bash/lib/readline/doc/readline.3

.\"
.\" MAN PAGE COMMENTS to
.\"
.\"	Chet Ramey
.\"	Information Network Services
.\"	Case Western Reserve University
.\"	chet.ramey@case.edu
.\"
.\"	Last Change: Tue Jul 15 10:19:29 EDT 2025
.\"
.TH READLINE 3 "2024 July 15" "GNU Readline 8.3"
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.SH NAME
readline \- get a line from a user with editing
.SH SYNOPSIS
.LP
.nf
.ft B
#include <stdio.h>
#include <readline/readline.h>
#include <readline/history.h>
.ft
.fi
.LP
.nf
\fIchar *\fP
.br
\fBreadline\fP (\fIconst char *prompt\fP);
.fi
.SH COPYRIGHT
.if n Readline is Copyright (C) 1989\-2025 Free Software Foundation,  Inc.
.if t Readline is Copyright \(co 1989\-2025 Free Software Foundation, Inc.
.SH DESCRIPTION
.LP
.B readline
reads a line from the terminal
and return it, using
.B prompt
as a prompt.
If
.B prompt
is \fBNULL\fP or the empty string, \fBreadline\fP does not issue a prompt.
The line returned is allocated with
.IR 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 \fBreadline\fP editing function they might normally have,
this line may include embedded newlines and other special characters.
.LP
.B 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.
.LP
This manual page describes only the most basic use of \fBreadline\fP.
Much more functionality is available; see
\fIThe GNU Readline Library\fP and \fIThe GNU History Library\fP
for additional information.
.SH RETURN VALUE
.LP
.B readline
returns the text of the line read.
A blank line returns the empty string.
If
.B EOF
is encountered while reading a line, and the line is empty,
.B readline
returns
.BR NULL .
If an
.B EOF
is read with a non\-empty line, it is treated as a newline.
.SH NOTATION
.LP
This section uses Emacs-style editing concepts and uses its
notation for keystrokes.
Control keys are denoted by C\-\fIkey\fP, e.g., C\-n means Control\-N.
Similarly,
.I meta
keys are denoted by M\-\fIkey\fP, so M\-x means Meta\-X.
The Meta key is often labeled
.Q Alt
or
.Q Option .
.PP
On keyboards without a
.I Meta
key, M\-\fIx\fP means ESC \fIx\fP, i.e., press and release
the Escape key, then press and release the
.I x
key, in sequence.
This makes ESC the \fImeta prefix\fP.
The combination M\-C\-\fIx\fP means ESC Control\-\fIx\fP:
press and release the Escape key,
then press and hold the Control key while pressing the
.I x
key, then release both.
.PP
On some keyboards, the Meta key modifier produces characters with
the eighth bit (0200) set.
You can use the \fBenable\-meta\-key\fP 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.
.PP
If your \fIMeta\fP key produces a key sequence with the ESC meta prefix,
you can make M-\fIkey\fP key bindings you specify (see
.B "Readline Key Bindings"
below) do the same thing by setting the \fBforce\-meta\-prefix\fP variable.
.PP
.B Readline
commands may be given numeric
.IR 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., \fBkill\-line\fP)
makes that command act in a backward direction.
Commands whose behavior with arguments deviates from this are noted
below.
.PP
The \fIpoint\fP is the current cursor position, and \fImark\fP refers
to a saved cursor position.
The text between the point and mark is referred to as the \fIregion\fP.
.PP
When a command is described as \fIkilling\fP text, the text
deleted is saved for possible future retrieval
(\fIyanking\fP).
The killed text is saved in a \fIkill ring\fP.
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.
.SH INITIALIZATION FILE
.LP
.B Readline
is customized by putting commands in an initialization
file (the \fIinputrc\fP file).
The name of this file is taken from the value of the
.B INPUTRC
environment variable.
If that variable is unset, the default is
.IR \*~/.inputrc .
If that file  does not exist or cannot be read, \fBreadline\fP looks for
.IR /etc/inputrc .
When a program that uses the \fBreadline\fP library starts up,
\fBreadline\fP reads the initialization file
and sets the key bindings and variables found there,
before reading any user input.
.PP
There are only a few basic constructs allowed in the inputrc file.
Blank lines are ignored.
Lines beginning with a \fB#\fP are comments.
Lines beginning with a \fB$\fP indicate conditional constructs.
Other lines denote key bindings and variable settings.
.PP
The default key-bindings in this document
may be changed using key binding commands in the
.I inputrc
file.
Programs that use this library
may add their own commands and bindings.
.PP
For example, placing
.RS
.PP
M\-Control\-u: universal\-argument
.RE
or
.RS
C\-Meta\-u: universal\-argument
.RE
.LP
into the
.I inputrc
would make M\-C\-u execute the \fBreadline\fP command
.IR universal\-argument .
.PP
Key bindings may contain the following symbolic character names:
.IR DEL ,
.IR ESC ,
.IR ESCAPE ,
.IR LFD ,
.IR NEWLINE ,
.IR RET ,
.IR RETURN ,
.I RUBOUT
(a destructive backspace),
.IR SPACE ,
.IR SPC ,
and
.IR TAB .
