1 @comment %**start of header (This is for running Texinfo on a region.)
2 @setfilename rluser.info
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6 This file documents the end user interface to the GNU command line
7 editing features. It is to be an appendix to manuals for programs which
8 use these features. There is a document entitled "readline.texinfo"
9 which contains both end-user and programmer documentation for the
12 Copyright (C) 1988--2014 Free Software Foundation, Inc.
14 Authored by Brian Fox and Chet Ramey.
16 Permission is granted to process this file through Tex and print the
17 results, provided the printed document carries copying permission notice
18 identical to this one except for the removal of this paragraph (this
19 paragraph not being relevant to the printed manual).
21 Permission is granted to make and distribute verbatim copies of this manual
22 provided the copyright notice and this permission notice are preserved on
25 Permission is granted to copy and distribute modified versions of this
26 manual under the conditions for verbatim copying, provided also that the
27 GNU Copyright statement is available to the distributee, and provided that
28 the entire resulting derived work is distributed under the terms of a
29 permission notice identical to this one.
31 Permission is granted to copy and distribute translations of this manual
32 into another language, under the above conditions for modified versions.
35 @comment If you are including this manual as an appendix, then set the
36 @comment variable readline-appendix.
42 @node Command Line Editing
43 @chapter Command Line Editing
45 This chapter describes the basic features of the @sc{gnu}
46 command line editing interface.
48 Command line editing is provided by the Readline library, which is
49 used by several different programs, including Bash.
50 Command line editing is enabled by default when using an interactive shell,
51 unless the @option{--noediting} option is supplied at shell invocation.
52 Line editing is also used when using the @option{-e} option to the
53 @code{read} builtin command (@pxref{Bash Builtins}).
54 By default, the line editing commands are similar to those of Emacs.
55 A vi-style line editing interface is also available.
56 Line editing can be enabled at any time using the @option{-o emacs} or
57 @option{-o vi} options to the @code{set} builtin command
58 (@pxref{The Set Builtin}), or disabled using the @option{+o emacs} or
59 @option{+o vi} options to @code{set}.
63 * Introduction and Notation:: Notation used in this text.
64 * Readline Interaction:: The minimum set of commands for editing a line.
65 * Readline Init File:: Customizing Readline from a user's view.
66 * Bindable Readline Commands:: A description of most of the Readline commands
68 * Readline vi Mode:: A short description of how to make Readline
69 behave like the vi editor.
71 * Programmable Completion:: How to specify the possible completions for
73 * Programmable Completion Builtins:: Builtin commands to specify how to
74 complete arguments for a particular command.
75 * A Programmable Completion Example:: An example shell function for
76 generating possible completions.
80 @node Introduction and Notation
81 @section Introduction to Line Editing
83 The following paragraphs describe the notation used to represent
86 The text @kbd{C-k} is read as `Control-K' and describes the character
87 produced when the @key{k} key is pressed while the Control key
90 The text @kbd{M-k} is read as `Meta-K' and describes the character
91 produced when the Meta key (if you have one) is depressed, and the @key{k}
93 The Meta key is labeled @key{ALT} on many keyboards.
94 On keyboards with two keys labeled @key{ALT} (usually to either side of
95 the space bar), the @key{ALT} on the left side is generally set to
97 The @key{ALT} key on the right may also be configured to work as a
98 Meta key or may be configured as some other modifier, such as a
99 Compose key for typing accented characters.
101 If you do not have a Meta or @key{ALT} key, or another key working as
102 a Meta key, the identical keystroke can be generated by typing @key{ESC}
103 @emph{first}, and then typing @key{k}.
104 Either process is known as @dfn{metafying} the @key{k} key.
106 The text @kbd{M-C-k} is read as `Meta-Control-k' and describes the
107 character produced by @dfn{metafying} @kbd{C-k}.
109 In addition, several keys have their own names. Specifically,
110 @key{DEL}, @key{ESC}, @key{LFD}, @key{SPC}, @key{RET}, and @key{TAB} all
111 stand for themselves when seen in this text, or in an init file
112 (@pxref{Readline Init File}).
113 If your keyboard lacks a @key{LFD} key, typing @key{C-j} will
114 produce the desired character.
115 The @key{RET} key may be labeled @key{Return} or @key{Enter} on
118 @node Readline Interaction
119 @section Readline Interaction
120 @cindex interaction, readline
122 Often during an interactive session you type in a long line of text,
123 only to notice that the first word on the line is misspelled. The
124 Readline library gives you a set of commands for manipulating the text
125 as you type it in, allowing you to just fix your typo, and not forcing
126 you to retype the majority of the line. Using these editing commands,
127 you move the cursor to the place that needs correction, and delete or
128 insert the text of the corrections. Then, when you are satisfied with
129 the line, you simply press @key{RET}. You do not have to be at the
130 end of the line to press @key{RET}; the entire line is accepted
131 regardless of the location of the cursor within the line.
134 * Readline Bare Essentials:: The least you need to know about Readline.
135 * Readline Movement Commands:: Moving about the input line.
136 * Readline Killing Commands:: How to delete text, and how to get it back!
137 * Readline Arguments:: Giving numeric arguments to commands.
138 * Searching:: Searching through previous lines.
141 @node Readline Bare Essentials
142 @subsection Readline Bare Essentials
143 @cindex notation, readline
144 @cindex command editing
145 @cindex editing command lines
147 In order to enter characters into the line, simply type them. The typed
148 character appears where the cursor was, and then the cursor moves one
149 space to the right. If you mistype a character, you can use your
150 erase character to back up and delete the mistyped character.
152 Sometimes you may mistype a character, and
153 not notice the error until you have typed several other characters. In
154 that case, you can type @kbd{C-b} to move the cursor to the left, and then
155 correct your mistake. Afterwards, you can move the cursor to the right
158 When you add text in the middle of a line, you will notice that characters
159 to the right of the cursor are `pushed over' to make room for the text
160 that you have inserted. Likewise, when you delete text behind the cursor,
161 characters to the right of the cursor are `pulled back' to fill in the
162 blank space created by the removal of the text. A list of the bare
163 essentials for editing the text of an input line follows.
167 Move back one character.
169 Move forward one character.
170 @item @key{DEL} or @key{Backspace}
171 Delete the character to the left of the cursor.
173 Delete the character underneath the cursor.
174 @item @w{Printing characters}
175 Insert the character into the line at the cursor.
176 @item @kbd{C-_} or @kbd{C-x C-u}
177 Undo the last editing command. You can undo all the way back to an
182 (Depending on your configuration, the @key{Backspace} key be set to
183 delete the character to the left of the cursor and the @key{DEL} key set
184 to delete the character underneath the cursor, like @kbd{C-d}, rather
185 than the character to the left of the cursor.)
187 @node Readline Movement Commands
188 @subsection Readline Movement Commands
191 The above table describes the most basic keystrokes that you need
192 in order to do editing of the input line. For your convenience, many
193 other commands have been added in addition to @kbd{C-b}, @kbd{C-f},
194 @kbd{C-d}, and @key{DEL}. Here are some commands for moving more rapidly
199 Move to the start of the line.
201 Move to the end of the line.
203 Move forward a word, where a word is composed of letters and digits.
205 Move backward a word.
207 Clear the screen, reprinting the current line at the top.
210 Notice how @kbd{C-f} moves forward a character, while @kbd{M-f} moves
211 forward a word. It is a loose convention that control keystrokes
212 operate on characters while meta keystrokes operate on words.
214 @node Readline Killing Commands
215 @subsection Readline Killing Commands
220 @dfn{Killing} text means to delete the text from the line, but to save
221 it away for later use, usually by @dfn{yanking} (re-inserting)
222 it back into the line.
223 (`Cut' and `paste' are more recent jargon for `kill' and `yank'.)
225 If the description for a command says that it `kills' text, then you can
226 be sure that you can get the text back in a different (or the same)
229 When you use a kill command, the text is saved in a @dfn{kill-ring}.
230 Any number of consecutive kills save all of the killed text together, so
231 that when you yank it back, you get it all. The kill
232 ring is not line specific; the text that you killed on a previously
233 typed line is available to be yanked back later, when you are typing
237 Here is the list of commands for killing text.
241 Kill the text from the current cursor position to the end of the line.
244 Kill from the cursor to the end of the current word, or, if between
245 words, to the end of the next word.
246 Word boundaries are the same as those used by @kbd{M-f}.
249 Kill from the cursor the start of the current word, or, if between
250 words, to the start of the previous word.
251 Word boundaries are the same as those used by @kbd{M-b}.
254 Kill from the cursor to the previous whitespace. This is different than
255 @kbd{M-@key{DEL}} because the word boundaries differ.
259 Here is how to @dfn{yank} the text back into the line. Yanking
260 means to copy the most-recently-killed text from the kill buffer.
264 Yank the most recently killed text back into the buffer at the cursor.
267 Rotate the kill-ring, and yank the new top. You can only do this if
268 the prior command is @kbd{C-y} or @kbd{M-y}.
