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| READLINE(3) |
FreeBSD Library Functions Manual |
READLINE(3) |
readline - get a line from a user with editing
#include <stdio.h>
#include <readline/readline.h>
#include <readline/history.h>
char *
readline (const char *prompt);
Readline is Copyright (C) 1989-2025 Free Software Foundation,
Inc.
readline reads a line from the terminal and return it,
using prompt as a prompt. If prompt is NULL or the
empty string, readline does not issue a prompt. The line returned is
allocated with malloc(3); the caller must free it when finished. The
line returned has the final newline removed, so only the text of the line
remains. Since it's possible to enter characters into the line while quoting
them to disable any readline editing function they might normally
have, this line may include embedded newlines and other special
characters.
readline offers editing capabilities while the user is
entering the line. By default, the line editing commands are similar to
those of emacs. A vi-style line editing interface is also available.
This manual page describes only the most basic use of
readline. Much more functionality is available; see The GNU
Readline Library and The GNU History Library for additional
information.
readline returns the text of the line read. A blank line
returns the empty string. If EOF is encountered while reading a line,
and the line is empty, readline returns NULL. If an EOF
is read with a non-empty line, it is treated as a newline.
This section uses Emacs-style editing concepts and uses its
notation for keystrokes. Control keys are denoted by C-key, e.g., C-n
means Control-N. Similarly, meta keys are denoted by M-key, so
M-x means Meta-X. The Meta key is often labeled “Alt” or
“Option”.
On keyboards without a Meta key, M-x means ESC
x, i.e., press and release the Escape key, then press and release the
x key, in sequence. This makes ESC the meta prefix. The
combination M-C-x means ESC Control-x: press and release the
Escape key, then press and hold the Control key while pressing the x
key, then release both.
On some keyboards, the Meta key modifier produces characters with
the eighth bit (0200) set. You can use the enable-meta-key variable
to control whether or not it does this, if the keyboard allows it. On many
others, the terminal or terminal emulator converts the metafied key to a key
sequence beginning with ESC as described in the preceding paragraph.
If your Meta key produces a key sequence with the ESC meta
prefix, you can make M-key key bindings you specify (see Readline
Key Bindings below) do the same thing by setting the
force-meta-prefix variable.
Readline commands may be given numeric arguments,
which normally act as a repeat count. Sometimes, however, it is the sign of
the argument that is significant. Passing a negative argument to a command
that acts in the forward direction (e.g., kill-line) makes that
command act in a backward direction. Commands whose behavior with arguments
deviates from this are noted below.
The point is the current cursor position, and mark
refers to a saved cursor position. The text between the point and mark is
referred to as the region.
When a command is described as killing text, the text
deleted is saved for possible future retrieval (yanking). The killed
text is saved in a kill ring. Consecutive kills accumulate the
deleted text into one unit, which can be yanked all at once. Commands which
do not kill text separate the chunks of text on the kill ring.
Readline is customized by putting commands in an
initialization file (the inputrc file). The name of this file is
taken from the value of the INPUTRC environment variable. If that
variable is unset, the default is ~/.inputrc. If that file does not
exist or cannot be read, readline looks for
/usr/local/etc/inputrc. When a program that uses the readline
library starts up, readline reads the initialization file and sets
the key bindings and variables found there, before reading any user
input.
There are only a few basic constructs allowed in the inputrc file.
Blank lines are ignored. Lines beginning with a # are comments. Lines
beginning with a $ indicate conditional constructs. Other lines
denote key bindings and variable settings.
The default key-bindings in this document may be changed using key
binding commands in the inputrc file. Programs that use this library
may add their own commands and bindings.
For example, placing
M-Control-u: universal-argument
or
C-Meta-u: universal-argument
into the inputrc would make M-C-u execute the
readline command universal-argument.
Key bindings may contain the following symbolic character names:
DEL, ESC, ESCAPE, LFD, NEWLINE,
RET, RETURN, RUBOUT (a destructive backspace),
SPACE, SPC, and TAB.
In addition to command names, readline allows keys to be
bound to a string that is inserted when the key is pressed (a macro).
The difference between a macro and a command is that a macro is enclosed in
single or double quotes.
The syntax for controlling key bindings in the inputrc file
is simple. All that is required is the name of the command or the text of a
macro and a key sequence to which it should be bound. The key sequence may
be specified in one of two ways: as a symbolic key name, possibly with
Meta- or Control- prefixes, or as a key sequence composed of
one or more characters enclosed in double quotes. The key sequence and name
are separated by a colon. There can be no whitespace between the name and
the colon.
When using the form 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 function
universal-argument, M-DEL is bound to the function
backward-kill-word, and C-o is bound to run the macro
expressed on the right hand side (that is, to insert the text “>
output” into the line).
In the second form, "keyseq":function-name
or macro, keyseq differs from keyname above in that
strings denoting an entire key sequence may be specified by placing the
sequence within double quotes. Some GNU Emacs style key escapes can be used,
as in the following example, but none of the symbolic character names are
recognized.
"\C-u": universal-argument
"\C-x\C-r": re-read-init-file
"\e[11~": "Function Key 1"
In this example, C-u is again bound to the function
universal-argument. C-x C-r is bound to the function
re-read-init-file, and ESC [ 1 1 ~ is bound to insert the text
“Function Key 1”.
