1 @comment %**start of header (This is for running Texinfo on a region.)
2 @setfilename rluser.info
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7 This file documents the end user interface to the GNU command line
8 editing features. It is to be an appendix to manuals for programs which
9 use these features. There is a document entitled "readline.texinfo"
10 which contains both end-user and programmer documentation for the
13 Copyright (C) 1988-2000 Free Software Foundation, Inc.
15 Authored by Brian Fox and Chet Ramey.
17 Permission is granted to process this file through Tex and print the
18 results, provided the printed document carries copying permission notice
19 identical to this one except for the removal of this paragraph (this
20 paragraph not being relevant to the printed manual).
22 Permission is granted to make and distribute verbatim copies of this manual
23 provided the copyright notice and this permission notice are preserved on
26 Permission is granted to copy and distribute modified versions of this
27 manual under the conditions for verbatim copying, provided also that the
28 GNU Copyright statement is available to the distributee, and provided that
29 the entire resulting derived work is distributed under the terms of a
30 permission notice identical to this one.
32 Permission is granted to copy and distribute translations of this manual
33 into another language, under the above conditions for modified versions.
36 @comment If you are including this manual as an appendix, then set the
37 @comment variable readline-appendix.
43 @node Command Line Editing
44 @chapter Command Line Editing
46 This chapter describes the basic features of the @sc{gnu}
47 command line editing interface.
49 Command line editing is provided by the Readline library, which is
50 used by several different programs, including Bash.
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
59 * Readline vi Mode:: A short description of how to make Readline
60 behave like the vi editor.
62 * Programmable Completion:: How to specify the possible completions for
64 * Programmable Completion Builtins:: Builtin commands to specify how to
65 complete arguments for a particular command.
69 @node Introduction and Notation
70 @section Introduction to Line Editing
72 The following paragraphs describe the notation used to represent
75 The text @kbd{C-k} is read as `Control-K' and describes the character
76 produced when the @key{k} key is pressed while the Control key
79 The text @kbd{M-k} is read as `Meta-K' and describes the character
80 produced when the Meta key (if you have one) is depressed, and the @key{k}
82 The Meta key is labeled @key{ALT} on many keyboards.
83 On keyboards with two keys labeled @key{ALT} (usually to either side of
84 the space bar), the @key{ALT} on the left side is generally set to
86 The @key{ALT} key on the right may also be configured to work as a
87 Meta key or may be configured as some other modifier, such as a
88 Compose key for typing accented characters.
90 If you do not have a Meta or @key{ALT} key, or another key working as
91 a Meta key, the identical keystroke can be generated by typing @key{ESC}
92 @emph{first}, and then typing @key{k}.
93 Either process is known as @dfn{metafying} the @key{k} key.
95 The text @kbd{M-C-k} is read as `Meta-Control-k' and describes the
96 character produced by @dfn{metafying} @kbd{C-k}.
98 In addition, several keys have their own names. Specifically,
99 @key{DEL}, @key{ESC}, @key{LFD}, @key{SPC}, @key{RET}, and @key{TAB} all
100 stand for themselves when seen in this text, or in an init file
101 (@pxref{Readline Init File}).
102 If your keyboard lacks a @key{LFD} key, typing @key{C-j} will
103 produce the desired character.
104 The @key{RET} key may be labeled @key{Return} or @key{Enter} on
107 @node Readline Interaction
108 @section Readline Interaction
109 @cindex interaction, readline
111 Often during an interactive session you type in a long line of text,
112 only to notice that the first word on the line is misspelled. The
113 Readline library gives you a set of commands for manipulating the text
114 as you type it in, allowing you to just fix your typo, and not forcing
115 you to retype the majority of the line. Using these editing commands,
116 you move the cursor to the place that needs correction, and delete or
117 insert the text of the corrections. Then, when you are satisfied with
118 the line, you simply press @key{RET}. You do not have to be at the
119 end of the line to press @key{RET}; the entire line is accepted
120 regardless of the location of the cursor within the line.
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.
130 @node Readline Bare Essentials
131 @subsection Readline Bare Essentials
132 @cindex notation, readline
133 @cindex command editing
134 @cindex editing command lines
136 In order to enter characters into the line, simply type them. The typed
137 character appears where the cursor was, and then the cursor moves one
138 space to the right. If you mistype a character, you can use your
139 erase character to back up and delete the mistyped character.
141 Sometimes you may mistype a character, and
142 not notice the error until you have typed several other characters. In
143 that case, you can type @kbd{C-b} to move the cursor to the left, and then
144 correct your mistake. Afterwards, you can move the cursor to the right
147 When you add text in the middle of a line, you will notice that characters
148 to the right of the cursor are `pushed over' to make room for the text
149 that you have inserted. Likewise, when you delete text behind the cursor,
150 characters to the right of the cursor are `pulled back' to fill in the
151 blank space created by the removal of the text. A list of the bare
152 essentials for editing the text of an input line follows.
156 Move back one character.
158 Move forward one character.
159 @item @key{DEL} or @key{Backspace}
160 Delete the character to the left of the cursor.
162 Delete the character underneath the cursor.
163 @item @w{Printing characters}
164 Insert the character into the line at the cursor.
165 @item @kbd{C-_} or @kbd{C-x C-u}
166 Undo the last editing command. You can undo all the way back to an
171 (Depending on your configuration, the @key{Backspace} key be set to
172 delete the character to the left of the cursor and the @key{DEL} key set
173 to delete the character underneath the cursor, like @kbd{C-d}, rather
174 than the character to the left of the cursor.)
176 @node Readline Movement Commands
177 @subsection Readline Movement Commands
180 The above table describes the most basic keystrokes that you need
181 in order to do editing of the input line. For your convenience, many
182 other 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
188 Move to the start of the line.
190 Move to the end of the line.
192 Move forward a word, where a word is composed of letters and digits.
194 Move backward a word.
196 Clear the screen, reprinting the current line at the top.
199 Notice how @kbd{C-f} moves forward a character, while @kbd{M-f} moves
200 forward a word. It is a loose convention that control keystrokes
201 operate on characters while meta keystrokes operate on words.
203 @node Readline Killing Commands
204 @subsection Readline Killing Commands
209 @dfn{Killing} text means to delete the text from the line, but to save
210 it away for later use, usually by @dfn{yanking} (re-inserting)
211 it back into the line.
212 (`Cut' and `paste' are more recent jargon for `kill' and `yank'.)