271 @node Readline Arguments
272 @subsection Readline Arguments
274 You can pass numeric arguments to Readline commands. Sometimes the
275 argument acts as a repeat count, other times it is the @i{sign} of the
276 argument that is significant. If you pass a negative argument to a
277 command which normally acts in a forward direction, that command will
278 act in a backward direction. For example, to kill text back to the
279 start of the line, you might type @samp{M-- C-k}.
281 The general way to pass numeric arguments to a command is to type meta
282 digits before the command. If the first `digit' typed is a minus
283 sign (@samp{-}), then the sign of the argument will be negative. Once
284 you have typed one meta digit to get the argument started, you can type
285 the remainder of the digits, and then the command. For example, to give
286 the @kbd{C-d} command an argument of 10, you could type @samp{M-1 0 C-d},
287 which will delete the next ten characters on the input line.
290 @subsection Searching for Commands in the History
292 Readline provides commands for searching through the command history
294 (@pxref{Bash History Facilities})
296 for lines containing a specified string.
297 There are two search modes: @dfn{incremental} and @dfn{non-incremental}.
299 Incremental searches begin before the user has finished typing the
301 As each character of the search string is typed, Readline displays
302 the next entry from the history matching the string typed so far.
303 An incremental search requires only as many characters as needed to
304 find the desired history entry.
305 To search backward in the history for a particular string, type
306 @kbd{C-r}. Typing @kbd{C-s} searches forward through the history.
307 The characters present in the value of the @code{isearch-terminators} variable
308 are used to terminate an incremental search.
309 If that variable has not been assigned a value, the @key{ESC} and
310 @kbd{C-J} characters will terminate an incremental search.
311 @kbd{C-g} will abort an incremental search and restore the original line.
312 When the search is terminated, the history entry containing the
313 search string becomes the current line.
315 To find other matching entries in the history list, type @kbd{C-r} or
316 @kbd{C-s} as appropriate.
317 This will search backward or forward in the history for the next
318 entry matching the search string typed so far.
319 Any other key sequence bound to a Readline command will terminate
320 the search and execute that command.
321 For instance, a @key{RET} will terminate the search and accept
322 the line, thereby executing the command from the history list.
323 A movement command will terminate the search, make the last line found
324 the current line, and begin editing.
326 Readline remembers the last incremental search string. If two
327 @kbd{C-r}s are typed without any intervening characters defining a new
328 search string, any remembered search string is used.
330 Non-incremental searches read the entire search string before starting
331 to search for matching history lines. The search string may be
332 typed by the user or be part of the contents of the current line.
334 @node Readline Init File
335 @section Readline Init File
336 @cindex initialization file, readline
338 Although the Readline library comes with a set of Emacs-like
339 keybindings installed by default, it is possible to use a different set
341 Any user can customize programs that use Readline by putting
342 commands in an @dfn{inputrc} file, conventionally in his home directory.
345 file is taken from the value of the shell variable @env{INPUTRC}. If
347 @ifclear BashFeatures
348 file is taken from the value of the environment variable @env{INPUTRC}. If
350 that variable is unset, the default is @file{~/.inputrc}. If that
351 file does not exist or cannot be read, the ultimate default is
354 When a program which uses the Readline library starts up, the
355 init file is read, and the key bindings are set.
357 In addition, the @code{C-x C-r} command re-reads this init file, thus
358 incorporating any changes that you might have made to it.
361 * Readline Init File Syntax:: Syntax for the commands in the inputrc file.
363 * Conditional Init Constructs:: Conditional key bindings in the inputrc file.
365 * Sample Init File:: An example inputrc file.
368 @node Readline Init File Syntax
369 @subsection Readline Init File Syntax
371 There are only a few basic constructs allowed in the
372 Readline init file. Blank lines are ignored.
373 Lines beginning with a @samp{#} are comments.
374 Lines beginning with a @samp{$} indicate conditional
375 constructs (@pxref{Conditional Init Constructs}). Other lines
376 denote variable settings and key bindings.
379 @item Variable Settings
380 You can modify the run-time behavior of Readline by
381 altering the values of variables in Readline
382 using the @code{set} command within the init file.
383 The syntax is simple:
386 set @var{variable} @var{value}
390 Here, for example, is how to
391 change from the default Emacs-like key binding to use
392 @code{vi} line editing commands:
398 Variable names and values, where appropriate, are recognized without regard
399 to case. Unrecognized variable names are ignored.
401 Boolean variables (those that can be set to on or off) are set to on if
402 the value is null or empty, @var{on} (case-insensitive), or 1. Any other
403 value results in the variable being set to off.
406 The @w{@code{bind -V}} command lists the current Readline variable names
407 and values. @xref{Bash Builtins}.
410 A great deal of run-time behavior is changeable with the following
413 @cindex variables, readline
418 Controls what happens when Readline wants to ring the terminal bell.
419 If set to @samp{none}, Readline never rings the bell. If set to
420 @samp{visible}, Readline uses a visible bell if one is available.
421 If set to @samp{audible} (the default), Readline attempts to ring
424 @item bind-tty-special-chars
425 @vindex bind-tty-special-chars
426 If set to @samp{on}, Readline attempts to bind the control characters
427 treated specially by the kernel's terminal driver to their Readline
431 @vindex colored-stats
432 If set to @samp{on}, Readline displays possible completions using different
433 colors to indicate their file type.
434 The color definitions are taken from the value of the @env{LS_COLORS}
435 environment variable.
436 The default is @samp{off}.
439 @vindex comment-begin
440 The string to insert at the beginning of the line when the
441 @code{insert-comment} command is executed. The default value
444 @item completion-display-width
445 @vindex completion-display-width
446 The number of screen columns used to display possible matches
447 when performing completion.
448 The value is ignored if it is less than 0 or greater than the terminal
450 A value of 0 will cause matches to be displayed one per line.
451 The default value is -1.
453 @item completion-ignore-case
454 @vindex completion-ignore-case
455 If set to @samp{on}, Readline performs filename matching and completion
456 in a case-insensitive fashion.
457 The default value is @samp{off}.
459 @item completion-map-case
460 @vindex completion-map-case
461 If set to @samp{on}, and @var{completion-ignore-case} is enabled, Readline
462 treats hyphens (@samp{-}) and underscores (@samp{_}) as equivalent when
463 performing case-insensitive filename matching and completion.
465 @item completion-prefix-display-length
466 @vindex completion-prefix-display-length
467 The length in characters of the common prefix of a list of possible
468 completions that is displayed without modification. When set to a
469 value greater than zero, common prefixes longer than this value are
470 replaced with an ellipsis when displaying possible completions.
472 @item completion-query-items
473 @vindex completion-query-items
474 The number of possible completions that determines when the user is
475 asked whether the list of possibilities should be displayed.
476 If the number of possible completions is greater than this value,
477 Readline will ask the user whether or not he wishes to view
478 them; otherwise, they are simply listed.
479 This variable must be set to an integer value greater than or equal to 0.
480 A negative value means Readline should never ask.
481 The default limit is @code{100}.
485 If set to @samp{on}, Readline will convert characters with the
486 eighth bit set to an @sc{ascii} key sequence by stripping the eighth
487 bit and prefixing an @key{ESC} character, converting them to a
488 meta-prefixed key sequence. The default value is @samp{on}.
490 @item disable-completion
491 @vindex disable-completion
492 If set to @samp{On}, Readline will inhibit word completion.
493 Completion characters will be inserted into the line as if they had
494 been mapped to @code{self-insert}. The default is @samp{off}.
498 The @code{editing-mode} variable controls which default set of
499 key bindings is used. By default, Readline starts up in Emacs editing
500 mode, where the keystrokes are most similar to Emacs. This variable can be
501 set to either @samp{emacs} or @samp{vi}.
503 @item echo-control-characters
504 When set to @samp{on}, on operating systems that indicate they support it,
505 readline echoes a character corresponding to a signal generated from the
506 keyboard. The default is @samp{on}.
509 @vindex enable-keypad
510 When set to @samp{on}, Readline will try to enable the application
511 keypad when it is called. Some systems need this to enable the
512 arrow keys. The default is @samp{off}.
514 @item enable-meta-key
515 When set to @samp{on}, Readline will try to enable any meta modifier
516 key the terminal claims to support when it is called. On many terminals,
517 the meta key is used to send eight-bit characters.
518 The default is @samp{on}.
522 If set to @samp{on}, tilde expansion is performed when Readline
523 attempts word completion. The default is @samp{off}.
525 @item history-preserve-point
526 @vindex history-preserve-point
527 If set to @samp{on}, the history code attempts to place the point (the
528 current cursor position) at the
529 same location on each history line retrieved with @code{previous-history}
530 or @code{next-history}. The default is @samp{off}.
534 Set the maximum number of history entries saved in the history list.
535 If set to zero, any existing history entries are deleted and no new entries
537 If set to a value less than zero, the number of history entries is not
539 By default, the number of history entries is not limited.
541 @item horizontal-scroll-mode
542 @vindex horizontal-scroll-mode
543 This variable can be set to either @samp{on} or @samp{off}. Setting it
544 to @samp{on} means that the text of the lines being edited will scroll
545 horizontally on a single screen line when they are longer than the width
546 of the screen, instead of wrapping onto a new screen line. By default,
547 this variable is set to @samp{off}.