.PP
In addition to command names, \fBreadline\fP allows keys to be bound
to a string that is inserted when the key is pressed (a \fImacro\fP).
The difference between a macro and a command is that a macro is
enclosed in single or double quotes.
.SS Key Bindings
The syntax for controlling key bindings in the
.I 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 \fIMeta\-\fP or \fIControl\-\fP 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.
.PP
When using the form \fBkeyname\fP:\^\fIfunction\-name\fP or \fImacro\fP,
.I keyname
is the name of a key spelled out in English.  For example:
.PP
.RS
.EX
.nf
Control-u: universal\-argument
Meta-Rubout: backward\-kill\-word
Control-o: \*"> output\*"
.fi
.EE
.RE
.LP
In the above example,
.I C\-u
is bound to the function
.BR universal\-argument ,
.I M\-DEL
is bound to the function
.BR backward\-kill\-word ,
and
.I C\-o
is bound to run the macro
expressed on the right hand side (that is, to insert the text
.Q "> output"
into the line).
.PP
In the second form,
\fB\*"keyseq\*"\fP:\^\fIfunction\-name\fP or \fImacro\fP,
.B keyseq
differs from
.B 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.
.PP
.RS
.EX
.nf
\*"\eC\-u\*": universal\-argument
\*"\eC\-x\eC\-r\*": re\-read\-init\-file
\*"\ee[11\*~\*": \*"Function Key 1\*"
.fi
.EE
.RE
.PP
In this example,
.I C\-u
is again bound to the function
.BR universal\-argument .
.I "C\-x C\-r"
is bound to the function
.BR re\-read\-init\-file ,
and
.I "ESC [ 1 1 \*~"
is bound to insert the text
.Q "Function Key 1" .
.PP
The full set of GNU Emacs style escape sequences available when specifying
key sequences is
.RS
.PD 0
.TP
.B \eC\-
A control prefix.
.TP
.B \eM\-
Adding the meta prefix or converting the following character to a meta
character, as described below under \fBforce-meta-prefix\fP.
.TP
.B \ee
An escape character.
.TP
.B \e\e
Backslash.
.TP
.B \e\*"
Literal \*", a double quote.
.TP
.B \e\*'
Literal \*', a single quote.
.RE
.PD
.PP
In addition to the GNU Emacs style escape sequences, a second
set of backslash escapes is available:
.RS
.PD 0
.TP
.B \ea
alert (bell)
.TP
.B \eb
backspace
.TP
.B \ed
delete
.TP
.B \ef
form feed
.TP
.B \en
newline
.TP
.B \er
carriage return
.TP
.B \et
horizontal tab
.TP
.B \ev
vertical tab
.TP
.B \e\fInnn\fP
The eight-bit character whose value is the octal value \fInnn\fP
(one to three digits).
.TP
.B \ex\fIHH\fP
The eight-bit character whose value is the hexadecimal value \fIHH\fP
(one or two hex digits).
.RE
.PD
.PP
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 \*'.
.PP
.B Bash
will display or modify the current \fBreadline\fP key bindings with the
.B bind
builtin command.
The
.B \-o emacs
or
.B \-o vi
options to the
.B set
builtin
change the editing mode during interactive use.
Other programs using this library provide similar mechanisms.
A user may always edit the
.I inputrc
file and have \fBreadline\fP re-read it if a program does not provide
any other means to incorporate new bindings.
.SS Variables
.B Readline
has variables that can be used to further customize its
behavior.
A variable may be set in the
.I inputrc
file with a statement of the form
.RS
.PP
\fBset\fP \fIvariable\-name\fP \fIvalue\fP
.RE
.PP
Except where noted, \fBreadline\fP variables can take the values
.B On
or
.B Off
(without regard to case).
Unrecognized variable names are ignored.
When \fBreadline\fP reads a variable value, empty or null values,
.Q "on"
(case-insensitive), and
.Q 1
are equivalent to \fBOn\fP.
All other values are equivalent to
\fBOff\fP.
.PP
The variables and their default values are:
.PP
.PD 0
.TP
.B 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
\fBenable\-active\-region\fP 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
.Q \ee[01;33m .
.TP
.B active\-region\-end\-color
A string variable that
.Q undoes
the effects of \fBactive\-region\-start\-color\fP
and restores
.Q 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
.Q \ee[0m .
.TP
.B bell\-style (audible)
Controls what happens when \fBreadline\fP wants to ring the terminal bell.
If set to \fBnone\fP, \fBreadline\fP never rings the bell.
If set to \fBvisible\fP, \fBreadline\fP uses a visible bell if one is available.
If set to \fBaudible\fP, \fBreadline\fP attempts to ring the terminal's bell.
.TP
.B bind\-tty\-special\-chars (On)
If set to \fBOn\fP, \fBreadline\fP attempts to bind
the control characters that are treated specially by the kernel's
terminal driver to their \fBreadline\fP equivalents.
These override the default \fBreadline\fP bindings described here.
Type
.Q "stty \-a"
at a \fBbash\fP prompt to see your current terminal settings,
including the special control characters (usually \fBcchars\fP).
