GNU Readline Library

]> GNU Readline Library This manual describes the end user interface of the GNU Readline Library(version 5.1-beta1, 11 November 2005), a library which aids in theconsistency of user interface across discrete programs which providea command line interface.Copyright © 1988-2005 Free Software Foundation, Inc.Permission is granted to make and distribute verbatim copies ofthis manual provided the copyright notice and this permission noticeare preserved on all copies. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover texts being “A GNU Manual,” and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License.” (a) The FSF's Back-Cover Text is: “You have freedom to copy and modify this GNU Manual, like GNU software. Copies published by the Free Software Foundation raise funds for GNU development.” GNU Readline Library This document describes the end user interface of the GNU Readline Library, a utility which aids in the consistency of user interface across discrete programs which provide a command line interface. <setfilename>rluser.info</setfilename> Command Line Editing This chapter describes the basic features of the gnu command line editing interface. Introduction to Line Editing The following paragraphs describe the notation used to represent keystrokes. The text C-k is read as `Control-K' and describes the character produced when the k key is pressed while the Control key is depressed. The text M-k is read as `Meta-K' and describes the character produced when the Meta key (if you have one) is depressed, and the k key is pressed. The Meta key is labeled ALT on many keyboards. On keyboards with two keys labeled ALT (usually to either side of the space bar), the ALT on the left side is generally set to work as a Meta key. The ALT key on the right may also be configured to work as a Meta key or may be configured as some other modifier, such as a Compose key for typing accented characters. If you do not have a Meta or ALT key, or another key working as a Meta key, the identical keystroke can be generated by typing ESC first, and then typing k. Either process is known as metafying the k key. The text M-C-k is read as `Meta-Control-k' and describes the character produced by metafying C-k. In addition, several keys have their own names. Specifically, DEL, ESC, LFD, SPC, RET, and TAB all stand for themselves when seen in this text, or in an init file (see ). If your keyboard lacks a LFD key, typing C-j will produce the desired character. The RET key may be labeled Return or Enter on some keyboards. Readline Interaction interaction, readline Often during an interactive session you type in a long line of text, only to notice that the first word on the line is misspelled. The Readline library gives you a set of commands for manipulating the text as you type it in, allowing you to just fix your typo, and not forcing you to retype the majority of the line. Using these editing commands, you move the cursor to the place that needs correction, and delete or insert the text of the corrections. Then, when you are satisfied with the line, you simply press RET. You do not have to be at the end of the line to press RET; the entire line is accepted regardless of the location of the cursor within the line. Readline Bare Essentials notation, readline command editing editing command lines In order to enter characters into the line, simply type them. The typed character appears where the cursor was, and then the cursor moves one space to the right. If you mistype a character, you can use your erase character to back up and delete the mistyped character. Sometimes you may mistype a character, and not notice the error until you have typed several other characters. In that case, you can type C-b to move the cursor to the left, and then correct your mistake. Afterwards, you can move the cursor to the right with C-f. When you add text in the middle of a line, you will notice that characters to the right of the cursor are `pushed over' to make room for the text that you have inserted. Likewise, when you delete text behind the cursor, characters to the right of the cursor are `pulled back' to fill in the blank space created by the removal of the text. A list of the bare essentials for editing the text of an input line follows. C-b Move back one character. C-f Move forward one character. DEL or Backspace Delete the character to the left of the cursor. C-d Delete the character underneath the cursor. Printing characters Insert the character into the line at the cursor. C-_ or C-x C-u Undo the last editing command. You can undo all the way back to anempty line. (Depending on your configuration, the Backspace key be set to delete the character to the left of the cursor and the DEL key set to delete the character underneath the cursor, like C-d, rather than the character to the