552 If set to @samp{on}, Readline will enable eight-bit input (it
553 will not clear the eighth bit in the characters it reads),
554 regardless of what the terminal claims it can support. The
555 default value is @samp{off}. The name @code{meta-flag} is a
556 synonym for this variable.
558 @item isearch-terminators
559 @vindex isearch-terminators
560 The string of characters that should terminate an incremental search without
561 subsequently executing the character as a command (@pxref{Searching}).
562 If this variable has not been given a value, the characters @key{ESC} and
563 @kbd{C-J} will terminate an incremental search.
567 Sets Readline's idea of the current keymap for key binding commands.
568 Acceptable @code{keymap} names are
570 @code{emacs-standard},
575 @code{vi-command}, and
577 @code{vi} is equivalent to @code{vi-command}; @code{emacs} is
578 equivalent to @code{emacs-standard}. The default value is @code{emacs}.
579 The value of the @code{editing-mode} variable also affects the
583 Specifies the duration Readline will wait for a character when reading an
584 ambiguous key sequence (one that can form a complete key sequence using
585 the input read so far, or can take additional input to complete a longer
587 If no input is received within the timeout, Readline will use the shorter
588 but complete key sequence.
589 Readline uses this value to determine whether or not input is
590 available on the current input source (@code{rl_instream} by default).
591 The value is specified in milliseconds, so a value of 1000 means that
592 Readline will wait one second for additional input.
593 If this variable is set to a value less than or equal to zero, or to a
594 non-numeric value, Readline will wait until another key is pressed to
595 decide which key sequence to complete.
596 The default value is @code{500}.
598 @item mark-directories
599 If set to @samp{on}, completed directory names have a slash
600 appended. The default is @samp{on}.
602 @item mark-modified-lines
603 @vindex mark-modified-lines
604 This variable, when set to @samp{on}, causes Readline to display an
605 asterisk (@samp{*}) at the start of history lines which have been modified.
606 This variable is @samp{off} by default.
608 @item mark-symlinked-directories
609 @vindex mark-symlinked-directories
610 If set to @samp{on}, completed names which are symbolic links
611 to directories have a slash appended (subject to the value of
612 @code{mark-directories}).
613 The default is @samp{off}.
615 @item match-hidden-files
616 @vindex match-hidden-files
617 This variable, when set to @samp{on}, causes Readline to match files whose
618 names begin with a @samp{.} (hidden files) when performing filename
620 If set to @samp{off}, the leading @samp{.} must be
621 supplied by the user in the filename to be completed.
622 This variable is @samp{on} by default.
624 @item menu-complete-display-prefix
625 @vindex menu-complete-display-prefix
626 If set to @samp{on}, menu completion displays the common prefix of the
627 list of possible completions (which may be empty) before cycling through
628 the list. The default is @samp{off}.
632 If set to @samp{on}, Readline will display characters with the
633 eighth bit set directly rather than as a meta-prefixed escape
634 sequence. The default is @samp{off}.
636 @item page-completions
637 @vindex page-completions
638 If set to @samp{on}, Readline uses an internal @code{more}-like pager
639 to display a screenful of possible completions at a time.
640 This variable is @samp{on} by default.
642 @item print-completions-horizontally
643 If set to @samp{on}, Readline will display completions with matches
644 sorted horizontally in alphabetical order, rather than down the screen.
645 The default is @samp{off}.
647 @item revert-all-at-newline
648 @vindex revert-all-at-newline
649 If set to @samp{on}, Readline will undo all changes to history lines
650 before returning when @code{accept-line} is executed. By default,
651 history lines may be modified and retain individual undo lists across
652 calls to @code{readline}. The default is @samp{off}.
654 @item show-all-if-ambiguous
655 @vindex show-all-if-ambiguous
656 This alters the default behavior of the completion functions. If
658 words which have more than one possible completion cause the
659 matches to be listed immediately instead of ringing the bell.
660 The default value is @samp{off}.
662 @item show-all-if-unmodified
663 @vindex show-all-if-unmodified
664 This alters the default behavior of the completion functions in
665 a fashion similar to @var{show-all-if-ambiguous}.
667 words which have more than one possible completion without any
668 possible partial completion (the possible completions don't share
669 a common prefix) cause the matches to be listed immediately instead
671 The default value is @samp{off}.
673 @item show-mode-in-prompt
674 @vindex show-mode-in-prompt
675 If set to @samp{on}, add a character to the beginning of the prompt
676 indicating the editing mode: emacs (@samp{@@}), vi command (@samp{:}),
677 or vi insertion (@samp{+}).
678 The default value is @samp{off}.
680 @item skip-completed-text
681 @vindex skip-completed-text
682 If set to @samp{on}, this alters the default completion behavior when
683 inserting a single match into the line. It's only active when
684 performing completion in the middle of a word. If enabled, readline
685 does not insert characters from the completion that match characters
686 after point in the word being completed, so portions of the word
687 following the cursor are not duplicated.
688 For instance, if this is enabled, attempting completion when the cursor
689 is after the @samp{e} in @samp{Makefile} will result in @samp{Makefile}
690 rather than @samp{Makefilefile}, assuming there is a single possible
692 The default value is @samp{off}.
695 @vindex visible-stats
696 If set to @samp{on}, a character denoting a file's type
697 is appended to the filename when listing possible
698 completions. The default is @samp{off}.
703 The syntax for controlling key bindings in the init file is
704 simple. First you need to find the name of the command that you
705 want to change. The following sections contain tables of the command
706 name, the default keybinding, if any, and a short description of what
709 Once you know the name of the command, simply place on a line
710 in the init file the name of the key
711 you wish to bind the command to, a colon, and then the name of the
713 There can be no space between the key name and the colon -- that will be
714 interpreted as part of the key name.
715 The name of the key can be expressed in different ways, depending on
716 what you find most comfortable.
718 In addition to command names, readline allows keys to be bound
719 to a string that is inserted when the key is pressed (a @var{macro}).
722 The @w{@code{bind -p}} command displays Readline function names and
723 bindings in a format that can put directly into an initialization file.
724 @xref{Bash Builtins}.
728 @item @w{@var{keyname}: @var{function-name} or @var{macro}}
729 @var{keyname} is the name of a key spelled out in English. For example:
731 Control-u: universal-argument
732 Meta-Rubout: backward-kill-word
733 Control-o: "> output"
736 In the above example, @kbd{C-u} is bound to the function
737 @code{universal-argument},
738 @kbd{M-DEL} is bound to the function @code{backward-kill-word}, and
739 @kbd{C-o} is bound to run the macro
740 expressed on the right hand side (that is, to insert the text
741 @samp{> output} into the line).
743 A number of symbolic character names are recognized while
744 processing this key binding syntax:
758 @item @w{"@var{keyseq}": @var{function-name} or @var{macro}}
759 @var{keyseq} differs from @var{keyname} above in that strings
760 denoting an entire key sequence can be specified, by placing
761 the key sequence in double quotes. Some @sc{gnu} Emacs style key
762 escapes can be used, as in the following example, but the
763 special character names are not recognized.
766 "\C-u": universal-argument
767 "\C-x\C-r": re-read-init-file
768 "\e[11~": "Function Key 1"
771 In the above example, @kbd{C-u} is again bound to the function
772 @code{universal-argument} (just as it was in the first example),
773 @samp{@kbd{C-x} @kbd{C-r}} is bound to the function @code{re-read-init-file},
774 and @samp{@key{ESC} @key{[} @key{1} @key{1} @key{~}} is bound to insert
775 the text @samp{Function Key 1}.
779 The following @sc{gnu} Emacs style escape sequences are available when
780 specifying key sequences:
792 @key{"}, a double quotation mark
794 @key{'}, a single quote or apostrophe
797 In addition to the @sc{gnu} Emacs style escape sequences, a second
798 set of backslash escapes is available:
818 the eight-bit character whose value is the octal value @var{nnn}
819 (one to three digits)
821 the eight-bit character whose value is the hexadecimal value @var{HH}
822 (one or two hex digits)
825 When entering the text of a macro, single or double quotes must
826 be used to indicate a macro definition.
827 Unquoted text is assumed to be a function name.
828 In the macro body, the backslash escapes described above are expanded.
829 Backslash will quote any other character in the macro text,
830 including @samp{"} and @samp{'}.
831 For example, the following binding will make @samp{@kbd{C-x} \}
832 insert a single @samp{\} into the line:
839 @node Conditional Init Constructs
840 @subsection Conditional Init Constructs
842 Readline implements a facility similar in spirit to the conditional
843 compilation features of the C preprocessor which allows key
844 bindings and variable settings to be performed as the result
845 of tests. There are four parser directives used.
849 The @code{$if} construct allows bindings to be made based on the
850 editing mode, the terminal being used, or the application using
851 Readline. The text of the test extends to the end of the line;
852 no characters are required to isolate it.
856 The @code{mode=} form of the @code{$if} directive is used to test
857 whether Readline is in @code{emacs} or @code{vi} mode.