This binding takes place on each call to \fBreadline\fP,
so changes made by
.Q stty
can take effect.
.TP
.B blink\-matching\-paren (Off)
If set to \fBOn\fP, \fBreadline\fP attempts to briefly move the cursor to an
opening parenthesis when a closing parenthesis is inserted.
.TP
.B colored\-completion\-prefix (Off)
If set to \fBOn\fP, when listing completions, \fBreadline\fP displays the
common prefix of the set of possible completions using a different color.
The color definitions are taken from the value of the \fBLS_COLORS\fP
environment variable.
If there is a color definition in \fB$LS_COLORS\fP for the custom suffix
.Q readline-colored-completion-prefix ,
\fBreadline\fP uses this color for
the common prefix instead of its default.
.TP
.B colored\-stats (Off)
If set to \fBOn\fP, \fBreadline\fP displays possible completions using different
colors to indicate their file type.
The color definitions are taken from the value of the \fBLS_COLORS\fP
environment variable.
.\" Tucking multiple macro calls into a paragraph tag requires some
.\" finesse.  We require `\c`, and while the single-font macros don't
.\" honor input trap continuation, the font alternation macros do.
.TP
.BR comment\-begin\ ( \c
.Q \fB#\fP \fB)\fP
The string that the \fBreadline\fP
.B insert\-comment
command inserts.
This command is bound to
.B M\-#
in emacs mode and to
.B #
in vi command mode.
.TP
.B 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.
.TP
.B completion\-ignore\-case (Off)
If set to \fBOn\fP, \fBreadline\fP performs filename matching and completion
in a case\-insensitive fashion.
.TP
.B completion\-map\-case (Off)
If set to \fBOn\fP, and \fBcompletion\-ignore\-case\fP is enabled,
\fBreadline\fP
treats hyphens (\fI\-\fP) and underscores (\fI_\fP) as equivalent when
performing case\-insensitive filename matching and completion.
.TP
.B 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, \fBreadline\fP
replaces common prefixes longer than this value
with an ellipsis when displaying possible completions.
If a completion begins with a period,
and \fBeadline\fP is completing filenames,
it uses three underscores instead of an ellipsis.
.TP
.B completion\-query\-items (100)
This determines when the user is queried about viewing
the number of possible completions
generated by the \fBpossible\-completions\fP 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,
\fBreadline\fP asks whether or not the user wishes to view them;
otherwise \fBreadline\fP simply lists them on the terminal.
A zero value means \fBreadline\fP should never ask; negative values are
treated as zero.
.TP
.B convert\-meta (On)
If set to \fBOn\fP, \fBreadline\fP 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 \fIOn\fP, but \fBreadline\fP sets it to \fIOff\fP
if the locale contains
characters whose encodings may include bytes with the eighth bit set.
This variable is dependent on the \fBLC_CTYPE\fP locale category, and
may change if the locale changes.
This variable also affects key bindings; see the description of
\fBforce\-meta\-prefix\fP below.
.TP
.B disable\-completion (Off)
If set to \fBOn\fP, \fBreadline\fP inhibits word completion.
Completion characters are inserted into the line as if they
had been mapped to \fBself-insert\fP.
.TP
.B echo\-control\-characters (On)
When set to \fBOn\fP, on operating systems that indicate they support it,
\fBreadline\fP echoes a character corresponding to a signal generated from the
keyboard.
.TP
.B editing\-mode (emacs)
Controls whether \fBreadline\fP uses a set of key bindings similar
to \fIEmacs\fP or \fIvi\fP.
.B editing\-mode
can be set to either
.B emacs
or
.BR vi .
.TP
.B emacs\-mode\-string (@)
If the \fIshow\-mode\-in\-prompt\fP 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 \e1 and \e2 escapes begin and end sequences of
non-printing characters, which can be used to embed a terminal control
sequence into the mode string.
.TP
.B enable\-active\-region (On)
When this variable is set to \fIOn\fP, \fBreadline\fP allows certain commands
to designate the region as \fIactive\fP.
When the region is active, \fBreadline\fP
highlights the text in the region using the value of the
.B 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.
.TP
.B enable\-bracketed\-paste (On)
When set to \fBOn\fP, \fBreadline\fP 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 \fIbracketed\-paste mode\fP;
it prevents \fBreadline\fP from executing any editing commands bound to key
sequences appearing in the pasted text.
.TP
.B enable\-keypad (Off)
When set to \fBOn\fP, \fBreadline\fP tries to enable the application
keypad when it is called.
Some systems need this to enable the arrow keys.
.TP
.B enable\-meta\-key (On)
When set to \fBOn\fP, \fBreadline\fP 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).
.TP
.B expand\-tilde (Off)
If set to \fBOn\fP, \fBreadline\fP performs tilde expansion when it
attempts word completion.
.TP
.B force\-meta\-prefix (Off)
If set to \fBOn\fP, \fBreadline\fP modifies its behavior when binding key
sequences containing \eM- or Meta-
(see \fBKey Bindings\fP above) by converting a key sequence of the form
\eM\-\fIC\fP or Meta\-\fIC\fP to the two-character sequence
\fBESC\fP \fIC\fP (adding the meta prefix).