left of the cursor.) Readline Movement Commands The above table describes the most basic keystrokes that you need in order to do editing of the input line. For your convenience, many other commands have been added in addition to C-b, C-f, C-d, and DEL. Here are some commands for moving more rapidly about the line. C-a Move to the start of the line. C-e Move to the end of the line. M-f Move forward a word, where a word is composed of letters and digits. M-b Move backward a word. C-l Clear the screen, reprinting the current line at the top. Notice how C-f moves forward a character, while M-f moves forward a word. It is a loose convention that control keystrokes operate on characters while meta keystrokes operate on words. Readline Killing Commands killing text yanking text Killing text means to delete the text from the line, but to save it away for later use, usually by yanking (re-inserting) it back into the line. (`Cut' and `paste' are more recent jargon for `kill' and `yank'.) If the description for a command says that it `kills' text, then you can be sure that you can get the text back in a different (or the same) place later. When you use a kill command, the text is saved in a kill-ring. Any number of consecutive kills save all of the killed text together, so that when you yank it back, you get it all. The kill ring is not line specific; the text that you killed on a previously typed line is available to be yanked back later, when you are typing another line. kill ring Here is the list of commands for killing text. C-k Kill the text from the current cursor position to the end of the line. M-d Kill from the cursor to the end of the current word, or, if betweenwords, to the end of the next word.Word boundaries are the same as those used by M-f. M-DEL Kill from the cursor the start of the current word, or, if betweenwords, to the start of the previous word.Word boundaries are the same as those used by M-b. C-w Kill from the cursor to the previous whitespace. This is different thanM-DEL because the word boundaries differ. Here is how to yank the text back into the line. Yanking means to copy the most-recently-killed text from the kill buffer. C-y Yank the most recently killed text back into the buffer at the cursor. M-y Rotate the kill-ring, and yank the new top. You can only do this ifthe prior command is C-y or M-y. Readline Arguments You can pass numeric arguments to Readline commands. Sometimes the argument acts as a repeat count, other times it is the sign of the argument that is significant. If you pass a negative argument to a command which normally acts in a forward direction, that command will act in a backward direction. For example, to kill text back to the start of the line, you might type ‘M-- C-k’. The general way to pass numeric arguments to a command is to type meta digits before the command. If the first `digit' typed is a minus sign (‘-’), then the sign of the argument will be negative. Once you have typed one meta digit to get the argument started, you can type the remainder of the digits, and then the command. For example, to give the C-d command an argument of 10, you could type ‘M-1 0 C-d’, which will delete the next ten characters on the input line. Searching for Commands in the History Readline provides commands for searching through the command history for lines containing a specified string. There are two search modes: incremental and non-incremental. Incremental searches begin before the user has finished typing the search string. As each character of the search string is typed, Readline displays the next entry from the history matching the string typed so far. An incremental search requires only as many characters as needed to find the desired history entry. To search backward in the history for a particular string, type C-r. Typing C-s searches forward through the history. The characters present in the value of the isearch-terminators variable are used to terminate an incremental search. If that variable has not been assigned a value, the ESC and C-J characters will terminate an incremental search. C-g will abort an incremental search and restore the original line. When the search is terminated, the history entry containing the search string becomes the current line. To find other matching entries in the history list, type C-r or C-s as appropriate. This will search backward or forward in the history for the next entry matching the search string typed so far. Any other key sequence bound to a Readline command will terminate the search and execute that command. For instance, a RET will terminate the search and accept the line, thereby executing the command from the history list. A movement command will terminate the search, make the last line found the current line, and begin editing. Readline remembers the last incremental search