858 This may be used in conjunction
859 with the @samp{set keymap} command, for instance, to set bindings in
860 the @code{emacs-standard} and @code{emacs-ctlx} keymaps only if
861 Readline is starting out in @code{emacs} mode.
864 The @code{term=} form may be used to include terminal-specific
865 key bindings, perhaps to bind the key sequences output by the
866 terminal's function keys. The word on the right side of the
867 @samp{=} is tested against both the full name of the terminal and
868 the portion of the terminal name before the first @samp{-}. This
869 allows @code{sun} to match both @code{sun} and @code{sun-cmd},
873 The @var{application} construct is used to include
874 application-specific settings. Each program using the Readline
875 library sets the @var{application name}, and you can test for
877 This could be used to bind key sequences to functions useful for
878 a specific program. For instance, the following command adds a
879 key sequence that quotes the current or previous word in Bash:
882 # Quote the current or previous word
883 "\C-xq": "\eb\"\ef\""
889 This command, as seen in the previous example, terminates an
893 Commands in this branch of the @code{$if} directive are executed if
897 This directive takes a single filename as an argument and reads commands
898 and bindings from that file.
899 For example, the following directive reads from @file{/etc/inputrc}:
901 $include /etc/inputrc
905 @node Sample Init File
906 @subsection Sample Init File
908 Here is an example of an @var{inputrc} file. This illustrates key
909 binding, variable assignment, and conditional syntax.
913 # This file controls the behaviour of line input editing for
914 # programs that use the GNU Readline library. Existing
915 # programs include FTP, Bash, and GDB.
917 # You can re-read the inputrc file with C-x C-r.
918 # Lines beginning with '#' are comments.
920 # First, include any system-wide bindings and variable
921 # assignments from /etc/Inputrc
922 $include /etc/Inputrc
925 # Set various bindings for emacs mode.
927 set editing-mode emacs
931 Meta-Control-h: backward-kill-word Text after the function name is ignored
934 # Arrow keys in keypad mode
936 #"\M-OD": backward-char
937 #"\M-OC": forward-char
938 #"\M-OA": previous-history
939 #"\M-OB": next-history
941 # Arrow keys in ANSI mode
943 "\M-[D": backward-char
944 "\M-[C": forward-char
945 "\M-[A": previous-history
946 "\M-[B": next-history
948 # Arrow keys in 8 bit keypad mode
950 #"\M-\C-OD": backward-char
951 #"\M-\C-OC": forward-char
952 #"\M-\C-OA": previous-history
953 #"\M-\C-OB": next-history
955 # Arrow keys in 8 bit ANSI mode
957 #"\M-\C-[D": backward-char
958 #"\M-\C-[C": forward-char
959 #"\M-\C-[A": previous-history
960 #"\M-\C-[B": next-history
966 # An old-style binding. This happens to be the default.
969 # Macros that are convenient for shell interaction
972 "\C-xp": "PATH=$@{PATH@}\e\C-e\C-a\ef\C-f"
973 # prepare to type a quoted word --
974 # insert open and close double quotes
975 # and move to just after the open quote
977 # insert a backslash (testing backslash escapes
978 # in sequences and macros)
980 # Quote the current or previous word
981 "\C-xq": "\eb\"\ef\""
982 # Add a binding to refresh the line, which is unbound
983 "\C-xr": redraw-current-line
984 # Edit variable on current line.
985 "\M-\C-v": "\C-a\C-k$\C-y\M-\C-e\C-a\C-y="
988 # use a visible bell if one is available
989 set bell-style visible
991 # don't strip characters to 7 bits when reading
994 # allow iso-latin1 characters to be inserted rather
995 # than converted to prefix-meta sequences
998 # display characters with the eighth bit set directly
999 # rather than as meta-prefixed characters
1002 # if there are more than 150 possible completions for
1003 # a word, ask the user if he wants to see all of them
1004 set completion-query-items 150
1010 "\M-.": yank-last-arg
1014 @node Bindable Readline Commands
1015 @section Bindable Readline Commands
1018 * Commands For Moving:: Moving about the line.
1019 * Commands For History:: Getting at previous lines.
1020 * Commands For Text:: Commands for changing text.
1021 * Commands For Killing:: Commands for killing and yanking.
1022 * Numeric Arguments:: Specifying numeric arguments, repeat counts.
1023 * Commands For Completion:: Getting Readline to do the typing for you.
1024 * Keyboard Macros:: Saving and re-executing typed characters
1025 * Miscellaneous Commands:: Other miscellaneous commands.
1028 This section describes Readline commands that may be bound to key
1031 You can list your key bindings by executing
1032 @w{@code{bind -P}} or, for a more terse format, suitable for an
1033 @var{inputrc} file, @w{@code{bind -p}}. (@xref{Bash Builtins}.)
1035 Command names without an accompanying key sequence are unbound by default.
1037 In the following descriptions, @dfn{point} refers to the current cursor
1038 position, and @dfn{mark} refers to a cursor position saved by the
1039 @code{set-mark} command.
1040 The text between the point and mark is referred to as the @dfn{region}.
1042 @node Commands For Moving
1043 @subsection Commands For Moving
1045 @item beginning-of-line (C-a)
1046 Move to the start of the current line.
1048 @item end-of-line (C-e)
1049 Move to the end of the line.
1051 @item forward-char (C-f)
1052 Move forward a character.
1054 @item backward-char (C-b)
1055 Move back a character.
1057 @item forward-word (M-f)
1058 Move forward to the end of the next word.
1059 Words are composed of letters and digits.
1061 @item backward-word (M-b)
1062 Move back to the start of the current or previous word.
1063 Words are composed of letters and digits.
1066 @item shell-forward-word ()
1067 Move forward to the end of the next word.
1068 Words are delimited by non-quoted shell metacharacters.
1070 @item shell-backward-word ()
1071 Move back to the start of the current or previous word.
1072 Words are delimited by non-quoted shell metacharacters.
1075 @item clear-screen (C-l)
1076 Clear the screen and redraw the current line,
1077 leaving the current line at the top of the screen.
1079 @item redraw-current-line ()
1080 Refresh the current line. By default, this is unbound.
1084 @node Commands For History
1085 @subsection Commands For Manipulating The History
1088 @item accept-line (Newline or Return)
1090 Accept the line regardless of where the cursor is.
1092 non-empty, add it to the history list according to the setting of
1093 the @env{HISTCONTROL} and @env{HISTIGNORE} variables.
1094 If this line is a modified history line, then restore the history line
1095 to its original state.
1097 @ifclear BashFeatures
1098 Accept the line regardless of where the cursor is.
1100 non-empty, it may be added to the history list for future recall with
1101 @code{add_history()}.
1102 If this line is a modified history line, the history line is restored
1103 to its original state.
1106 @item previous-history (C-p)
1107 Move `back' through the history list, fetching the previous command.
1109 @item next-history (C-n)
1110 Move `forward' through the history list, fetching the next command.
1112 @item beginning-of-history (M-<)
1113 Move to the first line in the history.
1115 @item end-of-history (M->)
1116 Move to the end of the input history, i.e., the line currently
1119 @item reverse-search-history (C-r)
1120 Search backward starting at the current line and moving `up' through
1121 the history as necessary. This is an incremental search.
1123 @item forward-search-history (C-s)
1124 Search forward starting at the current line and moving `down' through
1125 the the history as necessary. This is an incremental search.
1127 @item non-incremental-reverse-search-history (M-p)
1128 Search backward starting at the current line and moving `up'
1129 through the history as necessary using a non-incremental search
1130 for a string supplied by the user.
1132 @item non-incremental-forward-search-history (M-n)
1133 Search forward starting at the current line and moving `down'
1134 through the the history as necessary using a non-incremental search
1135 for a string supplied by the user.
1137 @item history-search-forward ()
1138 Search forward through the history for the string of characters
1139 between the start of the current line and the point.
1140 The search string must match at the beginning of a history line.
1141 This is a non-incremental search.
1142 By default, this command is unbound.
1144 @item history-search-backward ()
1145 Search backward through the history for the string of characters
1146 between the start of the current line and the point.
1147 The search string must match at the beginning of a history line.
1148 This is a non-incremental search.
1149 By default, this command is unbound.
1151 @item history-substr-search-forward ()
1152 Search forward through the history for the string of characters
1153 between the start of the current line and the point.
1154 The search string may match anywhere in a history line.
1155 This is a non-incremental search.
1156 By default, this command is unbound.
1158 @item history-substr-search-backward ()
1159 Search backward through the history for the string of characters
1160 between the start of the current line and the point.
1161 The search string may match anywhere in a history line.
1162 This is a non-incremental search.
1163 By default, this command is unbound.
1165 @item yank-nth-arg (M-C-y)
1166 Insert the first argument to the previous command (usually
1167 the second word on the previous line) at point.
1168 With an argument @var{n},
1169 insert the @var{n}th word from the previous command (the words
1170 in the previous command begin with word 0). A negative argument
1171 inserts the @var{n}th word from the end of the previous command.
1172 Once the argument @var{n} is computed, the argument is extracted
1173 as if the @samp{!@var{n}} history expansion had been specified.
1175 @item yank-last-arg (M-. or M-_)
1176 Insert last argument to the previous command (the last word of the
1177 previous history entry).