If
.B force\-meta\-prefix
is set to \fBOff\fP (the default),
\fBreadline\fP uses the value of the
.B convert\-meta
variable to determine whether to perform this conversion:
if \fBconvert\-meta\fP is \fBOn\fP,
\fBreadline\fP performs the conversion described above;
if it is \fBOff\fP, \fBreadline\fP converts \fIC\fP to a meta character by
setting the eighth bit (0200).
.TP
.B history\-preserve\-point (Off)
If set to \fBOn\fP, the history code attempts to place point at the
same location on each history line retrieved with \fBprevious-history\fP
or \fBnext-history\fP.
.TP
.B 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 \fIhistory\-size\fP to a non-numeric value will set
the maximum number of history entries to 500.
.TP
.B horizontal\-scroll\-mode (Off)
Setting this variable to \fBOn\fP makes \fBreadline\fP 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.
.TP
.B input\-meta (Off)
If set to \fBOn\fP, \fBreadline\fP 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 \fIOff\fP, but \fBreadline\fP sets it to \fIOn\fP
if the locale contains characters whose encodings may include bytes
with the eighth bit set.
This variable is dependent on the \fBLC_CTYPE\fP locale category, and
its value may change if the locale changes.
The name \fBmeta\-flag\fP is a synonym for \fBinput\-meta\fP.
.TP
.BR isearch\-terminators\ ( \c
.Q \fBC\-[C\-j\fP \fB)\fP
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
\fIESC\fP and \fBC\-j\fP terminate an incremental search.
.TP
.B keymap (emacs)
Set the current \fBreadline\fP keymap.
The set of valid keymap names is
\fIemacs, emacs\-standard, emacs\-meta, emacs\-ctlx, vi,
vi\-command\fP, and
.IR vi\-insert .
\fIvi\fP is equivalent to \fIvi\-command\fP;
\fIemacs\fP is equivalent to \fIemacs\-standard\fP.
The default value is \fIemacs\fP;
the value of
.B editing\-mode
also affects the default keymap.
.TP
.B keyseq\-timeout (500)
Specifies the duration \fBreadline\fP 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 \fBreadline\fP 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
\fBreadline\fP 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, \fBreadline\fP waits until another key is pressed to
decide which key sequence to complete.
.TP
.B mark\-directories (On)
If set to \fBOn\fP, completed directory names have a slash appended.
.TP
.B mark\-modified\-lines (Off)
If set to \fBOn\fP, \fBreadline\fP displays history lines
that have been modified
with a preceding asterisk (\fB*\fP).
.TP
.B mark\-symlinked\-directories (Off)
If set to \fBOn\fP, completed names which are symbolic links to directories
have a slash appended, subject to the value of \fBmark\-directories\fP.
.TP
.B match\-hidden\-files (On)
This variable, when set to \fBOn\fP, forces \fBreadline\fP to match files whose
names begin with a
.Q .
(hidden files) when performing filename completion.
If set to \fBOff\fP, the user must include the leading
.Q . 
in the filename to be completed.
.TP
.B menu\-complete\-display\-prefix (Off)
If set to \fBOn\fP, menu completion displays the common prefix of the
list of possible completions (which may be empty) before cycling through
the list.
.TP
.B output\-meta (Off)
If set to \fBOn\fP, \fBreadline\fP displays characters with the
eighth bit set directly rather than as a meta-prefixed escape
sequence.
The default is \fIOff\fP, but \fBreadline\fP sets it to \fIOn\fP
if the locale contains characters whose encodings may include
bytes with the eighth bit set.
This variable is dependent on the \fBLC_CTYPE\fP locale category, and
its value may change if the locale changes.
.TP
.B page\-completions (On)
If set to \fBOn\fP, \fBreadline\fP uses an internal pager resembling
.IR more (1)
to display a screenful of possible completions at a time.
.TP
.B prefer\-visible\-bell
See \fBbell\-style\fP.
.TP
.B print\-completions\-horizontally (Off)
If set to \fBOn\fP, \fBreadline\fP displays completions with matches
sorted horizontally in alphabetical order, rather than down the screen.
.TP
.B revert\-all\-at\-newline (Off)
If set to \fBOn\fP, \fBreadline\fP will undo all changes to history lines
before returning when executing \fBaccept\-line\fP.
By default,
history lines may be modified and retain individual undo lists across
calls to \fBreadline()\fP.
.TP
.B search\-ignore\-case (Off)
If set to \fBOn\fP, \fBreadline\fP performs incremental and non-incremental
history list searches in a case\-insensitive fashion.
.TP
.B show\-all\-if\-ambiguous (Off)
This alters the default behavior of the completion functions.
If set to
.BR On ,
words which have more than one possible completion cause the
matches to be listed immediately instead of ringing the bell.
.TP
.B show\-all\-if\-unmodified (Off)
This alters the default behavior of the completion functions in
a fashion similar to \fBshow\-all\-if\-ambiguous\fP.
If set to
.BR 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.
.TP
.B show\-mode\-in\-prompt (Off)
If set to \fBOn\fP, 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., \fIemacs\-mode\-string\fP).
