1@comment %**start of header (This is for running Texinfo on a region.)
2@setfilename rluser.info
3@comment %**end of header (This is for running Texinfo on a region.)
4@setchapternewpage odd
5
6@ignore
7This file documents the end user interface to the GNU command line
8editing features. It is to be an appendix to manuals for programs which
9use these features. There is a document entitled "readline.texinfo"
10which contains both end-user and programmer documentation for the
11GNU Readline Library.
12
13Copyright (C) 1988-2004 Free Software Foundation, Inc.
14
15Authored by Brian Fox and Chet Ramey.
16
17Permission is granted to process this file through Tex and print the
18results, provided the printed document carries copying permission notice
19identical to this one except for the removal of this paragraph (this
20paragraph not being relevant to the printed manual).
21
22Permission is granted to make and distribute verbatim copies of this manual
23provided the copyright notice and this permission notice are preserved on
24all copies.
25
26Permission is granted to copy and distribute modified versions of this
27manual under the conditions for verbatim copying, provided also that the
28GNU Copyright statement is available to the distributee, and provided that
29the entire resulting derived work is distributed under the terms of a
30permission notice identical to this one.
31
32Permission is granted to copy and distribute translations of this manual
33into another language, under the above conditions for modified versions.
34@end ignore
35
36@comment If you are including this manual as an appendix, then set the
37@comment variable readline-appendix.
38
39@ifclear BashFeatures
40@defcodeindex bt
41@end ifclear
42
43@node Command Line Editing
44@chapter Command Line Editing
45
46This chapter describes the basic features of the @sc{gnu}
47command line editing interface.
48@ifset BashFeatures
49Command line editing is provided by the Readline library, which is
50used by several different programs, including Bash.
51@end ifset
52
53@menu
54* Introduction and Notation:: Notation used in this text.
55* Readline Interaction:: The minimum set of commands for editing a line.
56* Readline Init File:: Customizing Readline from a user's view.
57* Bindable Readline Commands:: A description of most of the Readline commands
58 available for binding
59* Readline vi Mode:: A short description of how to make Readline
60 behave like the vi editor.
61@ifset BashFeatures
62* Programmable Completion:: How to specify the possible completions for
63 a specific command.
64* Programmable Completion Builtins:: Builtin commands to specify how to
65 complete arguments for a particular command.
66@end ifset
67@end menu
68
69@node Introduction and Notation
70@section Introduction to Line Editing
71
72The following paragraphs describe the notation used to represent
73keystrokes.
74
75The text @kbd{C-k} is read as `Control-K' and describes the character
76produced when the @key{k} key is pressed while the Control key
77is depressed.
78
79The text @kbd{M-k} is read as `Meta-K' and describes the character
80produced when the Meta key (if you have one) is depressed, and the @key{k}
81key is pressed.
82The Meta key is labeled @key{ALT} on many keyboards.
83On keyboards with two keys labeled @key{ALT} (usually to either side of
84the space bar), the @key{ALT} on the left side is generally set to
85work as a Meta key.
86The @key{ALT} key on the right may also be configured to work as a
87Meta key or may be configured as some other modifier, such as a
88Compose key for typing accented characters.
89
90If you do not have a Meta or @key{ALT} key, or another key working as
91a Meta key, the identical keystroke can be generated by typing @key{ESC}
92@emph{first}, and then typing @key{k}.
93Either process is known as @dfn{metafying} the @key{k} key.
94
95The text @kbd{M-C-k} is read as `Meta-Control-k' and describes the
96character produced by @dfn{metafying} @kbd{C-k}.
97
98In addition, several keys have their own names. Specifically,
99@key{DEL}, @key{ESC}, @key{LFD}, @key{SPC}, @key{RET}, and @key{TAB} all
100stand for themselves when seen in this text, or in an init file
101(@pxref{Readline Init File}).
102If your keyboard lacks a @key{LFD} key, typing @key{C-j} will
103produce the desired character.
104The @key{RET} key may be labeled @key{Return} or @key{Enter} on
105some keyboards.
106
107@node Readline Interaction
108@section Readline Interaction
109@cindex interaction, readline
110
111Often during an interactive session you type in a long line of text,
112only to notice that the first word on the line is misspelled. The
113Readline library gives you a set of commands for manipulating the text
114as you type it in, allowing you to just fix your typo, and not forcing
115you to retype the majority of the line. Using these editing commands,
116you move the cursor to the place that needs correction, and delete or
117insert the text of the corrections. Then, when you are satisfied with
118the line, you simply press @key{RET}. You do not have to be at the
119end of the line to press @key{RET}; the entire line is accepted
120regardless of the location of the cursor within the line.
121
122@menu
123* Readline Bare Essentials:: The least you need to know about Readline.
124* Readline Movement Commands:: Moving about the input line.
125* Readline Killing Commands:: How to delete text, and how to get it back!
126* Readline Arguments:: Giving numeric arguments to commands.
127* Searching:: Searching through previous lines.
128@end menu
129
130@node Readline Bare Essentials
131@subsection Readline Bare Essentials
132@cindex notation, readline
133@cindex command editing
134@cindex editing command lines
135
136In order to enter characters into the line, simply type them. The typed
137character appears where the cursor was, and then the cursor moves one
138space to the right. If you mistype a character, you can use your
139erase character to back up and delete the mistyped character.
140
141Sometimes you may mistype a character, and
142not notice the error until you have typed several other characters. In
143that case, you can type @kbd{C-b} to move the cursor to the left, and then
144correct your mistake. Afterwards, you can move the cursor to the right
145with @kbd{C-f}.
146
147When you add text in the middle of a line, you will notice that characters
148to the right of the cursor are `pushed over' to make room for the text
149that you have inserted. Likewise, when you delete text behind the cursor,
150characters to the right of the cursor are `pulled back' to fill in the
151blank space created by the removal of the text. A list of the bare
152essentials for editing the text of an input line follows.
153
154@table @asis
155@item @kbd{C-b}
156Move back one character.
157@item @kbd{C-f}
158Move forward one character.
159@item @key{DEL} or @key{Backspace}
160Delete the character to the left of the cursor.
161@item @kbd{C-d}
162Delete the character underneath the cursor.
163@item @w{Printing characters}
164Insert the character into the line at the cursor.
165@item @kbd{C-_} or @kbd{C-x C-u}
166Undo the last editing command. You can undo all the way back to an
167empty line.
168@end table
169
170@noindent
171(Depending on your configuration, the @key{Backspace} key be set to
172delete the character to the left of the cursor and the @key{DEL} key set
173to delete the character underneath the cursor, like @kbd{C-d}, rather
174than the character to the left of the cursor.)
175
176@node Readline Movement Commands
177@subsection Readline Movement Commands
178
179
180The above table describes the most basic keystrokes that you need
181in order to do editing of the input line. For your convenience, many
182other commands have been added in addition to @kbd{C-b}, @kbd{C-f},
183@kbd{C-d}, and @key{DEL}. Here are some commands for moving more rapidly
184about the line.
185
186@table @kbd
187@item C-a
188Move to the start of the line.
189@item C-e
190Move to the end of the line.
191@item M-f
192Move forward a word, where a word is composed of letters and digits.
193@item M-b
194Move backward a word.
195@item C-l
196Clear the screen, reprinting the current line at the top.
197@end table
198
199Notice how @kbd{C-f} moves forward a character, while @kbd{M-f} moves
200forward a word. It is a loose convention that control keystrokes
201operate on characters while meta keystrokes operate on words.
202
203@node Readline Killing Commands
204@subsection Readline Killing Commands
205
206@cindex killing text
207@cindex yanking text
208
209@dfn{Killing} text means to delete the text from the line, but to save
210it away for later use, usually by @dfn{yanking} (re-inserting)
211it back into the line.
212(`Cut' and `paste' are more recent jargon for `kill' and `yank'.)
213
214If the description for a command says that it `kills' text, then you can
215be sure that you can get the text back in a different (or the same)
216place later.
217
218When you use a kill command, the text is saved in a @dfn{kill-ring}.
219Any number of consecutive kills save all of the killed text together, so
220that when you yank it back, you get it all. The kill
221ring is not line specific; the text that you killed on a previously
222typed line is available to be yanked back later, when you are typing
223another line.
224@cindex kill ring
225
226Here is the list of commands for killing text.
227
228@table @kbd
229@item C-k
230Kill the text from the current cursor position to the end of the line.
231
232@item M-d
233Kill from the cursor to the end of the current word, or, if between
234words, to the end of the next word.
235Word boundaries are the same as those used by @kbd{M-f}.
236
237@item M-@key{DEL}
238Kill from the cursor the start of the current word, or, if between
239words, to the start of the previous word.
240Word boundaries are the same as those used by @kbd{M-b}.
241
242@item C-w
243Kill from the cursor to the previous whitespace. This is different than
244@kbd{M-@key{DEL}} because the word boundaries differ.
245
246@end table
247
248Here is how to @dfn{yank} the text back into the line. Yanking
249means to copy the most-recently-killed text from the kill buffer.
250
251@table @kbd
252@item C-y
253Yank the most recently killed text back into the buffer at the cursor.
254
255@item M-y
256Rotate the kill-ring, and yank the new top. You can only do this if
257the prior command is @kbd{C-y} or @kbd{M-y}.
258@end table
259
260@node Readline Arguments
261@subsection Readline Arguments
262
263You can pass numeric arguments to Readline commands. Sometimes the
264argument acts as a repeat count, other times it is the @i{sign} of the
265argument that is significant. If you pass a negative argument to a
266command which normally acts in a forward direction, that command will
267act in a backward direction. For example, to kill text back to the
268start of the line, you might type @samp{M-- C-k}.
269
270The general way to pass numeric arguments to a command is to type meta
271digits before the command. If the first `digit' typed is a minus
272sign (@samp{-}), then the sign of the argument will be negative. Once
273you have typed one meta digit to get the argument started, you can type
274the remainder of the digits, and then the command. For example, to give
275the @kbd{C-d} command an argument of 10, you could type @samp{M-1 0 C-d},
276which will delete the next ten characters on the input line.
277
278@node Searching
279@subsection Searching for Commands in the History
280
281Readline provides commands for searching through the command history
282@ifset BashFeatures
283(@pxref{Bash History Facilities})
284@end ifset
285for lines containing a specified string.
286There are two search modes: @dfn{incremental} and @dfn{non-incremental}.
287
288Incremental searches begin before the user has finished typing the
289search string.
290As each character of the search string is typed, Readline displays
291the next entry from the history matching the string typed so far.
292An incremental search requires only as many characters as needed to
293find the desired history entry.
294To search backward in the history for a particular string, type
295@kbd{C-r}. Typing @kbd{C-s} searches forward through the history.
296The characters present in the value of the @code{isearch-terminators} variable
297are used to terminate an incremental search.
298If that variable has not been assigned a value, the @key{ESC} and
299@kbd{C-J} characters will terminate an incremental search.
300@kbd{C-g} will abort an incremental search and restore the original line.
301When the search is terminated, the history entry containing the
302search string becomes the current line.
303
304To find other matching entries in the history list, type @kbd{C-r} or
305@kbd{C-s} as appropriate.
306This will search backward or forward in the history for the next
307entry matching the search string typed so far.
308Any other key sequence bound to a Readline command will terminate
309the search and execute that command.
310For instance, a @key{RET} will terminate the search and accept
311the line, thereby executing the command from the history list.
312A movement command will terminate the search, make the last line found
313the current line, and begin editing.
314
315Readline remembers the last incremental search string. If two
316@kbd{C-r}s are typed without any intervening characters defining a new
317search string, any remembered search string is used.
318
319Non-incremental searches read the entire search string before starting
320to search for matching history lines. The search string may be
321typed by the user or be part of the contents of the current line.
322
323@node Readline Init File
324@section Readline Init File
325@cindex initialization file, readline
326
327Although the Readline library comes with a set of Emacs-like
328keybindings installed by default, it is possible to use a different set
329of keybindings.
330Any user can customize programs that use Readline by putting
331commands in an @dfn{inputrc} file, conventionally in his home directory.
332The name of this
333@ifset BashFeatures
334file is taken from the value of the shell variable @env{INPUTRC}. If
335@end ifset
336@ifclear BashFeatures
337file is taken from the value of the environment variable @env{INPUTRC}. If
338@end ifclear
339that variable is unset, the default is @file{~/.inputrc}.
340
341When a program which uses the Readline library starts up, the
342init file is read, and the key bindings are set.
343
344In addition, the @code{C-x C-r} command re-reads this init file, thus
345incorporating any changes that you might have made to it.
346
347@menu
348* Readline Init File Syntax:: Syntax for the commands in the inputrc file.
349
350* Conditional Init Constructs:: Conditional key bindings in the inputrc file.
351
352* Sample Init File:: An example inputrc file.
353@end menu
354
355@node Readline Init File Syntax
356@subsection Readline Init File Syntax
357
358There are only a few basic constructs allowed in the
359Readline init file. Blank lines are ignored.
360Lines beginning with a @samp{#} are comments.
361Lines beginning with a @samp{$} indicate conditional
362constructs (@pxref{Conditional Init Constructs}). Other lines
363denote variable settings and key bindings.
364
365@table @asis
366@item Variable Settings
367You can modify the run-time behavior of Readline by
368altering the values of variables in Readline
369using the @code{set} command within the init file.
370The syntax is simple:
371
372@example
373set @var{variable} @var{value}
374@end example
375
376@noindent
377Here, for example, is how to
378change from the default Emacs-like key binding to use
379@code{vi} line editing commands:
380
381@example
382set editing-mode vi
383@end example
384
385Variable names and values, where appropriate, are recognized without regard
386to case.
387
388@ifset BashFeatures
389The @w{@code{bind -V}} command lists the current Readline variable names
390and values. @xref{Bash Builtins}.
391@end ifset
392
393A great deal of run-time behavior is changeable with the following
394variables.
395
396@cindex variables, readline
397@table @code
398
399@item bell-style
400@vindex bell-style
401Controls what happens when Readline wants to ring the terminal bell.
402If set to @samp{none}, Readline never rings the bell. If set to
403@samp{visible}, Readline uses a visible bell if one is available.
404If set to @samp{audible} (the default), Readline attempts to ring
405the terminal's bell.
406
407@item comment-begin
408@vindex comment-begin
409The string to insert at the beginning of the line when the
410@code{insert-comment} command is executed. The default value
411is @code{"#"}.
412
413@item completion-ignore-case
414If set to @samp{on}, Readline performs filename matching and completion
415in a case-insensitive fashion.
416The default value is @samp{off}.
417
418@item completion-query-items
419@vindex completion-query-items
420The number of possible completions that determines when the user is
421asked whether the list of possibilities should be displayed.
422If the number of possible completions is greater than this value,
423Readline will ask the user whether or not he wishes to view
424them; otherwise, they are simply listed.
425This variable must be set to an integer value greater than or equal to 0.
426The default limit is @code{100}.
427
428@item convert-meta
429@vindex convert-meta
430If set to @samp{on}, Readline will convert characters with the
431eighth bit set to an @sc{ascii} key sequence by stripping the eighth
432bit and prefixing an @key{ESC} character, converting them to a
433meta-prefixed key sequence. The default value is @samp{on}.
434
435@item disable-completion
436@vindex disable-completion
437If set to @samp{On}, Readline will inhibit word completion.
438Completion characters will be inserted into the line as if they had
439been mapped to @code{self-insert}. The default is @samp{off}.
