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READLINE(3) 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 /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.
Key Bindings
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.
Variables
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
set variable-name value
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.
comment-begin (“#”)
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.
menu-complete-display-prefix (Off)
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.
Conditional 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 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 /etc/inputrc:
$include /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.
Commands for Moving
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.
Commands for Manipulating the History
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.
Commands for Changing Text
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.
Killing and Yanking
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.
Numeric Arguments
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.
Completing
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.
menu-complete
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.
menu-complete-backward
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.
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
macro and store the definition.
call-last-kbd-macro (C-x e)
Re-execute the last keyboard macro defined, by making the
characters in the macro appear as if typed at the keyboard.
print-last-kbd-macro ()
Print the last keyboard macro defined in a format suitable
for the inputrc file.
Miscellaneous
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 [.
insert-comment (M-#)
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 Mode
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 Mode bindings
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
The Gnu Readline Library, Brian Fox and Chet Ramey
The Gnu History Library, Brian Fox and Chet Ramey
bash(1)
~/.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.
This page is part of the readline (GNU Readline library) project.
Information about the project can be found at
⟨http://www.gnu.org/software/readline/⟩. If you have a bug report
for this manual page, see
⟨http://cnswww.cns.cwru.edu/php/chet/readline/rltop.html#Bugs⟩.
This page was obtained from the project's upstream Git repository
⟨git://git.savannah.gnu.org/readline.git⟩ on 2025-08-11. (At that
time, the date of the most recent commit that was found in the
repository was 2025-07-11.) If you discover any rendering
problems in this HTML version of the page, or you believe there is
a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
GNU Readline 8.3 2024 December 30 READLINE(3)
Pages that refer to this page: bash(1), dbpmda(1), curs_termcap(3x), history(3), crash(8), lvm(8)
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