214 If the description for a command says that it `kills' text, then you can
215 be sure that you can get the text back in a different (or the same)
218 When you use a kill command, the text is saved in a @dfn{kill-ring}.
219 Any number of consecutive kills save all of the killed text together, so
220 that when you yank it back, you get it all. The kill
221 ring is not line specific; the text that you killed on a previously
222 typed line is available to be yanked back later, when you are typing
226 Here is the list of commands for killing text.
230 Kill the text from the current cursor position to the end of the line.
233 Kill from the cursor to the end of the current word, or, if between
234 words, to the end of the next word.
235 Word boundaries are the same as those used by @kbd{M-f}.
238 Kill from the cursor the start of the previous word, or, if between
239 words, to the start of the previous word.
240 Word boundaries are the same as those used by @kbd{M-b}.
243 Kill from the cursor to the previous whitespace. This is different than
244 @kbd{M-@key{DEL}} because the word boundaries differ.
248 Here is how to @dfn{yank} the text back into the line. Yanking
249 means to copy the most-recently-killed text from the kill buffer.
253 Yank the most recently killed text back into the buffer at the cursor.
256 Rotate the kill-ring, and yank the new top. You can only do this if
257 the prior command is @kbd{C-y} or @kbd{M-y}.
260 @node Readline Arguments
261 @subsection Readline Arguments
263 You can pass numeric arguments to Readline commands. Sometimes the
264 argument acts as a repeat count, other times it is the @i{sign} of the
265 argument that is significant. If you pass a negative argument to a
266 command which normally acts in a forward direction, that command will
267 act in a backward direction. For example, to kill text back to the
268 start of the line, you might type @samp{M-- C-k}.
270 The general way to pass numeric arguments to a command is to type meta
271 digits before the command. If the first `digit' typed is a minus
272 sign (@samp{-}), then the sign of the argument will be negative. Once
273 you have typed one meta digit to get the argument started, you can type
274 the remainder of the digits, and then the command. For example, to give
275 the @kbd{C-d} command an argument of 10, you could type @samp{M-1 0 C-d},
276 which will delete the next ten characters on the input line.
279 @subsection Searching for Commands in the History
281 Readline provides commands for searching through the command history
283 (@pxref{Bash History Facilities})
285 for lines containing a specified string.
286 There are two search modes: @dfn{incremental} and @dfn{non-incremental}.
288 Incremental searches begin before the user has finished typing the
290 As each character of the search string is typed, Readline displays
291 the next entry from the history matching the string typed so far.
292 An incremental search requires only as many characters as needed to
293 find the desired history entry.
294 To search backward in the history for a particular string, type
295 @kbd{C-r}. Typing @kbd{C-s} searches forward through the history.
296 The characters present in the value of the @code{isearch-terminators} variable
297 are used to terminate an incremental search.
298 If 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.
301 When the search is terminated, the history entry containing the
302 search string becomes the current line.
304 To find other matching entries in the history list, type @kbd{C-r} or
305 @kbd{C-s} as appropriate.
306 This will search backward or forward in the history for the next
307 entry matching the search string typed so far.
308 Any other key sequence bound to a Readline command will terminate
309 the search and execute that command.
310 For instance, a @key{RET} will terminate the search and accept
311 the line, thereby executing the command from the history list.
312 A movement command will terminate the search, make the last line found
313 the current line, and begin editing.
315 Non-incremental searches read the entire search string before starting
316 to search for matching history lines. The search string may be
317 typed by the user or be part of the contents of the current line.
319 @node Readline Init File
320 @section Readline Init File
321 @cindex initialization file, readline
323 Although the Readline library comes with a set of Emacs-like
324 keybindings installed by default, it is possible to use a different set
326 Any user can customize programs that use Readline by putting
327 commands in an @dfn{inputrc} file, conventionally in his home directory.
330 file is taken from the value of the shell variable @env{INPUTRC}. If
332 @ifclear BashFeatures
333 file is taken from the value of the environment variable @env{INPUTRC}. If
335 that variable is unset, the default is @file{~/.inputrc}.
337 When a program which uses the Readline library starts up, the
338 init file is read, and the key bindings are set.
340 In addition, the @code{C-x C-r} command re-reads this init file, thus
341 incorporating any changes that you might have made to it.
344 * Readline Init File Syntax:: Syntax for the commands in the inputrc file.
346 * Conditional Init Constructs:: Conditional key bindings in the inputrc file.
348 * Sample Init File:: An example inputrc file.
351 @node Readline Init File Syntax
352 @subsection Readline Init File Syntax
354 There are only a few basic constructs allowed in the
355 Readline init file. Blank lines are ignored.
356 Lines beginning with a @samp{#} are comments.
357 Lines beginning with a @samp{$} indicate conditional
358 constructs (@pxref{Conditional Init Constructs}). Other lines
359 denote variable settings and key bindings.
362 @item Variable Settings
363 You can modify the run-time behavior of Readline by
364 altering the values of variables in Readline
365 using the @code{set} command within the init file.
366 The syntax is simple:
369 set @var{variable} @var{value}
373 Here, for example, is how to
374 change from the default Emacs-like key binding to use
375 @code{vi} line editing commands:
381 Variable names and values, where appropriate, are recognized without regard
385 The @w{@code{bind -V}} command lists the current Readline variable names
386 and values. @xref{Bash Builtins}.
389 A great deal of run-time behavior is changeable with the following
392 @cindex variables, readline
397 Controls what happens when Readline wants to ring the terminal bell.
398 If set to @samp{none}, Readline never rings the bell. If set to
399 @samp{visible}, Readline uses a visible bell if one is available.
400 If set to @samp{audible} (the default), Readline attempts to ring
404 @vindex comment-begin
405 The string to insert at the beginning of the line when the
406 @code{insert-comment} command is executed. The default value
409 @item completion-ignore-case
410 If set to @samp{on}, Readline performs filename matching and completion
411 in a case-insensitive fashion.
412 The default value is @samp{off}.
414 @item completion-query-items
415 @vindex completion-query-items
416 The number of possible completions that determines when the user is
417 asked whether he wants to see the list of possibilities. If the
418 number of possible completions is greater than this value,
419 Readline will ask the user whether or not he wishes to view
420 them; otherwise, they are simply listed.
421 This variable must be set to an integer value greater than or equal to 0.
422 The default limit is @code{100}.
426 If set to @samp{on}, Readline will convert characters with the
427 eighth bit set to an @sc{ascii} key sequence by stripping the eighth
428 bit and prefixing an @key{ESC} character, converting them to a
429 meta-prefixed key sequence. The default value is @samp{on}.