440
441@item editing-mode
442@vindex editing-mode
443The @code{editing-mode} variable controls which default set of
444key bindings is used. By default, Readline starts up in Emacs editing
445mode, where the keystrokes are most similar to Emacs. This variable can be
446set to either @samp{emacs} or @samp{vi}.
447
448@item enable-keypad
449@vindex enable-keypad
450When set to @samp{on}, Readline will try to enable the application
451keypad when it is called. Some systems need this to enable the
452arrow keys. The default is @samp{off}.
453
454@item expand-tilde
455@vindex expand-tilde
456If set to @samp{on}, tilde expansion is performed when Readline
457attempts word completion. The default is @samp{off}.
458
459@vindex history-preserve-point
460If set to @samp{on}, the history code attempts to place point at the
461same location on each history line retrieved with @code{previous-history}
462or @code{next-history}.
463
464@item horizontal-scroll-mode
465@vindex horizontal-scroll-mode
466This variable can be set to either @samp{on} or @samp{off}. Setting it
467to @samp{on} means that the text of the lines being edited will scroll
468horizontally on a single screen line when they are longer than the width
469of the screen, instead of wrapping onto a new screen line. By default,
470this variable is set to @samp{off}.
471
472@item input-meta
473@vindex input-meta
474@vindex meta-flag
475If set to @samp{on}, Readline will enable eight-bit input (it
476will not clear the eighth bit in the characters it reads),
477regardless of what the terminal claims it can support. The
478default value is @samp{off}. The name @code{meta-flag} is a
479synonym for this variable.
480
481@item isearch-terminators
482@vindex isearch-terminators
483The string of characters that should terminate an incremental search without
484subsequently executing the character as a command (@pxref{Searching}).
485If this variable has not been given a value, the characters @key{ESC} and
486@kbd{C-J} will terminate an incremental search.
487
488@item keymap
489@vindex keymap
490Sets Readline's idea of the current keymap for key binding commands.
491Acceptable @code{keymap} names are
492@code{emacs},
493@code{emacs-standard},
494@code{emacs-meta},
495@code{emacs-ctlx},
496@code{vi},
497@code{vi-move},
498@code{vi-command}, and
499@code{vi-insert}.
500@code{vi} is equivalent to @code{vi-command}; @code{emacs} is
501equivalent to @code{emacs-standard}. The default value is @code{emacs}.
502The value of the @code{editing-mode} variable also affects the
503default keymap.
504
505@item mark-directories
506If set to @samp{on}, completed directory names have a slash
507appended. The default is @samp{on}.
508
509@item mark-modified-lines
510@vindex mark-modified-lines
511This variable, when set to @samp{on}, causes Readline to display an
512asterisk (@samp{*}) at the start of history lines which have been modified.
513This variable is @samp{off} by default.
514
515@item mark-symlinked-directories
516@vindex mark-symlinked-directories
517If set to @samp{on}, completed names which are symbolic links
518to directories have a slash appended (subject to the value of
519@code{mark-directories}).
520The default is @samp{off}.
521
522@item match-hidden-files
523@vindex match-hidden-files
524This variable, when set to @samp{on}, causes Readline to match files whose
525names begin with a @samp{.} (hidden files) when performing filename
526completion, unless the leading @samp{.} is
527supplied by the user in the filename to be completed.
528This variable is @samp{on} by default.
529
530@item output-meta
531@vindex output-meta
532If set to @samp{on}, Readline will display characters with the
533eighth bit set directly rather than as a meta-prefixed escape
534sequence. The default is @samp{off}.
535
536@item page-completions
537@vindex page-completions
538If set to @samp{on}, Readline uses an internal @code{more}-like pager
539to display a screenful of possible completions at a time.
540This variable is @samp{on} by default.
541
542@item print-completions-horizontally
543If set to @samp{on}, Readline will display completions with matches
544sorted horizontally in alphabetical order, rather than down the screen.
545The default is @samp{off}.
546
547@item show-all-if-ambiguous
548@vindex show-all-if-ambiguous
549This alters the default behavior of the completion functions. If
550set to @samp{on},
551words which have more than one possible completion cause the
552matches to be listed immediately instead of ringing the bell.
553The default value is @samp{off}.
554
555@item show-all-if-unmodified
556@vindex show-all-if-unmodified
557This alters the default behavior of the completion functions in
558a fashion similar to @var{show-all-if-ambiguous}.
559If set to @samp{on},
560words which have more than one possible completion without any
561possible partial completion (the possible completions don't share
562a common prefix) cause the matches to be listed immediately instead
563of ringing the bell.
564The default value is @samp{off}.
565
566@item visible-stats
567@vindex visible-stats
568If set to @samp{on}, a character denoting a file's type
569is appended to the filename when listing possible
570completions. The default is @samp{off}.
571
572@end table
573
574@item Key Bindings
575The syntax for controlling key bindings in the init file is
576simple. First you need to find the name of the command that you
577want to change. The following sections contain tables of the command
578name, the default keybinding, if any, and a short description of what
579the command does.
580
581Once you know the name of the command, simply place on a line
582in the init file the name of the key
583you wish to bind the command to, a colon, and then the name of the
584command. The name of the key
585can be expressed in different ways, depending on what you find most
586comfortable.
587
588In addition to command names, readline allows keys to be bound
589to a string that is inserted when the key is pressed (a @var{macro}).
590
591@ifset BashFeatures
592The @w{@code{bind -p}} command displays Readline function names and
593bindings in a format that can put directly into an initialization file.
594@xref{Bash Builtins}.
595@end ifset
596
597@table @asis
598@item @w{@var{keyname}: @var{function-name} or @var{macro}}
599@var{keyname} is the name of a key spelled out in English. For example:
600@example
601Control-u: universal-argument
602Meta-Rubout: backward-kill-word
603Control-o: "> output"
604@end example
605
606In the above example, @kbd{C-u} is bound to the function
607@code{universal-argument},
608@kbd{M-DEL} is bound to the function @code{backward-kill-word}, and
609@kbd{C-o} is bound to run the macro
610expressed on the right hand side (that is, to insert the text
611@samp{> output} into the line).
612
613A number of symbolic character names are recognized while
614processing this key binding syntax:
615@var{DEL},
616@var{ESC},
617@var{ESCAPE},
618@var{LFD},
619@var{NEWLINE},
620@var{RET},
621@var{RETURN},
622@var{RUBOUT},
623@var{SPACE},
624@var{SPC},
625and
626@var{TAB}.
627
628@item @w{"@var{keyseq}": @var{function-name} or @var{macro}}
629@var{keyseq} differs from @var{keyname} above in that strings
630denoting an entire key sequence can be specified, by placing
631the key sequence in double quotes. Some @sc{gnu} Emacs style key
632escapes can be used, as in the following example, but the
633special character names are not recognized.
634
635@example
636"\C-u": universal-argument
637"\C-x\C-r": re-read-init-file
638"\e[11~": "Function Key 1"
639@end example
640
641In the above example, @kbd{C-u} is again bound to the function
642@code{universal-argument} (just as it was in the first example),
643@samp{@kbd{C-x} @kbd{C-r}} is bound to the function @code{re-read-init-file},
644and @samp{@key{ESC} @key{[} @key{1} @key{1} @key{~}} is bound to insert
645the text @samp{Function Key 1}.
646
647@end table
648
649The following @sc{gnu} Emacs style escape sequences are available when
650specifying key sequences:
651
652@table @code
653@item @kbd{\C-}
654control prefix
655@item @kbd{\M-}
656meta prefix
657@item @kbd{\e}
658an escape character
659@item @kbd{\\}
660backslash
661@item @kbd{\"}
662@key{"}, a double quotation mark
663@item @kbd{\'}
664@key{'}, a single quote or apostrophe
665@end table
666
667In addition to the @sc{gnu} Emacs style escape sequences, a second
668set of backslash escapes is available:
669
670@table @code
671@item \a
672alert (bell)
673@item \b
674backspace
675@item \d
676delete
677@item \f
678form feed
679@item \n
680newline
681@item \r
682carriage return
683@item \t
684horizontal tab
685@item \v
686vertical tab
687@item \@var{nnn}
688the eight-bit character whose value is the octal value @var{nnn}
689(one to three digits)
690@item \x@var{HH}
691the eight-bit character whose value is the hexadecimal value @var{HH}
692(one or two hex digits)
693@end table
694
695When entering the text of a macro, single or double quotes must
696be used to indicate a macro definition.
697Unquoted text is assumed to be a function name.
698In the macro body, the backslash escapes described above are expanded.
699Backslash will quote any other character in the macro text,
700including @samp{"} and @samp{'}.
701For example, the following binding will make @samp{@kbd{C-x} \}
702insert a single @samp{\} into the line:
703@example
704"\C-x\\": "\\"
705@end example
706
707@end table
708
709@node Conditional Init Constructs
710@subsection Conditional Init Constructs
711
712Readline implements a facility similar in spirit to the conditional
713compilation features of the C preprocessor which allows key
714bindings and variable settings to be performed as the result
715of tests. There are four parser directives used.
716
717@table @code
718@item $if
719The @code{$if} construct allows bindings to be made based on the
720editing mode, the terminal being used, or the application using
721Readline. The text of the test extends to the end of the line;
722no characters are required to isolate it.
723
724@table @code
725@item mode
726The @code{mode=} form of the @code{$if} directive is used to test
727whether Readline is in @code{emacs} or @code{vi} mode.
728This may be used in conjunction
729with the @samp{set keymap} command, for instance, to set bindings in
730the @code{emacs-standard} and @code{emacs-ctlx} keymaps only if
731Readline is starting out in @code{emacs} mode.
732
733@item term
734The @code{term=} form may be used to include terminal-specific
735key bindings, perhaps to bind the key sequences output by the
736terminal's function keys. The word on the right side of the
737@samp{=} is tested against both the full name of the terminal and
738the portion of the terminal name before the first @samp{-}. This
739allows @code{sun} to match both @code{sun} and @code{sun-cmd},
740for instance.
741
742@item application
743The @var{application} construct is used to include
744application-specific settings. Each program using the Readline
745library sets the @var{application name}, and you can test for
746a particular value.
747This could be used to bind key sequences to functions useful for
748a specific program. For instance, the following command adds a
749key sequence that quotes the current or previous word in Bash:
750@example
751$if Bash
752# Quote the current or previous word
753"\C-xq": "\eb\"\ef\""
754$endif
755@end example
756@end table
757
758@item $endif
759This command, as seen in the previous example, terminates an
760@code{$if} command.
761
762@item $else
763Commands in this branch of the @code{$if} directive are executed if
764the test fails.
765
766@item $include
767This directive takes a single filename as an argument and reads commands
768and bindings from that file.
769For example, the following directive reads from @file{/etc/inputrc}:
770@example
771$include /etc/inputrc
772@end example
773@end table
774
775@node Sample Init File
776@subsection Sample Init File
777
778Here is an example of an @var{inputrc} file. This illustrates key
779binding, variable assignment, and conditional syntax.
780
781@example
782@page
783# This file controls the behaviour of line input editing for
784# programs that use the GNU Readline library. Existing
785# programs include FTP, Bash, and GDB.
786#
787# You can re-read the inputrc file with C-x C-r.
788# Lines beginning with '#' are comments.
789#
790# First, include any systemwide bindings and variable
791# assignments from /etc/Inputrc
792$include /etc/Inputrc
793
794#
795# Set various bindings for emacs mode.
796
797set editing-mode emacs
798
799$if mode=emacs
800
801Meta-Control-h: backward-kill-word Text after the function name is ignored
802
803#
804# Arrow keys in keypad mode
805#
806#"\M-OD": backward-char
807#"\M-OC": forward-char
808#"\M-OA": previous-history
809#"\M-OB": next-history
810#
811# Arrow keys in ANSI mode
812#
813"\M-[D": backward-char
814"\M-[C": forward-char
815"\M-[A": previous-history
816"\M-[B": next-history
817#
818# Arrow keys in 8 bit keypad mode
819#
820#"\M-\C-OD": backward-char
821#"\M-\C-OC": forward-char
822#"\M-\C-OA": previous-history
823#"\M-\C-OB": next-history
824#
825# Arrow keys in 8 bit ANSI mode
826#
827#"\M-\C-[D": backward-char
828#"\M-\C-[C": forward-char
829#"\M-\C-[A": previous-history
830#"\M-\C-[B": next-history
831
832C-q: quoted-insert
833
834$endif
835
836# An old-style binding. This happens to be the default.
837TAB: complete
838
839# Macros that are convenient for shell interaction
840$if Bash
841# edit the path
842"\C-xp": "PATH=$@{PATH@}\e\C-e\C-a\ef\C-f"
843# prepare to type a quoted word --
844# insert open and close double quotes
845# and move to just after the open quote
846"\C-x\"": "\"\"\C-b"
847# insert a backslash (testing backslash escapes
848# in sequences and macros)
849"\C-x\\": "\\"
850# Quote the current or previous word
851"\C-xq": "\eb\"\ef\""
852# Add a binding to refresh the line, which is unbound
853"\C-xr": redraw-current-line
854# Edit variable on current line.
855"\M-\C-v": "\C-a\C-k$\C-y\M-\C-e\C-a\C-y="
856$endif
857
858# use a visible bell if one is available
859set bell-style visible
860
861# don't strip characters to 7 bits when reading
862set input-meta on
863
864# allow iso-latin1 characters to be inserted rather
865# than converted to prefix-meta sequences
866set convert-meta off
867
868# display characters with the eighth bit set directly
869# rather than as meta-prefixed characters
870set output-meta on
871
872# if there are more than 150 possible completions for
873# a word, ask the user if he wants to see all of them
874set completion-query-items 150
875
876# For FTP
877$if Ftp
878"\C-xg": "get \M-?"
879"\C-xt": "put \M-?"
880"\M-.": yank-last-arg
881$endif
882@end example
883
884@node Bindable Readline Commands
885@section Bindable Readline Commands
886
887@menu
888* Commands For Moving:: Moving about the line.
889* Commands For History:: Getting at previous lines.
890* Commands For Text:: Commands for changing text.
891* Commands For Killing:: Commands for killing and yanking.
892* Numeric Arguments:: Specifying numeric arguments, repeat counts.
893* Commands For Completion:: Getting Readline to do the typing for you.
894* Keyboard Macros:: Saving and re-executing typed characters
895* Miscellaneous Commands:: Other miscellaneous commands.
896@end menu
897
898This section describes Readline commands that may be bound to key
899sequences.
900@ifset BashFeatures
901You can list your key bindings by executing
902@w{@code{bind -P}} or, for a more terse format, suitable for an
903@var{inputrc} file, @w{@code{bind -p}}. (@xref{Bash Builtins}.)
904@end ifset
905Command names without an accompanying key sequence are unbound by default.
906
907In the following descriptions, @dfn{point} refers to the current cursor
908position, and @dfn{mark} refers to a cursor position saved by the
909@code{set-mark} command.
910The text between the point and mark is referred to as the @dfn{region}.
911
912@node Commands For Moving
913@subsection Commands For Moving
914@ftable @code
915@item beginning-of-line (C-a)
916Move to the start of the current line.
917
918@item end-of-line (C-e)
919Move to the end of the line.
920
921@item forward-char (C-f)
922Move forward a character.
923
924@item backward-char (C-b)
925Move back a character.
926
927@item forward-word (M-f)
928Move forward to the end of the next word. Words are composed of
929letters and digits.
930
931@item backward-word (M-b)
932Move back to the start of the current or previous word. Words are
933composed of letters and digits.
934
935@item clear-screen (C-l)
936Clear the screen and redraw the current line,
937leaving the current line at the top of the screen.