string. If two C-rs are typed without any intervening characters defining a new search string, any remembered search string is used. Non-incremental searches read the entire search string before starting to search for matching history lines. The search string may be typed by the user or be part of the contents of the current line. Readline Init File initialization file, readline Although the Readline library comes with a set of Emacs-like keybindings installed by default, it is possible to use a different set of keybindings. Any user can customize programs that use Readline by putting commands in an inputrc file, conventionally in his home directory. The name of this file is taken from the value of the environment variable INPUTRC. If that variable is unset, the default is ~/.inputrc. When a program which uses the Readline library starts up, the init file is read, and the key bindings are set. In addition, the C-x C-r command re-reads this init file, thus incorporating any changes that you might have made to it. Readline Init File Syntax There are only a few basic constructs allowed in the Readline init file. Blank lines are ignored. Lines beginning with a ‘#’ are comments. Lines beginning with a ‘$’ indicate conditional constructs (see ). Other lines denote variable settings and key bindings. Variable Settings You can modify the run-time behavior of Readline byaltering the values of variables in Readlineusing the set command within the init file.The syntax is simple: set variable value Here, for example, is how tochange from the default Emacs-like key binding to usevi line editing commands: set editing-mode vi Variable names and values, where appropriate, are recognized without regardto case. Unrecognized variable names are ignored.Boolean variables (those that can be set to on or off) are set to on ifthe value is null or empty, on (case-insensitive), or 1. Any othervalue results in the variable being set to off.A great deal of run-time behavior is changeable with the followingvariables. variables, readline bell-style bell-styleControls what happens when Readline wants to ring the terminal bell.If set to ‘none’, Readline never rings the bell. If set to‘visible’, Readline uses a visible bell if one is available.If set to ‘audible’ (the default), Readline attempts to ringthe terminal's bell. bind-tty-special-chars bind-tty-special-charsIf set to ‘on’, Readline attempts to bind the control characterstreated specially by the kernel's terminal driver to their Readlineequivalents. comment-begin comment-beginThe string to insert at the beginning of the line when theinsert-comment command is executed. The default valueis "#". completion-ignore-case If set to ‘on’, Readline performs filename matching and completionin a case-insensitive fashion.The default value is ‘off’. completion-query-items completion-query-itemsThe number of possible completions that determines when the user isasked whether the list of possibilities should be displayed.If the number of possible completions is greater than this value,Readline will ask the user whether or not he wishes to viewthem; otherwise, they are simply listed.This variable must be set to an integer value greater than or equal to 0.A negative value means Readline should never ask.The default limit is 100. convert-meta convert-metaIf set to ‘on’, Readline will convert characters with theeighth bit set to an ascii key sequence by stripping the eighthbit and prefixing an ESC character, converting them to ameta-prefixed key sequence. The default value is ‘on’. disable-completion disable-completionIf set to ‘On’, Readline will inhibit word completion.Completion characters will be inserted into the line as if they hadbeen mapped to self-insert. The default is ‘off’. editing-mode editing-modeThe editing-mode variable controls which default set ofkey bindings is used. By default, Readline starts up in Emacs editingmode, where the keystrokes are most similar to Emacs. This variable can beset to either ‘emacs’ or ‘vi’. enable-keypad enable-keypadWhen set to ‘on’, Readline will try to enable the applicationkeypad when it is called. Some systems need this to enable thearrow keys. The default is ‘off’. expand-tilde expand-tildeIf set to ‘on’, tilde expansion is performed when Readlineattempts word completion. The default is ‘off’. history-preserve-point history-preserve-pointIf set to ‘on’, the history code attempts to place point at thesame location on each history line retrieved with previous-historyor next-history. The default is ‘off’. horizontal-scroll-mode horizontal-scroll-modeThis variable can be set to either ‘on’ or ‘off’. Setting itto ‘on’ means that the text of the lines being edited will scrollhorizontally on a single screen line when they are longer than the widthof the screen, instead of wrapping onto a new screen line. By default,this