The full set of GNU Emacs style escape sequences available when
specifying key sequences is
- \C-
- A control prefix.
- \M-
- Adding the meta prefix or converting the following character to a meta
character, as described below under force-meta-prefix.
- \e
- An escape character.
- \\
- Backslash.
- \"
- Literal ", a double quote.
- \'
- Literal ', a single quote.
In addition to the GNU Emacs style escape sequences, a second set
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 must be
used to indicate a macro definition. Unquoted text is assumed to be a
function name. The backslash escapes described above are expanded in the
macro body. Backslash quotes any other character in the macro text,
including " and '.
Bash will display or modify the current readline key
bindings with the bind builtin command. The -o emacs or -o
vi options to the set builtin change the editing mode during
interactive use. Other programs using this library provide similar
mechanisms. A user may always edit the inputrc file and have
readline re-read it if a program does not provide any other means to
incorporate new bindings.
Readline has variables that can be used to further
customize its behavior. A variable may be set in the inputrc file
with a statement of the form
Except where noted, readline variables can take the values
On or Off (without regard to case). Unrecognized variable
names are ignored. When readline reads a variable value, empty or
null values, “on” (case-insensitive), and “1”
are equivalent to On. All other values are equivalent to
Off.
The variables and their default values are:
- active-region-start-color
- A string variable that controls the text color and background when
displaying the text in the active region (see the description of
enable-active-region below). This string must not take up any
physical character positions on the display, so it should consist only of
terminal escape sequences. It is output to the terminal before displaying
the text in the active region. This variable is reset to the default value
whenever the terminal type changes. The default value is the string that
puts the terminal in standout mode, as obtained from the terminal's
terminfo description. A sample value might be
“\e[01;33m”.
- active-region-end-color
- A string variable that “undoes” the effects of
active-region-start-color and restores “normal”
terminal display appearance after displaying text in the active region.
This string must not take up any physical character positions on the
display, so it should consist only of terminal escape sequences. It is
output to the terminal after displaying the text in the active region.
This variable is reset to the default value whenever the terminal type
changes. The default value is the string that restores the terminal from
standout mode, as obtained from the terminal's terminfo description. A
sample value might be “\e[0m”.
- bell-style
(audible)
- Controls 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, readline attempts to ring the
terminal's bell.
- bind-tty-special-chars
(On)
- If set to On, readline attempts to bind the control
characters that are treated specially by the kernel's terminal driver to
their readline equivalents. These override the default
readline bindings described here. Type “stty -a” at a
bash prompt to see your current terminal settings, including the
special control characters (usually cchars).
- blink-matching-paren
(Off)
- If set to On, readline attempts to briefly move the cursor
to an opening parenthesis when a closing parenthesis is inserted.
- colored-completion-prefix
(Off)
- If set to On, when listing completions, readline displays
the common prefix of the set of possible completions using a different
color. The color definitions are taken from the value of the
LS_COLORS environment variable. If there is a color definition in
$LS_COLORS for the custom suffix
“readline-colored-completion-prefix”, readline uses
this color for the common prefix instead of its default.
- colored-stats
(Off)
- If set to On, readline displays possible completions using
different colors to indicate their file type. The color definitions are
taken from the value of the LS_COLORS environment variable.
- The string that the readline insert-comment command inserts.
This command is bound to M-# in emacs mode and to # in vi
command mode.
- completion-display-width
(-1)
- The number of screen columns used to display possible matches when
performing completion. The value is ignored if it is less than 0 or
greater than the terminal screen width. A value of 0 causes matches to be
displayed one per line. The default value is -1.
- completion-ignore-case
(Off)
- If set to On, readline performs filename matching and
completion in a case-insensitive fashion.
- completion-map-case
(Off)
- If set to On, and completion-ignore-case is enabled,
readline treats hyphens (-) and underscores (_) as
equivalent when performing case-insensitive filename matching and
completion.
- completion-prefix-display-length
(0)
- The maximum length in characters of the common prefix of a list of
possible completions that is displayed without modification. When set to a
value greater than zero, readline replaces common prefixes longer
than this value with an ellipsis when displaying possible completions. If
a completion begins with a period, and eadline is completing
filenames, it uses three underscores instead of an ellipsis.
- completion-query-items
(100)
- This determines when the user is queried about viewing the number of
possible completions generated by the possible-completions command.
It may be set to any integer value greater than or equal to zero. If the
number of possible completions is greater than or equal to the value of
this variable, readline asks whether or not the user wishes to view
them; otherwise readline simply lists them on the terminal. A zero
value means readline should never ask; negative values are treated
as zero.
- convert-meta
(On)
- If set to On, readline converts characters it reads that
have the eighth bit set to an ASCII key sequence by clearing the eighth
bit and prefixing it with an escape character (converting the character to
have the meta prefix). The default is On, but readline sets
it to Off if the locale contains characters whose encodings may
include bytes with the eighth bit set. This variable is dependent on the
LC_CTYPE locale category, and may change if the locale changes.
This variable also affects key bindings; see the description of
force-meta-prefix below.
- disable-completion
(Off)
- If set to On, readline inhibits word completion. Completion
characters are inserted into the line as if they had been mapped to
self-insert.
- echo-control-characters
(On)
- When set to On, on operating systems that indicate they support it,
readline echoes a character corresponding to a signal generated
from the keyboard.