1178 With a numeric argument, behave exactly like @code{yank-nth-arg}.
1179 Successive calls to @code{yank-last-arg} move back through the history
1180 list, inserting the last word (or the word specified by the argument to
1181 the first call) of each line in turn.
1182 Any numeric argument supplied to these successive calls determines
1183 the direction to move through the history. A negative argument switches
1184 the direction through the history (back or forward).
1185 The history expansion facilities are used to extract the last argument,
1186 as if the @samp{!$} history expansion had been specified.
1190 @node Commands For Text
1191 @subsection Commands For Changing Text
1195 @item @i{end-of-file} (usually C-d)
1196 The character indicating end-of-file as set, for example, by
1197 @code{stty}. If this character is read when there are no characters
1198 on the line, and point is at the beginning of the line, Readline
1199 interprets it as the end of input and returns @sc{eof}.
1201 @item delete-char (C-d)
1202 Delete the character at point. If this function is bound to the
1203 same character as the tty @sc{eof} character, as @kbd{C-d}
1204 commonly is, see above for the effects.
1206 @item backward-delete-char (Rubout)
1207 Delete the character behind the cursor. A numeric argument means
1208 to kill the characters instead of deleting them.
1210 @item forward-backward-delete-char ()
1211 Delete the character under the cursor, unless the cursor is at the
1212 end of the line, in which case the character behind the cursor is
1213 deleted. By default, this is not bound to a key.
1215 @item quoted-insert (C-q or C-v)
1216 Add the next character typed to the line verbatim. This is
1217 how to insert key sequences like @kbd{C-q}, for example.
1219 @ifclear BashFeatures
1220 @item tab-insert (M-@key{TAB})
1221 Insert a tab character.
1224 @item self-insert (a, b, A, 1, !, @dots{})
1227 @item transpose-chars (C-t)
1228 Drag the character before the cursor forward over
1229 the character at the cursor, moving the
1230 cursor forward as well. If the insertion point
1231 is at the end of the line, then this
1232 transposes the last two characters of the line.
1233 Negative arguments have no effect.
1235 @item transpose-words (M-t)
1236 Drag the word before point past the word after point,
1237 moving point past that word as well.
1238 If the insertion point is at the end of the line, this transposes
1239 the last two words on the line.
1241 @item upcase-word (M-u)
1242 Uppercase the current (or following) word. With a negative argument,
1243 uppercase the previous word, but do not move the cursor.
1245 @item downcase-word (M-l)
1246 Lowercase the current (or following) word. With a negative argument,
1247 lowercase the previous word, but do not move the cursor.
1249 @item capitalize-word (M-c)
1250 Capitalize the current (or following) word. With a negative argument,
1251 capitalize the previous word, but do not move the cursor.
1253 @item overwrite-mode ()
1254 Toggle overwrite mode. With an explicit positive numeric argument,
1255 switches to overwrite mode. With an explicit non-positive numeric
1256 argument, switches to insert mode. This command affects only
1257 @code{emacs} mode; @code{vi} mode does overwrite differently.
1258 Each call to @code{readline()} starts in insert mode.
1260 In overwrite mode, characters bound to @code{self-insert} replace
1261 the text at point rather than pushing the text to the right.
1262 Characters bound to @code{backward-delete-char} replace the character
1263 before point with a space.
1265 By default, this command is unbound.
1269 @node Commands For Killing
1270 @subsection Killing And Yanking
1274 @item kill-line (C-k)
1275 Kill the text from point to the end of the line.
1277 @item backward-kill-line (C-x Rubout)
1278 Kill backward to the beginning of the line.
1280 @item unix-line-discard (C-u)
1281 Kill backward from the cursor to the beginning of the current line.
1283 @item kill-whole-line ()
1284 Kill all characters on the current line, no matter where point is.
1285 By default, this is unbound.
1287 @item kill-word (M-d)
1288 Kill from point to the end of the current word, or if between
1289 words, to the end of the next word.
1290 Word boundaries are the same as @code{forward-word}.
1292 @item backward-kill-word (M-@key{DEL})
1293 Kill the word behind point.
1294 Word boundaries are the same as @code{backward-word}.
1297 @item shell-kill-word ()
1298 Kill from point to the end of the current word, or if between
1299 words, to the end of the next word.
1300 Word boundaries are the same as @code{shell-forward-word}.
1302 @item shell-backward-kill-word ()
1303 Kill the word behind point.
1304 Word boundaries are the same as @code{shell-backward-word}.
1307 @item unix-word-rubout (C-w)
1308 Kill the word behind point, using white space as a word boundary.
1309 The killed text is saved on the kill-ring.
1311 @item unix-filename-rubout ()
1312 Kill the word behind point, using white space and the slash character
1313 as the word boundaries.
1314 The killed text is saved on the kill-ring.
1316 @item delete-horizontal-space ()
1317 Delete all spaces and tabs around point. By default, this is unbound.
1319 @item kill-region ()
1320 Kill the text in the current region.
1321 By default, this command is unbound.
1323 @item copy-region-as-kill ()
1324 Copy the text in the region to the kill buffer, so it can be yanked
1325 right away. By default, this command is unbound.
1327 @item copy-backward-word ()
1328 Copy the word before point to the kill buffer.
1329 The word boundaries are the same as @code{backward-word}.
1330 By default, this command is unbound.
1332 @item copy-forward-word ()
1333 Copy the word following point to the kill buffer.
1334 The word boundaries are the same as @code{forward-word}.
1335 By default, this command is unbound.
1338 Yank the top of the kill ring into the buffer at point.
1340 @item yank-pop (M-y)
1341 Rotate the kill-ring, and yank the new top. You can only do this if
1342 the prior command is @code{yank} or @code{yank-pop}.
1345 @node Numeric Arguments
1346 @subsection Specifying Numeric Arguments
1349 @item digit-argument (@kbd{M-0}, @kbd{M-1}, @dots{} @kbd{M--})
1350 Add this digit to the argument already accumulating, or start a new
1351 argument. @kbd{M--} starts a negative argument.
1353 @item universal-argument ()
1354 This is another way to specify an argument.
1355 If this command is followed by one or more digits, optionally with a
1356 leading minus sign, those digits define the argument.
1357 If the command is followed by digits, executing @code{universal-argument}
1358 again ends the numeric argument, but is otherwise ignored.
1359 As a special case, if this command is immediately followed by a
1360 character that is neither a digit or minus sign, the argument count
1361 for the next command is multiplied by four.
1362 The argument count is initially one, so executing this function the
1363 first time makes the argument count four, a second time makes the
1364 argument count sixteen, and so on.
1365 By default, this is not bound to a key.
1368 @node Commands For Completion
1369 @subsection Letting Readline Type For You
1372 @item complete (@key{TAB})
1373 Attempt to perform completion on the text before point.
1374 The actual completion performed is application-specific.
1376 Bash attempts completion treating the text as a variable (if the
1377 text begins with @samp{$}), username (if the text begins with
1378 @samp{~}), hostname (if the text begins with @samp{@@}), or
1379 command (including aliases and functions) in turn. If none
1380 of these produces a match, filename completion is attempted.
1382 @ifclear BashFeatures
1383 The default is filename completion.
1386 @item possible-completions (M-?)
1387 List the possible completions of the text before point.
1388 When displaying completions, Readline sets the number of columns used
1389 for display to the value of @code{completion-display-width}, the value of
1390 the environment variable @env{COLUMNS}, or the screen width, in that order.
1392 @item insert-completions (M-*)
1393 Insert all completions of the text before point that would have
1394 been generated by @code{possible-completions}.
1396 @item menu-complete ()
1397 Similar to @code{complete}, but replaces the word to be completed
1398 with a single match from the list of possible completions.
1399 Repeated execution of @code{menu-complete} steps through the list
1400 of possible completions, inserting each match in turn.
1401 At the end of the list of completions, the bell is rung
1402 (subject to the setting of @code{bell-style})
1403 and the original text is restored.
1404 An argument of @var{n} moves @var{n} positions forward in the list
1405 of matches; a negative argument may be used to move backward
1407 This command is intended to be bound to @key{TAB}, but is unbound
1410 @item menu-complete-backward ()
1411 Identical to @code{menu-complete}, but moves backward through the list
1412 of possible completions, as if @code{menu-complete} had been given a
1415 @item delete-char-or-list ()
1416 Deletes the character under the cursor if not at the beginning or
1417 end of the line (like @code{delete-char}).
1418 If at the end of the line, behaves identically to
1419 @code{possible-completions}.
1420 This command is unbound by default.
1423 @item complete-filename (M-/)
1424 Attempt filename completion on the text before point.
1426 @item possible-filename-completions (C-x /)
1427 List the possible completions of the text before point,
1428 treating it as a filename.
1430 @item complete-username (M-~)
1431 Attempt completion on the text before point, treating
1434 @item possible-username-completions (C-x ~)
1435 List the possible completions of the text before point,
1436 treating it as a username.
1438 @item complete-variable (M-$)
1439 Attempt completion on the text before point, treating
1440 it as a shell variable.
1442 @item possible-variable-completions (C-x $)
1443 List the possible completions of the text before point,
1444 treating it as a shell variable.