variable is set to ‘off’. input-meta input-meta meta-flagIf set to ‘on’, Readline will enable eight-bit input (itwill not clear the eighth bit in the characters it reads),regardless of what the terminal claims it can support. Thedefault value is ‘off’. The name meta-flag is asynonym for this variable. isearch-terminators isearch-terminatorsThe string of characters that should terminate an incremental search withoutsubsequently executing the character as a command (see ).If this variable has not been given a value, the characters ESC andC-J will terminate an incremental search. keymap keymapSets Readline's idea of the current keymap for key binding commands.Acceptable keymap names areemacs,emacs-standard,emacs-meta,emacs-ctlx,vi,vi-move,vi-command, andvi-insert.vi is equivalent to vi-command; emacs isequivalent to emacs-standard. The default value is emacs.The value of the editing-mode variable also affects thedefault keymap. mark-directories If set to ‘on’, completed directory names have a slashappended. The default is ‘on’. mark-modified-lines mark-modified-linesThis variable, when set to ‘on’, causes Readline to display anasterisk (‘*’) at the start of history lines which have been modified.This variable is ‘off’ by default. mark-symlinked-directories mark-symlinked-directoriesIf set to ‘on’, completed names which are symbolic linksto directories have a slash appended (subject to the value ofmark-directories).The default is ‘off’. match-hidden-files match-hidden-filesThis variable, when set to ‘on’, causes Readline to match files whosenames begin with a ‘.’ (hidden files) when performing filenamecompletion, unless the leading ‘.’ issupplied by the user in the filename to be completed.This variable is ‘on’ by default. output-meta output-metaIf set to ‘on’, Readline will display characters with theeighth bit set directly rather than as a meta-prefixed escapesequence. The default is ‘off’. page-completions page-completionsIf set to ‘on’, Readline uses an internal more-like pagerto display a screenful of possible completions at a time.This variable is ‘on’ by default. print-completions-horizontally If set to ‘on’, Readline will display completions with matchessorted horizontally in alphabetical order, rather than down the screen.The default is ‘off’. show-all-if-ambiguous show-all-if-ambiguousThis alters the default behavior of the completion functions. Ifset to ‘on’,words which have more than one possible completion cause thematches to be listed immediately instead of ringing the bell.The default value is ‘off’. show-all-if-unmodified show-all-if-unmodifiedThis alters the default behavior of the completion functions ina fashion similar to show-all-if-ambiguous.If set to ‘on’,words which have more than one possible completion without anypossible partial completion (the possible completions don't sharea common prefix) cause the matches to be listed immediately insteadof ringing the bell.The default value is ‘off’. visible-stats visible-statsIf set to ‘on’, a character denoting a file's typeis appended to the filename when listing possiblecompletions. The default is ‘off’. Key Bindings The syntax for controlling key bindings in the init file issimple. First you need to find the name of the command that youwant to change. The following sections contain tables of the commandname, the default keybinding, if any, and a short description of whatthe command does.Once you know the name of the command, simply place on a linein the init file the name of the keyyou wish to bind the command to, a colon, and then the name of thecommand. The name of the keycan be expressed in different ways, depending on what you find mostcomfortable.In addition to command names, readline allows keys to be boundto a string that is inserted when the key is pressed (a macro). keyname: function-name or macro keyname is the name of a key spelled out in English. For example: Control-u: universal-argument Meta-Rubout: backward-kill-word Control-o: "> output" In the above example, C-u is bound to the functionuniversal-argument,M-DEL is bound to the function backward-kill-word, andC-o is bound to run the macroexpressed on the right hand side (that is, to insert the text‘> output’ into the line).A number of symbolic character names are recognized whileprocessing this key binding syntax:DEL,ESC,ESCAPE,LFD,NEWLINE,RET,RETURN,RUBOUT,SPACE,SPC,andTAB. "keyseq": function-name or macro keyseq differs from keyname above in that stringsdenoting an entire key sequence can be specified, by placingthe key sequence in double quotes. Some gnu Emacs style keyescapes can be used, as in the following example, but thespecial character names are not recognized. "\C-u": universal-argument "\C-x\C-r": re-read-init-file "\e[11~": "Function Key 1" In the above example, C-u is again bound to the functionuniversal-argument (just