- editing-mode
(emacs)
- Controls whether readline uses a set of key bindings similar to
Emacs or vi. editing-mode can be set to either
emacs or vi.
- emacs-mode-string
(@)
- If the show-mode-in-prompt variable is enabled, this string is
displayed immediately before the last line of the primary prompt when
emacs editing mode is active. The value is expanded like a key binding, so
the standard set of meta- and control- prefixes and backslash escape
sequences is available. The \1 and \2 escapes begin and end sequences of
non-printing characters, which can be used to embed a terminal control
sequence into the mode string.
- enable-active-region
(On)
- When this variable is set to On, readline allows certain
commands to designate the region as active. When the region is
active, readline highlights the text in the region using the value
of the active-region-start-color variable, which defaults to the
string that enables the terminal's standout mode. The active region shows
the text inserted by bracketed-paste and any matching text found by
incremental and non-incremental history searches.
- enable-bracketed-paste
(On)
- When set to On, readline configures the terminal to insert
each paste into the editing buffer as a single string of characters,
instead of treating each character as if it had been read from the
keyboard. This is called bracketed-paste mode; it prevents
readline from executing any editing commands bound to key sequences
appearing in the pasted text.
- enable-keypad
(Off)
- When set to On, readline tries to enable the application
keypad when it is called. Some systems need this to enable the arrow
keys.
- enable-meta-key
(On)
- When set to On, readline tries to enable any meta modifier
key the terminal claims to support. On many terminals, the Meta key is
used to send eight-bit characters; this variable checks for the terminal
capability that indicates the terminal can enable and disable a mode that
sets the eighth bit of a character (0200) if the Meta key is held down
when the character is typed (a meta character).
- expand-tilde
(Off)
- If set to On, readline performs tilde expansion when it
attempts word completion.
- force-meta-prefix
(Off)
- If set to On, readline modifies its behavior when binding
key sequences containing \M- or Meta- (see Key Bindings above) by
converting a key sequence of the form \M-C or Meta-C to the
two-character sequence ESC C (adding the meta prefix). If
force-meta-prefix is set to Off (the default),
readline uses the value of the convert-meta variable to
determine whether to perform this conversion: if convert-meta is
On, readline performs the conversion described above; if it
is Off, readline converts C to a meta character by
setting the eighth bit (0200).
- history-preserve-point
(Off)
- If set to On, the history code attempts to place point at the same
location on each history line retrieved with previous-history or
next-history.
- history-size
(unset)
- Set the maximum number of history entries saved in the history list. If
set to zero, any existing history entries are deleted and no new entries
are saved. If set to a value less than zero, the number of history entries
is not limited. By default, the number of history entries is not limited.
Setting history-size to a non-numeric value will set the maximum
number of history entries to 500.
- horizontal-scroll-mode
(Off)
- Setting this variable to On makes readline use a single line
for display, scrolling the input horizontally on a single screen line when
it becomes longer than the screen width rather than wrapping to a new
line. This setting is automatically enabled for terminals of height
1.
- input-meta
(Off)
- If set to On, readline enables eight-bit input (that is, it
does not clear the eighth bit in the characters it reads), regardless of
what the terminal claims it can support. The default is Off, but
readline sets it to On if the locale contains characters
whose encodings may include bytes with the eighth bit set. This variable
is dependent on the LC_CTYPE locale category, and its value may
change if the locale changes. The name meta-flag is a synonym for
input-meta.
- isearch-terminators (“C-[C-j”)
- The string of characters that should terminate an incremental search
without subsequently executing the character as a command. If this
variable has not been given a value, the characters ESC and
C-j terminate an incremental search.
- keymap
(emacs)
- Set the current readline keymap. The set of valid keymap names is
emacs, emacs-standard, emacs-meta, emacs-ctlx, vi,
vi-command, and vi-insert. vi is equivalent to
vi-command; emacs is equivalent to emacs-standard.
The default value is emacs; the value of editing-mode also
affects the default keymap.
- keyseq-timeout
(500)
- Specifies the duration readline will wait for a character when
reading an ambiguous key sequence (one that can form a complete key
sequence using the input read so far, or can take additional input to
complete a longer key sequence). If readline does not receive any
input within the timeout, it uses the shorter but complete key sequence.
The value is specified in milliseconds, so a value of 1000 means that
readline will wait one second for additional input. If this
variable is set to a value less than or equal to zero, or to a non-numeric
value, readline waits until another key is pressed to decide which
key sequence to complete.
- mark-directories
(On)
- If set to On, completed directory names have a slash appended.
- mark-modified-lines
(Off)
- If set to On, readline displays history lines that have been
modified with a preceding asterisk (*).
- mark-symlinked-directories
(Off)
- If set to On, completed names which are symbolic links to
directories have a slash appended, subject to the value of
mark-directories.
- match-hidden-files
(On)
- This variable, when set to On, forces readline to match
files whose names begin with a “.” (hidden files) when
performing filename completion. If set to Off, the user must
include the leading “.” in the filename to be
completed.
- If set to On, menu completion displays the common prefix of the
list of possible completions (which may be empty) before cycling through
the list.
- output-meta
(Off)
- If set to On, readline displays characters with the eighth
bit set directly rather than as a meta-prefixed escape sequence. The
default is Off, but readline sets it to On if the
locale contains characters whose encodings may include bytes with the
eighth bit set. This variable is dependent on the LC_CTYPE locale
category, and its value may change if the locale changes.