.TP
.B skip\-completed\-text (Off)
If set to \fBOn\fP, 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, \fBreadline\fP 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.
.TP
.B vi\-cmd\-mode\-string ((cmd))
If the \fIshow\-mode\-in\-prompt\fP 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 \e1 and \e2 escapes begin and end sequences of
non-printing characters, which can be used to embed a terminal control
sequence into the mode string.
.TP
.B vi\-ins\-mode\-string ((ins))
If the \fIshow\-mode\-in\-prompt\fP 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 \e1 and \e2 escapes begin and end sequences of
non-printing characters, which can be used to embed a terminal control
sequence into the mode string.
.TP
.B visible\-stats (Off)
If set to \fBOn\fP, a character denoting a file's type as reported
by \fIstat\fP(2) is appended to the filename when listing possible
completions.
.PD
.SS Conditional Constructs
.B 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.
.TP
.B $if
The
.B $if
construct allows bindings to be made based on the
editing mode, the terminal being used, or the application using
\fBreadline\fP.
The text of the test, after any comparison operator,
extends to the end of the line;
unless otherwise noted, no characters are required to isolate it.
.RS
.TP
.B mode
The \fBmode=\fP form of the \fB$if\fP directive is used to test
whether \fBreadline\fP is in emacs or vi mode.
This may be used in conjunction
with the \fBset keymap\fP command, for instance, to set bindings in
the \fIemacs\-standard\fP and \fIemacs\-ctlx\fP keymaps only if
\fBreadline\fP is starting out in emacs mode.
.TP
.B term
The \fBterm=\fP 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
.B =
is tested against both the full name of the terminal and the portion
of the terminal name before the first \fB\-\fP.
This allows
.I xterm
to match both
.I xterm
and
.IR xterm\-256color ,
for instance.
.TP
.B version
The \fBversion\fP test may be used to perform comparisons against
specific \fBreadline\fP versions.
The \fBversion\fP expands to the current \fBreadline\fP version.
The set of comparison operators includes
.BR = ,
(and
.BR == ),
.BR != ,
.BR <= ,
.BR >= ,
.BR < ,
and
.BR > .
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., \fB7.1\fP).
If the minor version is omitted, it
defaults to \fB0\fP.
The operator may be separated from the string \fBversion\fP
and from the version number argument by whitespace.
.TP
.I application
The \fIapplication\fP construct is used to include
application-specific settings.
Each program using the \fBreadline\fP
library sets the \fIapplication name\fP, 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 \fBbash\fP:
.PP
.RS
.EX
.nf
\fB$if\fP Bash
# Quote the current or previous word
\*"\eC-xq\*": \*"\eeb\e\*"\eef\e\*"\*"
\fB$endif\fP
.fi
.EE
.RE
.TP
.I variable
The \fIvariable\fP construct provides simple equality tests for \fBreadline\fP
variables and values.
The permitted comparison operators are \fI=\fP, \fI==\fP, and \fI!=\fP.
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 \fIon\fP and \fIoff\fP.
.RE
.TP
.B $else
Commands in this branch of the \fB$if\fP directive are executed if
the test fails.
.TP
.B $endif
This command, as seen in the previous example, terminates an
\fB$if\fP command.
.TP
.B $include
This directive takes a single filename as an argument and reads commands
and key bindings from that file.
For example, the following directive would read \fI/etc/inputrc\fP:
.PP
.RS
.nf
\fB$include\fP \^ \fI/etc/inputrc\fP
.fi
.RE
.SH SEARCHING
.B Readline
provides commands for searching through the command history
for lines containing a specified string.
There are two search modes:
.I incremental
and
.IR non-incremental .
.PP
Incremental searches begin before the user has finished typing the
search string.
As each character of the search string is typed, \fBreadline\fP 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 \fBC\-r\fP to
search backward in the history for a particular string.
Typing \fBC\-s\fP searches forward through the history.
The characters present in the value of the \fBisearch-terminators\fP
variable are used to terminate an incremental search.
If that variable has not been assigned a value,
\fIESC\fP and \fBC\-j\fP terminate an incremental search.
\fBC\-g\fP 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.
.PP
To find other matching entries in the history list, type \fBC\-r\fP or
\fBC\-s\fP 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 \fBreadline\fP 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.
.PP
.B Readline
remembers the last incremental search string.
If two \fBC\-r\fPs are typed without any intervening characters defining
a new search string, \fBreadline\fP uses any remembered search string.
.PP
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.
.SH EDITING COMMANDS
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.
.PP
In the following descriptions, \fIpoint\fP refers to the current cursor
position, and \fImark\fP refers to a cursor position saved by the
\fBset\-mark\fP command.
The text between the point and mark is referred to as the \fIregion\fP.
.B Readline
has the concept of an \fIactive region\fP:
when the region is active, \fBreadline\fP redisplay
highlights the region using the value of the
.B active\-region\-start\-color
variable.
The \fBenable\-active\-region\fP variable turns this on and off.
Several commands set the region to active; those are noted below.
.SS Commands for Moving
.PD 0
.TP
.B 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.
.TP
.B end\-of\-line (C\-e)
Move to the end of the line.
This may also be bound to the End key on some keyboards.