as it was in the first example),‘C-x C-r’ is bound to the function re-read-init-file,and ‘ESC [ 1 1 ~’ is bound to insertthe text ‘Function Key 1’. The following gnu Emacs style escape sequences are available whenspecifying key sequences: \C- control prefix \M- meta prefix \e an escape character \\ backslash \" ", a double quotation mark \' ', a single quote or apostrophe In addition to the gnu Emacs style escape sequences, a secondset of backslash escapes is available: \a alert (bell) \b backspace \d delete \f form feed \n newline \r carriage return \t horizontal tab \v vertical tab \nnn the eight-bit character whose value is the octal value nnn(one to three digits) \xHH the eight-bit character whose value is the hexadecimal value HH(one or two hex digits) When entering the text of a macro, single or double quotes mustbe used to indicate a macro definition.Unquoted text is assumed to be a function name.In the macro body, the backslash escapes described above are expanded.Backslash will quote any other character in the macro text,including ‘"’ and ‘'’.For example, the following binding will make ‘C-x \’insert a single ‘\’ into the line: "\C-x\\": "\\" Conditional Init Constructs Readline implements a facility similar in spirit to the conditional compilation features of the C preprocessor which allows key bindings and variable settings to be performed as the result of tests. There are four parser directives used. $if The $if construct allows bindings to be made based on theediting mode, the terminal being used, or the application usingReadline. The text of the test extends to the end of the line;no characters are required to isolate it. mode The mode= form of the $if directive is used to testwhether Readline is in emacs or vi mode.This may be used in conjunctionwith the ‘set keymap’ command, for instance, to set bindings inthe emacs-standard and emacs-ctlx keymaps only ifReadline is starting out in emacs mode. term The term= form may be used to include terminal-specifickey bindings, perhaps to bind the key sequences output by theterminal's function keys. The word on the right side of the‘=’ is tested against both the full name of the terminal andthe portion of the terminal name before the first ‘-’. Thisallows sun to match both sun and sun-cmd,for instance. application The application construct is used to includeapplication-specific settings. Each program using the Readlinelibrary sets the application name, and you can test fora particular value.This could be used to bind key sequences to functions useful fora specific program. For instance, the following command adds akey sequence that quotes the current or previous word in Bash: $if Bash # Quote the current or previous word "\C-xq": "\eb\"\ef\"" $endif $endif This command, as seen in the previous example, terminates an$if command. $else Commands in this branch of the $if directive are executed ifthe test fails. $include This directive takes a single filename as an argument and reads commandsand bindings from that file.For example, the following directive reads from /etc/inputrc: $include /etc/inputrc Sample Init File Here is an example of an inputrc file. This illustrates key binding, variable assignment, and conditional syntax. # This file controls the behaviour of line input editing for # programs that use the GNU Readline library. Existing # programs include FTP, Bash, and GDB. # # You can re-read the inputrc file with C-x C-r. # Lines beginning with '#' are comments. # # First, include any systemwide bindings and variable # assignments from /etc/Inputrc $include /etc/Inputrc # # Set various bindings for emacs mode. set editing-mode emacs $if mode=emacs Meta-Control-h: backward-kill-word Text after the function name is ignored # # Arrow keys in keypad mode # #"\M-OD": backward-char #"\M-OC": forward-char #"\M-OA": previous-history #"\M-OB": next-history # # Arrow keys in ANSI mode # "\M-[D": backward-char "\M-[C": forward-char "\M-[A": previous-history "\M-[B": next-history # # Arrow keys in 8 bit keypad mode # #"\M-\C-OD": backward-char #"\M-\C-OC": forward-char #"\M-\C-OA": previous-history #"\M-\C-OB": next-history # # Arrow keys in 8 bit ANSI mode # #"\M-\C-[D": backward-char #"\M-\C-[C": forward-char #"\M-\C-[A": previous-history #"\M-\C-[B": next-history C-q: quoted-insert $endif # An old-style binding. This happens to be the default. TAB: complete # Macros that are convenient for shell interaction $if Bash # edit the path "\C-xp": "PATH=${PATH}\e\C-e\C-a\ef\C-f" # prepare to type a quoted word -- # insert open and close double quotes # and move to just after the open quote "\C-x\"": "\"\"\C-b" # insert a backslash (testing backslash escapes # in sequences and macros) "\C-x\\": "\\" # Quote the current or previous word "\C-xq": "\eb\"\ef\"" # Add a binding to refresh the line, which is unbound "\C-xr": redraw-current-line # Edit variable on current line. "\M-\C-v": "\C-a\C-k$\C-y\M-\C-e\C-a\C-y=" $endif # use a visible bell if one is available set bell-style visible # don't strip characters to 7 bits when reading set input-meta on # allow iso-latin1 characters to be inserted rather # than converted to prefix-meta sequences set convert-meta off # display characters with the eighth bit set directly # rather than as meta-prefixed characters set output-meta on # if there are more than 150 possible completions for # a word, ask the user if he wants to see all of them set completion-query-items 150 # For FTP $if Ftp "\C-xg": "get \M-?" "\C-xt": "put \M-?" "\M-.": yank-last-arg $endif Bindable Readline Commands This section describes Readline commands that may be bound to key sequences. Command names without an accompanying key sequence are unbound by default. In the following descriptions, point refers to the current cursor position, and mark refers to a cursor position saved by the set-mark command. The text between the point and mark is referred to as the region. Commands For Moving beginning-of-line (C-a) Move to the start of the current line. end-of-line (C-e) Move to the end of the line. forward-char (C-f) Move forward a character. backward-char (C-b) Move back a character. forward-word (M-f) Move forward to the end of the next word. Words are composed ofletters and digits. backward-word (M-b) Move back to the start of the current or previous word. Words arecomposed of letters and digits. clear-screen (C-l) Clear the screen and redraw the current line,leaving the current line at the top of the screen. redraw-current-line () Refresh the current line. By default, this is unbound. Commands For Manipulating The History accept-line (Newline or Return) Accept the line regardless of where the cursor is.If this line isnon-empty, it may be added to the history list for future recall withadd_history().If this line is a modified history line, the history line is restoredto its original state. previous-history (C-p) Move `back' through the history list, fetching the previous command. next-history (C-n) Move `forward' through the history list, fetching the next command. beginning-of-history (M-<) Move to the first line in the history. end-of-history (M->) Move to the end of the input history, i.e., the line currentlybeing entered. reverse-search-history (C-r) Search backward starting at the current line and moving `up' throughthe history as necessary. This is an incremental search. forward-search-history (C-s) Search forward starting at the current line and moving `down' throughthe the history as necessary. This is an incremental search. non-incremental-reverse-search-history (M-p) Search backward starting at the current line and moving `up'through the history as necessary using a non-incremental searchfor a string supplied by the user. non-incremental-forward-search-history (M-n) Search forward starting at the current line and moving `down'through the the history as necessary using a non-incremental searchfor a string supplied by the user. history-search-forward () Search forward through the history for the string of charactersbetween the start of the current line and the point.This is a non-incremental search.By default, this command is unbound. history-search-backward () Search backward through the history for the string of charactersbetween the start of the current line and the point. Thisis a non-incremental search. By default, this command is unbound. yank-nth-arg (M-C-y) Insert the first argument to the previous command (usuallythe second word on the previous line) at point.With an argument n,insert the nth word from the previous command (the wordsin the previous command begin with word 0). A negative argumentinserts the nth word from the end of the previous command.Once the argument n is computed, the argument is extractedas if the ‘!n’ history expansion had been specified. yank-last-arg (M-. or M-_) Insert last argument to the previous command (the last word of theprevious history entry). With anargument, behave exactly like yank-nth-arg.Successive calls to yank-last-arg move back through the historylist, inserting the last argument of each line in turn.The history expansion facilities are used to extract the last argument,as if the ‘!