- page-completions
(On)
- If set to On, readline uses an internal pager resembling
more(1) to display a screenful of possible completions at a
time.
- prefer-visible-bell
- See bell-style.
- print-completions-horizontally
(Off)
- If set to On, readline displays completions with matches
sorted horizontally in alphabetical order, rather than down the
screen.
- revert-all-at-newline
(Off)
- If set to On, readline will undo all changes to history
lines before returning when executing accept-line. By default,
history lines may be modified and retain individual undo lists across
calls to readline().
- search-ignore-case
(Off)
- If set to On, readline performs incremental and
non-incremental history list searches in a case-insensitive fashion.
- show-all-if-ambiguous
(Off)
- This alters the default behavior of the completion functions. If set to
On, words which have more than one possible completion cause the
matches to be listed immediately instead of ringing the bell.
- show-all-if-unmodified
(Off)
- This alters the default behavior of the completion functions in a fashion
similar to show-all-if-ambiguous. If set to On, words which
have more than one possible completion without any possible partial
completion (the possible completions don't share a common prefix) cause
the matches to be listed immediately instead of ringing the bell.
- show-mode-in-prompt
(Off)
- If set to On, add a string to the beginning of the prompt
indicating the editing mode: emacs, vi command, or vi insertion. The mode
strings are user-settable (e.g., emacs-mode-string).
- skip-completed-text
(Off)
- If set to On, this alters the default completion behavior when
inserting a single match into the line. It's only active when performing
completion in the middle of a word. If enabled, readline does not
insert characters from the completion that match characters after point in
the word being completed, so portions of the word following the cursor are
not duplicated.
- vi-cmd-mode-string
((cmd))
- If the show-mode-in-prompt variable is enabled, this string is
displayed immediately before the last line of the primary prompt when vi
editing mode is active and in command mode. The value is expanded like a
key binding, so the standard set of meta- and control- prefixes and
backslash escape sequences is available. The \1 and \2 escapes begin and
end sequences of non-printing characters, which can be used to embed a
terminal control sequence into the mode string.
- vi-ins-mode-string
((ins))
- If the show-mode-in-prompt variable is enabled, this string is
displayed immediately before the last line of the primary prompt when vi
editing mode is active and in insertion mode. The value is expanded like a
key binding, so the standard set of meta- and control- prefixes and
backslash escape sequences is available. The \1 and \2 escapes begin and
end sequences of non-printing characters, which can be used to embed a
terminal control sequence into the mode string.
- visible-stats
(Off)
- If set to On, a character denoting a file's type as reported by
stat(2) is appended to the filename when listing possible
completions.
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 available.
- $if
- The $if construct allows bindings to be made based on the editing
mode, the terminal being used, or the application using readline.
The text of the test, after any comparison operator, extends to the end of
the line; unless otherwise noted, no characters are required to isolate
it.
- mode
- The mode= form of the $if directive is used to test whether
readline is in emacs or vi mode. This may be used in conjunction
with the set keymap command, for instance, to set bindings in the
emacs-standard and emacs-ctlx keymaps only if
readline is starting out in emacs mode.
- term
- The term= form may be used to include terminal-specific key
bindings, perhaps to bind the key sequences output by the terminal's
function keys. The word on the right side of the = is tested
against both the full name of the terminal and the portion of the terminal
name before the first -. This allows xterm to match both
xterm and xterm-256color, for instance.
- version
- The version test may be used to perform comparisons against
specific readline versions. The version expands to the
current readline version. The set of comparison operators includes
=, (and ==), !=, <=, >=,
<, and >. The version number supplied on the right
side of the operator consists of a major version number, an optional
decimal point, and an optional minor version (e.g., 7.1). If the
minor version is omitted, it defaults to 0. The operator may be
separated from the string version and from the version number
argument by whitespace.
- application
- The application construct is used to include application-specific
settings. Each program using the readline library sets the
application name, and an initialization file can test for a
particular value. This could be used to bind key sequences to functions
useful for a specific program. For instance, the following command adds a
key sequence that quotes the current or previous word in bash:
$if Bash
# Quote the current or previous word
"\C-xq": "\eb\"\ef\""
$endif
- variable
- The variable construct provides simple equality tests for
readline variables and values. The permitted comparison operators
are =, ==, and !=. The variable name must be
separated from the comparison operator by whitespace; the operator may be
separated from the value on the right hand side by whitespace. String and
boolean variables may be tested. Boolean variables must be tested against
the values on and off.
- $else
- Commands in this branch of the $if directive are executed if the
test fails.
- $endif
- This command, as seen in the previous example, terminates an $if
command.
- $include
- This directive takes a single filename as an argument and reads commands
and key bindings from that file. For example, the following directive
would read /usr/local/etc/inputrc:
$include /usr/local/etc/inputrc
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. When using emacs editing mode,
type C-r to search backward in the history for a particular string.
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, ESC and C-j terminate an incremental search. C-g
aborts an incremental search and restores 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 searches 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 terminates the
search and executes that command. For instance, a newline terminates the
search and accepts 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, readline uses any remembered search string.
Non-incremental searches read the entire search string before
starting to search for matching history entries. The search string may be
typed by the user or be part of the contents of the current line.