.TP
.B forward\-char (C\-f)
Move forward a character.
This may also be bound to the right arrow key on some keyboards.
.TP
.B backward\-char (C\-b)
Move back a character.
.TP
.B forward\-word (M\-f)
Move forward to the end of the next word.
Words are composed of alphanumeric characters (letters and digits).
.TP
.B backward\-word (M\-b)
Move back to the start of the current or previous word.
Words are composed of alphanumeric characters (letters and digits).
.TP
.B 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
\fBreadline\fP 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.
.TP
.B 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
\fBreadline\fP line does not take up more than one physical line or if
the length of the current \fBreadline\fP line is
not greater than the length of the prompt
plus the screen width.
.TP
.B 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.
.TP
.B 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.
.TP
.B redraw\-current\-line
Refresh the current line.
.PD
.SS Commands for Manipulating the History
.PD 0
.TP
.B 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
\fBadd_history()\fP.
If the line is a modified history line,
restore the history line to its original state.
.TP
.B 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.
.TP
.B 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.
.TP
.B beginning\-of\-history (M\-<)
Move to the first line in the history.
.TP
.B end\-of\-history (M\->)
Move to the end of the input history, i.e., the line currently being
entered.
.TP
.B 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.
.TP
.B
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.
.TP
.B reverse\-search\-history (C\-r)
Search backward starting at the current line and moving
.Q up
through the history as necessary.
This is an incremental search.
This command sets the region to the matched text and activates the region.
.TP
.B forward\-search\-history (C\-s)
Search forward starting at the current line and moving
.Q down
through the history as necessary.
This is an incremental search.
This command sets the region to the matched text and activates the region.
.TP
.B 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.
.TP
.B 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.
.TP
.B 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.
.TP
.B 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.
.TP
.B 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.
.TP
.B 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.
.TP
.B 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
.IR n ,
insert the \fIn\fPth word from the previous command (the words
in the previous command begin with word 0).
A negative argument inserts the \fIn\fPth word from the end of
the previous command.
Once the argument \fIn\fP is computed,
this uses the history expansion facilities to extract the
\fIn\fPth word, as if the
.Q !\fIn\fP
history expansion had been specified.
.TP
.B
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 \fByank\-nth\-arg\fP.
Successive calls to \fByank\-last\-arg\fP 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
.Q !$
history expansion had been specified.
.PD
.SS Commands for Changing Text
.PD 0
.TP
.B \fIend\-of\-file\fP (usually C\-d)
The character indicating end-of-file as set, for example, by
.IR stty (1).
If this character is read when there are no characters
on the line, and point is at the beginning of the line, \fBreadline\fP
interprets it as the end of input and returns
.SM
.BR EOF .
.TP
.B delete\-char (C\-d)
Delete the character at point.
If this function is bound to the
same character as the tty \fBEOF\fP character, as \fBC\-d\fP
commonly is, see above for the effects.
This may also be bound to the Delete key on some keyboards.
.TP
.B backward\-delete\-char (Rubout)
Delete the character behind the cursor.
When given a numeric argument,
save the deleted text on the kill ring.
.TP
.B 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.
.TP
.B quoted\-insert (C\-q, C\-v)
Add the next character typed to the line verbatim.
This is how to insert characters like \fBC\-q\fP, for example.
.TP
.B tab\-insert (M-TAB)
Insert a tab character.
.TP
.B "self\-insert (a, b, A, 1, !, \fR.\|.\|.\fP)"
Insert the character typed.
.TP
.B bracketed\-paste\-begin
This function is intended to be bound to the
.Q "bracketed paste"
escape
sequence sent by some terminals, and such a binding is assigned by default.
It allows \fBreadline\fP 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 \fBself\-insert\fP instead of
executing any editing commands.
.IP
Bracketed paste sets the region to the inserted text and activates the region.
.TP
.B 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.
.TP
.B 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.
.TP
.B upcase\-word (M\-u)
Uppercase the current (or following) word.
With a negative argument,
uppercase the previous word, but do not move point.
.TP
.B downcase\-word (M\-l)
Lowercase the current (or following) word.
With a negative argument,
lowercase the previous word, but do not move point.
.TP
.B capitalize\-word (M\-c)
Capitalize the current (or following) word.
With a negative argument,
capitalize the previous word, but do not move point.
.TP
.B 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 \fBemacs\fP mode;
\fBvi\fP mode does overwrite differently.
Each call to \fIreadline()\fP starts in insert mode.
.IP
In overwrite mode, characters bound to \fBself\-insert\fP replace
the text at point rather than pushing the text to the right.
Characters bound to \fBbackward\-delete\-char\fP 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.
.PD
.SS Killing and Yanking
.PD 0
.TP
.B 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.
.TP
.B 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.
.TP
.B unix\-line\-discard (C\-u)
Kill backward from point to the beginning of the line,
saving the killed text on the kill-ring.
.\" There is no real difference between this and backward-kill-line
.TP
.B kill\-whole\-line
Kill all characters on the current line, no matter where point is.
.TP
.B 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 \fBforward\-word\fP.
.TP
.B backward\-kill\-word (M\-Rubout)
Kill the word behind point.