$’ history expansion had been specified. Commands For Changing Text delete-char (C-d) Delete the character at point. If point is at thebeginning of the line, there are no characters in the line, andthe last character typed was not bound to delete-char, thenreturn eof. backward-delete-char (Rubout) Delete the character behind the cursor. A numeric argument meansto kill the characters instead of deleting them. forward-backward-delete-char () Delete the character under the cursor, unless the cursor is at theend of the line, in which case the character behind the cursor isdeleted. By default, this is not bound to a key. quoted-insert (C-q or C-v) Add the next character typed to the line verbatim. This ishow to insert key sequences like C-q, for example. tab-insert (M-TAB) Insert a tab character. self-insert (a, b, A, 1, !, …) Insert yourself. transpose-chars (C-t) Drag the character before the cursor forward overthe character at the cursor, moving thecursor forward as well. If the insertion pointis at the end of the line, then thistransposes the last two characters of the line.Negative arguments have no effect. transpose-words (M-t) Drag the word before point past the word after point,moving point past that word as well.If the insertion point is at the end of the line, this transposesthe last two words on the line. upcase-word (M-u) Uppercase the current (or following) word. With a negative argument,uppercase the previous word, but do not move the cursor. downcase-word (M-l) Lowercase the current (or following) word. With a negative argument,lowercase the previous word, but do not move the cursor. capitalize-word (M-c) Capitalize the current (or following) word. With a negative argument,capitalize the previous word, but do not move the cursor. overwrite-mode () Toggle overwrite mode. With an explicit positive numeric argument,switches to overwrite mode. With an explicit non-positive numericargument, switches to insert mode. This command affects onlyemacs mode; vi mode does overwrite differently.Each call to readline() starts in insert mode.In overwrite mode, characters bound to self-insert replacethe text at point rather than pushing the text to the right.Characters bound to backward-delete-char replace the characterbefore point with a space.By default, this command is unbound. Killing And Yanking kill-line (C-k) Kill the text from point to the end of the line. backward-kill-line (C-x Rubout) Kill backward to the beginning of the line. unix-line-discard (C-u) Kill backward from the cursor to the beginning of the current line. kill-whole-line () Kill all characters on the current line, no matter where point is.By default, this is unbound. kill-word (M-d) Kill from point to the end of the current word, or if betweenwords, to the end of the next word.Word boundaries are the same as forward-word. backward-kill-word (M-DEL) Kill the word behind point.Word boundaries are the same as backward-word. unix-word-rubout (C-w) Kill the word behind point, using white space as a word boundary.The killed text is saved on the kill-ring. unix-filename-rubout () Kill the word behind point, using white space and the slash characteras the word boundaries.The killed text is saved on the kill-ring. delete-horizontal-space () Delete all spaces and tabs around point. By default, this is unbound. kill-region () Kill the text in the current region.By default, this command is unbound. copy-region-as-kill () Copy the text in the region to the kill buffer, so it can be yankedright away. By default, this command is unbound. copy-backward-word () Copy the word before point to the kill buffer.The word boundaries are the same as backward-word.By default, this command is unbound. copy-forward-word () Copy the word following point to the kill buffer.The word boundaries are the same as forward-word.By default, this command is unbound. yank (C-y) Yank the top of the kill ring into the buffer at point. yank-pop (M-y) Rotate the kill-ring, and yank the new top. You can only do this ifthe prior command is yank or yank-pop. Specifying Numeric Arguments digit-argument (M-0, M-1, … M--) Add this digit to the argument already accumulating, or start a newargument. M– starts a negative argument. universal-argument () This is another way to specify an argument.If this command is followed by one or more digits, optionally with aleading minus sign, those digits define the argument.If the command is followed by digits, executing universal-argumentagain ends the numeric argument, but is otherwise ignored.As a special case, if this command is immediately followed by acharacter that is neither a digit or minus sign, the argument countfor the next command is multiplied by four.The argument count is initially one, so executing this function thefirst time makes the argument count four, a second time makes theargument count sixteen, and so on.By default, this is not bound to a key. Letting Readline Type For You complete (TAB) Attempt to perform completion on the text before point.The actual completion performed is application-specific.The default is filename completion. possible-completions (M-?) List the possible completions of the text before point. insert-completions (M-*) Insert all completions of the text before point that would havebeen generated by possible-completions. menu-complete () Similar to complete, but replaces the word to be completedwith a