431 @item disable-completion
432 @vindex disable-completion
433 If set to @samp{On}, Readline will inhibit word completion.
434 Completion characters will be inserted into the line as if they had
435 been mapped to @code{self-insert}. The default is @samp{off}.
439 The @code{editing-mode} variable controls which default set of
440 key bindings is used. By default, Readline starts up in Emacs editing
441 mode, where the keystrokes are most similar to Emacs. This variable can be
442 set to either @samp{emacs} or @samp{vi}.
445 @vindex enable-keypad
446 When set to @samp{on}, Readline will try to enable the application
447 keypad when it is called. Some systems need this to enable the
448 arrow keys. The default is @samp{off}.
452 If set to @samp{on}, tilde expansion is performed when Readline
453 attempts word completion. The default is @samp{off}.
455 @item horizontal-scroll-mode
456 @vindex horizontal-scroll-mode
457 This variable can be set to either @samp{on} or @samp{off}. Setting it
458 to @samp{on} means that the text of the lines being edited will scroll
459 horizontally on a single screen line when they are longer than the width
460 of the screen, instead of wrapping onto a new screen line. By default,
461 this variable is set to @samp{off}.
466 If set to @samp{on}, Readline will enable eight-bit input (it
467 will not clear the eighth bit in the characters it reads),
468 regardless of what the terminal claims it can support. The
469 default value is @samp{off}. The name @code{meta-flag} is a
470 synonym for this variable.
472 @item isearch-terminators
473 @vindex isearch-terminators
474 The string of characters that should terminate an incremental search without
475 subsequently executing the character as a command (@pxref{Searching}).
476 If this variable has not been given a value, the characters @key{ESC} and
477 @kbd{C-J} will terminate an incremental search.
481 Sets Readline's idea of the current keymap for key binding commands.
482 Acceptable @code{keymap} names are
484 @code{emacs-standard},
489 @code{vi-command}, and
491 @code{vi} is equivalent to @code{vi-command}; @code{emacs} is
492 equivalent to @code{emacs-standard}. The default value is @code{emacs}.
493 The value of the @code{editing-mode} variable also affects the
496 @item mark-directories
497 If set to @samp{on}, completed directory names have a slash
498 appended. The default is @samp{on}.
500 @item mark-modified-lines
501 @vindex mark-modified-lines
502 This variable, when set to @samp{on}, causes Readline to display an
503 asterisk (@samp{*}) at the start of history lines which have been modified.
504 This variable is @samp{off} by default.
508 If set to @samp{on}, Readline will display characters with the
509 eighth bit set directly rather than as a meta-prefixed escape
510 sequence. The default is @samp{off}.
512 @item print-completions-horizontally
513 If set to @samp{on}, Readline will display completions with matches
514 sorted horizontally in alphabetical order, rather than down the screen.
515 The default is @samp{off}.
517 @item show-all-if-ambiguous
518 @vindex show-all-if-ambiguous
519 This alters the default behavior of the completion functions. If
521 words which have more than one possible completion cause the
522 matches to be listed immediately instead of ringing the bell.
523 The default value is @samp{off}.
526 @vindex visible-stats
527 If set to @samp{on}, a character denoting a file's type
528 is appended to the filename when listing possible
529 completions. The default is @samp{off}.
534 The syntax for controlling key bindings in the init file is
535 simple. First you need to find the name of the command that you
536 want to change. The following sections contain tables of the command
537 name, the default keybinding, if any, and a short description of what
540 Once you know the name of the command, simply place on a line
541 in the init file the name of the key
542 you wish to bind the command to, a colon, and then the name of the
543 command. The name of the key
544 can be expressed in different ways, depending on what you find most
547 In addition to command names, readline allows keys to be bound
548 to a string that is inserted when the key is pressed (a @var{macro}).
551 The @w{@code{bind -p}} command displays Readline function names and
552 bindings in a format that can put directly into an initialization file.
553 @xref{Bash Builtins}.
557 @item @w{@var{keyname}: @var{function-name} or @var{macro}}
558 @var{keyname} is the name of a key spelled out in English. For example:
560 Control-u: universal-argument
561 Meta-Rubout: backward-kill-word
562 Control-o: "> output"
565 In the above example, @kbd{C-u} is bound to the function
566 @code{universal-argument},
567 @kbd{M-DEL} is bound to the function @code{backward-kill-word}, and
568 @kbd{C-o} is bound to run the macro
569 expressed on the right hand side (that is, to insert the text
570 @samp{> output} into the line).
572 A number of symbolic character names are recognized while
573 processing this key binding syntax:
587 @item @w{"@var{keyseq}": @var{function-name} or @var{macro}}
588 @var{keyseq} differs from @var{keyname} above in that strings
589 denoting an entire key sequence can be specified, by placing
590 the key sequence in double quotes. Some @sc{gnu} Emacs style key
591 escapes can be used, as in the following example, but the
592 special character names are not recognized.
595 "\C-u": universal-argument
596 "\C-x\C-r": re-read-init-file
597 "\e[11~": "Function Key 1"
600 In the above example, @kbd{C-u} is again bound to the function
601 @code{universal-argument} (just as it was in the first example),
602 @samp{@kbd{C-x} @kbd{C-r}} is bound to the function @code{re-read-init-file},
603 and @samp{@key{ESC} @key{[} @key{1} @key{1} @key{~}} is bound to insert
604 the text @samp{Function Key 1}.
608 The following @sc{gnu} Emacs style escape sequences are available when
609 specifying key sequences:
621 @key{"}, a double quotation mark
623 @key{'}, a single quote or apostrophe
626 In addition to the @sc{gnu} Emacs style escape sequences, a second
627 set of backslash escapes is available:
647 the character whose @sc{ascii} code is the octal value @var{nnn}
648 (one to three digits)
650 the character whose @sc{ascii} code is the hexadecimal value @var{nnn}
651 (one to three digits)
654 When entering the text of a macro, single or double quotes must
655 be used to indicate a macro definition.
656 Unquoted text is assumed to be a function name.
657 In the macro body, the backslash escapes described above are expanded.
658 Backslash will quote any other character in the macro text,
659 including @samp{"} and @samp{'}.
660 For example, the following binding will make @samp{@kbd{C-x} \}
661 insert a single @samp{\} into the line:
668 @node Conditional Init Constructs
669 @subsection Conditional Init Constructs
671 Readline implements a facility similar in spirit to the conditional
672 compilation features of the C preprocessor which allows key
673 bindings and variable settings to be performed as the result
674 of tests. There are four parser directives used.