938
939@item redraw-current-line ()
940Refresh the current line. By default, this is unbound.
941
942@end ftable
943
944@node Commands For History
945@subsection Commands For Manipulating The History
946
947@ftable @code
948@item accept-line (Newline or Return)
949@ifset BashFeatures
950Accept the line regardless of where the cursor is.
951If this line is
952non-empty, add it to the history list according to the setting of
953the @env{HISTCONTROL} and @env{HISTIGNORE} variables.
954If this line is a modified history line, then restore the history line
955to its original state.
956@end ifset
957@ifclear BashFeatures
958Accept the line regardless of where the cursor is.
959If this line is
960non-empty, it may be added to the history list for future recall with
961@code{add_history()}.
962If this line is a modified history line, the history line is restored
963to its original state.
964@end ifclear
965
966@item previous-history (C-p)
967Move `back' through the history list, fetching the previous command.
968
969@item next-history (C-n)
970Move `forward' through the history list, fetching the next command.
971
972@item beginning-of-history (M-<)
973Move to the first line in the history.
974
975@item end-of-history (M->)
976Move to the end of the input history, i.e., the line currently
977being entered.
978
979@item reverse-search-history (C-r)
980Search backward starting at the current line and moving `up' through
981the history as necessary. This is an incremental search.
982
983@item forward-search-history (C-s)
984Search forward starting at the current line and moving `down' through
985the the history as necessary. This is an incremental search.
986
987@item non-incremental-reverse-search-history (M-p)
988Search backward starting at the current line and moving `up'
989through the history as necessary using a non-incremental search
990for a string supplied by the user.
991
992@item non-incremental-forward-search-history (M-n)
993Search forward starting at the current line and moving `down'
994through the the history as necessary using a non-incremental search
995for a string supplied by the user.
996
997@item history-search-forward ()
998Search forward through the history for the string of characters
999between the start of the current line and the point.
1000This is a non-incremental search.
1001By default, this command is unbound.
1002
1003@item history-search-backward ()
1004Search backward through the history for the string of characters
1005between the start of the current line and the point. This
1006is a non-incremental search. By default, this command is unbound.
1007
1008@item yank-nth-arg (M-C-y)
1009Insert the first argument to the previous command (usually
1010the second word on the previous line) at point.
1011With an argument @var{n},
1012insert the @var{n}th word from the previous command (the words
1013in the previous command begin with word 0). A negative argument
1014inserts the @var{n}th word from the end of the previous command.
1015
1016@item yank-last-arg (M-. or M-_)
1017Insert last argument to the previous command (the last word of the
1018previous history entry). With an
1019argument, behave exactly like @code{yank-nth-arg}.
1020Successive calls to @code{yank-last-arg} move back through the history
1021list, inserting the last argument of each line in turn.
1022
1023@end ftable
1024
1025@node Commands For Text
1026@subsection Commands For Changing Text
1027
1028@ftable @code
1029@item delete-char (C-d)
1030Delete the character at point. If point is at the
1031beginning of the line, there are no characters in the line, and
1032the last character typed was not bound to @code{delete-char}, then
1033return @sc{eof}.
1034
1035@item backward-delete-char (Rubout)
1036Delete the character behind the cursor. A numeric argument means
1037to kill the characters instead of deleting them.
1038
1039@item forward-backward-delete-char ()
1040Delete the character under the cursor, unless the cursor is at the
1041end of the line, in which case the character behind the cursor is
1042deleted. By default, this is not bound to a key.
1043
1044@item quoted-insert (C-q or C-v)
1045Add the next character typed to the line verbatim. This is
1046how to insert key sequences like @kbd{C-q}, for example.
1047
1048@ifclear BashFeatures
1049@item tab-insert (M-@key{TAB})
1050Insert a tab character.
1051@end ifclear
1052
1053@item self-insert (a, b, A, 1, !, @dots{})
1054Insert yourself.
1055
1056@item transpose-chars (C-t)
1057Drag the character before the cursor forward over
1058the character at the cursor, moving the
1059cursor forward as well. If the insertion point
1060is at the end of the line, then this
1061transposes the last two characters of the line.
1062Negative arguments have no effect.
1063
1064@item transpose-words (M-t)
1065Drag the word before point past the word after point,
1066moving point past that word as well.
1067If the insertion point is at the end of the line, this transposes
1068the last two words on the line.
1069
1070@item upcase-word (M-u)
1071Uppercase the current (or following) word. With a negative argument,
1072uppercase the previous word, but do not move the cursor.
1073
1074@item downcase-word (M-l)
1075Lowercase the current (or following) word. With a negative argument,
1076lowercase the previous word, but do not move the cursor.
1077
1078@item capitalize-word (M-c)
1079Capitalize the current (or following) word. With a negative argument,
1080capitalize the previous word, but do not move the cursor.
1081
1082@item overwrite-mode ()
1083Toggle overwrite mode. With an explicit positive numeric argument,
1084switches to overwrite mode. With an explicit non-positive numeric
1085argument, switches to insert mode. This command affects only
1086@code{emacs} mode; @code{vi} mode does overwrite differently.
1087Each call to @code{readline()} starts in insert mode.
1088
1089In overwrite mode, characters bound to @code{self-insert} replace
1090the text at point rather than pushing the text to the right.
1091Characters bound to @code{backward-delete-char} replace the character
1092before point with a space.
1093
1094By default, this command is unbound.
1095
1096@end ftable
1097
1098@node Commands For Killing
1099@subsection Killing And Yanking
1100
1101@ftable @code
1102
1103@item kill-line (C-k)
1104Kill the text from point to the end of the line.
1105
1106@item backward-kill-line (C-x Rubout)
1107Kill backward to the beginning of the line.
1108
1109@item unix-line-discard (C-u)
1110Kill backward from the cursor to the beginning of the current line.
1111
1112@item kill-whole-line ()
1113Kill all characters on the current line, no matter where point is.
1114By default, this is unbound.
1115
1116@item kill-word (M-d)
1117Kill from point to the end of the current word, or if between
1118words, to the end of the next word.
1119Word boundaries are the same as @code{forward-word}.
1120
1121@item backward-kill-word (M-@key{DEL})
1122Kill the word behind point.
1123Word boundaries are the same as @code{backward-word}.
1124
1125@item unix-word-rubout (C-w)
1126Kill the word behind point, using white space as a word boundary.
1127The killed text is saved on the kill-ring.
1128
1129@item unix-filename-rubout ()
1130Kill the word behind point, using white space and the slash character
1131as the word boundaries.
1132The killed text is saved on the kill-ring.
1133
1134@item delete-horizontal-space ()
1135Delete all spaces and tabs around point. By default, this is unbound.
1136
1137@item kill-region ()
1138Kill the text in the current region.
1139By default, this command is unbound.
1140
1141@item copy-region-as-kill ()
1142Copy the text in the region to the kill buffer, so it can be yanked
1143right away. By default, this command is unbound.
1144
1145@item copy-backward-word ()
1146Copy the word before point to the kill buffer.
1147The word boundaries are the same as @code{backward-word}.
1148By default, this command is unbound.
1149
1150@item copy-forward-word ()
1151Copy the word following point to the kill buffer.
1152The word boundaries are the same as @code{forward-word}.
1153By default, this command is unbound.
1154
1155@item yank (C-y)
1156Yank the top of the kill ring into the buffer at point.
1157
1158@item yank-pop (M-y)
1159Rotate the kill-ring, and yank the new top. You can only do this if
1160the prior command is @code{yank} or @code{yank-pop}.
1161@end ftable
1162
1163@node Numeric Arguments
1164@subsection Specifying Numeric Arguments
1165@ftable @code
1166
1167@item digit-argument (@kbd{M-0}, @kbd{M-1}, @dots{} @kbd{M--})
1168Add this digit to the argument already accumulating, or start a new
1169argument. @kbd{M--} starts a negative argument.
1170
1171@item universal-argument ()
1172This is another way to specify an argument.
1173If this command is followed by one or more digits, optionally with a
1174leading minus sign, those digits define the argument.
1175If the command is followed by digits, executing @code{universal-argument}
1176again ends the numeric argument, but is otherwise ignored.
1177As a special case, if this command is immediately followed by a
1178character that is neither a digit or minus sign, the argument count
1179for the next command is multiplied by four.
1180The argument count is initially one, so executing this function the
1181first time makes the argument count four, a second time makes the
1182argument count sixteen, and so on.
1183By default, this is not bound to a key.
1184@end ftable
1185
1186@node Commands For Completion
1187@subsection Letting Readline Type For You
1188
1189@ftable @code
1190@item complete (@key{TAB})
1191Attempt to perform completion on the text before point.
1192The actual completion performed is application-specific.
1193@ifset BashFeatures
1194Bash attempts completion treating the text as a variable (if the
1195text begins with @samp{$}), username (if the text begins with
1196@samp{~}), hostname (if the text begins with @samp{@@}), or
1197command (including aliases and functions) in turn. If none
1198of these produces a match, filename completion is attempted.
1199@end ifset
1200@ifclear BashFeatures
1201The default is filename completion.
1202@end ifclear
1203
1204@item possible-completions (M-?)
1205List the possible completions of the text before point.
1206
1207@item insert-completions (M-*)
1208Insert all completions of the text before point that would have
1209been generated by @code{possible-completions}.
1210
1211@item menu-complete ()
1212Similar to @code{complete}, but replaces the word to be completed
1213with a single match from the list of possible completions.
1214Repeated execution of @code{menu-complete} steps through the list
1215of possible completions, inserting each match in turn.
1216At the end of the list of completions, the bell is rung
1217(subject to the setting of @code{bell-style})
1218and the original text is restored.
1219An argument of @var{n} moves @var{n} positions forward in the list
1220of matches; a negative argument may be used to move backward
1221through the list.
1222This command is intended to be bound to @key{TAB}, but is unbound
1223by default.
1224
1225@item delete-char-or-list ()
1226Deletes the character under the cursor if not at the beginning or
1227end of the line (like @code{delete-char}).
1228If at the end of the line, behaves identically to
1229@code{possible-completions}.
1230This command is unbound by default.
1231
1232@ifset BashFeatures
1233@item complete-filename (M-/)
1234Attempt filename completion on the text before point.
1235
1236@item possible-filename-completions (C-x /)
1237List the possible completions of the text before point,
1238treating it as a filename.
1239
1240@item complete-username (M-~)
1241Attempt completion on the text before point, treating
1242it as a username.
1243
1244@item possible-username-completions (C-x ~)
1245List the possible completions of the text before point,
1246treating it as a username.
1247
1248@item complete-variable (M-$)
1249Attempt completion on the text before point, treating
1250it as a shell variable.
1251
1252@item possible-variable-completions (C-x $)
1253List the possible completions of the text before point,
1254treating it as a shell variable.
1255
1256@item complete-hostname (M-@@)
1257Attempt completion on the text before point, treating
1258it as a hostname.
1259
1260@item possible-hostname-completions (C-x @@)
1261List the possible completions of the text before point,
1262treating it as a hostname.
1263
1264@item complete-command (M-!)
1265Attempt completion on the text before point, treating
1266it as a command name. Command completion attempts to
1267match the text against aliases, reserved words, shell
1268functions, shell builtins, and finally executable filenames,
1269in that order.
1270
1271@item possible-command-completions (C-x !)
1272List the possible completions of the text before point,
1273treating it as a command name.
1274
1275@item dynamic-complete-history (M-@key{TAB})
1276Attempt completion on the text before point, comparing
1277the text against lines from the history list for possible
1278completion matches.
1279
1280@item complete-into-braces (M-@{)
1281Perform filename completion and insert the list of possible completions
1282enclosed within braces so the list is available to the shell
1283(@pxref{Brace Expansion}).
1284
1285@end ifset
1286@end ftable
1287
1288@node Keyboard Macros
1289@subsection Keyboard Macros
1290@ftable @code
1291
1292@item start-kbd-macro (C-x ()
1293Begin saving the characters typed into the current keyboard macro.
1294
1295@item end-kbd-macro (C-x ))
1296Stop saving the characters typed into the current keyboard macro
1297and save the definition.
1298
1299@item call-last-kbd-macro (C-x e)
1300Re-execute the last keyboard macro defined, by making the characters
1301in the macro appear as if typed at the keyboard.
1302
1303@end ftable
1304
1305@node Miscellaneous Commands
1306@subsection Some Miscellaneous Commands
1307@ftable @code
1308
1309@item re-read-init-file (C-x C-r)
1310Read in the contents of the @var{inputrc} file, and incorporate
1311any bindings or variable assignments found there.
1312
1313@item abort (C-g)
1314Abort the current editing command and
1315ring the terminal's bell (subject to the setting of
1316@code{bell-style}).
1317
1318@item do-uppercase-version (M-a, M-b, M-@var{x}, @dots{})
1319If the metafied character @var{x} is lowercase, run the command
1320that is bound to the corresponding uppercase character.
1321
1322@item prefix-meta (@key{ESC})
1323Metafy the next character typed. This is for keyboards
1324without a meta key. Typing @samp{@key{ESC} f} is equivalent to typing
1325@kbd{M-f}.
1326
1327@item undo (C-_ or C-x C-u)
1328Incremental undo, separately remembered for each line.
1329
1330@item revert-line (M-r)
1331Undo all changes made to this line. This is like executing the @code{undo}
1332command enough times to get back to the beginning.
1333
1334@ifset BashFeatures
1335@item tilde-expand (M-&)
1336@end ifset
1337@ifclear BashFeatures
1338@item tilde-expand (M-~)
1339@end ifclear
1340Perform tilde expansion on the current word.
1341
1342@item set-mark (C-@@)
1343Set the mark to the point. If a
1344numeric argument is supplied, the mark is set to that position.
1345
1346@item exchange-point-and-mark (C-x C-x)
1347Swap the point with the mark. The current cursor position is set to
1348the saved position, and the old cursor position is saved as the mark.
1349
1350@item character-search (C-])
1351A character is read and point is moved to the next occurrence of that
1352character. A negative count searches for previous occurrences.
1353
1354@item character-search-backward (M-C-])
1355A character is read and point is moved to the previous occurrence
1356of that character. A negative count searches for subsequent
1357occurrences.
1358
1359@item insert-comment (M-#)
1360Without a numeric argument, the value of the @code{comment-begin}
1361variable is inserted at the beginning of the current line.
1362If a numeric argument is supplied, this command acts as a toggle: if
1363the characters at the beginning of the line do not match the value
1364of @code{comment-begin}, the value is inserted, otherwise
1365the characters in @code{comment-begin} are deleted from the beginning of
1366the line.
1367In either case, the line is accepted as if a newline had been typed.
1368@ifset BashFeatures
1369The default value of @code{comment-begin} causes this command
1370to make the current line a shell comment.
1371If a numeric argument causes the comment character to be removed, the line
1372will be executed by the shell.
1373@end ifset
1374
1375@item dump-functions ()
1376Print all of the functions and their key bindings to the
1377Readline output stream. If a numeric argument is supplied,
1378the output is formatted in such a way that it can be made part
1379of an @var{inputrc} file. This command is unbound by default.
1380
1381@item dump-variables ()
1382Print all of the settable variables and their values to the
1383Readline output stream. If a numeric argument is supplied,
1384the output is formatted in such a way that it can be made part
1385of an @var{inputrc} file. This command is unbound by default.
1386
1387@item dump-macros ()
1388Print all of the Readline key sequences bound to macros and the
1389strings they output. If a numeric argument is supplied,
1390the output is formatted in such a way that it can be made part
1391of an @var{inputrc} file. This command is unbound by default.