The following is a list of the names of the commands and the
default key sequences to which they are bound. 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. Readline has the concept of an active
region: when the region is active, readline redisplay highlights
the region using the value of the active-region-start-color variable.
The enable-active-region variable turns this on and off. Several
commands set the region to active; those are noted below.
- beginning-of-line
(C-a)
- Move to the start of the current line. This may also be bound to the Home
key on some keyboards.
- end-of-line
(C-e)
- Move to the end of the line. This may also be bound to the End key on some
keyboards.
- forward-char
(C-f)
- Move forward a character. This may also be bound to the right arrow key on
some keyboards.
- backward-char
(C-b)
- Move back a character.
- forward-word
(M-f)
- Move forward to the end of the next word. Words are composed of
alphanumeric characters (letters and digits).
- backward-word
(M-b)
- Move back to the start of the current or previous word. Words are composed
of alphanumeric characters (letters and digits).
- previous-screen-line
- Attempt to move point to the same physical screen column on the previous
physical screen line. This will not have the desired effect if the current
readline line does not take up more than one physical line or if
point is not greater than the length of the prompt plus the screen
width.
- next-screen-line
- Attempt to move point to the same physical screen column on the next
physical screen line. This will not have the desired effect if the current
readline line does not take up more than one physical line or if
the length of the current readline line is not greater than the
length of the prompt plus the screen width.
- clear-display
(M-C-l)
- Clear the screen and, if possible, the terminal's scrollback buffer, then
redraw the current line, leaving the current line at the top of the
screen.
- clear-screen
(C-l)
- Clear the screen, then redraw the current line, leaving the current line
at the top of the screen. With a numeric argument, refresh the current
line without clearing the screen.
- redraw-current-line
- Refresh the current line.
- accept-line
(Newline, Return)
- Accept the line regardless of where the cursor is. If this line is
non-empty, it may be added to the history list for future recall with
add_history(). If the line is a modified history line, restore the
history line to its original state.
- previous-history
(C-p)
- Fetch the previous command from the history list, moving back in the list.
This may also be bound to the up arrow key on some keyboards.
- next-history
(C-n)
- Fetch the next command from the history list, moving forward in the list.
This may also be bound to the down arrow key on some keyboards.
- 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 currently being
entered.
- operate-and-get-next
(C-o)
- Accept the current line for return to the calling application as if a
newline had been entered, and fetch the next line relative to the current
line from the history for editing. A numeric argument, if supplied,
specifies the history entry to use instead of the current line.
- fetch-history
- With a numeric argument, fetch that entry from the history list and make
it the current line. Without an argument, move back to the first entry in
the history list.
- reverse-search-history
(C-r)
- Search backward starting at the current line and moving “up”
through the history as necessary. This is an incremental search. This
command sets the region to the matched text and activates the region.
- forward-search-history
(C-s)
- Search forward starting at the current line and moving
“down” through the history as necessary. This is an
incremental search. This command sets the region to the matched text and
activates the region.
- non-incremental-reverse-search-history
(M-p)
- Search backward through the history starting at the current line using a
non-incremental search for a string supplied by the user. The search
string may match anywhere in a history line.
- non-incremental-forward-search-history
(M-n)
- Search forward through the history using a non-incremental search for a
string supplied by the user. The search string may match anywhere in a
history line.
- history-search-backward
- Search backward through the history for the string of characters between
the start of the current line and the point. The search string must match
at the beginning of a history line. This is a non-incremental search. This
may be bound to the Page Up key on some keyboards.
- history-search-forward
- Search forward through the history for the string of characters between
the start of the current line and the point. The search string must match
at the beginning of a history line. This is a non-incremental search. This
may be bound to the Page Down key on some keyboards.
- history-substring-search-backward
- Search backward through the history for the string of characters between
the start of the current line and the point. The search string may match
anywhere in a history line. This is a non-incremental search.
- history-substring-search-forward
- Search forward through the history for the string of characters between
the start of the current line and the point. The search string may match
anywhere in a history line. This is a non-incremental search.
- yank-nth-arg
(M-C-y)
- Insert the first argument to the previous command (usually the second word
on the previous line) at point. With an argument n, insert the
nth word from the previous command (the words in the previous
command begin with word 0). A negative argument inserts the nth
word from the end of the previous command. Once the argument n is
computed, this uses the history expansion facilities to extract the
nth word, as if the “!n” history expansion had
been specified.
- yank-last-arg
(M-., M-_)
- Insert the last argument to the previous command (the last word of the
previous history entry). With a numeric argument, behave exactly like
yank-nth-arg. Successive calls to yank-last-arg move back
through the history list, inserting the last word (or the word specified
by the argument to the first call) of each line in turn. Any numeric
argument supplied to these successive calls determines the direction to
move through the history. A negative argument switches the direction
through the history (back or forward). This uses the history expansion
facilities to extract the last word, as if the “!$” history
expansion had been specified.
- end-of-file
(usually C-d)
- The character indicating end-of-file as set, for example, by
stty(1). If this character is read when there are no characters on
the line, and point is at the beginning of the line, readline
interprets it as the end of input and returns EOF.
- delete-char
(C-d)
- Delete the character at point. If this function is bound to the same
character as the tty EOF character, as C-d commonly is, see
above for the effects. This may also be bound to the Delete key on some
keyboards.