1446 @item complete-hostname (M-@@)
1447 Attempt completion on the text before point, treating
1450 @item possible-hostname-completions (C-x @@)
1451 List the possible completions of the text before point,
1452 treating it as a hostname.
1454 @item complete-command (M-!)
1455 Attempt completion on the text before point, treating
1456 it as a command name. Command completion attempts to
1457 match the text against aliases, reserved words, shell
1458 functions, shell builtins, and finally executable filenames,
1461 @item possible-command-completions (C-x !)
1462 List the possible completions of the text before point,
1463 treating it as a command name.
1465 @item dynamic-complete-history (M-@key{TAB})
1466 Attempt completion on the text before point, comparing
1467 the text against lines from the history list for possible
1470 @item dabbrev-expand ()
1471 Attempt menu completion on the text before point, comparing
1472 the text against lines from the history list for possible
1475 @item complete-into-braces (M-@{)
1476 Perform filename completion and insert the list of possible completions
1477 enclosed within braces so the list is available to the shell
1478 (@pxref{Brace Expansion}).
1483 @node Keyboard Macros
1484 @subsection Keyboard Macros
1487 @item start-kbd-macro (C-x ()
1488 Begin saving the characters typed into the current keyboard macro.
1490 @item end-kbd-macro (C-x ))
1491 Stop saving the characters typed into the current keyboard macro
1492 and save the definition.
1494 @item call-last-kbd-macro (C-x e)
1495 Re-execute the last keyboard macro defined, by making the characters
1496 in the macro appear as if typed at the keyboard.
1498 @item print-last-kbd-macro ()
1499 Print the last keboard macro defined in a format suitable for the
1504 @node Miscellaneous Commands
1505 @subsection Some Miscellaneous Commands
1508 @item re-read-init-file (C-x C-r)
1509 Read in the contents of the @var{inputrc} file, and incorporate
1510 any bindings or variable assignments found there.
1513 Abort the current editing command and
1514 ring the terminal's bell (subject to the setting of
1517 @item do-uppercase-version (M-a, M-b, M-@var{x}, @dots{})
1518 If the metafied character @var{x} is lowercase, run the command
1519 that is bound to the corresponding uppercase character.
1521 @item prefix-meta (@key{ESC})
1522 Metafy the next character typed. This is for keyboards
1523 without a meta key. Typing @samp{@key{ESC} f} is equivalent to typing
1526 @item undo (C-_ or C-x C-u)
1527 Incremental undo, separately remembered for each line.
1529 @item revert-line (M-r)
1530 Undo all changes made to this line. This is like executing the @code{undo}
1531 command enough times to get back to the beginning.
1534 @item tilde-expand (M-&)
1536 @ifclear BashFeatures
1537 @item tilde-expand (M-~)
1539 Perform tilde expansion on the current word.
1541 @item set-mark (C-@@)
1542 Set the mark to the point. If a
1543 numeric argument is supplied, the mark is set to that position.
1545 @item exchange-point-and-mark (C-x C-x)
1546 Swap the point with the mark. The current cursor position is set to
1547 the saved position, and the old cursor position is saved as the mark.
1549 @item character-search (C-])
1550 A character is read and point is moved to the next occurrence of that
1551 character. A negative count searches for previous occurrences.
1553 @item character-search-backward (M-C-])
1554 A character is read and point is moved to the previous occurrence
1555 of that character. A negative count searches for subsequent
1558 @item skip-csi-sequence ()
1559 Read enough characters to consume a multi-key sequence such as those
1560 defined for keys like Home and End. Such sequences begin with a
1561 Control Sequence Indicator (CSI), usually ESC-[. If this sequence is
1562 bound to "\e[", keys producing such sequences will have no effect
1563 unless explicitly bound to a readline command, instead of inserting
1564 stray characters into the editing buffer. This is unbound by default,
1565 but usually bound to ESC-[.
1567 @item insert-comment (M-#)
1568 Without a numeric argument, the value of the @code{comment-begin}
1569 variable is inserted at the beginning of the current line.
1570 If a numeric argument is supplied, this command acts as a toggle: if
1571 the characters at the beginning of the line do not match the value
1572 of @code{comment-begin}, the value is inserted, otherwise
1573 the characters in @code{comment-begin} are deleted from the beginning of
1575 In either case, the line is accepted as if a newline had been typed.
1577 The default value of @code{comment-begin} causes this command
1578 to make the current line a shell comment.
1579 If a numeric argument causes the comment character to be removed, the line
1580 will be executed by the shell.
1583 @item dump-functions ()
1584 Print all of the functions and their key bindings to the
1585 Readline output stream. If a numeric argument is supplied,
1586 the output is formatted in such a way that it can be made part
1587 of an @var{inputrc} file. This command is unbound by default.
1589 @item dump-variables ()
1590 Print all of the settable variables and their values to the
1591 Readline output stream. If a numeric argument is supplied,
1592 the output is formatted in such a way that it can be made part
1593 of an @var{inputrc} file. This command is unbound by default.
1595 @item dump-macros ()
1596 Print all of the Readline key sequences bound to macros and the
1597 strings they output. If a numeric argument is supplied,
1598 the output is formatted in such a way that it can be made part
1599 of an @var{inputrc} file. This command is unbound by default.
1602 @item glob-complete-word (M-g)
1603 The word before point is treated as a pattern for pathname expansion,
1604 with an asterisk implicitly appended. This pattern is used to
1605 generate a list of matching file names for possible completions.
1607 @item glob-expand-word (C-x *)
1608 The word before point is treated as a pattern for pathname expansion,
1609 and the list of matching file names is inserted, replacing the word.
1610 If a numeric argument is supplied, a @samp{*} is appended before
1613 @item glob-list-expansions (C-x g)
1614 The list of expansions that would have been generated by
1615 @code{glob-expand-word} is displayed, and the line is redrawn.
1616 If a numeric argument is supplied, a @samp{*} is appended before
1619 @item display-shell-version (C-x C-v)
1620 Display version information about the current instance of Bash.
1622 @item shell-expand-line (M-C-e)
1623 Expand the line as the shell does.
1624 This performs alias and history expansion as well as all of the shell
1625 word expansions (@pxref{Shell Expansions}).
1627 @item history-expand-line (M-^)
1628 Perform history expansion on the current line.
1630 @item magic-space ()
1631 Perform history expansion on the current line and insert a space
1632 (@pxref{History Interaction}).
1634 @item alias-expand-line ()
1635 Perform alias expansion on the current line (@pxref{Aliases}).
1637 @item history-and-alias-expand-line ()
1638 Perform history and alias expansion on the current line.
1640 @item insert-last-argument (M-. or M-_)
1641 A synonym for @code{yank-last-arg}.
1643 @item operate-and-get-next (C-o)
1644 Accept the current line for execution and fetch the next line
1645 relative to the current line from the history for editing. Any
1646 argument is ignored.
1648 @item edit-and-execute-command (C-xC-e)
1649 Invoke an editor on the current command line, and execute the result as shell
1651 Bash attempts to invoke
1652 @code{$VISUAL}, @code{$EDITOR}, and @code{emacs}
1653 as the editor, in that order.
1657 @ifclear BashFeatures
1658 @item emacs-editing-mode (C-e)
1659 When in @code{vi} command mode, this causes a switch to @code{emacs}
1662 @item vi-editing-mode (M-C-j)
1663 When in @code{emacs} editing mode, this causes a switch to @code{vi}
1670 @node Readline vi Mode
1671 @section Readline vi Mode
1673 While the Readline library does not have a full set of @code{vi}
1674 editing functions, it does contain enough to allow simple editing
1675 of the line. The Readline @code{vi} mode behaves as specified in
1676 the @sc{posix} standard.
1679 In order to switch interactively between @code{emacs} and @code{vi}
1680 editing modes, use the @samp{set -o emacs} and @samp{set -o vi}
1681 commands (@pxref{The Set Builtin}).
1683 @ifclear BashFeatures
1684 In order to switch interactively between @code{emacs} and @code{vi}
1685 editing modes, use the command @kbd{M-C-j} (bound to emacs-editing-mode
1686 when in @code{vi} mode and to vi-editing-mode in @code{emacs} mode).
1688 The Readline default is @code{emacs} mode.
1690 When you enter a line in @code{vi} mode, you are already placed in
1691 `insertion' mode, as if you had typed an @samp{i}. Pressing @key{ESC}
1692 switches you into `command' mode, where you can edit the text of the
1693 line with the standard @code{vi} movement keys, move to previous
1694 history lines with @samp{k} and subsequent lines with @samp{j}, and
1698 @node Programmable Completion
1699 @section Programmable Completion
1700 @cindex programmable completion
1702 When word completion is attempted for an argument to a command for
1703 which a completion specification (a @var{compspec}) has been defined
1704 using the @code{complete} builtin (@pxref{Programmable Completion Builtins}),
1705 the programmable completion facilities are invoked.
1707 First, the command name is identified.
1708 If a compspec has been defined for that command, the
1709 compspec is used to generate the list of possible completions for the word.
1710 If the command word is the empty string (completion attempted at the
1711 beginning of an empty line), any compspec defined with
1712 the @option{-E} option to @code{complete} is used.
