetch the next line relative
623 to the current line from the history for editing. A numeric ar‐
624 gument, if supplied, specifies the history entry to use instead
625 of the current line.
626 fetch-history
627 With a numeric argument, fetch that entry from the history list
628 and make it the current line. Without an argument, move back to
629 the first entry in the history list.
630 reverse-search-history (C-r)
631 Search backward starting at the current line and moving `up'
632 through the history as necessary. This is an incremental
633 search.
634 forward-search-history (C-s)
635 Search forward starting at the current line and moving `down'
636 through the history as necessary. This is an incremental
637 search.
638 non-incremental-reverse-search-history (M-p)
639 Search backward through the history starting at the current line
640 using a non-incremental search for a string supplied by the
641 user.
642 non-incremental-forward-search-history (M-n)
643 Search forward through the history using a non-incremental
644 search for a string supplied by the user.
645 history-search-backward
646 Search backward through the history for the string of characters
647 between the start of the current line and the current cursor po‐
648 sition (the point). The search string must match at the begin‐
649 ning of a history line. This is a non-incremental search.
650 history-search-forward
651 Search forward through the history for the string of characters
652 between the start of the current line and the point. The search
653 string must match at the beginning of a history line. This is a
654 non-incremental search.
655 history-substring-search-backward
656 Search backward through the history for the string of characters
657 between the start of the current line and the current cursor po‐
658 sition (the point). The search string may match anywhere in a
659 history line. This is a non-incremental search.
660 history-substring-search-forward
661 Search forward through the history for the string of characters
662 between the start of the current line and the point. The search
663 string may match anywhere in a history line. This is a non-in‐
664 cremental search.
665 yank-nth-arg (M-C-y)
666 Insert the first argument to the previous command (usually the
667 second word on the previous line) at point. With an argument n,
668 insert the nth word from the previous command (the words in the
669 previous command begin with word 0). A negative argument in‐
670 serts the nth word from the end of the previous command. Once
671 the argument n is computed, the argument is extracted as if the
672 "!n" history expansion had been specified.
673 yank-last-arg (M-., M-_)
674 Insert the last argument to the previous command (the last word
675 of the previous history entry). With a numeric argument, behave
676 exactly like yank-nth-arg. Successive calls to yank-last-arg
677 move back through the history list, inserting the last word (or
678 the word specified by the argument to the first call) of each
679 line in turn. Any numeric argument supplied to these successive
680 calls determines the direction to move through the history. A
681 negative argument switches the direction through the history
682 (back or forward). The history expansion facilities are used to
683 extract the last argument, as if the "!$" history expansion had
684 been specified.
685
686 Commands for Changing Text
687 end-of-file (usually C-d)
688 The character indicating end-of-file as set, for example, by
689 ``stty''. If this character is read when there are no charac‐
690 ters on the line, and point is at the beginning of the line,
691 readline interprets it as the end of input and returns EOF.
692 delete-char (C-d)
693 Delete the character at point. If this function is bound to the
694 same character as the tty EOF character, as C-d commonly is, see
695 above for the effects.
696 backward-delete-char (Rubout)
697 Delete the character behind the cursor. When given a numeric
698 argument, save the deleted text on the kill ring.
699 forward-backward-delete-char
700 Delete the character under the cursor, unless the cursor is at
701 the end of the line, in which case the character behind the cur‐
702 sor is deleted.
703 quoted-insert (C-q, C-v)
704 Add the next character that you type to the line verbatim. This
705 is how to insert characters like C-q, for example.
706 tab-insert (M-TAB)
707 Insert a tab character.
708 self-insert (a, b, A, 1, !, ...)
709 Insert the character typed.
710 transpose-chars (C-t)
711 Drag the character before point forward over the character at
712 point, moving point forward as well. If point is at the end of
713 the line, then this transposes the two characters before point.
714 Negative arguments have no effect.
715 transpose-words (M-t)
716 Drag the word before point past the word after point, moving
717 point over that word as well. If point is at the end of the
718 line, this transposes the last two words on the line.
719 upcase-word (M-u)
720 Uppercase the current (or following) word. With a negative ar‐
721 gument, uppercase the previous word, but do not move point.
722 downcase-word (M-l)
723 Lowercase the current (or following) word. With a negative ar‐
724 gument, lowercase the previous word, but do not move point.