- backward-delete-char
(Rubout)
- Delete the character behind the cursor. When given a numeric argument,
save the deleted text on the kill ring.
- forward-backward-delete-char
- Delete the character under the cursor, unless the cursor is at the end of
the line, in which case the character behind the cursor is deleted.
- quoted-insert
(C-q, C-v)
- Add the next character typed to the line verbatim. This is how to insert
characters like C-q, for example.
- tab-insert
(M-TAB)
- Insert a tab character.
- self-insert
(a, b, A, 1, !, ...)
- Insert the character typed.
- bracketed-paste-begin
- This function is intended to be bound to the “bracketed
paste” escape sequence sent by some terminals, and such a binding
is assigned by default. It allows readline to insert the pasted
text as a single unit without treating each character as if it had been
read from the keyboard. The pasted characters are inserted as if each one
was bound to self-insert instead of executing any editing
commands.
- Bracketed paste sets the region to the inserted text and activates the
region.
- transpose-chars
(C-t)
- Drag the character before point forward over the character at point,
moving point forward as well. If point is at the end of the line, then
this transposes the two characters before point. 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 point is at the end of the line, this transposes the
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 point.
- downcase-word
(M-l)
- Lowercase the current (or following) word. With a negative argument,
lowercase the previous word, but do not move point.
- capitalize-word
(M-c)
- Capitalize the current (or following) word. With a negative argument,
capitalize the previous word, but do not move point.
- overwrite-mode
- Toggle overwrite mode. With an explicit positive numeric argument,
switches to overwrite mode. With an explicit non-positive numeric
argument, switches to insert mode. This command affects only emacs
mode; vi mode does overwrite differently. Each call to
readline() starts in insert mode.
- In overwrite mode, characters bound to self-insert replace the text
at point rather than pushing the text to the right. Characters bound to
backward-delete-char replace the character before point with a
space. By default, this command is unbound, but may be bound to the Insert
key on some keyboards.
- kill-line
(C-k)
- Kill the text from point to the end of the current line. With a negative
numeric argument, kill backward from the cursor to the beginning of the
line.
- backward-kill-line
(C-x Rubout)
- Kill backward to the beginning of the current line. With a negative
numeric argument, kill forward from the cursor to the end of the
line.
- unix-line-discard
(C-u)
- Kill backward from point to the beginning of the line, saving the killed
text on the kill-ring.
- kill-whole-line
- Kill all characters on the current line, no matter where point is.
- kill-word
(M-d)
- Kill from point to the end of the current word, or if between words, to
the end of the next word. Word boundaries are the same as those used by
forward-word.
- backward-kill-word
(M-Rubout)
- Kill the word behind point. Word boundaries are the same as those used by
backward-word.
- unix-word-rubout
(C-w)
- Kill the word behind point, using white space as a word boundary, saving
the killed text on the kill-ring.
- unix-filename-rubout
- Kill the word behind point, using white space and the slash character as
the word boundaries, saving the killed text on the kill-ring.
- delete-horizontal-space
(M-\)
- Delete all spaces and tabs around point.
- kill-region
- Kill the text in the current region.
- copy-region-as-kill
- Copy the text in the region to the kill buffer, so it can be yanked
immediately.
- copy-backward-word
- Copy the word before point to the kill buffer. The word boundaries are the
same as backward-word.
- copy-forward-word
- Copy the word following point to the kill buffer. The word boundaries are
the same as forward-word.
- 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. Only works following
yank or yank-pop.
- digit-argument
(M-0, M-1, ..., M--)
- Add this digit to the argument already accumulating, or start a new
argument. 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 a leading minus sign, those digits
define the argument. If the command is followed by digits, executing
universal-argument again ends the numeric argument, but is
otherwise ignored. As a special case, if this command is immediately
followed by a character that is neither a digit nor minus sign, the
argument count for the next command is multiplied by four. The argument
count is initially one, so executing this function the first time makes
the argument count four, a second time makes the argument count sixteen,
and so on.
- complete
(TAB)
- Attempt to perform completion on the text before point. The actual
completion performed is application-specific. Bash, for instance,
attempts programmable completion first, otherwise treating the text as a
variable (if the text begins with $), username (if the text begins
with ~), hostname (if the text begins with @), or command
(including aliases, functions, and builtins) in turn. If none of these
produces a match, it falls back to filename completion. Gdb, on the
other hand, allows completion of program functions and variables, and only
attempts filename completion under certain circumstances. The default
readline completion is filename completion.
- possible-completions
(M-?)
- List the possible completions of the text before point. When displaying
completions, readline sets the number of columns used for display
to the value of completion-display-width, the value of the
environment variable COLUMNS, or the screen width, in that
order.
- insert-completions
(M-*)
- Insert all completions of the text before point that would have been
generated by possible-completions, separated by a space.
- Similar to complete, but replaces the word to be completed with a
single match from the list of possible completions. Repeatedly executing
menu-complete steps through the list of possible completions,
inserting each match in turn. At the end of the list of completions,
menu-complete rings the bell (subject to the setting of
bell-style) and restores the original text. An argument of n
moves n positions forward in the list of matches; a negative
argument moves backward through the list. This command is intended to be
bound to TAB, but is unbound by default.
- Identical to menu-complete, but moves backward through the list of
possible completions, as if menu-complete had been given a negative
argument. This command is unbound by default.