1713 If the command word is a full pathname, a compspec for the full
1714 pathname is searched for first.
1715 If no compspec is found for the full pathname, an attempt is made to
1716 find a compspec for the portion following the final slash.
1717 If those searches do not result in a compspec, any compspec defined with
1718 the @option{-D} option to @code{complete} is used as the default.
1720 Once a compspec has been found, it is used to generate the list of
1722 If a compspec is not found, the default Bash completion
1723 described above (@pxref{Commands For Completion}) is performed.
1725 First, the actions specified by the compspec are used.
1726 Only matches which are prefixed by the word being completed are
1728 When the @option{-f} or @option{-d} option is used for filename or
1729 directory name completion, the shell variable @env{FIGNORE} is
1730 used to filter the matches.
1731 @xref{Bash Variables}, for a description of @env{FIGNORE}.
1733 Any completions specified by a filename expansion pattern to the
1734 @option{-G} option are generated next.
1735 The words generated by the pattern need not match the word being completed.
1736 The @env{GLOBIGNORE} shell variable is not used to filter the matches,
1737 but the @env{FIGNORE} shell variable is used.
1739 Next, the string specified as the argument to the @option{-W} option
1741 The string is first split using the characters in the @env{IFS}
1742 special variable as delimiters.
1743 Shell quoting is honored.
1744 Each word is then expanded using
1745 brace expansion, tilde expansion, parameter and variable expansion,
1746 command substitution, and arithmetic expansion,
1747 as described above (@pxref{Shell Expansions}).
1748 The results are split using the rules described above
1749 (@pxref{Word Splitting}).
1750 The results of the expansion are prefix-matched against the word being
1751 completed, and the matching words become the possible completions.
1753 After these matches have been generated, any shell function or command
1754 specified with the @option{-F} and @option{-C} options is invoked.
1755 When the command or function is invoked, the @env{COMP_LINE},
1756 @env{COMP_POINT}, @env{COMP_KEY}, and @env{COMP_TYPE} variables are
1757 assigned values as described above (@pxref{Bash Variables}).
1758 If a shell function is being invoked, the @env{COMP_WORDS} and
1759 @env{COMP_CWORD} variables are also set.
1760 When the function or command is invoked, the first argument ($1) is the
1761 name of the command whose arguments are being completed, the
1762 second argument ($2) is the word being completed, and the third argument
1763 ($3) is the word preceding the word being completed on the current command
1765 No filtering of the generated completions against the word being completed
1766 is performed; the function or command has complete freedom in generating
1769 Any function specified with @option{-F} is invoked first.
1770 The function may use any of the shell facilities, including the
1771 @code{compgen} and @code{compopt} builtins described below
1772 (@pxref{Programmable Completion Builtins}), to generate the matches.
1773 It must put the possible completions in the @env{COMPREPLY} array
1774 variable, one per array element.
1776 Next, any command specified with the @option{-C} option is invoked
1777 in an environment equivalent to command substitution.
1778 It should print a list of completions, one per line, to
1779 the standard output.
1780 Backslash may be used to escape a newline, if necessary.
1782 After all of the possible completions are generated, any filter
1783 specified with the @option{-X} option is applied to the list.
1784 The filter is a pattern as used for pathname expansion; a @samp{&}
1785 in the pattern is replaced with the text of the word being completed.
1786 A literal @samp{&} may be escaped with a backslash; the backslash
1787 is removed before attempting a match.
1788 Any completion that matches the pattern will be removed from the list.
1789 A leading @samp{!} negates the pattern; in this case any completion
1790 not matching the pattern will be removed.
1792 Finally, any prefix and suffix specified with the @option{-P} and @option{-S}
1793 options are added to each member of the completion list, and the result is
1794 returned to the Readline completion code as the list of possible
1797 If the previously-applied actions do not generate any matches, and the
1798 @option{-o dirnames} option was supplied to @code{complete} when the
1799 compspec was defined, directory name completion is attempted.
1801 If the @option{-o plusdirs} option was supplied to @code{complete} when
1802 the compspec was defined, directory name completion is attempted and any
1803 matches are added to the results of the other actions.
1805 By default, if a compspec is found, whatever it generates is returned to
1806 the completion code as the full set of possible completions.
1807 The default Bash completions are not attempted, and the Readline default
1808 of filename completion is disabled.
1809 If the @option{-o bashdefault} option was supplied to @code{complete} when
1810 the compspec was defined, the default Bash completions are attempted
1811 if the compspec generates no matches.
1812 If the @option{-o default} option was supplied to @code{complete} when the
1813 compspec was defined, Readline's default completion will be performed
1814 if the compspec (and, if attempted, the default Bash completions)
1815 generate no matches.
1817 When a compspec indicates that directory name completion is desired,
1818 the programmable completion functions force Readline to append a slash
1819 to completed names which are symbolic links to directories, subject to
1820 the value of the @var{mark-directories} Readline variable, regardless
1821 of the setting of the @var{mark-symlinked-directories} Readline variable.
1823 There is some support for dynamically modifying completions. This is
1824 most useful when used in combination with a default completion specified
1825 with @option{-D}. It's possible for shell functions executed as completion
1826 handlers to indicate that completion should be retried by returning an
1827 exit status of 124. If a shell function returns 124, and changes
1828 the compspec associated with the command on which completion is being
1829 attempted (supplied as the first argument when the function is executed),
1830 programmable completion restarts from the beginning, with an
1831 attempt to find a new compspec for that command. This allows a set of
1832 completions to be built dynamically as completion is attempted, rather than
1833 being loaded all at once.
1835 For instance, assuming that there is a library of compspecs, each kept in a
1836 file corresponding to the name of the command, the following default
1837 completion function would load completions dynamically:
1840 _completion_loader()
1842 . "/etc/bash_completion.d/$1.sh" >/dev/null 2>&1 && return 124
1844 complete -D -F _completion_loader -o bashdefault -o default
1847 @node Programmable Completion Builtins
1848 @section Programmable Completion Builtins
1849 @cindex completion builtins
1851 Three builtin commands are available to manipulate the programmable completion
1852 facilities: one to specify how the arguments to a particular command are to
1853 be completed, and two to modify the completion as it is happening.
1859 @code{compgen [@var{option}] [@var{word}]}
1862 Generate possible completion matches for @var{word} according to
1863 the @var{option}s, which may be any option accepted by the
1865 builtin with the exception of @option{-p} and @option{-r}, and write
1866 the matches to the standard output.
1867 When using the @option{-F} or @option{-C} options, the various shell variables
1868 set by the programmable completion facilities, while available, will not
1871 The matches will be generated in the same way as if the programmable
1872 completion code had generated them directly from a completion specification
1873 with the same flags.
1874 If @var{word} is specified, only those completions matching @var{word}
1877 The return value is true unless an invalid option is supplied, or no
1878 matches were generated.
1883 @code{complete [-abcdefgjksuv] [-o @var{comp-option}] [-DE] [-A @var{action}] [-G @var{globpat}] [-W @var{wordlist}]
1884 [-F @var{function}] [-C @var{command}] [-X @var{filterpat}]
1885 [-P @var{prefix}] [-S @var{suffix}] @var{name} [@var{name} @dots{}]}
1886 @code{complete -pr [-DE] [@var{name} @dots{}]}
1889 Specify how arguments to each @var{name} should be completed.
1890 If the @option{-p} option is supplied, or if no options are supplied, existing
1891 completion specifications are printed in a way that allows them to be
1893 The @option{-r} option removes a completion specification for
1894 each @var{name}, or, if no @var{name}s are supplied, all
1895 completion specifications.
1896 The @option{-D} option indicates that the remaining options and actions should
1897 apply to the ``default'' command completion; that is, completion attempted
1898 on a command for which no completion has previously been defined.
1899 The @option{-E} option indicates that the remaining options and actions should
1900 apply to ``empty'' command completion; that is, completion attempted on a
1903 The process of applying these completion specifications when word completion
1904 is attempted is described above (@pxref{Programmable Completion}). The
1905 @option{-D} option takes precedence over @option{-E}.
1907 Other options, if specified, have the following meanings.
1908 The arguments to the @option{-G}, @option{-W}, and @option{-X} options
1909 (and, if necessary, the @option{-P} and @option{-S} options)
1910 should be quoted to protect them from expansion before the
1911 @code{complete} builtin is invoked.
1915 @item -o @var{comp-option}
1916 The @var{comp-option} controls several aspects of the compspec's behavior
1917 beyond the simple generation of completions.
1918 @var{comp-option} may be one of:
1923 Perform the rest of the default Bash completions if the compspec
1924 generates no matches.
1927 Use Readline's default filename completion if the compspec generates
1931 Perform directory name completion if the compspec generates no matches.
1934 Tell Readline that the compspec generates filenames, so it can perform any
1935 filename-specific processing (like adding a slash to directory names
1936 quoting special characters, or suppressing trailing spaces).
1937 This option is intended to be used with shell functions specified
1941 Tell Readline not to quote the completed words if they are filenames
1942 (quoting filenames is the default).
1945 Tell Readline not to append a space (the default) to words completed at
1946 the end of the line.