725 capitalize-word (M-c)
726 Capitalize the current (or following) word. With a negative ar‐
727 gument, capitalize the previous word, but do not move point.
728 overwrite-mode
729 Toggle overwrite mode. With an explicit positive numeric argu‐
730 ment, switches to overwrite mode. With an explicit non-positive
731 numeric argument, switches to insert mode. This command affects
732 only emacs mode; vi mode does overwrite differently. Each call
733 to readline() starts in insert mode. In overwrite mode, charac‐
734 ters bound to self-insert replace the text at point rather than
735 pushing the text to the right. Characters bound to back‐
736 ward-delete-char replace the character before point with a
737 space. By default, this command is unbound.
738
739 Killing and Yanking
740 kill-line (C-k)
741 Kill the text from point to the end of the line.
742 backward-kill-line (C-x Rubout)
743 Kill backward to the beginning of the line.
744 unix-line-discard (C-u)
745 Kill backward from point to the beginning of the line. The
746 killed text is saved on the kill-ring.
747 kill-whole-line
748 Kill all characters on the current line, no matter where point
749 is.
750 kill-word (M-d)
751 Kill from point the end of the current word, or if between
752 words, to the end of the next word. Word boundaries are the
753 same as those used by forward-word.
754 backward-kill-word (M-Rubout)
755 Kill the word behind point. Word boundaries are the same as
756 those used by backward-word.
757 unix-word-rubout (C-w)
758 Kill the word behind point, using white space as a word bound‐
759 ary. The killed text is saved on the kill-ring.
760 unix-filename-rubout
761 Kill the word behind point, using white space and the slash
762 character as the word boundaries. The killed text is saved on
763 the kill-ring.
764 delete-horizontal-space (M-\)
765 Delete all spaces and tabs around point.
766 kill-region
767 Kill the text between the point and mark (saved cursor posi‐
768 tion). This text is referred to as the region.
769 copy-region-as-kill
770 Copy the text in the region to the kill buffer.
771 copy-backward-word
772 Copy the word before point to the kill buffer. The word bound‐
773 aries are the same as backward-word.
774 copy-forward-word
775 Copy the word following point to the kill buffer. The word
776 boundaries are the same as forward-word.
777 yank (C-y)
778 Yank the top of the kill ring into the buffer at point.
779 yank-pop (M-y)
780 Rotate the kill ring, and yank the new top. Only works follow‐
781 ing yank or yank-pop.
782
783 Numeric Arguments
784 digit-argument (M-0, M-1, ..., M--)
785 Add this digit to the argument already accumulating, or start a
786 new argument. M-- starts a negative argument.
787 universal-argument
788 This is another way to specify an argument. If this command is
789 followed by one or more digits, optionally with a leading minus
790 sign, those digits define the argument. If the command is fol‐
791 lowed by digits, executing universal-argument again ends the nu‐
792 meric argument, but is otherwise ignored. As a special case, if
793 this command is immediately followed by a character that is nei‐
794 ther a digit or minus sign, the argument count for the next com‐
795 mand is multiplied by four. The argument count is initially
796 one, so executing this function the first time makes the argu‐
797 ment count four, a second time makes the argument count sixteen,
798 and so on.
799
800 Completing
801 complete (TAB)
802 Attempt to perform completion on the text before point. The ac‐
803 tual completion performed is application-specific. Bash, for
804 instance, attempts completion treating the text as a variable
805 (if the text begins with $), username (if the text begins with
806 ~), hostname (if the text begins with @), or command (including
807 aliases and functions) in turn. If none of these produces a
808 match, filename completion is attempted. Gdb, on the other
809 hand, allows completion of program functions and variables, and
810 only attempts filename completion under certain circumstances.
811 possible-completions (M-?)
812 List the possible completions of the text before point. When
813 displaying completions, readline sets the number of columns used
814 for display to the value of completion-display-width, the value
815 of the environment variable COLUMNS, or the screen width, in
816 that order.
817 insert-completions (M-*)
818 Insert all completions of the text before point that would have
819 been generated by possible-completions.
820 menu-complete
821 Similar to complete, but replaces the word to be completed with
822 a single match from the list of possible completions. Repeated
823 execution of menu-complete steps through the list of possible
824 completions, inserting each match in turn. At the end of the
825 list of completions, the bell is rung (subject to the setting of
826 bell-style) and the original text is restored. An argument of n
827 moves n positions forward in the list of matches; a negative ar‐
828 gument may be used to move backward through the list. This com‐
829 mand is intended to be bound to TAB, but is unbound by default.