- export-completions
- Perform completion on the word before point as described above and write
the list of possible completions to readline's output stream using
the following format, writing information on separate lines:
- the number of matches N;
- the word being completed;
- S:E, where S and E are the start and end
offsets of the word in the readline line buffer; then
- each match, one per line
- If there are no matches, the first line will be “0”, and
this command does not print any output after the S:E. If
there is only a single match, this prints a single line containing it. If
there is more than one match, this prints the common prefix of the
matches, which may be empty, on the first line after the
S:E, then the matches on subsequent lines. In this case,
N will include the first line with the common prefix.
- The user or application should be able to accommodate the possibility of a
blank line. The intent is that the user or application reads N
lines after the line containing S:E to obtain the match
list. This command is unbound by default.
- delete-char-or-list
- Deletes the character under the cursor if not at the beginning or end of
the line (like delete-char). At the end of the line, it behaves
identically to possible-completions. This command is unbound by
default.
- re-read-init-file
(C-x C-r)
- Read in the contents of the inputrc file, and incorporate any
bindings or variable assignments found there.
- abort (C-g)
- Abort the current editing command and ring the terminal's bell (subject to
the setting of bell-style).
- do-lowercase-version
(M-A, M-B, M-x, ...)
- If the metafied character x is uppercase, run the command that is
bound to the corresponding metafied lowercase character. The behavior is
undefined if x is already lowercase.
- prefix-meta
(ESC)
- Metafy the next character typed. ESC f is
equivalent to Meta-f.
- undo (C-_, 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 undo
command enough times to return the line to its initial state.
- tilde-expand
(M-~)
- Perform tilde expansion on the current word.
- set-mark (C-@,
M-<space>)
- Set the mark to the point. If a numeric argument is supplied, set the mark
to that position.
- exchange-point-and-mark
(C-x C-x)
- Swap the point with the mark. Set the current cursor position to the saved
position, then set the mark to the old cursor position.
- character-search
(C-])
- Read a character and move point to the next occurrence of that character.
A negative argument searches for previous occurrences.
- character-search-backward
(M-C-])
- Read a character and move point to the previous occurrence of that
character. A negative argument searches for subsequent occurrences.
- skip-csi-sequence
- Read enough characters to consume a multi-key sequence such as those
defined for keys like Home and End. CSI sequences begin with a Control
Sequence Indicator (CSI), usually ESC [. If this sequence is bound
to “\e[”, keys producing CSI sequences have no effect unless
explicitly bound to a readline command, instead of inserting stray
characters into the editing buffer. This is unbound by default, but
usually bound to ESC [.
- Without a numeric argument, insert the value of the readline
comment-begin variable at the beginning of the current line. If a
numeric argument is supplied, this command acts as a toggle: if the
characters at the beginning of the line do not match the value of
comment-begin, insert the value; otherwise delete the characters in
comment-begin from the beginning of the line. In either case, the
line is accepted as if a newline had been typed. The default value of
comment-begin causes this command to make the current line a shell
comment. If a numeric argument causes the comment character to be removed,
the line will be executed by the shell.
- dump-functions
- Print all of the functions and their key bindings to the readline
output stream. If a numeric argument is supplied, the output is formatted
in such a way that it can be made part of an inputrc file.
- dump-variables
- Print all of the settable variables and their values to the
readline output stream. If a numeric argument is supplied, the
output is formatted in such a way that it can be made part of an
inputrc file.
- dump-macros
- Print all of the readline key sequences bound to macros and the
strings they output to the readline output stream. If a numeric
argument is supplied, the output is formatted in such a way that it can be
made part of an inputrc file.
- execute-named-command
(M-x)
- Read a bindable readline command name from the input and execute
the function to which it's bound, as if the key sequence to which it was
bound appeared in the input. If this function is supplied with a numeric
argument, it passes that argument to the function it executes.
- emacs-editing-mode
(C-e)
- When in vi command mode, this switches readline to
emacs editing mode.
- vi-editing-mode
(M-C-j)
- When in emacs editing mode, this switches to vi editing
mode.
The following is a list of the default emacs and vi bindings.
Characters with the eighth bit set are written as M-<character>, and
are referred to as metafied characters. The printable ASCII
characters not mentioned in the list of emacs standard bindings are bound to
the self-insert function, which just inserts the given character into
the input line. In vi insertion mode, all characters not specifically
mentioned are bound to self-insert. Characters assigned to signal
generation by stty(1) or the terminal driver, such as C-Z or C-C,
retain that function. Upper and lower case metafied characters are bound to
the same function in the emacs mode meta keymap. The remaining characters
are unbound, which causes readline to ring the bell (subject to the
setting of the bell-style variable).