678 The @code{$if} construct allows bindings to be made based on the
679 editing mode, the terminal being used, or the application using
680 Readline. The text of the test extends to the end of the line;
681 no characters are required to isolate it.
685 The @code{mode=} form of the @code{$if} directive is used to test
686 whether Readline is in @code{emacs} or @code{vi} mode.
687 This may be used in conjunction
688 with the @samp{set keymap} command, for instance, to set bindings in
689 the @code{emacs-standard} and @code{emacs-ctlx} keymaps only if
690 Readline is starting out in @code{emacs} mode.
693 The @code{term=} form may be used to include terminal-specific
694 key bindings, perhaps to bind the key sequences output by the
695 terminal's function keys. The word on the right side of the
696 @samp{=} is tested against both the full name of the terminal and
697 the portion of the terminal name before the first @samp{-}. This
698 allows @code{sun} to match both @code{sun} and @code{sun-cmd},
702 The @var{application} construct is used to include
703 application-specific settings. Each program using the Readline
704 library sets the @var{application name}, and you can test for
706 This could be used to bind key sequences to functions useful for
707 a specific program. For instance, the following command adds a
708 key sequence that quotes the current or previous word in Bash:
711 # Quote the current or previous word
712 "\C-xq": "\eb\"\ef\""
718 This command, as seen in the previous example, terminates an
722 Commands in this branch of the @code{$if} directive are executed if
726 This directive takes a single filename as an argument and reads commands
727 and bindings from that file.
728 For example, the following directive reads from @file{/etc/inputrc}:
730 $include /etc/inputrc
734 @node Sample Init File
735 @subsection Sample Init File
737 Here is an example of an @var{inputrc} file. This illustrates key
738 binding, variable assignment, and conditional syntax.
742 # This file controls the behaviour of line input editing for
743 # programs that use the Gnu Readline library. Existing programs
744 # include FTP, Bash, and Gdb.
746 # You can re-read the inputrc file with C-x C-r.
747 # Lines beginning with '#' are comments.
749 # First, include any systemwide bindings and variable assignments from
751 $include /etc/Inputrc
754 # Set various bindings for emacs mode.
756 set editing-mode emacs
760 Meta-Control-h: backward-kill-word Text after the function name is ignored
763 # Arrow keys in keypad mode
765 #"\M-OD": backward-char
766 #"\M-OC": forward-char
767 #"\M-OA": previous-history
768 #"\M-OB": next-history
770 # Arrow keys in ANSI mode
772 "\M-[D": backward-char
773 "\M-[C": forward-char
774 "\M-[A": previous-history
775 "\M-[B": next-history
777 # Arrow keys in 8 bit keypad mode
779 #"\M-\C-OD": backward-char
780 #"\M-\C-OC": forward-char
781 #"\M-\C-OA": previous-history
782 #"\M-\C-OB": next-history
784 # Arrow keys in 8 bit ANSI mode
786 #"\M-\C-[D": backward-char
787 #"\M-\C-[C": forward-char
788 #"\M-\C-[A": previous-history
789 #"\M-\C-[B": next-history
795 # An old-style binding. This happens to be the default.
798 # Macros that are convenient for shell interaction
801 "\C-xp": "PATH=$@{PATH@}\e\C-e\C-a\ef\C-f"
802 # prepare to type a quoted word -- insert open and close double quotes
803 # and move to just after the open quote
805 # insert a backslash (testing backslash escapes in sequences and macros)
807 # Quote the current or previous word
808 "\C-xq": "\eb\"\ef\""
809 # Add a binding to refresh the line, which is unbound
810 "\C-xr": redraw-current-line
811 # Edit variable on current line.
812 "\M-\C-v": "\C-a\C-k$\C-y\M-\C-e\C-a\C-y="
815 # use a visible bell if one is available
816 set bell-style visible
818 # don't strip characters to 7 bits when reading
821 # allow iso-latin1 characters to be inserted rather than converted to
822 # prefix-meta sequences
825 # display characters with the eighth bit set directly rather than
826 # as meta-prefixed characters
829 # if there are more than 150 possible completions for a word, ask the
830 # user if he wants to see all of them
831 set completion-query-items 150
837 "\M-.": yank-last-arg
841 @node Bindable Readline Commands
842 @section Bindable Readline Commands
845 * Commands For Moving:: Moving about the line.
846 * Commands For History:: Getting at previous lines.
847 * Commands For Text:: Commands for changing text.
848 * Commands For Killing:: Commands for killing and yanking.
849 * Numeric Arguments:: Specifying numeric arguments, repeat counts.
850 * Commands For Completion:: Getting Readline to do the typing for you.
851 * Keyboard Macros:: Saving and re-executing typed characters
852 * Miscellaneous Commands:: Other miscellaneous commands.
855 This section describes Readline commands that may be bound to key
858 You can list your key bindings by executing
859 @w{@code{bind -P}} or, for a more terse format, suitable for an
860 @var{inputrc} file, @w{@code{bind -p}}. (@xref{Bash Builtins}.)
862 Command names without an accompanying key sequence are unbound by default.
864 In the following descriptions, @dfn{point} refers to the current cursor
865 position, and @dfn{mark} refers to a cursor position saved by the
866 @code{set-mark} command.
867 The text between the point and mark is referred to as the @dfn{region}.
869 @node Commands For Moving
870 @subsection Commands For Moving
872 @item beginning-of-line (C-a)
873 Move to the start of the current line.
875 @item end-of-line (C-e)
876 Move to the end of the line.
878 @item forward-char (C-f)
879 Move forward a character.
881 @item backward-char (C-b)
882 Move back a character.
884 @item forward-word (M-f)
885 Move forward to the end of the next word. Words are composed of
888 @item backward-word (M-b)
889 Move back to the start of the current or previous word. Words are
890 composed of letters and digits.
892 @item clear-screen (C-l)
893 Clear the screen and redraw the current line,
894 leaving the current line at the top of the screen.
896 @item redraw-current-line ()
897 Refresh the current line. By default, this is unbound.
901 @node Commands For History
902 @subsection Commands For Manipulating The History
905 @item accept-line (Newline or Return)
907 Accept the line regardless of where the cursor is.
909 non-empty, add it to the history list according to the setting of
910 the @env{HISTCONTROL} and @env{HISTIGNORE} variables.
911 If this line is a modified history line, then restore the history line
912 to its original state.