1949 After any matches defined by the compspec are generated,
1950 directory name completion is attempted and any
1951 matches are added to the results of the other actions.
1955 @item -A @var{action}
1956 The @var{action} may be one of the following to generate a list of possible
1961 Alias names. May also be specified as @option{-a}.
1964 Array variable names.
1967 Readline key binding names (@pxref{Bindable Readline Commands}).
1970 Names of shell builtin commands. May also be specified as @option{-b}.
1973 Command names. May also be specified as @option{-c}.
1976 Directory names. May also be specified as @option{-d}.
1979 Names of disabled shell builtins.
1982 Names of enabled shell builtins.
1985 Names of exported shell variables. May also be specified as @option{-e}.
1988 File names. May also be specified as @option{-f}.
1991 Names of shell functions.
1994 Group names. May also be specified as @option{-g}.
1997 Help topics as accepted by the @code{help} builtin (@pxref{Bash Builtins}).
2000 Hostnames, as taken from the file specified by the
2001 @env{HOSTFILE} shell variable (@pxref{Bash Variables}).
2004 Job names, if job control is active. May also be specified as @option{-j}.
2007 Shell reserved words. May also be specified as @option{-k}.
2010 Names of running jobs, if job control is active.
2013 Service names. May also be specified as @option{-s}.
2016 Valid arguments for the @option{-o} option to the @code{set} builtin
2017 (@pxref{The Set Builtin}).
2020 Shell option names as accepted by the @code{shopt} builtin
2021 (@pxref{Bash Builtins}).
2027 Names of stopped jobs, if job control is active.
2030 User names. May also be specified as @option{-u}.
2033 Names of all shell variables. May also be specified as @option{-v}.
2036 @item -C @var{command}
2037 @var{command} is executed in a subshell environment, and its output is
2038 used as the possible completions.
2040 @item -F @var{function}
2041 The shell function @var{function} is executed in the current shell
2043 When it is executed, $1 is the name of the command whose arguments are
2044 being completed, $2 is the word being completed, and $3 is the word
2045 preceding the word being completed, as described above
2046 (@pxref{Programmable Completion}).
2047 When it finishes, the possible completions are retrieved from the value
2048 of the @env{COMPREPLY} array variable.
2050 @item -G @var{globpat}
2051 The filename expansion pattern @var{globpat} is expanded to generate
2052 the possible completions.
2054 @item -P @var{prefix}
2055 @var{prefix} is added at the beginning of each possible completion
2056 after all other options have been applied.
2058 @item -S @var{suffix}
2059 @var{suffix} is appended to each possible completion
2060 after all other options have been applied.
2062 @item -W @var{wordlist}
2063 The @var{wordlist} is split using the characters in the
2064 @env{IFS} special variable as delimiters, and each resultant word
2066 The possible completions are the members of the resultant list which
2067 match the word being completed.
2069 @item -X @var{filterpat}
2070 @var{filterpat} is a pattern as used for filename expansion.
2071 It is applied to the list of possible completions generated by the
2072 preceding options and arguments, and each completion matching
2073 @var{filterpat} is removed from the list.
2074 A leading @samp{!} in @var{filterpat} negates the pattern; in this
2075 case, any completion not matching @var{filterpat} is removed.
2078 The return value is true unless an invalid option is supplied, an option
2079 other than @option{-p} or @option{-r} is supplied without a @var{name}
2080 argument, an attempt is made to remove a completion specification for
2081 a @var{name} for which no specification exists, or
2082 an error occurs adding a completion specification.
2087 @code{compopt} [-o @var{option}] [-DE] [+o @var{option}] [@var{name}]
2089 Modify completion options for each @var{name} according to the
2090 @var{option}s, or for the currently-executing completion if no @var{name}s
2092 If no @var{option}s are given, display the completion options for each
2093 @var{name} or the current completion.
2094 The possible values of @var{option} are those valid for the @code{complete}
2095 builtin described above.
2096 The @option{-D} option indicates that the remaining options should
2097 apply to the ``default'' command completion; that is, completion attempted
2098 on a command for which no completion has previously been defined.
2099 The @option{-E} option indicates that the remaining options should
2100 apply to ``empty'' command completion; that is, completion attempted on a
2103 The @option{-D} option takes precedence over @option{-E}.
2105 The return value is true unless an invalid option is supplied, an attempt
2106 is made to modify the options for a @var{name} for which no completion
2107 specification exists, or an output error occurs.
2111 @node A Programmable Completion Example
2112 @section A Programmable Completion Example
2114 The most common way to obtain additional completion functionality beyond
2115 the default actions @code{complete} and @code{compgen} provide is to use
2116 a shell function and bind it to a particular command using @code{complete -F}.
2118 The following function provides completions for the @code{cd} builtin.
2119 It is a reasonably good example of what shell functions must do when
2120 used for completion. This function uses the word passsed as @code{$2}
2121 to determine the directory name to complete. You can also use the
2122 @code{COMP_WORDS} array variable; the current word is indexed by the
2123 @code{COMP_CWORD} variable.
2125 The function relies on the @code{complete} and @code{compgen} builtins
2126 to do much of the work, adding only the things that the Bash @code{cd}
2127 does beyond accepting basic directory names:
2128 tilde expansion (@pxref{Tilde Expansion}),
2129 searching directories in @var{$CDPATH}, which is described above
2130 (@pxref{Bourne Shell Builtins}),
2131 and basic support for the @code{cdable_vars} shell option
2132 (@pxref{The Shopt Builtin}).
2133 @code{_comp_cd} modifies the value of @var{IFS} so that it contains only
2134 a newline to accommodate file names containing spaces and tabs --
2135 @code{compgen} prints the possible completions it generates one per line.
2137 Possible completions go into the @var{COMPREPLY} array variable, one
2138 completion per array element. The programmable completion system retrieves
2139 the completions from there when the function returns.
2142 # A completion function for the cd builtin
2143 # based on the cd completion function from the bash_completion package
2146 local IFS=$' \t\n' # normalize IFS
2147 local cur _skipdot _cdpath
2150 # Tilde expansion, with side effect of expanding tilde to full pathname
2152 \~*) eval cur="$2" ;;
2156 # no cdpath or absolute pathname -- straight directory completion
2157 if [[ -z "$@{CDPATH:-@}" ]] || [[ "$cur" == @@(./*|../*|/*) ]]; then
2158 # compgen prints paths one per line; could also use while loop
2160 COMPREPLY=( $(compgen -d -- "$cur") )
2162 # CDPATH+directories in the current directory if not in CDPATH
2166 # preprocess CDPATH to convert null directory names to .
2167 _cdpath=$@{CDPATH/#:/.:@}
2168 _cdpath=$@{_cdpath//::/:.:@}
2169 _cdpath=$@{_cdpath/%:/:.@}
2170 for i in $@{_cdpath//:/$'\n'@}; do
2171 if [[ $i -ef . ]]; then _skipdot=true; fi
2172 k="$@{#COMPREPLY[@@]@}"
2173 for j in $( compgen -d -- "$i/$cur" ); do
2174 COMPREPLY[k++]=$@{j#$i/@} # cut off directory
2177 $_skipdot || COMPREPLY+=( $(compgen -d -- "$cur") )
2181 # variable names if appropriate shell option set and no completions
2182 if shopt -q cdable_vars && [[ $@{#COMPREPLY[@@]@} -eq 0 ]]; then
2183 COMPREPLY=( $(compgen -v -- "$cur") )
2190 We install the completion function using the @option{-F} option to
2194 # Tell readline to quote appropriate and append slashes to directories;
2195 # use the bash default completion for other arguments
2196 complete -o filenames -o nospace -o bashdefault -F _comp_cd cd
2200 Since we'd like Bash and Readline to take care of some
2201 of the other details for us, we use several other options to tell Bash
2202 and Readline what to do. The @option{-o filenames} option tells Readline
2203 that the possible completions should be treated as filenames, and quoted
2204 appropriately. That option will also cause Readline to append a slash to
2205 filenames it can determine are directories (which is why we might want to
2206 extend @code{_comp_cd} to append a slash if we're using directories found
2207 via @var{CDPATH}: Readline can't tell those completions are directories).
2208 The @option{-o nospace} option tells Readline to not append a space
2209 character to the directory name, in case we want to append to it.
2210 The @option{-o bashdefault} option brings in the rest of the "Bash default"
2211 completions -- possible completion that Bash adds to the default Readline
2212 set. These include things like command name completion, variable completion
2213 for words beginning with @samp{@{}, completions containing pathname
2214 expansion patterns (@pxref{Filename Expansion}), and so on.
2216 Once installed using @code{complete}, @code{_comp_cd} will be called every
2217 time we attempt word completion for a @code{cd} command.
2219 Many more examples -- an extensive collection of completions for most of
2220 the common GNU, Unix, and Linux commands -- are available as part of the
2221 bash_completion project. This is installed by default on many GNU/Linux
2222 distributions. Originally written by Ian Macdonald, the project now lives
2223 at @url{http://bash-completion.alioth.debian.org/}. There are ports for
2224 other systems such as Solaris and Mac OS X.
2226 An older version of the bash_completion package is distributed with bash
2227 in the @file{examples/complete} subdirectory.