Emacs Standard bindings
"C-@" set-mark
"C-A" beginning-of-line
"C-B" backward-char
"C-D" delete-char
"C-E" end-of-line
"C-F" forward-char
"C-G" abort
"C-H" backward-delete-char
"C-I" complete
"C-J" accept-line
"C-K" kill-line
"C-L" clear-screen
"C-M" accept-line
"C-N" next-history
"C-P" previous-history
"C-Q" quoted-insert
"C-R" reverse-search-history
"C-S" forward-search-history
"C-T" transpose-chars
"C-U" unix-line-discard
"C-V" quoted-insert
"C-W" unix-word-rubout
"C-Y" yank
"C-]" character-search
"C-_" undo
" " to "/" self-insert
"0" to "9" self-insert
":" to "~" self-insert
"C-?" backward-delete-char
Emacs Meta bindings
"M-C-G" abort
"M-C-H" backward-kill-word
"M-C-I" tab-insert
"M-C-J" vi-editing-mode
"M-C-L" clear-display
"M-C-M" vi-editing-mode
"M-C-R" revert-line
"M-C-Y" yank-nth-arg
"M-C-[" complete
"M-C-]" character-search-backward
"M-space" set-mark
"M-#" insert-comment
"M-&" tilde-expand
"M-*" insert-completions
"M--" digit-argument
"M-." yank-last-arg
"M-0" digit-argument
"M-1" digit-argument
"M-2" digit-argument
"M-3" digit-argument
"M-4" digit-argument
"M-5" digit-argument
"M-6" digit-argument
"M-7" digit-argument
"M-8" digit-argument
"M-9" digit-argument
"M-<" beginning-of-history
"M-=" possible-completions
"M->" end-of-history
"M-?" possible-completions
"M-B" backward-word
"M-C" capitalize-word
"M-D" kill-word
"M-F" forward-word
"M-L" downcase-word
"M-N" non-incremental-forward-search-history
"M-P" non-incremental-reverse-search-history
"M-R" revert-line
"M-T" transpose-words
"M-U" upcase-word
"M-X" execute-named-command
"M-Y" yank-pop
"M-\" delete-horizontal-space
"M-~" tilde-expand
"M-C-?" backward-kill-word
"M-_" yank-last-arg
Emacs Control-X bindings
"C-XC-G" abort
"C-XC-R" re-read-init-file
"C-XC-U" undo
"C-XC-X" exchange-point-and-mark
"C-X(" start-kbd-macro
"C-X)" end-kbd-macro
"C-XE" call-last-kbd-macro
"C-XC-?" backward-kill-line
VI Insert Mode functions
"C-D" vi-eof-maybe
"C-H" backward-delete-char
"C-I" complete
"C-J" accept-line
"C-M" accept-line
"C-N" menu-complete
"C-P" menu-complete-backward
"C-R" reverse-search-history
"C-S" forward-search-history
"C-T" transpose-chars
"C-U" unix-line-discard
"C-V" quoted-insert
"C-W" vi-unix-word-rubout
"C-Y" yank
"C-[" vi-movement-mode
"C-_" vi-undo
" " to "~" self-insert
"C-?" backward-delete-char
VI Command Mode functions
"C-D" vi-eof-maybe
"C-E" emacs-editing-mode
"C-G" abort
"C-H" backward-char
"C-J" accept-line
"C-K" kill-line
"C-L" clear-screen
"C-M" accept-line
"C-N" next-history
"C-P" previous-history
"C-Q" quoted-insert
"C-R" reverse-search-history
"C-S" forward-search-history
"C-T" transpose-chars
"C-U" unix-line-discard
"C-V" quoted-insert
"C-W" vi-unix-word-rubout
"C-Y" yank
"C-_" vi-undo
" " forward-char
"#" insert-comment
"$" end-of-line
"%" vi-match
"&" vi-tilde-expand
"*" vi-complete
"+" next-history
"," vi-char-search
"-" previous-history
"." vi-redo
"/" vi-search
"0" beginning-of-line
"1" to "9" vi-arg-digit
";" vi-char-search
"=" vi-complete
"?" vi-search
"A" vi-append-eol
"B" vi-prev-word
"C" vi-change-to
"D" vi-delete-to
"E" vi-end-word
"F" vi-char-search
"G" vi-fetch-history
"I" vi-insert-beg
"N" vi-search-again
"P" vi-put
"R" vi-replace
"S" vi-subst
"T" vi-char-search
"U" revert-line
"W" vi-next-word
"X" vi-rubout
"Y" vi-yank-to
"\" vi-complete
"^" vi-first-print
"_" vi-yank-arg
"`" vi-goto-mark
"a" vi-append-mode
"b" vi-prev-word
"c" vi-change-to
"d" vi-delete-to
"e" vi-end-word
"f" vi-char-search
"h" backward-char
"i" vi-insertion-mode
"j" next-history
"k" previous-history
"l" forward-char
"m" vi-set-mark
"n" vi-search-again
"p" vi-put
"r" vi-change-char
"s" vi-subst
"t" vi-char-search
"u" vi-undo
"w" vi-next-word
"x" vi-delete
"y" vi-yank-to
"|" vi-column
"~" vi-change-case
- ~/.inputrc
- Individual readline initialization file
Brian Fox, Free Software Foundation
bfox@gnu.org
Chet Ramey, Case Western Reserve University
chet.ramey@case.edu
If you find a bug in readline, you should report it. But
first, you should make sure that it really is a bug, and that it appears in
the latest version of the readline library that you have.
Once you have determined that a bug actually exists, mail a bug
report to bug-readline@gnu.org. If you have a fix, you are
welcome to mail that as well! Suggestions and “philosophical”
bug reports may be mailed to bug-readline@gnu.org or posted to
the Usenet newsgroup gnu.bash.bug.
Comments and bug reports concerning this manual page should be
directed to chet.ramey@case.edu.
It's too big and too slow.
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