830 menu-complete-backward
831 Identical to menu-complete, but moves backward through the list
832 of possible completions, as if menu-complete had been given a
833 negative argument. This command is unbound by default.
834 delete-char-or-list
835 Deletes the character under the cursor if not at the beginning
836 or end of the line (like delete-char). If at the end of the
837 line, behaves identically to possible-completions.
838
839 Keyboard Macros
840 start-kbd-macro (C-x ()
841 Begin saving the characters typed into the current keyboard
842 macro.
843 end-kbd-macro (C-x ))
844 Stop saving the characters typed into the current keyboard macro
845 and store the definition.
846 call-last-kbd-macro (C-x e)
847 Re-execute the last keyboard macro defined, by making the char‐
848 acters in the macro appear as if typed at the keyboard.
849 print-last-kbd-macro ()
850 Print the last keyboard macro defined in a format suitable for
851 the inputrc file.
852
853 Miscellaneous
854 re-read-init-file (C-x C-r)
855 Read in the contents of the inputrc file, and incorporate any
856 bindings or variable assignments found there.
857 abort (C-g)
858 Abort the current editing command and ring the terminal's bell
859 (subject to the setting of bell-style).
860 do-lowercase-version (M-A, M-B, M-x, ...)
861 If the metafied character x is uppercase, run the command that
862 is bound to the corresponding metafied lowercase character. The
863 behavior is undefined if x is already lowercase.
864 prefix-meta (ESC)
865 Metafy the next character typed. ESC f is equivalent to Meta-f.
866 undo (C-_, C-x C-u)
867 Incremental undo, separately remembered for each line.
868 revert-line (M-r)
869 Undo all changes made to this line. This is like executing the
870 undo command enough times to return the line to its initial
871 state.
872 tilde-expand (M-&)
873 Perform tilde expansion on the current word.
874 set-mark (C-@, M-<space>)
875 Set the mark to the point. If a numeric argument is supplied,
876 the mark is set to that position.
877 exchange-point-and-mark (C-x C-x)
878 Swap the point with the mark. The current cursor position is
879 set to the saved position, and the old cursor position is saved
880 as the mark.
881 character-search (C-])
882 A character is read and point is moved to the next occurrence of
883 that character. A negative argument searches for previous oc‐
884 currences.
885 character-search-backward (M-C-])
886 A character is read and point is moved to the previous occur‐
887 rence of that character. A negative argument searches for sub‐
888 sequent occurrences.
889 skip-csi-sequence
890 Read enough characters to consume a multi-key sequence such as
891 those defined for keys like Home and End. Such sequences begin
892 with a Control Sequence Indicator (CSI), usually ESC-[. If this
893 sequence is bound to "\[", keys producing such sequences will
894 have no effect unless explicitly bound to a readline command,
895 instead of inserting stray characters into the editing buffer.
896 This is unbound by default, but usually bound to ESC-[.
897 insert-comment (M-#)
898 Without a numeric argument, the value of the readline com‐
899 ment-begin variable is inserted at the beginning of the current
900 line. If a numeric argument is supplied, this command acts as a
901 toggle: if the characters at the beginning of the line do not
902 match the value of comment-begin, the value is inserted, other‐
903 wise the characters in comment-begin are deleted from the begin‐
904 ning of the line. In either case, the line is accepted as if a
905 newline had been typed. The default value of comment-begin
906 makes the current line a shell comment. If a numeric argument
907 causes the comment character to be removed, the line will be ex‐
908 ecuted by the shell.
909 dump-functions
910 Print all of the functions and their key bindings to the read‐
911 line output stream. If a numeric argument is supplied, the out‐
912 put is formatted in such a way that it can be made part of an
913 inputrc file.
914 dump-variables
915 Print all of the settable variables and their values to the
916 readline output stream. If a numeric argument is supplied, the
917 output is formatted in such a way that it can be made part of an
918 inputrc file.
919 dump-macros
920 Print all of the readline key sequences bound to macros and the
921 strings they output. If a numeric argument is supplied, the
922 output is formatted in such a way that it can be made part of an
923 inputrc file.