Word boundaries are the same as those used by \fBbackward\-word\fP.
.TP
.B 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.
.TP
.B 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.
.TP
.B delete\-horizontal\-space (M\-\e)
Delete all spaces and tabs around point.
.TP
.B kill\-region
Kill the text in the current region.
.TP
.B copy\-region\-as\-kill
Copy the text in the region to the kill buffer,
so it can be yanked immediately.
.TP
.B copy\-backward\-word
Copy the word before point to the kill buffer.
The word boundaries are the same as \fBbackward\-word\fP.
.TP
.B copy\-forward\-word
Copy the word following point to the kill buffer.
The word boundaries are the same as \fBforward\-word\fP.
.TP
.B yank (C\-y)
Yank the top of the kill ring into the buffer at point.
.TP
.B yank\-pop (M\-y)
Rotate the kill ring, and yank the new top.
Only works following
.B yank
or
.BR yank\-pop .
.PD
.SS Numeric Arguments
.PD 0
.TP
.B digit\-argument (M\-0, M\-1, \fR.\|.\|.\fP, M\-\-)
Add this digit to the argument already accumulating, or start a new
argument.
M\-\- starts a negative argument.
.TP
.B 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
.B 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.
.PD
.SS Completing
.PD 0
.TP
.B complete (TAB)
Attempt to perform completion on the text before point.
The actual completion performed is application-specific.
.BR Bash ,
for instance, attempts programmable completion first,
otherwise treating the text as a
variable (if the text begins with \fB$\fP),
username (if the text begins with \fB\*~\fP),
hostname (if the text begins with \fB@\fP), or
command (including aliases, functions, and builtins) in turn.
If none of these produces a match, it falls back to filename completion.
.BR Gdb ,
on the other hand,
allows completion of program functions and variables, and
only attempts filename completion under certain circumstances.
The default \fBreadline\fP completion is filename completion.
.TP
.B possible\-completions (M\-?)
List the possible completions of the text before point.
When displaying completions, \fBreadline\fP sets the number of columns used
for display to the value of \fBcompletion-display-width\fP, the value of
the environment variable
.BR COLUMNS ,
or the screen width, in that order.
.TP
.B insert\-completions (M\-*)
Insert all completions of the text before point
that would have been generated by
\fBpossible\-completions\fP,
separated by a space.
.TP
.B menu\-complete
Similar to \fBcomplete\fP, but replaces the word to be completed
with a single match from the list of possible completions.
Repeatedly executing \fBmenu\-complete\fP steps through the list
of possible completions, inserting each match in turn.
At the end of the list of completions,
\fBmenu\-complete\fP rings the bell
(subject to the setting of \fBbell\-style\fP)
and restores the original text.
An argument of \fIn\fP moves \fIn\fP positions forward in the list
of matches; a negative argument moves backward through the list.
This command is intended to be bound to \fBTAB\fP, but is unbound
by default.
.TP
.B menu\-complete\-backward
Identical to \fBmenu\-complete\fP, but moves backward through the list
of possible completions, as if \fBmenu\-complete\fP had been given a
negative argument.
This command is unbound by default.
.TP
.B export\-completions
Perform completion on the word before point as described above
and write the list of possible completions to \fBreadline\fP's output
stream using the following format, writing information on separate lines:
.RS
.PD
.IP \(bu
.PD 0
the number of matches \fIN\fP;
.IP \(bu
the word being completed;
.IP \(bu
\fIS\fP:\fIE\fP,
where \fIS\fP and \fIE\fP are the start and end offsets of the word
in the \fBreadline\fP line buffer; then
.IP \(bu
each match, one per line
.RE
.PD
.IP
If there are no matches, the first line will be
.Q 0 ,
and this command does not print any output after the \fIS\fP:\fIE\fP.
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 \fIS\fP:\fIE\fP,
then the matches on subsequent lines.
In this case, \fIN\fP will include the first line with the common prefix.
.IP
The user or application
should be able to accommodate the possibility of a blank line.
The intent is that the user or application reads \fIN\fP lines after
the line containing \fIS\fP:\fIE\fP to obtain the match list.
This command is unbound by default.
.TP
.B delete\-char\-or\-list
Deletes the character under the cursor if not at the beginning or
end of the line (like \fBdelete\-char\fP).
At the end of the line, it behaves identically to \fBpossible\-completions\fP.
This command is unbound by default.
.PD
.SS "Keyboard Macros"
.PD 0
.TP
.B start\-kbd\-macro (C\-x (\^)
Begin saving the characters typed into the current keyboard macro.
.TP
.B end\-kbd\-macro (C\-x )\^)
Stop saving the characters typed into the current keyboard macro
and store the definition.
.TP
.B 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.
.TP
.B print\-last\-kbd\-macro ()
Print the last keyboard macro defined in a format suitable for the
\fIinputrc\fP file.
.PD
.SS Miscellaneous
.PD 0
.TP
.B re\-read\-init\-file (C\-x C\-r)
Read in the contents of the \fIinputrc\fP file, and incorporate
any bindings or variable assignments found there.
.TP
.B abort (C\-g)
Abort the current editing command and
ring the terminal's bell (subject to the setting of
.BR bell\-style ).