914 @ifclear BashFeatures
915 Accept the line regardless of where the cursor is.
917 non-empty, it may be added to the history list for future recall with
918 @code{add_history()}.
919 If this line is a modified history line, the history line is restored
920 to its original state.
923 @item previous-history (C-p)
924 Move `back' through the history list, fetching the previous command.
926 @item next-history (C-n)
927 Move `forward' through the history list, fetching the next command.
929 @item beginning-of-history (M-<)
930 Move to the first line in the history.
932 @item end-of-history (M->)
933 Move to the end of the input history, i.e., the line currently
936 @item reverse-search-history (C-r)
937 Search backward starting at the current line and moving `up' through
938 the history as necessary. This is an incremental search.
940 @item forward-search-history (C-s)
941 Search forward starting at the current line and moving `down' through
942 the the history as necessary. This is an incremental search.
944 @item non-incremental-reverse-search-history (M-p)
945 Search backward starting at the current line and moving `up'
946 through the history as necessary using a non-incremental search
947 for a string supplied by the user.
949 @item non-incremental-forward-search-history (M-n)
950 Search forward starting at the current line and moving `down'
951 through the the history as necessary using a non-incremental search
952 for a string supplied by the user.
954 @item history-search-forward ()
955 Search forward through the history for the string of characters
956 between the start of the current line and the point.
957 This is a non-incremental search.
958 By default, this command is unbound.
960 @item history-search-backward ()
961 Search backward through the history for the string of characters
962 between the start of the current line and the point. This
963 is a non-incremental search. By default, this command is unbound.
965 @item yank-nth-arg (M-C-y)
966 Insert the first argument to the previous command (usually
967 the second word on the previous line) at point.
968 With an argument @var{n},
969 insert the @var{n}th word from the previous command (the words
970 in the previous command begin with word 0). A negative argument
971 inserts the @var{n}th word from the end of the previous command.
973 @item yank-last-arg (M-. or M-_)
974 Insert last argument to the previous command (the last word of the
975 previous history entry). With an
976 argument, behave exactly like @code{yank-nth-arg}.
977 Successive calls to @code{yank-last-arg} move back through the history
978 list, inserting the last argument of each line in turn.
982 @node Commands For Text
983 @subsection Commands For Changing Text
986 @item delete-char (C-d)
987 Delete the character at point. If point is at the
988 beginning of the line, there are no characters in the line, and
989 the last character typed was not bound to @code{delete-char}, then
992 @item backward-delete-char (Rubout)
993 Delete the character behind the cursor. A numeric argument means
994 to kill the characters instead of deleting them.
996 @item forward-backward-delete-char ()
997 Delete the character under the cursor, unless the cursor is at the
998 end of the line, in which case the character behind the cursor is
999 deleted. By default, this is not bound to a key.
1001 @item quoted-insert (C-q or C-v)
1002 Add the next character typed to the line verbatim. This is
1003 how to insert key sequences like @kbd{C-q}, for example.
1005 @ifclear BashFeatures
1006 @item tab-insert (M-@key{TAB})
1007 Insert a tab character.
1010 @item self-insert (a, b, A, 1, !, @dots{})
1013 @item transpose-chars (C-t)
1014 Drag the character before the cursor forward over
1015 the character at the cursor, moving the
1016 cursor forward as well. If the insertion point
1017 is at the end of the line, then this
1018 transposes the last two characters of the line.
1019 Negative arguments have no effect.
1021 @item transpose-words (M-t)
1022 Drag the word before point past the word after point,
1023 moving point past that word as well.
1025 @item upcase-word (M-u)
1026 Uppercase the current (or following) word. With a negative argument,
1027 uppercase the previous word, but do not move the cursor.
1029 @item downcase-word (M-l)
1030 Lowercase the current (or following) word. With a negative argument,
1031 lowercase the previous word, but do not move the cursor.
1033 @item capitalize-word (M-c)
1034 Capitalize the current (or following) word. With a negative argument,
1035 capitalize the previous word, but do not move the cursor.
1039 @node Commands For Killing
1040 @subsection Killing And Yanking
1044 @item kill-line (C-k)
1045 Kill the text from point to the end of the line.
1047 @item backward-kill-line (C-x Rubout)
1048 Kill backward to the beginning of the line.
1050 @item unix-line-discard (C-u)
1051 Kill backward from the cursor to the beginning of the current line.
1053 @item kill-whole-line ()
1054 Kill all characters on the current line, no matter where point is.
1055 By default, this is unbound.
1057 @item kill-word (M-d)
1058 Kill from point to the end of the current word, or if between
1059 words, to the end of the next word.
1060 Word boundaries are the same as @code{forward-word}.
1062 @item backward-kill-word (M-@key{DEL})
1063 Kill the word behind point.
1064 Word boundaries are the same as @code{backward-word}.
1066 @item unix-word-rubout (C-w)
1067 Kill the word behind point, using white space as a word boundary.
1068 The killed text is saved on the kill-ring.
1070 @item delete-horizontal-space ()
1071 Delete all spaces and tabs around point. By default, this is unbound.
1073 @item kill-region ()
1074 Kill the text in the current region.
1075 By default, this command is unbound.
1077 @item copy-region-as-kill ()
1078 Copy the text in the region to the kill buffer, so it can be yanked
1079 right away. By default, this command is unbound.
1081 @item copy-backward-word ()
1082 Copy the word before point to the kill buffer.
1083 The word boundaries are the same as @code{backward-word}.
1084 By default, this command is unbound.
1086 @item copy-forward-word ()
1087 Copy the word following point to the kill buffer.
1088 The word boundaries are the same as @code{forward-word}.
1089 By default, this command is unbound.
1092 Yank the top of the kill ring into the buffer at point.
1094 @item yank-pop (M-y)
1095 Rotate the kill-ring, and yank the new top. You can only do this if
1096 the prior command is @code{yank} or @code{yank-pop}.
1099 @node Numeric Arguments
1100 @subsection Specifying Numeric Arguments
1103 @item digit-argument (@kbd{M-0}, @kbd{M-1}, @dots{} @kbd{M--})
1104 Add this digit to the argument already accumulating, or start a new
1105 argument. @kbd{M--} starts a negative argument.
1107 @item universal-argument ()
1108 This is another way to specify an argument.
1109 If this command is followed by one or more digits, optionally with a
1110 leading minus sign, those digits define the argument.
1111 If the command is followed by digits, executing @code{universal-argument}
1112 again ends the numeric argument, but is otherwise ignored.