924 emacs-editing-mode (C-e)
925 When in vi command mode, this causes a switch to emacs editing
926 mode.
927 vi-editing-mode (M-C-j)
928 When in emacs editing mode, this causes a switch to vi editing
929 mode.
930
932 The following is a list of the default emacs and vi bindings. Charac‐
933 ters with the eighth bit set are written as M-<character>, and are re‐
934 ferred to as metafied characters. The printable ASCII characters not
935 mentioned in the list of emacs standard bindings are bound to the
936 self-insert function, which just inserts the given character into the
937 input line. In vi insertion mode, all characters not specifically men‐
938 tioned are bound to self-insert. Characters assigned to signal genera‐
939 tion by stty(1) or the terminal driver, such as C-Z or C-C, retain that
940 function. Upper and lower case metafied characters are bound to the
941 same function in the emacs mode meta keymap. The remaining characters
942 are unbound, which causes readline to ring the bell (subject to the
943 setting of the bell-style variable).
944
945 Emacs Mode
946 Emacs Standard bindings
947
948 "C-@" set-mark
949 "C-A" beginning-of-line
950 "C-B" backward-char
951 "C-D" delete-char
952 "C-E" end-of-line
953 "C-F" forward-char
954 "C-G" abort
955 "C-H" backward-delete-char
956 "C-I" complete
957 "C-J" accept-line
958 "C-K" kill-line
959 "C-L" clear-screen
960 "C-M" accept-line
961 "C-N" next-history
962 "C-P" previous-history
963 "C-Q" quoted-insert
964 "C-R" reverse-search-history
965 "C-S" forward-search-history
966 "C-T" transpose-chars
967 "C-U" unix-line-discard
968 "C-V" quoted-insert
969 "C-W" unix-word-rubout
970 "C-Y" yank
971 "C-]" character-search
972 "C-_" undo
973 " " to "/" self-insert
974 "0" to "9" self-insert
975 ":" to "~" self-insert
976 "C-?" backward-delete-char
977
978 Emacs Meta bindings
979
980 "M-C-G" abort
981 "M-C-H" backward-kill-word
982 "M-C-I" tab-insert
983 "M-C-J" vi-editing-mode
984 "M-C-L" clear-display
985 "M-C-M" vi-editing-mode
986 "M-C-R" revert-line
987 "M-C-Y" yank-nth-arg
988 "M-C-[" complete
989 "M-C-]" character-search-backward
990 "M-space" set-mark
991 "M-#" insert-comment
992 "M-&" tilde-expand
993 "M-*" insert-completions
994 "M--" digit-argument
995 "M-." yank-last-arg
996 "M-0" digit-argument
997 "M-1" digit-argument
998 "M-2" digit-argument
999 "M-3" digit-argument
1000 "M-4" digit-argument
1001 "M-5" digit-argument
1002 "M-6" digit-argument
1003 "M-7" digit-argument
1004 "M-8" digit-argument
1005 "M-9" digit-argument
1006 "M-<" beginning-of-history
1007 "M-=" possible-completions
1008 "M->" end-of-history
1009 "M-?" possible-completions
1010 "M-B" backward-word
1011 "M-C" capitalize-word
1012 "M-D" kill-word
1013 "M-F" forward-word
1014 "M-L" downcase-word
1015 "M-N" non-incremental-forward-search-history
1016 "M-P" non-incremental-reverse-search-history
1017 "M-R" revert-line
1018 "M-T" transpose-words
1019 "M-U" upcase-word
1020 "M-Y" yank-pop
1021 "M-\" delete-horizontal-space
1022 "M-~" tilde-expand
1023 "M-C-?" backward-kill-word
1024 "M-_" yank-last-arg
1025
1026 Emacs Control-X bindings
1027
1028 "C-XC-G" abort
1029 "C-XC-R" re-read-init-file
1030 "C-XC-U" undo
1031 "C-XC-X" exchange-point-and-mark
1032 "C-X(" start-kbd-macro
1033 "C-X)" end-kbd-macro
1034 "C-XE" call-last-kbd-macro
1035 "C-XC-?" backward-kill-line
1036
1037
1038 VI Mode bindings