.TP
.B do\-lowercase\-version (M\-A, M\-B, M\-\fIx\fP, \fR.\|.\|.\fP)
If the metafied character \fIx\fP is uppercase, run the command
that is bound to the corresponding metafied lowercase character.
The behavior is undefined if \fIx\fP is already lowercase.
.TP
.B prefix\-meta (ESC)
Metafy the next character typed.
.SM
.B ESC
.B f
is equivalent to
.BR Meta\-f .
.TP
.B undo (C\-_, C\-x C\-u)
Incremental undo, separately remembered for each line.
.TP
.B revert\-line (M\-r)
Undo all changes made to this line.
This is like executing the
.B undo
command enough times to return the line to its initial state.
.TP
.B tilde\-expand (M\-~)
Perform tilde expansion on the current word.
.TP
.B set\-mark (C\-@, M\-<space>)
Set the mark to the point.
If a numeric argument is supplied, set the mark to that position.
.TP
.B 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.
.TP
.B character\-search (C\-])
Read a character and move point to the next occurrence of that character.
A negative argument searches for previous occurrences.
.TP
.B 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.
.TP
.B 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
.IR "ESC [" .
If this sequence is bound to
.Q \ee[ ,
keys producing CSI sequences have no effect
unless explicitly bound to a \fBreadline\fP command,
instead of inserting stray characters into the editing buffer.
This is unbound by default, but usually bound to
.IR "ESC [" .
.TP
.B insert\-comment (M\-#)
Without a numeric argument, insert the value of the \fBreadline\fP
.B 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 \fBcomment\-begin\fP, insert the value; otherwise delete
the characters in \fBcomment-begin\fP from the beginning of the line.
In either case, the line is accepted as if a newline had been typed.
The default value of
\fBcomment\-begin\fP 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.
.TP
.B dump\-functions
Print all of the functions and their key bindings
to the \fBreadline\fP output stream.
If a numeric argument is supplied,
the output is formatted in such a way that it can be made part
of an \fIinputrc\fP file.
.TP
.B dump\-variables
Print all of the settable variables and their values
to the \fBreadline\fP output stream.
If a numeric argument is supplied,
the output is formatted in such a way that it can be made part
of an \fIinputrc\fP file.
.TP
.B dump\-macros
Print all of the \fBreadline\fP key sequences bound to macros and the
strings they output
to the \fBreadline\fP output stream.
If a numeric argument is supplied,
the output is formatted in such a way that it can be made part
of an \fIinputrc\fP file.
.TP
.B execute\-named\-command (M-x)
Read a bindable \fBreadline\fP 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.
.TP
.B emacs\-editing\-mode (C\-e)
When in
.B vi
command mode, this switches \fBreadline\fP to
.B emacs
editing mode.
.TP
.B vi\-editing\-mode (M\-C\-j)
When in
.B emacs
editing mode, this switches to
.B vi
editing mode.
.PD
.SH DEFAULT KEY BINDINGS
.LP
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
.I metafied
characters.
The printable ASCII characters not mentioned in the list of emacs
standard bindings are bound to the
.B 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
.BR self\-insert .
Characters assigned to signal generation by
.IR 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 \fBreadline\fP
to ring the bell (subject to the setting of the
.B bell\-style
variable).
.SS Emacs Mode
.RS +.6i
.nf
.ta 2.5i
.sp
Emacs Standard bindings
.PP
"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
.PP
Emacs Meta bindings
.PP
"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-\e"  delete-horizontal-space
"M-\*~"  tilde-expand
"M-C-?"  backward-kill-word
"M-_"  yank-last-arg
.PP
Emacs Control-X bindings
.PP
"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
.RE
.SS VI Mode bindings
.RS +.6i
.nf
.ta 2.5i
.PP
VI Insert Mode functions
.PP
"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
.PP
VI Command Mode functions
.PP
"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
"\e"  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
.RE
.SH "SEE ALSO"
.PD 0
.TP
\fIThe Gnu Readline Library\fP, Brian Fox and Chet Ramey
.TP
\fIThe Gnu History Library\fP, Brian Fox and Chet Ramey
.TP
\fIbash\fP(1)
.PD
.SH FILES
.PD 0
.TP
.FN \*~/.inputrc
Individual \fBreadline\fP initialization file
.PD
.SH AUTHORS
Brian Fox, Free Software Foundation
.br
bfox@gnu.org
.PP
Chet Ramey, Case Western Reserve University
.br
chet.ramey@case.edu
.SH BUG REPORTS
If you find a bug in
.BR 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
.B readline
library that you have.
.PP
Once you have determined that a bug actually exists, mail a
bug report to \fIbug\-readline\fP@\fIgnu.org\fP.
If you have a fix, you are welcome to mail that
as well!  Suggestions and
.Q philosophical
bug reports may be mailed
to \fPbug-readline\fP@\fIgnu.org\fP or posted to the Usenet
newsgroup
.BR gnu.bash.bug .
.PP
Comments and bug reports concerning
this manual page should be directed to
.IR chet.ramey@case.edu .
.SH BUGS
It's too big and too slow.