1113 As a special case, if this command is immediately followed by a
1114 character that is neither a digit or minus sign, the argument count
1115 for the next command is multiplied by four.
1116 The argument count is initially one, so executing this function the
1117 first time makes the argument count four, a second time makes the
1118 argument count sixteen, and so on.
1119 By default, this is not bound to a key.
1122 @node Commands For Completion
1123 @subsection Letting Readline Type For You
1126 @item complete (@key{TAB})
1127 Attempt to perform completion on the text before point.
1128 The actual completion performed is application-specific.
1130 Bash attempts completion treating the text as a variable (if the
1131 text begins with @samp{$}), username (if the text begins with
1132 @samp{~}), hostname (if the text begins with @samp{@@}), or
1133 command (including aliases and functions) in turn. If none
1134 of these produces a match, filename completion is attempted.
1136 @ifclear BashFeatures
1137 The default is filename completion.
1140 @item possible-completions (M-?)
1141 List the possible completions of the text before point.
1143 @item insert-completions (M-*)
1144 Insert all completions of the text before point that would have
1145 been generated by @code{possible-completions}.
1147 @item menu-complete ()
1148 Similar to @code{complete}, but replaces the word to be completed
1149 with a single match from the list of possible completions.
1150 Repeated execution of @code{menu-complete} steps through the list
1151 of possible completions, inserting each match in turn.
1152 At the end of the list of completions, the bell is rung
1153 (subject to the setting of @code{bell-style})
1154 and the original text is restored.
1155 An argument of @var{n} moves @var{n} positions forward in the list
1156 of matches; a negative argument may be used to move backward
1158 This command is intended to be bound to @key{TAB}, but is unbound
1161 @item delete-char-or-list ()
1162 Deletes the character under the cursor if not at the beginning or
1163 end of the line (like @code{delete-char}).
1164 If at the end of the line, behaves identically to
1165 @code{possible-completions}.
1166 This command is unbound by default.
1169 @item complete-filename (M-/)
1170 Attempt filename completion on the text before point.
1172 @item possible-filename-completions (C-x /)
1173 List the possible completions of the text before point,
1174 treating it as a filename.
1176 @item complete-username (M-~)
1177 Attempt completion on the text before point, treating
1180 @item possible-username-completions (C-x ~)
1181 List the possible completions of the text before point,
1182 treating it as a username.
1184 @item complete-variable (M-$)
1185 Attempt completion on the text before point, treating
1186 it as a shell variable.
1188 @item possible-variable-completions (C-x $)
1189 List the possible completions of the text before point,
1190 treating it as a shell variable.
1192 @item complete-hostname (M-@@)
1193 Attempt completion on the text before point, treating
1196 @item possible-hostname-completions (C-x @@)
1197 List the possible completions of the text before point,
1198 treating it as a hostname.
1200 @item complete-command (M-!)
1201 Attempt completion on the text before point, treating
1202 it as a command name. Command completion attempts to
1203 match the text against aliases, reserved words, shell
1204 functions, shell builtins, and finally executable filenames,
1207 @item possible-command-completions (C-x !)
1208 List the possible completions of the text before point,
1209 treating it as a command name.
1211 @item dynamic-complete-history (M-@key{TAB})
1212 Attempt completion on the text before point, comparing
1213 the text against lines from the history list for possible
1216 @item complete-into-braces (M-@{)
1217 Perform filename completion and insert the list of possible completions
1218 enclosed within braces so the list is available to the shell
1219 (@pxref{Brace Expansion}).
1224 @node Keyboard Macros
1225 @subsection Keyboard Macros
1228 @item start-kbd-macro (C-x ()
1229 Begin saving the characters typed into the current keyboard macro.
1231 @item end-kbd-macro (C-x ))
1232 Stop saving the characters typed into the current keyboard macro
1233 and save the definition.
1235 @item call-last-kbd-macro (C-x e)
1236 Re-execute the last keyboard macro defined, by making the characters
1237 in the macro appear as if typed at the keyboard.
1241 @node Miscellaneous Commands
1242 @subsection Some Miscellaneous Commands
1245 @item re-read-init-file (C-x C-r)
1246 Read in the contents of the @var{inputrc} file, and incorporate
1247 any bindings or variable assignments found there.
1250 Abort the current editing command and
1251 ring the terminal's bell (subject to the setting of
1254 @item do-uppercase-version (M-a, M-b, M-@var{x}, @dots{})
1255 If the metafied character @var{x} is lowercase, run the command
1256 that is bound to the corresponding uppercase character.
1258 @item prefix-meta (@key{ESC})
1259 Metafy the next character typed. This is for keyboards
1260 without a meta key. Typing @samp{@key{ESC} f} is equivalent to typing
1263 @item undo (C-_ or C-x C-u)
1264 Incremental undo, separately remembered for each line.
1266 @item revert-line (M-r)
1267 Undo all changes made to this line. This is like executing the @code{undo}
1268 command enough times to get back to the beginning.
1271 @item tilde-expand (M-&)
1273 @ifclear BashFeatures
1274 @item tilde-expand (M-~)
1276 Perform tilde expansion on the current word.
1278 @item set-mark (C-@@)
1279 Set the mark to the point. If a
1280 numeric argument is supplied, the mark is set to that position.
1282 @item exchange-point-and-mark (C-x C-x)
1283 Swap the point with the mark. The current cursor position is set to
1284 the saved position, and the old cursor position is saved as the mark.
1286 @item character-search (C-])
1287 A character is read and point is moved to the next occurrence of that
1288 character. A negative count searches for previous occurrences.
1290 @item character-search-backward (M-C-])
1291 A character is read and point is moved to the previous occurrence
1292 of that character. A negative count searches for subsequent
1295 @item insert-comment (M-#)
1296 The value of the @code{comment-begin}
1297 variable is inserted at the beginning of the current line,
1298 and the line is accepted as if a newline had been typed.
1300 The default value of @code{comment-begin} causes this command
1301 to make the current line a shell comment.
1304 @item dump-functions ()
1305 Print all of the functions and their key bindings to the
1306 Readline output stream. If a numeric argument is supplied,
1307 the output is formatted in such a way that it can be made part
1308 of an @var{inputrc} file. This command is unbound by default.
1310 @item dump-variables ()
1311 Print all of the settable variables and their values to the
1312 Readline output stream. If a numeric argument is supplied,
1313 the output is formatted in such a way that it can be made part
1314 of an @var{inputrc} file. This command is unbound by default.