1392
1393@ifset BashFeatures
1394@item glob-complete-word (M-g)
1395The word before point is treated as a pattern for pathname expansion,
1396with an asterisk implicitly appended. This pattern is used to
1397generate a list of matching file names for possible completions.
1398
1399@item glob-expand-word (C-x *)
1400The word before point is treated as a pattern for pathname expansion,
1401and the list of matching file names is inserted, replacing the word.
1402If a numeric argument is supplied, a @samp{*} is appended before
1403pathname expansion.
1404
1405@item glob-list-expansions (C-x g)
1406The list of expansions that would have been generated by
1407@code{glob-expand-word} is displayed, and the line is redrawn.
1408If a numeric argument is supplied, a @samp{*} is appended before
1409pathname expansion.
1410
1411@item display-shell-version (C-x C-v)
1412Display version information about the current instance of Bash.
1413
1414@item shell-expand-line (M-C-e)
1415Expand the line as the shell does.
1416This performs alias and history expansion as well as all of the shell
1417word expansions (@pxref{Shell Expansions}).
1418
1419@item history-expand-line (M-^)
1420Perform history expansion on the current line.
1421
1422@item magic-space ()
1423Perform history expansion on the current line and insert a space
1424(@pxref{History Interaction}).
1425
1426@item alias-expand-line ()
1427Perform alias expansion on the current line (@pxref{Aliases}).
1428
1429@item history-and-alias-expand-line ()
1430Perform history and alias expansion on the current line.
1431
1432@item insert-last-argument (M-. or M-_)
1433A synonym for @code{yank-last-arg}.
1434
1435@item operate-and-get-next (C-o)
1436Accept the current line for execution and fetch the next line
1437relative to the current line from the history for editing. Any
1438argument is ignored.
1439
1440@item edit-and-execute-command (C-xC-e)
1441Invoke an editor on the current command line, and execute the result as shell
1442commands.
1443Bash attempts to invoke
1444@code{$VISUAL}, @code{$EDITOR}, and @code{emacs}
1445as the editor, in that order.
1446
1447@end ifset
1448
1449@ifclear BashFeatures
1450@item emacs-editing-mode (C-e)
1451When in @code{vi} command mode, this causes a switch to @code{emacs}
1452editing mode.
1453
1454@item vi-editing-mode (M-C-j)
1455When in @code{emacs} editing mode, this causes a switch to @code{vi}
1456editing mode.
1457
1458@end ifclear
1459
1460@end ftable
1461
1462@node Readline vi Mode
1463@section Readline vi Mode
1464
1465While the Readline library does not have a full set of @code{vi}
1466editing functions, it does contain enough to allow simple editing
1467of the line. The Readline @code{vi} mode behaves as specified in
1468the @sc{posix} 1003.2 standard.
1469
1470@ifset BashFeatures
1471In order to switch interactively between @code{emacs} and @code{vi}
1472editing modes, use the @samp{set -o emacs} and @samp{set -o vi}
1473commands (@pxref{The Set Builtin}).
1474@end ifset
1475@ifclear BashFeatures
1476In order to switch interactively between @code{emacs} and @code{vi}
1477editing modes, use the command @kbd{M-C-j} (bound to emacs-editing-mode
1478when in @code{vi} mode and to vi-editing-mode in @code{emacs} mode).
1479@end ifclear
1480The Readline default is @code{emacs} mode.
1481
1482When you enter a line in @code{vi} mode, you are already placed in
1483`insertion' mode, as if you had typed an @samp{i}. Pressing @key{ESC}
1484switches you into `command' mode, where you can edit the text of the
1485line with the standard @code{vi} movement keys, move to previous
1486history lines with @samp{k} and subsequent lines with @samp{j}, and
1487so forth.
1488
1489@ifset BashFeatures
1490@node Programmable Completion
1491@section Programmable Completion
1492@cindex programmable completion
1493
1494When word completion is attempted for an argument to a command for
1495which a completion specification (a @var{compspec}) has been defined
1496using the @code{complete} builtin (@pxref{Programmable Completion Builtins}),
1497the programmable completion facilities are invoked.
1498
1499First, the command name is identified.
1500If a compspec has been defined for that command, the
1501compspec is used to generate the list of possible completions for the word.
1502If the command word is a full pathname, a compspec for the full
1503pathname is searched for first.
1504If no compspec is found for the full pathname, an attempt is made to
1505find a compspec for the portion following the final slash.
1506
1507Once a compspec has been found, it is used to generate the list of
1508matching words.
1509If a compspec is not found, the default Bash completion
1510described above (@pxref{Commands For Completion}) is performed.
1511
1512First, the actions specified by the compspec are used.
1513Only matches which are prefixed by the word being completed are
1514returned.
1515When the @option{-f} or @option{-d} option is used for filename or
1516directory name completion, the shell variable @env{FIGNORE} is
1517used to filter the matches.
1518@xref{Bash Variables}, for a description of @env{FIGNORE}.
1519
1520Any completions specified by a filename expansion pattern to the
1521@option{-G} option are generated next.
1522The words generated by the pattern need not match the word being completed.
1523The @env{GLOBIGNORE} shell variable is not used to filter the matches,
1524but the @env{FIGNORE} shell variable is used.
1525
1526Next, the string specified as the argument to the @option{-W} option
1527is considered.
1528The string is first split using the characters in the @env{IFS}
1529special variable as delimiters.
1530Shell quoting is honored.
1531Each word is then expanded using
1532brace expansion, tilde expansion, parameter and variable expansion,
1533command substitution, arithmetic expansion, and pathname expansion,
1534as described above (@pxref{Shell Expansions}).
1535The results are split using the rules described above
1536(@pxref{Word Splitting}).
1537The results of the expansion are prefix-matched against the word being
1538completed, and the matching words become the possible completions.
1539
1540After these matches have been generated, any shell function or command
1541specified with the @option{-F} and @option{-C} options is invoked.
1542When the command or function is invoked, the @env{COMP_LINE} and
1543@env{COMP_POINT} variables are assigned values as described above
1544(@pxref{Bash Variables}).
1545If a shell function is being invoked, the @env{COMP_WORDS} and
1546@env{COMP_CWORD} variables are also set.
1547When the function or command is invoked, the first argument is the
1548name of the command whose arguments are being completed, the
1549second argument is the word being completed, and the third argument
1550is the word preceding the word being completed on the current command line.
1551No filtering of the generated completions against the word being completed
1552is performed; the function or command has complete freedom in generating
1553the matches.
1554
1555Any function specified with @option{-F} is invoked first.
1556The function may use any of the shell facilities, including the
1557@code{compgen} builtin described below
1558(@pxref{Programmable Completion Builtins}), to generate the matches.
1559It must put the possible completions in the @env{COMPREPLY} array
1560variable.
1561
1562Next, any command specified with the @option{-C} option is invoked
1563in an environment equivalent to command substitution.
1564It should print a list of completions, one per line, to
1565the standard output.
1566Backslash may be used to escape a newline, if necessary.
1567
1568After all of the possible completions are generated, any filter
1569specified with the @option{-X} option is applied to the list.
1570The filter is a pattern as used for pathname expansion; a @samp{&}
1571in the pattern is replaced with the text of the word being completed.
1572A literal @samp{&} may be escaped with a backslash; the backslash
1573is removed before attempting a match.
1574Any completion that matches the pattern will be removed from the list.
1575A leading @samp{!} negates the pattern; in this case any completion
1576not matching the pattern will be removed.
1577
1578Finally, any prefix and suffix specified with the @option{-P} and @option{-S}
1579options are added to each member of the completion list, and the result is
1580returned to the Readline completion code as the list of possible
1581completions.
1582
1583If the previously-applied actions do not generate any matches, and the
1584@option{-o dirnames} option was supplied to @code{complete} when the
1585compspec was defined, directory name completion is attempted.
1586
1587If the @option{-o plusdirs} option was supplied to @code{complete} when
1588the compspec was defined, directory name completion is attempted and any
1589matches are added to the results of the other actions.
1590
1591By default, if a compspec is found, whatever it generates is returned to
1592the completion code as the full set of possible completions.
1593The default Bash completions are not attempted, and the Readline default
1594of filename completion is disabled.
1595If the @option{-o bashdefault} option was supplied to @code{complete} when
1596the compspec was defined, the default Bash completions are attempted
1597if the compspec generates no matches.
1598If the @option{-o default} option was supplied to @code{complete} when the
1599compspec was defined, Readline's default completion will be performed
1600if the compspec (and, if attempted, the default Bash completions)
1601generate no matches.
1602
1603When a compspec indicates that directory name completion is desired,
1604the programmable completion functions force Readline to append a slash
1605to completed names which are symbolic links to directories, subject to
1606the value of the @var{mark-directories} Readline variable, regardless
1607of the setting of the @var{mark-symlinked-directories} Readline variable.
1608
1609@node Programmable Completion Builtins
1610@section Programmable Completion Builtins
1611@cindex completion builtins
1612
1613Two builtin commands are available to manipulate the programmable completion
1614facilities.
1615
1616@table @code
1617@item compgen
1618@btindex compgen
1619@example
1620@code{compgen [@var{option}] [@var{word}]}
1621@end example
1622
1623Generate possible completion matches for @var{word} according to
1624the @var{option}s, which may be any option accepted by the
1625@code{complete}
1626builtin with the exception of @option{-p} and @option{-r}, and write
1627the matches to the standard output.
1628When using the @option{-F} or @option{-C} options, the various shell variables
1629set by the programmable completion facilities, while available, will not
1630have useful values.
1631
1632The matches will be generated in the same way as if the programmable
1633completion code had generated them directly from a completion specification
1634with the same flags.
1635If @var{word} is specified, only those completions matching @var{word}
1636will be displayed.
1637
1638The return value is true unless an invalid option is supplied, or no
1639matches were generated.
1640
1641@item complete
1642@btindex complete
1643@example
1644@code{complete [-abcdefgjksuv] [-o @var{comp-option}] [-A @var{action}] [-G @var{globpat}] [-W @var{wordlist}]
1645[-P @var{prefix}] [-S @var{suffix}] [-X @var{filterpat}] [-F @var{function}]
1646[-C @var{command}] @var{name} [@var{name} @dots{}]}
1647@code{complete -pr [@var{name} @dots{}]}
1648@end example
1649
1650Specify how arguments to each @var{name} should be completed.
1651If the @option{-p} option is supplied, or if no options are supplied, existing
1652completion specifications are printed in a way that allows them to be
1653reused as input.
1654The @option{-r} option removes a completion specification for
1655each @var{name}, or, if no @var{name}s are supplied, all
1656completion specifications.
1657
1658The process of applying these completion specifications when word completion
1659is attempted is described above (@pxref{Programmable Completion}).
1660
1661Other options, if specified, have the following meanings.
1662The arguments to the @option{-G}, @option{-W}, and @option{-X} options
1663(and, if necessary, the @option{-P} and @option{-S} options)
1664should be quoted to protect them from expansion before the
1665@code{complete} builtin is invoked.
1666
1667
1668@table @code
1669@item -o @var{comp-option}
1670The @var{comp-option} controls several aspects of the compspec's behavior
1671beyond the simple generation of completions.
1672@var{comp-option} may be one of:
1673
1674@table @code
1675
1676@item bashdefault
1677Perform the rest of the default Bash completions if the compspec
1678generates no matches.
1679
1680@item default
1681Use Readline's default filename completion if the compspec generates
1682no matches.
1683
1684@item dirnames
1685Perform directory name completion if the compspec generates no matches.
1686
1687@item filenames
1688Tell Readline that the compspec generates filenames, so it can perform any
1689filename-specific processing (like adding a slash to directory names or
1690suppressing trailing spaces). This option is intended to be used with
1691shell functions specified with @option{-F}.
1692
1693@item nospace
1694Tell Readline not to append a space (the default) to words completed at
1695the end of the line.
1696@end table
1697
1698@item -A @var{action}
1699The @var{action} may be one of the following to generate a list of possible
1700completions:
1701
1702@table @code
1703@item alias
1704Alias names. May also be specified as @option{-a}.
1705
1706@item arrayvar
1707Array variable names.
1708
1709@item binding
1710Readline key binding names (@pxref{Bindable Readline Commands}).
1711
1712@item builtin
1713Names of shell builtin commands. May also be specified as @option{-b}.
1714
1715@item command
1716Command names. May also be specified as @option{-c}.
1717
1718@item directory
1719Directory names. May also be specified as @option{-d}.
1720
1721@item disabled
1722Names of disabled shell builtins.
1723
1724@item enabled
1725Names of enabled shell builtins.
1726
1727@item export
1728Names of exported shell variables. May also be specified as @option{-e}.
1729
1730@item file
1731File names. May also be specified as @option{-f}.
1732
1733@item function
1734Names of shell functions.
1735
1736@item group
1737Group names. May also be specified as @option{-g}.
1738
1739@item helptopic
1740Help topics as accepted by the @code{help} builtin (@pxref{Bash Builtins}).
1741
1742@item hostname
1743Hostnames, as taken from the file specified by the
1744@env{HOSTFILE} shell variable (@pxref{Bash Variables}).
1745
1746@item job
1747Job names, if job control is active. May also be specified as @option{-j}.
1748
1749@item keyword
1750Shell reserved words. May also be specified as @option{-k}.
1751
1752@item running
1753Names of running jobs, if job control is active.
1754
1755@item service
1756Service names. May also be specified as @option{-s}.
1757
1758@item setopt
1759Valid arguments for the @option{-o} option to the @code{set} builtin
1760(@pxref{The Set Builtin}).
1761
1762@item shopt
1763Shell option names as accepted by the @code{shopt} builtin
1764(@pxref{Bash Builtins}).
1765
1766@item signal
1767Signal names.
1768
1769@item stopped
1770Names of stopped jobs, if job control is active.
1771
1772@item user
1773User names. May also be specified as @option{-u}.
1774
1775@item variable
1776Names of all shell variables. May also be specified as @option{-v}.
1777@end table
1778
1779@item -G @var{globpat}
1780The filename expansion pattern @var{globpat} is expanded to generate
1781the possible completions.
1782
1783@item -W @var{wordlist}
1784The @var{wordlist} is split using the characters in the
1785@env{IFS} special variable as delimiters, and each resultant word
1786is expanded.
1787The possible completions are the members of the resultant list which
1788match the word being completed.
1789
1790@item -C @var{command}
1791@var{command} is executed in a subshell environment, and its output is
1792used as the possible completions.
1793
1794@item -F @var{function}
1795The shell function @var{function} is executed in the current shell
1796environment.
1797When it finishes, the possible completions are retrieved from the value
1798of the @env{COMPREPLY} array variable.
1799
1800@item -X @var{filterpat}
1801@var{filterpat} is a pattern as used for filename expansion.
1802It is applied to the list of possible completions generated by the
1803preceding options and arguments, and each completion matching
1804@var{filterpat} is removed from the list.
1805A leading @samp{!} in @var{filterpat} negates the pattern; in this
1806case, any completion not matching @var{filterpat} is removed.
1807
1808@item -P @var{prefix}
1809@var{prefix} is added at the beginning of each possible completion
1810after all other options have been applied.
1811
1812@item -S @var{suffix}
1813@var{suffix} is appended to each possible completion
1814after all other options have been applied.
1815@end table
1816
1817The return value is true unless an invalid option is supplied, an option
1818other than @option{-p} or @option{-r} is supplied without a @var{name}
1819argument, an attempt is made to remove a completion specification for
1820a @var{name} for which no specification exists, or
1821an error occurs adding a completion specification.