1039 VI Insert Mode functions
1040
1041 "C-D" vi-eof-maybe
1042 "C-H" backward-delete-char
1043 "C-I" complete
1044 "C-J" accept-line
1045 "C-M" accept-line
1046 "C-R" reverse-search-history
1047 "C-S" forward-search-history
1048 "C-T" transpose-chars
1049 "C-U" unix-line-discard
1050 "C-V" quoted-insert
1051 "C-W" unix-word-rubout
1052 "C-Y" yank
1053 "C-[" vi-movement-mode
1054 "C-_" undo
1055 " " to "~" self-insert
1056 "C-?" backward-delete-char
1057
1058 VI Command Mode functions
1059
1060 "C-D" vi-eof-maybe
1061 "C-E" emacs-editing-mode
1062 "C-G" abort
1063 "C-H" backward-char
1064 "C-J" accept-line
1065 "C-K" kill-line
1066 "C-L" clear-screen
1067 "C-M" accept-line
1068 "C-N" next-history
1069 "C-P" previous-history
1070 "C-Q" quoted-insert
1071 "C-R" reverse-search-history
1072 "C-S" forward-search-history
1073 "C-T" transpose-chars
1074 "C-U" unix-line-discard
1075 "C-V" quoted-insert
1076 "C-W" unix-word-rubout
1077 "C-Y" yank
1078 "C-_" vi-undo
1079 " " forward-char
1080 "#" insert-comment
1081 "$" end-of-line
1082 "%" vi-match
1083 "&" vi-tilde-expand
1084 "*" vi-complete
1085 "+" next-history
1086 "," vi-char-search
1087 "-" previous-history
1088 "." vi-redo
1089 "/" vi-search
1090 "0" beginning-of-line
1091 "1" to "9" vi-arg-digit
1092 ";" vi-char-search
1093 "=" vi-complete
1094 "?" vi-search
1095 "A" vi-append-eol
1096 "B" vi-prev-word
1097 "C" vi-change-to
1098 "D" vi-delete-to
1099 "E" vi-end-word
1100 "F" vi-char-search
1101 "G" vi-fetch-history
1102 "I" vi-insert-beg
1103 "N" vi-search-again
1104 "P" vi-put
1105 "R" vi-replace
1106 "S" vi-subst
1107 "T" vi-char-search
1108 "U" revert-line
1109 "W" vi-next-word
1110 "X" backward-delete-char
1111 "Y" vi-yank-to
1112 "\" vi-complete
1113 "^" vi-first-print
1114 "_" vi-yank-arg
1115 "`" vi-goto-mark
1116 "a" vi-append-mode
1117 "b" vi-prev-word
1118 "c" vi-change-to
1119 "d" vi-delete-to
1120 "e" vi-end-word
1121 "f" vi-char-search
1122 "h" backward-char
1123 "i" vi-insertion-mode
1124 "j" next-history
1125 "k" prev-history
1126 "l" forward-char
1127 "m" vi-set-mark
1128 "n" vi-search-again
1129 "p" vi-put
1130 "r" vi-change-char
1131 "s" vi-subst
1132 "t" vi-char-search
1133 "u" vi-undo
1134 "w" vi-next-word
1135 "x" vi-delete
1136 "y" vi-yank-to
1137 "|" vi-column
1138 "~" vi-change-case
1139
1141 The Gnu Readline Library, Brian Fox and Chet Ramey
1142 The Gnu History Library, Brian Fox and Chet Ramey
1143 bash(1)
1144
1146 ~/.inputrc
1147 Individual readline initialization file
1148
1150 Brian Fox, Free Software Foundation
1151 bfox@gnu.org
1152
1153 Chet Ramey, Case Western Reserve University
1154 chet.ramey@case.edu
1155
1157 If you find a bug in readline, you should report it. But first, you
1158 should make sure that it really is a bug, and that it appears in the
1159 latest version of the readline library that you have.
1160
1161 Once you have determined that a bug actually exists, mail a bug report
1162 to bug-readline@gnu.org. If you have a fix, you are welcome to mail
1163 that as well! Suggestions and `philosophical' bug reports may be
1164 mailed to bug-readline@gnu.org or posted to the Usenet newsgroup
1165 gnu.bash.bug.
1166
1167 Comments and bug reports concerning this manual page should be directed
1168 to chet.ramey@case.edu.
1169
1171 It's too big and too slow.
1172
1173
1174
1175GNU Readline 8.2 2022 September 19 READLINE(3)