1316 @item dump-macros ()
1317 Print all of the Readline key sequences bound to macros and the
1318 strings they output. If a numeric argument is supplied,
1319 the output is formatted in such a way that it can be made part
1320 of an @var{inputrc} file. This command is unbound by default.
1323 @item glob-expand-word (C-x *)
1324 The word before point is treated as a pattern for pathname expansion,
1325 and the list of matching file names is inserted, replacing the word.
1327 @item glob-list-expansions (C-x g)
1328 The list of expansions that would have been generated by
1329 @code{glob-expand-word} is displayed, and the line is redrawn.
1331 @item display-shell-version (C-x C-v)
1332 Display version information about the current instance of Bash.
1334 @item shell-expand-line (M-C-e)
1335 Expand the line as the shell does.
1336 This performs alias and history expansion as well as all of the shell
1337 word expansions (@pxref{Shell Expansions}).
1339 @item history-expand-line (M-^)
1340 Perform history expansion on the current line.
1342 @item magic-space ()
1343 Perform history expansion on the current line and insert a space
1344 (@pxref{History Interaction}).
1346 @item alias-expand-line ()
1347 Perform alias expansion on the current line (@pxref{Aliases}).
1349 @item history-and-alias-expand-line ()
1350 Perform history and alias expansion on the current line.
1352 @item insert-last-argument (M-. or M-_)
1353 A synonym for @code{yank-last-arg}.
1355 @item operate-and-get-next (C-o)
1356 Accept the current line for execution and fetch the next line
1357 relative to the current line from the history for editing. Any
1358 argument is ignored.
1360 @item emacs-editing-mode (C-e)
1361 When in @code{vi} editing mode, this causes a switch back to
1362 @code{emacs} editing mode, as if the command @samp{set -o emacs} had
1369 @node Readline vi Mode
1370 @section Readline vi Mode
1372 While the Readline library does not have a full set of @code{vi}
1373 editing functions, it does contain enough to allow simple editing
1374 of the line. The Readline @code{vi} mode behaves as specified in
1375 the @sc{posix} 1003.2 standard.
1378 In order to switch interactively between @code{emacs} and @code{vi}
1379 editing modes, use the @samp{set -o emacs} and @samp{set -o vi}
1380 commands (@pxref{The Set Builtin}).
1382 @ifclear BashFeatures
1383 In order to switch interactively between @code{emacs} and @code{vi}
1384 editing modes, use the command @kbd{M-C-j} (bound to emacs-editing-mode
1385 when in @code{vi} mode and to vi-editing-mode in @code{emacs} mode).
1387 The Readline default is @code{emacs} mode.
1389 When you enter a line in @code{vi} mode, you are already placed in
1390 `insertion' mode, as if you had typed an @samp{i}. Pressing @key{ESC}
1391 switches you into `command' mode, where you can edit the text of the
1392 line with the standard @code{vi} movement keys, move to previous
1393 history lines with @samp{k} and subsequent lines with @samp{j}, and
1397 @node Programmable Completion
1398 @section Programmable Completion
1399 @cindex programmable completion
1401 When word completion is attempted for an argument to a command for
1402 which a completion specification (a @var{compspec}) has been defined
1403 using the @code{complete} builtin (@pxref{Programmable Completion Builtins}),
1404 the programmable completion facilities are invoked.
1406 First, the command name is identified.
1407 If a compspec has been defined for that command, the
1408 compspec is used to generate the list of possible completions for the word.
1409 If the command word is a full pathname, a compspec for the full
1410 pathname is searched for first.
1411 If no compspec is found for the full pathname, an attempt is made to
1412 find a compspec for the portion following the final slash.
1414 Once a compspec has been found, it is used to generate the list of
1416 If a compspec is not found, the default Bash completion
1417 described above (@pxref{Commands For Completion}) is performed.
1419 First, the actions specified by the compspec are used.
1420 Only matches which are prefixed by the word being completed are
1422 When the @option{-f} or @option{-d} option is used for filename or
1423 directory name completion, the shell variable @env{FIGNORE} is
1424 used to filter the matches.
1425 @xref{Bash Variables}, for a description of @env{FIGNORE}.
1427 Any completions specified by a filename expansion pattern to the
1428 @option{-G} option are generated next.
1429 The words generated by the pattern need not match the word being completed.
1430 The @env{GLOBIGNORE} shell variable is not used to filter the matches,
1431 but the @env{FIGNORE} shell variable is used.
1433 Next, the string specified as the argument to the @option{-W} option
1435 The string is first split using the characters in the @env{IFS}
1436 special variable as delimiters.
1437 Shell quoting is honored.
1438 Each word is then expanded using
1439 brace expansion, tilde expansion, parameter and variable expansion,
1440 command substitution, arithmetic expansion, and pathname expansion,
1441 as described above (@pxref{Shell Expansions}).
1442 The results are split using the rules described above
1443 (@pxref{Word Splitting}).
1444 The results of the expansion are prefix-matched against the word being
1445 completed, and the matching words become the possible completions.
1447 After these matches have been generated, any shell function or command
1448 specified with the @option{-F} and @option{-C} options is invoked.
1449 When the command or function is invoked, the @env{COMP_LINE} and
1450 @env{COMP_POINT} variables are assigned values as described above
1451 (@pxref{Bash Variables}).
1452 If a shell function is being invoked, the @env{COMP_WORDS} and
1453 @env{COMP_CWORD} variables are also set.
1454 When the function or command is invoked, the first argument is the
1455 name of the command whose arguments are being completed, the
1456 second argument is the word being completed, and the third argument
1457 is the word preceding the word being completed on the current command line.
1458 No filtering of the generated completions against the word being completed
1459 is performed; the function or command has complete freedom in generating
1462 Any function specified with @option{-F} is invoked first.
1463 The function may use any of the shell facilities, including the
1464 @code{compgen} builtin described below
1465 (@pxref{Programmable Completion Builtins}), to generate the matches.
1466 It must put the possible completions in the @env{COMPREPLY} array
1469 Next, any command specified with the @option{-C} option is invoked
1470 in an environment equivalent to command substitution.
1471 It should print a list of completions, one per line, to
1472 the standard output.
1473 Backslash may be used to escape a newline, if necessary.
1475 After all of the possible completions are generated, any filter
1476 specified with the @option{-X} option is applied to the list.
1477 The filter is a pattern as used for pathname expansion; a @samp{&}
1478 in the pattern is replaced with the text of the word being completed.
1479 A literal @samp{&} may be escaped with a backslash; the backslash
1480 is removed before attempting a match.