1822
1823@end table
1824@end ifset
2@setfilename rluser.info
3@comment %**end of header (This is for running Texinfo on a region.)
4@setchapternewpage odd
5
6@ignore
7This file documents the end user interface to the GNU command line
8editing features. It is to be an appendix to manuals for programs which
9use these features. There is a document entitled "readline.texinfo"
10which contains both end-user and programmer documentation for the
11GNU Readline Library.
12
13Copyright (C) 1988-2004 Free Software Foundation, Inc.
14
15Authored by Brian Fox and Chet Ramey.
16
17Permission is granted to process this file through Tex and print the
18results, provided the printed document carries copying permission notice
19identical to this one except for the removal of this paragraph (this
20paragraph not being relevant to the printed manual).
21
22Permission is granted to make and distribute verbatim copies of this manual
23provided the copyright notice and this permission notice are preserved on
24all copies.
25
26Permission is granted to copy and distribute modified versions of this
27manual under the conditions for verbatim copying, provided also that the
28GNU Copyright statement is available to the distributee, and provided that
29the entire resulting derived work is distributed under the terms of a
30permission notice identical to this one.
31
32Permission is granted to copy and distribute translations of this manual
33into another language, under the above conditions for modified versions.
34@end ignore
35
36@comment If you are including this manual as an appendix, then set the
37@comment variable readline-appendix.
38
39@ifclear BashFeatures
40@defcodeindex bt
41@end ifclear
42
43@node Command Line Editing
44@chapter Command Line Editing
45
46This chapter describes the basic features of the @sc{gnu}
47command line editing interface.
48@ifset BashFeatures
49Command line editing is provided by the Readline library, which is
50used by several different programs, including Bash.
51@end ifset
52
53@menu
54* Introduction and Notation:: Notation used in this text.
55* Readline Interaction:: The minimum set of commands for editing a line.
56* Readline Init File:: Customizing Readline from a user's view.
57* Bindable Readline Commands:: A description of most of the Readline commands
58 available for binding
59* Readline vi Mode:: A short description of how to make Readline
60 behave like the vi editor.
61@ifset BashFeatures
62* Programmable Completion:: How to specify the possible completions for
63 a specific command.
64* Programmable Completion Builtins:: Builtin commands to specify how to
65 complete arguments for a particular command.
66@end ifset
67@end menu
68
69@node Introduction and Notation
70@section Introduction to Line Editing
71
72The following paragraphs describe the notation used to represent
73keystrokes.
74
75The text @kbd{C-k} is read as `Control-K' and describes the character
76produced when the @key{k} key is pressed while the Control key
77is depressed.
78
79The text @kbd{M-k} is read as `Meta-K' and describes the character
80produced when the Meta key (if you have one) is depressed, and the @key{k}
81key is pressed.
82The Meta key is labeled @key{ALT} on many keyboards.
83On keyboards with two keys labeled @key{ALT} (usually to either side of
84the space bar), the @key{ALT} on the left side is generally set to
85work as a Meta key.
86The @key{ALT} key on the right may also be configured to work as a
87Meta key or may be configured as some other modifier, such as a
88Compose key for typing accented characters.
89
90If you do not have a Meta or @key{ALT} key, or another key working as
91a Meta key, the identical keystroke can be generated by typing @key{ESC}
92@emph{first}, and then typing @key{k}.
93Either process is known as @dfn{metafying} the @key{k} key.
94
95The text @kbd{M-C-k} is read as `Meta-Control-k' and describes the
96character produced by @dfn{metafying} @kbd{C-k}.
97
98In addition, several keys have their own names. Specifically,
99@key{DEL}, @key{ESC}, @key{LFD}, @key{SPC}, @key{RET}, and @key{TAB} all
100stand for themselves when seen in this text, or in an init file
101(@pxref{Readline Init File}).
102If your keyboard lacks a @key{LFD} key, typing @key{C-j} will
103produce the desired character.
104The @key{RET} key may be labeled @key{Return} or @key{Enter} on
105some keyboards.
106
107@node Readline Interaction
108@section Readline Interaction
109@cindex interaction, readline
110
111Often during an interactive session you type in a long line of text,
112only to notice that the first word on the line is misspelled. The
113Readline library gives you a set of commands for manipulating the text
114as you type it in, allowing you to just fix your typo, and not forcing
115you to retype the majority of the line. Using these editing commands,
116you move the cursor to the place that needs correction, and delete or
117insert the text of the corrections. Then, when you are satisfied with
118the line, you simply press @key{RET}. You do not have to be at the
119end of the line to press @key{RET}; the entire line is accepted
120regardless of the location of the cursor within the line.
121
122@menu
123* Readline Bare Essentials:: The least you need to know about Readline.
124* Readline Movement Commands:: Moving about the input line.
125* Readline Killing Commands:: How to delete text, and how to get it back!
126* Readline Arguments:: Giving numeric arguments to commands.
127* Searching:: Searching through previous lines.
128@end menu
129
130@node Readline Bare Essentials
131@subsection Readline Bare Essentials
132@cindex notation, readline
133@cindex command editing
134@cindex editing command lines
135
136In order to enter characters into the line, simply type them. The typed
137character appears where the cursor was, and then the cursor moves one
138space to the right. If you mistype a character, you can use your
139erase character to back up and delete the mistyped character.
140
141Sometimes you may mistype a character, and
142not notice the error until you have typed several other characters. In
143that case, you can type @kbd{C-b} to move the cursor to the left, and then
144correct your mistake. Afterwards, you can move the cursor to the right
145with @kbd{C-f}.
146
147When you add text in the middle of a line, you will notice that characters
148to the right of the cursor are `pushed over' to make room for the text
149that you have inserted. Likewise, when you delete text behind the cursor,
150characters to the right of the cursor are `pulled back' to fill in the
151blank space created by the removal of the text. A list of the bare
152essentials for editing the text of an input line follows.
153
154@table @asis
155@item @kbd{C-b}
156Move back one character.
157@item @kbd{C-f}
158Move forward one character.
159@item @key{DEL} or @key{Backspace}
160Delete the character to the left of the cursor.
161@item @kbd{C-d}
162Delete the character underneath the cursor.
163@item @w{Printing characters}
164Insert the character into the line at the cursor.
165@item @kbd{C-_} or @kbd{C-x C-u}
166Undo the last editing command. You can undo all the way back to an
167empty line.
168@end table
169
170@noindent
171(Depending on your configuration, the @key{Backspace} key be set to
172delete the character to the left of the cursor and the @key{DEL} key set
173to delete the character underneath the cursor, like @kbd{C-d}, rather
174than the character to the left of the cursor.)
175
176@node Readline Movement Commands
177@subsection Readline Movement Commands
178
179
180The above table describes the most basic keystrokes that you need
181in order to do editing of the input line. For your convenience, many
182other commands have been added in addition to @kbd{C-b}, @kbd{C-f},
183@kbd{C-d}, and @key{DEL}. Here are some commands for moving more rapidly
184about the line.
185
186@table @kbd
187@item C-a
188Move to the start of the line.
189@item C-e
190Move to the end of the line.
191@item M-f
192Move forward a word, where a word is composed of letters and digits.
193@item M-b
194Move backward a word.
195@item C-l
196Clear the screen, reprinting the current line at the top.
197@end table
198
199Notice how @kbd{C-f} moves forward a character, while @kbd{M-f} moves
200forward a word. It is a loose convention that control keystrokes
201operate on characters while meta keystrokes operate on words.
202
203@node Readline Killing Commands
204@subsection Readline Killing Commands
205
206@cindex killing text
207@cindex yanking text
208
209@dfn{Killing} text means to delete the text from the line, but to save
210it away for later use, usually by @dfn{yanking} (re-inserting)
211it back into the line.
212(`Cut' and `paste' are more recent jargon for `kill' and `yank'.)
213
214If the description for a command says that it `kills' text, then you can
215be sure that you can get the text back in a different (or the same)
216place later.
217
218When you use a kill command, the text is saved in a @dfn{kill-ring}.
219Any number of consecutive kills save all of the killed text together, so
220that when you yank it back, you get it all. The kill
221ring is not line specific; the text that you killed on a previously
222typed line is available to be yanked back later, when you are typing
223another line.
224@cindex kill ring
225
226Here is the list of commands for killing text.
227
228@table @kbd
229@item C-k
230Kill the text from the current cursor position to the end of the line.
231
232@item M-d
233Kill from the cursor to the end of the current word, or, if between
234words, to the end of the next word.
235Word boundaries are the same as those used by @kbd{M-f}.
236
237@item M-@key{DEL}
238Kill from the cursor the start of the current word, or, if between
239words, to the start of the previous word.
240Word boundaries are the same as those used by @kbd{M-b}.
241
242@item C-w
243Kill from the cursor to the previous whitespace. This is different than
244@kbd{M-@key{DEL}} because the word boundaries differ.
245
246@end table
247
248Here is how to @dfn{yank} the text back into the line. Yanking
249means to copy the most-recently-killed text from the kill buffer.
250
251@table @kbd
252@item C-y
253Yank the most recently killed text back into the buffer at the cursor.
254
255@item M-y
256Rotate the kill-ring, and yank the new top. You can only do this if
257the prior command is @kbd{C-y} or @kbd{M-y}.
258@end table
259
260@node Readline Arguments
261@subsection Readline Arguments
262
263You can pass numeric arguments to Readline commands. Sometimes the
264argument acts as a repeat count, other times it is the @i{sign} of the
265argument that is significant. If you pass a negative argument to a
266command which normally acts in a forward direction, that command will
267act in a backward direction. For example, to kill text back to the
268start of the line, you might type @samp{M-- C-k}.
269
270The general way to pass numeric arguments to a command is to type meta
271digits before the command. If the first `digit' typed is a minus
272sign (@samp{-}), then the sign of the argument will be negative. Once
273you have typed one meta digit to get the argument started, you can type
274the remainder of the digits, and then the command. For example, to give
275the @kbd{C-d} command an argument of 10, you could type @samp{M-1 0 C-d},
276which will delete the next ten characters on the input line.
277
278@node Searching
279@subsection Searching for Commands in the History
280
281Readline provides commands for searching through the command history
282@ifset BashFeatures
283(@pxref{Bash History Facilities})
284@end ifset
285for lines containing a specified string.
286There are two search modes: @dfn{incremental} and @dfn{non-incremental}.
287
288Incremental searches begin before the user has finished typing the
289search string.
290As each character of the search string is typed, Readline displays
291the next entry from the history matching the string typed so far.
292An incremental search requires only as many characters as needed to
293find the desired history entry.
294To search backward in the history for a particular string, type
295@kbd{C-r}. Typing @kbd{C-s} searches forward through the history.
296The characters present in the value of the @code{isearch-terminators} variable
297are used to terminate an incremental search.
298If that variable has not been assigned a value, the @key{ESC} and
299@kbd{C-J} characters will terminate an incremental search.
300@kbd{C-g} will abort an incremental search and restore the original line.
301When the search is terminated, the history entry containing the
302search string becomes the current line.
303
304To find other matching entries in the history list, type @kbd{C-r} or
305@kbd{C-s} as appropriate.
306This will search backward or forward in the history for the next
307entry matching the search string typed so far.
308Any other key sequence bound to a Readline command will terminate
309the search and execute that command.
310For instance, a @key{RET} will terminate the search and accept
311the line, thereby executing the command from the history list.
312A movement command will terminate the search, make the last line found
313the current line, and begin editing.
314
315Readline remembers the last incremental search string. If two
316@kbd{C-r}s are typed without any intervening characters defining a new
317search string, any remembered search string is used.
318
319Non-incremental searches read the entire search string before starting
320to search for matching history lines. The search string may be
321typed by the user or be part of the contents of the current line.
322
323@node Readline Init File
324@section Readline Init File
325@cindex initialization file, readline
326
327Although the Readline library comes with a set of Emacs-like
328keybindings installed by default, it is possible to use a different set
329of keybindings.
330Any user can customize programs that use Readline by putting
331commands in an @dfn{inputrc} file, conventionally in his home directory.
332The name of this
333@ifset BashFeatures
334file is taken from the value of the shell variable @env{INPUTRC}. If
335@end ifset
336@ifclear BashFeatures
337file is taken from the value of the environment variable @env{INPUTRC}. If
338@end ifclear
339that variable is unset, the default is @file{~/.inputrc}.
340
341When a program which uses the Readline library starts up, the
342init file is read, and the key bindings are set.
343
344In addition, the @code{C-x C-r} command re-reads this init file, thus
345incorporating any changes that you might have made to it.
346
347@menu
348* Readline Init File Syntax:: Syntax for the commands in the inputrc file.
349
350* Conditional Init Constructs:: Conditional key bindings in the inputrc file.
351
352* Sample Init File:: An example inputrc file.
353@end menu
354
355@node Readline Init File Syntax
356@subsection Readline Init File Syntax
357
358There are only a few basic constructs allowed in the
359Readline init file. Blank lines are ignored.
360Lines beginning with a @samp{#} are comments.
361Lines beginning with a @samp{$} indicate conditional
362constructs (@pxref{Conditional Init Constructs}). Other lines
363denote variable settings and key bindings.
364
365@table @asis
366@item Variable Settings
367You can modify the run-time behavior of Readline by
368altering the values of variables in Readline
369using the @code{set} command within the init file.
370The syntax is simple:
371
372@example
373set @var{variable} @var{value}
374@end example
375
376@noindent
377Here, for example, is how to
378change from the default Emacs-like key binding to use
379@code{vi} line editing commands:
380
381@example
382set editing-mode vi
383@end example
384
385Variable names and values, where appropriate, are recognized without regard
386to case.
387
388@ifset BashFeatures
389The @w{@code{bind -V}} command lists the current Readline variable names
390and values. @xref{Bash Builtins}.
391@end ifset
392
393A great deal of run-time behavior is changeable with the following
394variables.
395
396@cindex variables, readline
397@table @code
398
399@item bell-style
400@vindex bell-style
401Controls what happens when Readline wants to ring the terminal bell.
402If set to @samp{none}, Readline never rings the bell. If set to
403@samp{visible}, Readline uses a visible bell if one is available.
404If set to @samp{audible} (the default), Readline attempts to ring
405the terminal's bell.
406
407@item comment-begin
408@vindex comment-begin
409The string to insert at the beginning of the line when the
410@code{insert-comment} command is executed. The default value
411is @code{"#"}.
412
413@item completion-ignore-case
414If set to @samp{on}, Readline performs filename matching and completion
415in a case-insensitive fashion.
416The default value is @samp{off}.
417
418@item completion-query-items
419@vindex completion-query-items
420The number of possible completions that determines when the user is
421asked whether the list of possibilities should be displayed.
422If the number of possible completions is greater than this value,
423Readline will ask the user whether or not he wishes to view
424them; otherwise, they are simply listed.
425This variable must be set to an integer value greater than or equal to 0.
426The default limit is @code{100}.
427
428@item convert-meta
429@vindex convert-meta
430If set to @samp{on}, Readline will convert characters with the
431eighth bit set to an @sc{ascii} key sequence by stripping the eighth
432bit and prefixing an @key{ESC} character, converting them to a
433meta-prefixed key sequence. The default value is @samp{on}.
434
435@item disable-completion
436@vindex disable-completion
437If set to @samp{On}, Readline will inhibit word completion.
438Completion characters will be inserted into the line as if they had
439been mapped to @code{self-insert}. The default is @samp{off}.
440
441@item editing-mode
442@vindex editing-mode
443The @code{editing-mode} variable controls which default set of
444key bindings is used. By default, Readline starts up in Emacs editing
445mode, where the keystrokes are most similar to Emacs. This variable can be
446set to either @samp{emacs} or @samp{vi}.