single match from the list of possible completions.Repeated execution of menu-complete steps through the listof possible completions, inserting each match in turn.At the end of the list of completions, the bell is rung(subject to the setting of bell-style)and the original text is restored.An argument of n moves n positions forward in the listof matches; a negative argument may be used to move backwardthrough the list.This command is intended to be bound to TAB, but is unboundby default. delete-char-or-list () Deletes the character under the cursor if not at the beginning orend of the line (like delete-char).If at the end of the line, behaves identically topossible-completions.This command is unbound by default. Keyboard Macros start-kbd-macro (C-x () Begin saving the characters typed into the current keyboard macro. end-kbd-macro (C-x )) Stop saving the characters typed into the current keyboard macroand save the definition. call-last-kbd-macro (C-x e) Re-execute the last keyboard macro defined, by making the charactersin the macro appear as if typed at the keyboard. Some Miscellaneous Commands re-read-init-file (C-x C-r) Read in the contents of the inputrc file, and incorporateany bindings or variable assignments found there. abort (C-g) Abort the current editing command andring the terminal's bell (subject to the setting ofbell-style). do-uppercase-version (M-a, M-b, M-x, …) If the metafied character x is lowercase, run the commandthat is bound to the corresponding uppercase character. prefix-meta (ESC) Metafy the next character typed. This is for keyboardswithout a meta key. Typing ‘ESC f’ is equivalent to typingM-f. undo (C-_ or C-x C-u) Incremental undo, separately remembered for each line. revert-line (M-r) Undo all changes made to this line. This is like executing the undocommand enough times to get back to the beginning. tilde-expand (M-~) Perform tilde expansion on the current word. set-mark (C-@) Set the mark to the point. If anumeric argument is supplied, the mark is set to that position. exchange-point-and-mark (C-x C-x) Swap the point with the mark. The current cursor position is set tothe saved position, and the old cursor position is saved as the mark. character-search (C-]) A character is read and point is moved to the next occurrence of thatcharacter. A negative count searches for previous occurrences. character-search-backward (M-C-]) A character is read and point is moved to the previous occurrenceof that character. A negative count searches for subsequentoccurrences. insert-comment (M-#) Without a numeric argument, the value of the comment-beginvariable is inserted at the beginning of the current line.If a numeric argument is supplied, this command acts as a toggle: ifthe characters at the beginning of the line do not match the valueof comment-begin, the value is inserted, otherwisethe characters in comment-begin are deleted from the beginning ofthe line.In either case, the line is accepted as if a newline had been typed. dump-functions () Print all of the functions and their key bindings to theReadline output stream. If a numeric argument is supplied,the output is formatted in such a way that it can be made partof an inputrc file. This command is unbound by default. dump-variables () Print all of the settable variables and their values to theReadline output stream. If a numeric argument is supplied,the output is formatted in such a way that it can be made partof an inputrc file. This command is unbound by default. dump-macros () Print all of the Readline key sequences bound to macros and thestrings they output. If a numeric argument is supplied,the output is formatted in such a way that it can be made partof an inputrc file. This command is unbound by default. emacs-editing-mode (C-e) When in vi command mode, this causes a switch to emacsediting mode. vi-editing-mode (M-C-j) When in emacs editing mode, this causes a switch to viediting mode. Readline vi Mode While the Readline library does not have a full set of vi editing functions, it does contain enough to allow simple editing of the line. The Readline vi mode behaves as specified in the posix 1003.2 standard. In order to switch interactively between emacs and vi editing modes, use the command M-C-j (bound to emacs-editing-mode when in vi mode and to vi-editing-mode in emacs mode). The Readline default is emacs mode. When you enter a line in vi mode, you are already placed in `insertion' mode, as if you had typed an ‘i’. Pressing ESC switches you into `command' mode, where you can edit the text of the line with the standard vi movement keys, move to previous history lines with ‘k’ and subsequent lines with ‘j’, and so forth. Copying This Manual GNU Free Documentation License FDL, GNU Free Documentation License

Version 1.2, November 2002

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