1481 Any completion that matches the pattern will be removed from the list.
1482 A leading @samp{!} negates the pattern; in this case any completion
1483 not matching the pattern will be removed.
1485 Finally, any prefix and suffix specified with the @option{-P} and @option{-S}
1486 options are added to each member of the completion list, and the result is
1487 returned to the Readline completion code as the list of possible
1490 If the previously-applied actions do not generate any matches, and the
1491 @option{-o dirnames} option was supplied to @code{complete} when the
1492 compspec was defined, directory name completion is attempted.
1494 By default, if a compspec is found, whatever it generates is returned to
1495 the completion code as the full set of possible completions.
1496 The default Bash completions are not attempted, and the Readline default
1497 of filename completion is disabled.
1498 If the @option{-o default} option was supplied to @code{complete} when the
1499 compspec was defined, Readline's default completion will be performed
1500 if the compspec generates no matches.
1502 @node Programmable Completion Builtins
1503 @section Programmable Completion Builtins
1504 @cindex completion builtins
1506 Two builtin commands are available to manipulate the programmable completion
1513 @code{compgen [@var{option}] [@var{word}]}
1516 Generate possible completion matches for @var{word} according to
1517 the @var{option}s, which may be any option accepted by the
1519 builtin with the exception of @option{-p} and @option{-r}, and write
1520 the matches to the standard output.
1521 When using the @option{-F} or @option{-C} options, the various shell variables
1522 set by the programmable completion facilities, while available, will not
1525 The matches will be generated in the same way as if the programmable
1526 completion code had generated them directly from a completion specification
1527 with the same flags.
1528 If @var{word} is specified, only those completions matching @var{word}
1531 The return value is true unless an invalid option is supplied, or no
1532 matches were generated.
1537 @code{complete [-abcdefjkvu] [-o @var{comp-option}] [-A @var{action}] [-G @var{globpat}] [-W @var{wordlist}]
1538 [-P @var{prefix}] [-S @var{suffix}] [-X @var{filterpat}] [-F @var{function}]
1539 [-C @var{command}] @var{name} [@var{name} @dots{}]}
1540 @code{complete -pr [@var{name} @dots{}]}
1543 Specify how arguments to each @var{name} should be completed.
1544 If the @option{-p} option is supplied, or if no options are supplied, existing
1545 completion specifications are printed in a way that allows them to be
1547 The @option{-r} option removes a completion specification for
1548 each @var{name}, or, if no @var{name}s are supplied, all
1549 completion specifications.
1551 The process of applying these completion specifications when word completion
1552 is attempted is described above (@pxref{Programmable Completion}).
1554 Other options, if specified, have the following meanings.
1555 The arguments to the @option{-G}, @option{-W}, and @option{-X} options
1556 (and, if necessary, the @option{-P} and @option{-S} options)
1557 should be quoted to protect them from expansion before the
1558 @code{complete} builtin is invoked.
1562 @item -o @var{comp-option}
1563 The @var{comp-option} controls several aspects of the compspec's behavior
1564 beyond the simple generation of completions.
1565 @var{comp-option} may be one of:
1570 Use readline's default completion if the compspec generates no matches.
1573 Perform directory name completion if the compspec generates no matches.
1576 Tell Readline that the compspec generates filenames, so it can perform any
1577 filename\-specific processing (like adding a slash to directory names or
1578 suppressing trailing spaces). This option is intended to be used with
1579 shell functions specified with @option{-F}.
1582 @item -A @var{action}
1583 The @var{action} may be one of the following to generate a list of possible
1588 Alias names. May also be specified as @option{-a}.
1591 Array variable names.
1594 Readline key binding names (@pxref{Bindable Readline Commands}).
1597 Names of shell builtin commands. May also be specified as @option{-b}.
1600 Command names. May also be specified as @option{-c}.
1603 Directory names. May also be specified as @option{-d}.
1606 Names of disabled shell builtins.
1609 Names of enabled shell builtins.
1612 Names of exported shell variables. May also be specified as @option{-e}.
1615 File names. May also be specified as @option{-f}.
1618 Names of shell functions.
1621 Help topics as accepted by the @code{help} builtin (@pxref{Bash Builtins}).
1624 Hostnames, as taken from the file specified by the
1625 @env{HOSTFILE} shell variable (@pxref{Bash Variables}).
1628 Job names, if job control is active. May also be specified as @option{-j}.
1631 Shell reserved words. May also be specified as @option{-k}.
1634 Names of running jobs, if job control is active.
1637 Valid arguments for the @option{-o} option to the @code{set} builtin
1638 (@pxref{The Set Builtin}).
1641 Shell option names as accepted by the @code{shopt} builtin
1642 (@pxref{Bash Builtins}).
1648 Names of stopped jobs, if job control is active.
1651 User names. May also be specified as @option{-u}.
1654 Names of all shell variables. May also be specified as @option{-v}.
1657 @item -G @var{globpat}
1658 The filename expansion pattern @var{globpat} is expanded to generate
1659 the possible completions.
1661 @item -W @var{wordlist}
1662 The @var{wordlist} is split using the characters in the
1663 @env{IFS} special variable as delimiters, and each resultant word
1665 The possible completions are the members of the resultant list which
1666 match the word being completed.
1668 @item -C @var{command}
1669 @var{command} is executed in a subshell environment, and its output is
1670 used as the possible completions.
1672 @item -F @var{function}
1673 The shell function @var{function} is executed in the current shell
1675 When it finishes, the possible completions are retrieved from the value
1676 of the @env{COMPREPLY} array variable.
1678 @item -X @var{filterpat}
1679 @var{filterpat} is a pattern as used for filename expansion.
1680 It is applied to the list of possible completions generated by the
1681 preceding options and arguments, and each completion matching
1682 @var{filterpat} is removed from the list.
1683 A leading @samp{!} in @var{filterpat} negates the pattern; in this
1684 case, any completion not matching @var{filterpat} is removed.
1686 @item -P @var{prefix}
1687 @var{prefix} is added at the beginning of each possible completion
1688 after all other options have been applied.
1690 @item -S @var{suffix}
1691 @var{suffix} is appended to each possible completion
1692 after all other options have been applied.
1695 The return value is true unless an invalid option is supplied, an option
1696 other than @option{-p} or @option{-r} is supplied without a @var{name}
1697 argument, an attempt is made to remove a completion specification for
1698 a @var{name} for which no specification exists, or
1699 an error occurs adding a completion specification.