447
448@item enable-keypad
449@vindex enable-keypad
450When set to @samp{on}, Readline will try to enable the application
451keypad when it is called. Some systems need this to enable the
452arrow keys. The default is @samp{off}.
453
454@item expand-tilde
455@vindex expand-tilde
456If set to @samp{on}, tilde expansion is performed when Readline
457attempts word completion. The default is @samp{off}.
458
459@vindex history-preserve-point
460If set to @samp{on}, the history code attempts to place point at the
461same location on each history line retrieved with @code{previous-history}
462or @code{next-history}.
463
464@item horizontal-scroll-mode
465@vindex horizontal-scroll-mode
466This variable can be set to either @samp{on} or @samp{off}. Setting it
467to @samp{on} means that the text of the lines being edited will scroll
468horizontally on a single screen line when they are longer than the width
469of the screen, instead of wrapping onto a new screen line. By default,
470this variable is set to @samp{off}.
471
472@item input-meta
473@vindex input-meta
474@vindex meta-flag
475If set to @samp{on}, Readline will enable eight-bit input (it
476will not clear the eighth bit in the characters it reads),
477regardless of what the terminal claims it can support. The
478default value is @samp{off}. The name @code{meta-flag} is a
479synonym for this variable.
480
481@item isearch-terminators
482@vindex isearch-terminators
483The string of characters that should terminate an incremental search without
484subsequently executing the character as a command (@pxref{Searching}).
485If this variable has not been given a value, the characters @key{ESC} and
486@kbd{C-J} will terminate an incremental search.
487
488@item keymap
489@vindex keymap
490Sets Readline's idea of the current keymap for key binding commands.
491Acceptable @code{keymap} names are
492@code{emacs},
493@code{emacs-standard},
494@code{emacs-meta},
495@code{emacs-ctlx},
496@code{vi},
497@code{vi-move},
498@code{vi-command}, and
499@code{vi-insert}.
500@code{vi} is equivalent to @code{vi-command}; @code{emacs} is
501equivalent to @code{emacs-standard}. The default value is @code{emacs}.
502The value of the @code{editing-mode} variable also affects the
503default keymap.
504
505@item mark-directories
506If set to @samp{on}, completed directory names have a slash
507appended. The default is @samp{on}.
508
509@item mark-modified-lines
510@vindex mark-modified-lines
511This variable, when set to @samp{on}, causes Readline to display an
512asterisk (@samp{*}) at the start of history lines which have been modified.
513This variable is @samp{off} by default.
514
515@item mark-symlinked-directories
516@vindex mark-symlinked-directories
517If set to @samp{on}, completed names which are symbolic links
518to directories have a slash appended (subject to the value of
519@code{mark-directories}).
520The default is @samp{off}.
521
522@item match-hidden-files
523@vindex match-hidden-files
524This variable, when set to @samp{on}, causes Readline to match files whose
525names begin with a @samp{.} (hidden files) when performing filename
526completion, unless the leading @samp{.} is
527supplied by the user in the filename to be completed.
528This variable is @samp{on} by default.
529
530@item output-meta
531@vindex output-meta
532If set to @samp{on}, Readline will display characters with the
533eighth bit set directly rather than as a meta-prefixed escape
534sequence. The default is @samp{off}.
535
536@item page-completions
537@vindex page-completions
538If set to @samp{on}, Readline uses an internal @code{more}-like pager
539to display a screenful of possible completions at a time.
540This variable is @samp{on} by default.
541
542@item print-completions-horizontally
543If set to @samp{on}, Readline will display completions with matches
544sorted horizontally in alphabetical order, rather than down the screen.
545The default is @samp{off}.
546
547@item show-all-if-ambiguous
548@vindex show-all-if-ambiguous
549This alters the default behavior of the completion functions. If
550set to @samp{on},
551words which have more than one possible completion cause the
552matches to be listed immediately instead of ringing the bell.
553The default value is @samp{off}.
554
555@item show-all-if-unmodified
556@vindex show-all-if-unmodified
557This alters the default behavior of the completion functions in
558a fashion similar to @var{show-all-if-ambiguous}.
559If set to @samp{on},
560words which have more than one possible completion without any
561possible partial completion (the possible completions don't share
562a common prefix) cause the matches to be listed immediately instead
563of ringing the bell.
564The default value is @samp{off}.
565
566@item visible-stats
567@vindex visible-stats
568If set to @samp{on}, a character denoting a file's type
569is appended to the filename when listing possible
570completions. The default is @samp{off}.
571
572@end table
573
574@item Key Bindings
575The syntax for controlling key bindings in the init file is
576simple. First you need to find the name of the command that you
577want to change. The following sections contain tables of the command
578name, the default keybinding, if any, and a short description of what
579the command does.
580
581Once you know the name of the command, simply place on a line
582in the init file the name of the key
583you wish to bind the command to, a colon, and then the name of the
584command. The name of the key
585can be expressed in different ways, depending on what you find most
586comfortable.
587
588In addition to command names, readline allows keys to be bound
589to a string that is inserted when the key is pressed (a @var{macro}).
590
591@ifset BashFeatures
592The @w{@code{bind -p}} command displays Readline function names and
593bindings in a format that can put directly into an initialization file.
594@xref{Bash Builtins}.
595@end ifset
596
597@table @asis
598@item @w{@var{keyname}: @var{function-name} or @var{macro}}
599@var{keyname} is the name of a key spelled out in English. For example:
600@example
601Control-u: universal-argument
602Meta-Rubout: backward-kill-word
603Control-o: "> output"
604@end example
605
606In the above example, @kbd{C-u} is bound to the function
607@code{universal-argument},
608@kbd{M-DEL} is bound to the function @code{backward-kill-word}, and
609@kbd{C-o} is bound to run the macro
610expressed on the right hand side (that is, to insert the text
611@samp{> output} into the line).
612
613A number of symbolic character names are recognized while
614processing this key binding syntax:
615@var{DEL},
616@var{ESC},
617@var{ESCAPE},
618@var{LFD},
619@var{NEWLINE},
620@var{RET},
621@var{RETURN},
622@var{RUBOUT},
623@var{SPACE},
624@var{SPC},
625and
626@var{TAB}.
627
628@item @w{"@var{keyseq}": @var{function-name} or @var{macro}}
629@var{keyseq} differs from @var{keyname} above in that strings
630denoting an entire key sequence can be specified, by placing
631the key sequence in double quotes. Some @sc{gnu} Emacs style key
632escapes can be used, as in the following example, but the
633special character names are not recognized.
634
635@example
636"\C-u": universal-argument
637"\C-x\C-r": re-read-init-file
638"\e[11~": "Function Key 1"
639@end example
640
641In the above example, @kbd{C-u} is again bound to the function
642@code{universal-argument} (just as it was in the first example),
643@samp{@kbd{C-x} @kbd{C-r}} is bound to the function @code{re-read-init-file},
644and @samp{@key{ESC} @key{[} @key{1} @key{1} @key{~}} is bound to insert
645the text @samp{Function Key 1}.
646
647@end table
648
649The following @sc{gnu} Emacs style escape sequences are available when
650specifying key sequences:
651
652@table @code
653@item @kbd{\C-}
654control prefix
655@item @kbd{\M-}
656meta prefix
657@item @kbd{\e}
658an escape character
659@item @kbd{\\}
660backslash
661@item @kbd{\"}
662@key{"}, a double quotation mark
663@item @kbd{\'}
664@key{'}, a single quote or apostrophe
665@end table
666
667In addition to the @sc{gnu} Emacs style escape sequences, a second
668set of backslash escapes is available:
669
670@table @code
671@item \a
672alert (bell)
673@item \b
674backspace
675@item \d
676delete
677@item \f
678form feed
679@item \n
680newline
681@item \r
682carriage return
683@item \t
684horizontal tab
685@item \v
686vertical tab
687@item \@var{nnn}
688the eight-bit character whose value is the octal value @var{nnn}
689(one to three digits)
690@item \x@var{HH}
691the eight-bit character whose value is the hexadecimal value @var{HH}
692(one or two hex digits)
693@end table
694
695When entering the text of a macro, single or double quotes must
696be used to indicate a macro definition.
697Unquoted text is assumed to be a function name.
698In the macro body, the backslash escapes described above are expanded.
699Backslash will quote any other character in the macro text,
700including @samp{"} and @samp{'}.
701For example, the following binding will make @samp{@kbd{C-x} \}
702insert a single @samp{\} into the line:
703@example
704"\C-x\\": "\\"
705@end example
706
707@end table
708
709@node Conditional Init Constructs
710@subsection Conditional Init Constructs
711
712Readline implements a facility similar in spirit to the conditional
713compilation features of the C preprocessor which allows key
714bindings and variable settings to be performed as the result
715of tests. There are four parser directives used.
716
717@table @code
718@item $if
719The @code{$if} construct allows bindings to be made based on the
720editing mode, the terminal being used, or the application using
721Readline. The text of the test extends to the end of the line;
722no characters are required to isolate it.
723
724@table @code
725@item mode
726The @code{mode=} form of the @code{$if} directive is used to test
727whether Readline is in @code{emacs} or @code{vi} mode.
728This may be used in conjunction
729with the @samp{set keymap} command, for instance, to set bindings in
730the @code{emacs-standard} and @code{emacs-ctlx} keymaps only if
731Readline is starting out in @code{emacs} mode.
732
733@item term
734The @code{term=} form may be used to include terminal-specific
735key bindings, perhaps to bind the key sequences output by the
736terminal's function keys. The word on the right side of the
737@samp{=} is tested against both the full name of the terminal and
738the portion of the terminal name before the first @samp{-}. This
739allows @code{sun} to match both @code{sun} and @code{sun-cmd},
740for instance.
741
742@item application
743The @var{application} construct is used to include
744application-specific settings. Each program using the Readline
745library sets the @var{application name}, and you can test for
746a particular value.
747This could be used to bind key sequences to functions useful for
748a specific program. For instance, the following command adds a
749key sequence that quotes the current or previous word in Bash:
750@example
751$if Bash
752# Quote the current or previous word
753"\C-xq": "\eb\"\ef\""
754$endif
755@end example
756@end table
757
758@item $endif
759This command, as seen in the previous example, terminates an
760@code{$if} command.
761
762@item $else
763Commands in this branch of the @code{$if} directive are executed if
764the test fails.
765
766@item $include
767This directive takes a single filename as an argument and reads commands
768and bindings from that file.
769For example, the following directive reads from @file{/etc/inputrc}:
770@example
771$include /etc/inputrc
772@end example
773@end table
774
775@node Sample Init File
776@subsection Sample Init File
777
778Here is an example of an @var{inputrc} file. This illustrates key
779binding, variable assignment, and conditional syntax.
780
781@example
782@page
783# This file controls the behaviour of line input editing for
784# programs that use the GNU Readline library. Existing
785# programs include FTP, Bash, and GDB.
786#
787# You can re-read the inputrc file with C-x C-r.
788# Lines beginning with '#' are comments.
789#
790# First, include any systemwide bindings and variable
791# assignments from /etc/Inputrc
792$include /etc/Inputrc
793
794#
795# Set various bindings for emacs mode.
796
797set editing-mode emacs
798
799$if mode=emacs
800
801Meta-Control-h: backward-kill-word Text after the function name is ignored
802
803#
804# Arrow keys in keypad mode
805#
806#"\M-OD": backward-char
807#"\M-OC": forward-char
808#"\M-OA": previous-history
809#"\M-OB": next-history
810#
811# Arrow keys in ANSI mode
812#
813"\M-[D": backward-char
814"\M-[C": forward-char
815"\M-[A": previous-history
816"\M-[B": next-history
817#
818# Arrow keys in 8 bit keypad mode
819#
820#"\M-\C-OD": backward-char
821#"\M-\C-OC": forward-char
822#"\M-\C-OA": previous-history
823#"\M-\C-OB": next-history
824#
825# Arrow keys in 8 bit ANSI mode
826#
827#"\M-\C-[D": backward-char
828#"\M-\C-[C": forward-char
829#"\M-\C-[A": previous-history
830#"\M-\C-[B": next-history
831
832C-q: quoted-insert
833
834$endif
835
836# An old-style binding. This happens to be the default.
837TAB: complete
838
839# Macros that are convenient for shell interaction
840$if Bash
841# edit the path
842"\C-xp": "PATH=$@{PATH@}\e\C-e\C-a\ef\C-f"
843# prepare to type a quoted word --
844# insert open and close double quotes
845# and move to just after the open quote
846"\C-x\"": "\"\"\C-b"
847# insert a backslash (testing backslash escapes
848# in sequences and macros)
849"\C-x\\": "\\"
850# Quote the current or previous word
851"\C-xq": "\eb\"\ef\""
852# Add a binding to refresh the line, which is unbound
853"\C-xr": redraw-current-line
854# Edit variable on current line.
855"\M-\C-v": "\C-a\C-k$\C-y\M-\C-e\C-a\C-y="
856$endif
857
858# use a visible bell if one is available
859set bell-style visible
860
861# don't strip characters to 7 bits when reading
862set input-meta on
863
864# allow iso-latin1 characters to be inserted rather
865# than converted to prefix-meta sequences
866set convert-meta off
867
868# display characters with the eighth bit set directly
869# rather than as meta-prefixed characters
870set output-meta on
871
872# if there are more than 150 possible completions for
873# a word, ask the user if he wants to see all of them
874set completion-query-items 150
875
876# For FTP
877$if Ftp
878"\C-xg": "get \M-?"
879"\C-xt": "put \M-?"
880"\M-.": yank-last-arg
881$endif
882@end example
883
884@node Bindable Readline Commands
885@section Bindable Readline Commands
886
887@menu
888* Commands For Moving:: Moving about the line.
889* Commands For History:: Getting at previous lines.
890* Commands For Text:: Commands for changing text.
891* Commands For Killing:: Commands for killing and yanking.
892* Numeric Arguments:: Specifying numeric arguments, repeat counts.
893* Commands For Completion:: Getting Readline to do the typing for you.
894* Keyboard Macros:: Saving and re-executing typed characters
895* Miscellaneous Commands:: Other miscellaneous commands.
896@end menu
897
898This section describes Readline commands that may be bound to key
899sequences.
900@ifset BashFeatures
901You can list your key bindings by executing
902@w{@code{bind -P}} or, for a more terse format, suitable for an
903@var{inputrc} file, @w{@code{bind -p}}. (@xref{Bash Builtins}.)
904@end ifset
905Command names without an accompanying key sequence are unbound by default.
906
907In the following descriptions, @dfn{point} refers to the current cursor
908position, and @dfn{mark} refers to a cursor position saved by the
909@code{set-mark} command.
910The text between the point and mark is referred to as the @dfn{region}.
911
912@node Commands For Moving
913@subsection Commands For Moving
914@ftable @code
915@item beginning-of-line (C-a)
916Move to the start of the current line.
917
918@item end-of-line (C-e)
919Move to the end of the line.
920
921@item forward-char (C-f)
922Move forward a character.
923
924@item backward-char (C-b)
925Move back a character.
926
927@item forward-word (M-f)
928Move forward to the end of the next word. Words are composed of
929letters and digits.
930
931@item backward-word (M-b)
932Move back to the start of the current or previous word. Words are
933composed of letters and digits.
934
935@item clear-screen (C-l)
936Clear the screen and redraw the current line,
937leaving the current line at the top of the screen.
938
939@item redraw-current-line ()
940Refresh the current line. By default, this is unbound.
941
942@end ftable
943
944@node Commands For History
945@subsection Commands For Manipulating The History
946
947@ftable @code
948@item accept-line (Newline or Return)
949@ifset BashFeatures
950Accept the line regardless of where the cursor is.
951If this line is
952non-empty, add it to the history list according to the setting of
953the @env{HISTCONTROL} and @env{HISTIGNORE} variables.
954If this line is a modified history line, then restore the history line
955to its original state.
956@end ifset
957@ifclear BashFeatures
958Accept the line regardless of where the cursor is.
959If this line is
960non-empty, it may be added to the history list for future recall with
961@code{add_history()}.
962If this line is a modified history line, the history line is restored
963to its original state.
964@end ifclear
965
966@item previous-history (C-p)
967Move `back' through the history list, fetching the previous command.
968
969@item next-history (C-n)
970Move `forward' through the history list, fetching the next command.
971
972@item beginning-of-history (M-<)
973Move to the first line in the history.
974
975@item end-of-history (M->)
976Move to the end of the input history, i.e., the line currently
977being entered.
978
979@item reverse-search-history (C-r)
980Search backward starting at the current line and moving `up' through
981the history as necessary. This is an incremental search.
982
983@item forward-search-history (C-s)
984Search forward starting at the current line and moving `down' through
985the the history as necessary. This is an incremental search.
986
987@item non-incremental-reverse-search-history (M-p)
988Search backward starting at the current line and moving `up'
989through the history as necessary using a non-incremental search
990for a string supplied by the user.
991
992@item non-incremental-forward-search-history (M-n)
993Search forward starting at the current line and moving `down'
994through the the history as necessary using a non-incremental search
995for a string supplied by the user.
996
997@item history-search-forward ()
998Search forward through the history for the string of characters
999between the start of the current line and the point.
1000This is a non-incremental search.
1001By default, this command is unbound.
1002
1003@item history-search-backward ()
1004Search backward through the history for the string of characters
1005between the start of the current line and the point. This
1006is a non-incremental search. By default, this command is unbound.
1007
1008@item yank-nth-arg (M-C-y)
1009Insert the first argument to the previous command (usually
1010the second word on the previous line) at point.
1011With an argument @var{n},
1012insert the @var{n}th word from the previous command (the words
1013in the previous command begin with word 0). A negative argument
1014inserts the @var{n}th word from the end of the previous command.
1015
1016@item yank-last-arg (M-. or M-_)
1017Insert last argument to the previous command (the last word of the
1018previous history entry). With an
1019argument, behave exactly like @code{yank-nth-arg}.
1020Successive calls to @code{yank-last-arg} move back through the history
1021list, inserting the last argument of each line in turn.
1022
1023@end ftable
1024
1025@node Commands For Text
1026@subsection Commands For Changing Text
1027
1028@ftable @code
1029@item delete-char (C-d)
1030Delete the character at point. If point is at the
1031beginning of the line, there are no characters in the line, and
1032the last character typed was not bound to @code{delete-char}, then
1033return @sc{eof}.
1034
1035@item backward-delete-char (Rubout)
1036Delete the character behind the cursor. A numeric argument means
1037to kill the characters instead of deleting them.
1038
1039@item forward-backward-delete-char ()
1040Delete the character under the cursor, unless the cursor is at the
1041end of the line, in which case the character behind the cursor is
1042deleted. By default, this is not bound to a key.
1043
1044@item quoted-insert (C-q or C-v)
1045Add the next character typed to the line verbatim. This is
1046how to insert key sequences like @kbd{C-q}, for example.
1047
1048@ifclear BashFeatures
1049@item tab-insert (M-@key{TAB})
1050Insert a tab character.
1051@end ifclear
1052
1053@item self-insert (a, b, A, 1, !, @dots{})
1054Insert yourself.
1055
1056@item transpose-chars (C-t)
1057Drag the character before the cursor forward over
1058the character at the cursor, moving the
1059cursor forward as well. If the insertion point
1060is at the end of the line, then this
1061transposes the last two characters of the line.
1062Negative arguments have no effect.
1063
1064@item transpose-words (M-t)
1065Drag the word before point past the word after point,
1066moving point past that word as well.
1067If the insertion point is at the end of the line, this transposes
1068the last two words on the line.
1069
1070@item upcase-word (M-u)
1071Uppercase the current (or following) word. With a negative argument,
1072uppercase the previous word, but do not move the cursor.
1073
1074@item downcase-word (M-l)
1075Lowercase the current (or following) word. With a negative argument,
1076lowercase the previous word, but do not move the cursor.
1077
1078@item capitalize-word (M-c)
1079Capitalize the current (or following) word. With a negative argument,
1080capitalize the previous word, but do not move the cursor.
1081
1082@item overwrite-mode ()
1083Toggle overwrite mode. With an explicit positive numeric argument,
1084switches to overwrite mode. With an explicit non-positive numeric
1085argument, switches to insert mode. This command affects only
1086@code{emacs} mode; @code{vi} mode does overwrite differently.
1087Each call to @code{readline()} starts in insert mode.
1088
1089In overwrite mode, characters bound to @code{self-insert} replace
1090the text at point rather than pushing the text to the right.
1091Characters bound to @code{backward-delete-char} replace the character
1092before point with a space.
1093
1094By default, this command is unbound.
1095
1096@end ftable
1097
1098@node Commands For Killing
1099@subsection Killing And Yanking
1100
1101@ftable @code
1102
1103@item kill-line (C-k)
1104Kill the text from point to the end of the line.
1105
1106@item backward-kill-line (C-x Rubout)
1107Kill backward to the beginning of the line.
1108
1109@item unix-line-discard (C-u)
1110Kill backward from the cursor to the beginning of the current line.
1111
1112@item kill-whole-line ()
1113Kill all characters on the current line, no matter where point is.
1114By default, this is unbound.
1115
1116@item kill-word (M-d)
1117Kill from point to the end of the current word, or if between
1118words, to the end of the next word.
1119Word boundaries are the same as @code{forward-word}.
1120
1121@item backward-kill-word (M-@key{DEL})
1122Kill the word behind point.
1123Word boundaries are the same as @code{backward-word}.
1124
1125@item unix-word-rubout (C-w)
1126Kill the word behind point, using white space as a word boundary.
1127The killed text is saved on the kill-ring.
1128
1129@item unix-filename-rubout ()
1130Kill the word behind point, using white space and the slash character
1131as the word boundaries.
1132The killed text is saved on the kill-ring.
1133
1134@item delete-horizontal-space ()
1135Delete all spaces and tabs around point. By default, this is unbound.
1136
1137@item kill-region ()
1138Kill the text in the current region.
1139By default, this command is unbound.
1140
1141@item copy-region-as-kill ()
1142Copy the text in the region to the kill buffer, so it can be yanked
1143right away. By default, this command is unbound.
1144
1145@item copy-backward-word ()
1146Copy the word before point to the kill buffer.
1147The word boundaries are the same as @code{backward-word}.
1148By default, this command is unbound.
1149
1150@item copy-forward-word ()
1151Copy the word following point to the kill buffer.
1152The word boundaries are the same as @code{forward-word}.
1153By default, this command is unbound.
1154
1155@item yank (C-y)
1156Yank the top of the kill ring into the buffer at point.
1157
1158@item yank-pop (M-y)
1159Rotate the kill-ring, and yank the new top. You can only do this if
1160the prior command is @code{yank} or @code{yank-pop}.
1161@end ftable
1162
1163@node Numeric Arguments
1164@subsection Specifying Numeric Arguments
1165@ftable @code
1166
1167@item digit-argument (@kbd{M-0}, @kbd{M-1}, @dots{} @kbd{M--})
1168Add this digit to the argument already accumulating, or start a new
1169argument. @kbd{M--} starts a negative argument.
1170
1171@item universal-argument ()
1172This is another way to specify an argument.
1173If this command is followed by one or more digits, optionally with a
1174leading minus sign, those digits define the argument.
1175If the command is followed by digits, executing @code{universal-argument}
1176again ends the numeric argument, but is otherwise ignored.
1177As a special case, if this command is immediately followed by a
1178character that is neither a digit or minus sign, the argument count
1179for the next command is multiplied by four.
1180The argument count is initially one, so executing this function the
1181first time makes the argument count four, a second time makes the
1182argument count sixteen, and so on.
1183By default, this is not bound to a key.
1184@end ftable
1185
1186@node Commands For Completion
1187@subsection Letting Readline Type For You
1188
1189@ftable @code
1190@item complete (@key{TAB})
1191Attempt to perform completion on the text before point.
1192The actual completion performed is application-specific.
1193@ifset BashFeatures
1194Bash attempts completion treating the text as a variable (if the
1195text begins with @samp{$}), username (if the text begins with
1196@samp{~}), hostname (if the text begins with @samp{@@}), or
1197command (including aliases and functions) in turn. If none
1198of these produces a match, filename completion is attempted.
1199@end ifset
1200@ifclear BashFeatures
1201The default is filename completion.
1202@end ifclear
1203
1204@item possible-completions (M-?)
1205List the possible completions of the text before point.
1206
1207@item insert-completions (M-*)
1208Insert all completions of the text before point that would have
1209been generated by @code{possible-completions}.
1210
1211@item menu-complete ()
1212Similar to @code{complete}, but replaces the word to be completed
1213with a single match from the list of possible completions.
1214Repeated execution of @code{menu-complete} steps through the list
1215of possible completions, inserting each match in turn.
1216At the end of the list of completions, the bell is rung
1217(subject to the setting of @code{bell-style})
1218and the original text is restored.
1219An argument of @var{n} moves @var{n} positions forward in the list
1220of matches; a negative argument may be used to move backward
1221through the list.
1222This command is intended to be bound to @key{TAB}, but is unbound
1223by default.
1224
1225@item delete-char-or-list ()
1226Deletes the character under the cursor if not at the beginning or
1227end of the line (like @code{delete-char}).
1228If at the end of the line, behaves identically to
1229@code{possible-completions}.
1230This command is unbound by default.
1231
1232@ifset BashFeatures
1233@item complete-filename (M-/)
1234Attempt filename completion on the text before point.
1235
1236@item possible-filename-completions (C-x /)
1237List the possible completions of the text before point,
1238treating it as a filename.
1239
1240@item complete-username (M-~)
1241Attempt completion on the text before point, treating
1242it as a username.
1243
1244@item possible-username-completions (C-x ~)
1245List the possible completions of the text before point,
1246treating it as a username.
1247
1248@item complete-variable (M-$)
1249Attempt completion on the text before point, treating
1250it as a shell variable.
1251
1252@item possible-variable-completions (C-x $)
1253List the possible completions of the text before point,
1254treating it as a shell variable.
1255
1256@item complete-hostname (M-@@)
1257Attempt completion on the text before point, treating
1258it as a hostname.
1259
1260@item possible-hostname-completions (C-x @@)
1261List the possible completions of the text before point,
1262treating it as a hostname.
1263
1264@item complete-command (M-!)
1265Attempt completion on the text before point, treating
1266it as a command name. Command completion attempts to
1267match the text against aliases, reserved words, shell
1268functions, shell builtins, and finally executable filenames,
1269in that order.
1270
1271@item possible-command-completions (C-x !)
1272List the possible completions of the text before point,
1273treating it as a command name.
1274
1275@item dynamic-complete-history (M-@key{TAB})
1276Attempt completion on the text before point, comparing
1277the text against lines from the history list for possible
1278completion matches.
1279
1280@item complete-into-braces (M-@{)
1281Perform filename completion and insert the list of possible completions
1282enclosed within braces so the list is available to the shell
1283(@pxref{Brace Expansion}).
1284
1285@end ifset
1286@end ftable
1287
1288@node Keyboard Macros
1289@subsection Keyboard Macros
1290@ftable @code
1291
1292@item start-kbd-macro (C-x ()
1293Begin saving the characters typed into the current keyboard macro.
1294
1295@item end-kbd-macro (C-x ))
1296Stop saving the characters typed into the current keyboard macro
1297and save the definition.
1298
1299@item call-last-kbd-macro (C-x e)
1300Re-execute the last keyboard macro defined, by making the characters
1301in the macro appear as if typed at the keyboard.
1302
1303@end ftable
1304
1305@node Miscellaneous Commands
1306@subsection Some Miscellaneous Commands
1307@ftable @code
1308
1309@item re-read-init-file (C-x C-r)
1310Read in the contents of the @var{inputrc} file, and incorporate
1311any bindings or variable assignments found there.
1312
1313@item abort (C-g)
1314Abort the current editing command and
1315ring the terminal's bell (subject to the setting of
1316@code{bell-style}).
1317
1318@item do-uppercase-version (M-a, M-b, M-@var{x}, @dots{})
1319If the metafied character @var{x} is lowercase, run the command
1320that is bound to the corresponding uppercase character.
1321
1322@item prefix-meta (@key{ESC})
1323Metafy the next character typed. This is for keyboards
1324without a meta key. Typing @samp{@key{ESC} f} is equivalent to typing
1325@kbd{M-f}.
1326
1327@item undo (C-_ or C-x C-u)
1328Incremental undo, separately remembered for each line.
1329
1330@item revert-line (M-r)
1331Undo all changes made to this line. This is like executing the @code{undo}
1332command enough times to get back to the beginning.
1333
1334@ifset BashFeatures
1335@item tilde-expand (M-&)
1336@end ifset
1337@ifclear BashFeatures
1338@item tilde-expand (M-~)
1339@end ifclear
1340Perform tilde expansion on the current word.
1341
1342@item set-mark (C-@@)
1343Set the mark to the point. If a
1344numeric argument is supplied, the mark is set to that position.
1345
1346@item exchange-point-and-mark (C-x C-x)
1347Swap the point with the mark. The current cursor position is set to
1348the saved position, and the old cursor position is saved as the mark.
1349
1350@item character-search (C-])
1351A character is read and point is moved to the next occurrence of that
1352character. A negative count searches for previous occurrences.
1353
1354@item character-search-backward (M-C-])
1355A character is read and point is moved to the previous occurrence
1356of that character. A negative count searches for subsequent
1357occurrences.
1358
1359@item insert-comment (M-#)
1360Without a numeric argument, the value of the @code{comment-begin}
1361variable is inserted at the beginning of the current line.
1362If a numeric argument is supplied, this command acts as a toggle: if
1363the characters at the beginning of the line do not match the value
1364of @code{comment-begin}, the value is inserted, otherwise
1365the characters in @code{comment-begin} are deleted from the beginning of
1366the line.
1367In either case, the line is accepted as if a newline had been typed.
1368@ifset BashFeatures
1369The default value of @code{comment-begin} causes this command
1370to make the current line a shell comment.
1371If a numeric argument causes the comment character to be removed, the line
1372will be executed by the shell.
1373@end ifset
1374
1375@item dump-functions ()
1376Print all of the functions and their key bindings to the
1377Readline output stream. If a numeric argument is supplied,
1378the output is formatted in such a way that it can be made part
1379of an @var{inputrc} file. This command is unbound by default.
1380
1381@item dump-variables ()
1382Print all of the settable variables and their values to the
1383Readline output stream. If a numeric argument is supplied,
1384the output is formatted in such a way that it can be made part
1385of an @var{inputrc} file. This command is unbound by default.
1386
1387@item dump-macros ()
1388Print all of the Readline key sequences bound to macros and the
1389strings they output. If a numeric argument is supplied,
1390the output is formatted in such a way that it can be made part
1391of an @var{inputrc} file. This command is unbound by default.
1392
1393@ifset BashFeatures
1394@item glob-complete-word (M-g)
1395The word before point is treated as a pattern for pathname expansion,
1396with an asterisk implicitly appended. This pattern is used to
1397generate a list of matching file names for possible completions.
1398
1399@item glob-expand-word (C-x *)
1400The word before point is treated as a pattern for pathname expansion,
1401and the list of matching file names is inserted, replacing the word.
1402If a numeric argument is supplied, a @samp{*} is appended before
1403pathname expansion.
1404
1405@item glob-list-expansions (C-x g)
1406The list of expansions that would have been generated by
1407@code{glob-expand-word} is displayed, and the line is redrawn.
1408If a numeric argument is supplied, a @samp{*} is appended before
1409pathname expansion.
1410
1411@item display-shell-version (C-x C-v)
1412Display version information about the current instance of Bash.
1413
1414@item shell-expand-line (M-C-e)
1415Expand the line as the shell does.
1416This performs alias and history expansion as well as all of the shell
1417word expansions (@pxref{Shell Expansions}).
1418
1419@item history-expand-line (M-^)
1420Perform history expansion on the current line.
1421
1422@item magic-space ()
1423Perform history expansion on the current line and insert a space
1424(@pxref{History Interaction}).
1425
1426@item alias-expand-line ()
1427Perform alias expansion on the current line (@pxref{Aliases}).
1428
1429@item history-and-alias-expand-line ()
1430Perform history and alias expansion on the current line.
1431
1432@item insert-last-argument (M-. or M-_)
1433A synonym for @code{yank-last-arg}.
1434
1435@item operate-and-get-next (C-o)
1436Accept the current line for execution and fetch the next line
1437relative to the current line from the history for editing. Any
1438argument is ignored.
1439
1440@item edit-and-execute-command (C-xC-e)
1441Invoke an editor on the current command line, and execute the result as shell
1442commands.
1443Bash attempts to invoke
1444@code{$VISUAL}, @code{$EDITOR}, and @code{emacs}
1445as the editor, in that order.
1446
1447@end ifset
1448
1449@ifclear BashFeatures
1450@item emacs-editing-mode (C-e)
1451When in @code{vi} command mode, this causes a switch to @code{emacs}
1452editing mode.
1453
1454@item vi-editing-mode (M-C-j)
1455When in @code{emacs} editing mode, this causes a switch to @code{vi}
1456editing mode.
1457
1458@end ifclear
1459
1460@end ftable
1461
1462@node Readline vi Mode
1463@section Readline vi Mode
1464
1465While the Readline library does not have a full set of @code{vi}
1466editing functions, it does contain enough to allow simple editing
1467of the line. The Readline @code{vi} mode behaves as specified in
1468the @sc{posix} 1003.2 standard.
1469
1470@ifset BashFeatures
1471In order to switch interactively between @code{emacs} and @code{vi}
1472editing modes, use the @samp{set -o emacs} and @samp{set -o vi}
1473commands (@pxref{The Set Builtin}).
1474@end ifset
1475@ifclear BashFeatures
1476In order to switch interactively between @code{emacs} and @code{vi}
1477editing modes, use the command @kbd{M-C-j} (bound to emacs-editing-mode
1478when in @code{vi} mode and to vi-editing-mode in @code{emacs} mode).
1479@end ifclear
1480The Readline default is @code{emacs} mode.
1481
1482When you enter a line in @code{vi} mode, you are already placed in
1483`insertion' mode, as if you had typed an @samp{i}. Pressing @key{ESC}
1484switches you into `command' mode, where you can edit the text of the
1485line with the standard @code{vi} movement keys, move to previous
1486history lines with @samp{k} and subsequent lines with @samp{j}, and
1487so forth.
1488
1489@ifset BashFeatures
1490@node Programmable Completion
1491@section Programmable Completion
1492@cindex programmable completion
1493
1494When word completion is attempted for an argument to a command for
1495which a completion specification (a @var{compspec}) has been defined
1496using the @code{complete} builtin (@pxref{Programmable Completion Builtins}),
1497the programmable completion facilities are invoked.
1498
1499First, the command name is identified.
1500If a compspec has been defined for that command, the
1501compspec is used to generate the list of possible completions for the word.
1502If the command word is a full pathname, a compspec for the full
1503pathname is searched for first.
1504If no compspec is found for the full pathname, an attempt is made to
1505find a compspec for the portion following the final slash.
1506
1507Once a compspec has been found, it is used to generate the list of
1508matching words.
1509If a compspec is not found, the default Bash completion
1510described above (@pxref{Commands For Completion}) is performed.
1511
1512First, the actions specified by the compspec are used.
1513Only matches which are prefixed by the word being completed are
1514returned.
1515When the @option{-f} or @option{-d} option is used for filename or
1516directory name completion, the shell variable @env{FIGNORE} is
1517used to filter the matches.
1518@xref{Bash Variables}, for a description of @env{FIGNORE}.
1519
1520Any completions specified by a filename expansion pattern to the
1521@option{-G} option are generated next.
1522The words generated by the pattern need not match the word being completed.
1523The @env{GLOBIGNORE} shell variable is not used to filter the matches,
1524but the @env{FIGNORE} shell variable is used.
1525
1526Next, the string specified as the argument to the @option{-W} option
1527is considered.
1528The string is first split using the characters in the @env{IFS}
1529special variable as delimiters.
1530Shell quoting is honored.
1531Each word is then expanded using
1532brace expansion, tilde expansion, parameter and variable expansion,
1533command substitution, arithmetic expansion, and pathname expansion,
1534as described above (@pxref{Shell Expansions}).
1535The results are split using the rules described above
1536(@pxref{Word Splitting}).
1537The results of the expansion are prefix-matched against the word being
1538completed, and the matching words become the possible completions.
1539
1540After these matches have been generated, any shell function or command
1541specified with the @option{-F} and @option{-C} options is invoked.
1542When the command or function is invoked, the @env{COMP_LINE} and
1543@env{COMP_POINT} variables are assigned values as described above
1544(@pxref{Bash Variables}).
1545If a shell function is being invoked, the @env{COMP_WORDS} and
1546@env{COMP_CWORD} variables are also set.
1547When the function or command is invoked, the first argument is the
1548name of the command whose arguments are being completed, the
1549second argument is the word being completed, and the third argument
1550is the word preceding the word being completed on the current command line.
1551No filtering of the generated completions against the word being completed
1552is performed; the function or command has complete freedom in generating
1553the matches.
1554
1555Any function specified with @option{-F} is invoked first.
1556The function may use any of the shell facilities, including the
1557@code{compgen} builtin described below
1558(@pxref{Programmable Completion Builtins}), to generate the matches.
1559It must put the possible completions in the @env{COMPREPLY} array
1560variable.
1561
1562Next, any command specified with the @option{-C} option is invoked
1563in an environment equivalent to command substitution.
1564It should print a list of completions, one per line, to
1565the standard output.
1566Backslash may be used to escape a newline, if necessary.
1567
1568After all of the possible completions are generated, any filter
1569specified with the @option{-X} option is applied to the list.
1570The filter is a pattern as used for pathname expansion; a @samp{&}
1571in the pattern is replaced with the text of the word being completed.
1572A literal @samp{&} may be escaped with a backslash; the backslash
1573is removed before attempting a match.
1574Any completion that matches the pattern will be removed from the list.
1575A leading @samp{!} negates the pattern; in this case any completion
1576not matching the pattern will be removed.
1577
1578Finally, any prefix and suffix specified with the @option{-P} and @option{-S}
1579options are added to each member of the completion list, and the result is
1580returned to the Readline completion code as the list of possible
1581completions.
1582
1583If the previously-applied actions do not generate any matches, and the
1584@option{-o dirnames} option was supplied to @code{complete} when the
1585compspec was defined, directory name completion is attempted.
1586
1587If the @option{-o plusdirs} option was supplied to @code{complete} when
1588the compspec was defined, directory name completion is attempted and any
1589matches are added to the results of the other actions.
1590
1591By default, if a compspec is found, whatever it generates is returned to
1592the completion code as the full set of possible completions.
1593The default Bash completions are not attempted, and the Readline default
1594of filename completion is disabled.
1595If the @option{-o bashdefault} option was supplied to @code{complete} when
1596the compspec was defined, the default Bash completions are attempted
1597if the compspec generates no matches.
1598If the @option{-o default} option was supplied to @code{complete} when the
1599compspec was defined, Readline's default completion will be performed
1600if the compspec (and, if attempted, the default Bash completions)
1601generate no matches.
1602
1603When a compspec indicates that directory name completion is desired,
1604the programmable completion functions force Readline to append a slash
1605to completed names which are symbolic links to directories, subject to
1606the value of the @var{mark-directories} Readline variable, regardless
1607of the setting of the @var{mark-symlinked-directories} Readline variable.
1608
1609@node Programmable Completion Builtins
1610@section Programmable Completion Builtins
1611@cindex completion builtins
1612
1613Two builtin commands are available to manipulate the programmable completion
1614facilities.
1615
1616@table @code
1617@item compgen
1618@btindex compgen
1619@example
1620@code{compgen [@var{option}] [@var{word}]}
1621@end example
1622
1623Generate possible completion matches for @var{word} according to
1624the @var{option}s, which may be any option accepted by the
1625@code{complete}
1626builtin with the exception of @option{-p} and @option{-r}, and write
1627the matches to the standard output.
1628When using the @option{-F} or @option{-C} options, the various shell variables
1629set by the programmable completion facilities, while available, will not
1630have useful values.
1631
1632The matches will be generated in the same way as if the programmable
1633completion code had generated them directly from a completion specification
1634with the same flags.
1635If @var{word} is specified, only those completions matching @var{word}
1636will be displayed.
1637
1638The return value is true unless an invalid option is supplied, or no
1639matches were generated.
1640
1641@item complete
1642@btindex complete
1643@example
1644@code{complete [-abcdefgjksuv] [-o @var{comp-option}] [-A @var{action}] [-G @var{globpat}] [-W @var{wordlist}]
1645[-P @var{prefix}] [-S @var{suffix}] [-X @var{filterpat}] [-F @var{function}]
1646[-C @var{command}] @var{name} [@var{name} @dots{}]}
1647@code{complete -pr [@var{name} @dots{}]}
1648@end example
1649
1650Specify how arguments to each @var{name} should be completed.
1651If the @option{-p} option is supplied, or if no options are supplied, existing
1652completion specifications are printed in a way that allows them to be
1653reused as input.
1654The @option{-r} option removes a completion specification for
1655each @var{name}, or, if no @var{name}s are supplied, all
1656completion specifications.
1657
1658The process of applying these completion specifications when word completion
1659is attempted is described above (@pxref{Programmable Completion}).
1660
1661Other options, if specified, have the following meanings.
1662The arguments to the @option{-G}, @option{-W}, and @option{-X} options
1663(and, if necessary, the @option{-P} and @option{-S} options)
1664should be quoted to protect them from expansion before the
1665@code{complete} builtin is invoked.
1666
1667
1668@table @code
1669@item -o @var{comp-option}
1670The @var{comp-option} controls several aspects of the compspec's behavior
1671beyond the simple generation of completions.
1672@var{comp-option} may be one of:
1673
1674@table @code
1675
1676@item bashdefault
1677Perform the rest of the default Bash completions if the compspec
1678generates no matches.
1679
1680@item default
1681Use Readline's default filename completion if the compspec generates
1682no matches.
1683
1684@item dirnames
1685Perform directory name completion if the compspec generates no matches.
1686
1687@item filenames
1688Tell Readline that the compspec generates filenames, so it can perform any
1689filename-specific processing (like adding a slash to directory names or
1690suppressing trailing spaces). This option is intended to be used with
1691shell functions specified with @option{-F}.
1692
1693@item nospace
1694Tell Readline not to append a space (the default) to words completed at
1695the end of the line.
1696@end table
1697
1698@item -A @var{action}
1699The @var{action} may be one of the following to generate a list of possible
1700completions:
1701
1702@table @code
1703@item alias
1704Alias names. May also be specified as @option{-a}.
1705
1706@item arrayvar
1707Array variable names.
1708
1709@item binding
1710Readline key binding names (@pxref{Bindable Readline Commands}).
1711
1712@item builtin
1713Names of shell builtin commands. May also be specified as @option{-b}.
1714
1715@item command
1716Command names. May also be specified as @option{-c}.
1717
1718@item directory
1719Directory names. May also be specified as @option{-d}.
1720
1721@item disabled
1722Names of disabled shell builtins.
1723
1724@item enabled
1725Names of enabled shell builtins.
1726
1727@item export
1728Names of exported shell variables. May also be specified as @option{-e}.
1729
1730@item file
1731File names. May also be specified as @option{-f}.
1732
1733@item function
1734Names of shell functions.
1735
1736@item group
1737Group names. May also be specified as @option{-g}.
1738
1739@item helptopic
1740Help topics as accepted by the @code{help} builtin (@pxref{Bash Builtins}).
1741
1742@item hostname
1743Hostnames, as taken from the file specified by the
1744@env{HOSTFILE} shell variable (@pxref{Bash Variables}).
1745
1746@item job
1747Job names, if job control is active. May also be specified as @option{-j}.
1748
1749@item keyword
1750Shell reserved words. May also be specified as @option{-k}.
1751
1752@item running
1753Names of running jobs, if job control is active.
1754
1755@item service
1756Service names. May also be specified as @option{-s}.
1757
1758@item setopt
1759Valid arguments for the @option{-o} option to the @code{set} builtin
1760(@pxref{The Set Builtin}).
1761
1762@item shopt
1763Shell option names as accepted by the @code{shopt} builtin
1764(@pxref{Bash Builtins}).
1765
1766@item signal
1767Signal names.
1768
1769@item stopped
1770Names of stopped jobs, if job control is active.
1771
1772@item user
1773User names. May also be specified as @option{-u}.
1774
1775@item variable
1776Names of all shell variables. May also be specified as @option{-v}.
1777@end table
1778
1779@item -G @var{globpat}
1780The filename expansion pattern @var{globpat} is expanded to generate
1781the possible completions.
1782
1783@item -W @var{wordlist}
1784The @var{wordlist} is split using the characters in the
1785@env{IFS} special variable as delimiters, and each resultant word
1786is expanded.
1787The possible completions are the members of the resultant list which
1788match the word being completed.
1789
1790@item -C @var{command}
1791@var{command} is executed in a subshell environment, and its output is
1792used as the possible completions.
1793
1794@item -F @var{function}
1795The shell function @var{function} is executed in the current shell
1796environment.
1797When it finishes, the possible completions are retrieved from the value
1798of the @env{COMPREPLY} array variable.
1799
1800@item -X @var{filterpat}
1801@var{filterpat} is a pattern as used for filename expansion.
1802It is applied to the list of possible completions generated by the
1803preceding options and arguments, and each completion matching
1804@var{filterpat} is removed from the list.
1805A leading @samp{!} in @var{filterpat} negates the pattern; in this
1806case, any completion not matching @var{filterpat} is removed.
1807
1808@item -P @var{prefix}
1809@var{prefix} is added at the beginning of each possible completion
1810after all other options have been applied.
1811
1812@item -S @var{suffix}
1813@var{suffix} is appended to each possible completion
1814after all other options have been applied.
1815@end table
1816
1817The return value is true unless an invalid option is supplied, an option
1818other than @option{-p} or @option{-r} is supplied without a @var{name}
1819argument, an attempt is made to remove a completion specification for
1820a @var{name} for which no specification exists, or
1821an error occurs adding a completion specification.
1822
1823@end table
1824@end ifset