получить строку от пользователя с редактированием (get a line from a user with editing)
INITIALIZATION FILE
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, the ultimate default is /etc/inputrc. When a
program which uses the readline library starts up, the init file
is read, and the key bindings and variables are set. There are
only a few basic constructs allowed in the readline init file.
Blank lines are ignored. Lines beginning with a # are comments.
Lines beginning with a $ indicate conditional constructs. Other
lines denote key bindings and variable settings. Each program
using this library may add its 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.
The following symbolic character names are recognized while
processing key bindings: DEL, ESC, ESCAPE, LFD, NEWLINE, RET,
RETURN, RUBOUT, 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).
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 name may be specified in one of two ways: as a symbolic key
name, possibly with Meta- or Control- prefixes, or as a key
sequence. The name and key sequence 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 the symbolic character names are not
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- control prefix
\M- 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 should
be used to indicate a macro definition. Unquoted text is assumed
to be a function name. In the macro body, the backslash escapes
described above are expanded. Backslash will quote any other
character in the macro text, including " and '.
Bash allows the current readline key bindings to be displayed or
modified with the bind builtin command. The editing mode may be
switched during interactive use by using the -o option to the set
builtin command. Other programs using this library provide
similar mechanisms. The inputrc file may be edited and re-read
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 a variable value is read, 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:
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 (the default), readline attempts to bind the
control characters treated specially by the kernel's
terminal driver to their readline equivalents.
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.
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 is inserted in vi mode when the
insert-comment command is executed. 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 will cause 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 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,
common prefixes longer than this value are replaced with
an ellipsis when displaying possible completions.
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 will ask whether or
not the user wishes to view them; otherwise they are
simply listed on the terminal. A negative value causes
readline to never ask.
convert-meta (On)
If set to On, readline will convert characters with the
eighth bit set to an ASCII key sequence by stripping the
eighth bit and prefixing it with an escape character (in
effect, using escape as the meta prefix). The default is
On, but readline will set it to Off if the locale contains
eight-bit characters.
disable-completion (Off)
If set to On, readline will inhibit word completion.
Completion characters will be 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 begins with 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. Use the \1 and \2 escapes to
begin and end sequences of non-printing characters, which
can be used to embed a terminal control sequence into the
mode string.
enable-bracketed-paste (On)
When set to On, readline will configure the terminal in a
way that will enable it 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 can prevent pasted characters from being
interpreted as editing commands.
enable-keypad (Off)
When set to On, readline will try 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 will try to enable any meta
modifier key the terminal claims to support when it is
called. On many terminals, the meta key is used to send
eight-bit characters.
expand-tilde (Off)
If set to On, tilde expansion is performed when readline
attempts word completion.
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. If an attempt is made to set history-size
to a non-numeric value, the maximum number of history
entries will be set to 500.
horizontal-scroll-mode (Off)
When set 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 will enable eight-bit input (that
is, it will not clear the eighth bit in the characters it
reads), regardless of what the terminal claims it can
support. The name meta-flag is a synonym for this
variable. The default is Off, but readline will set it to
On if the locale contains eight-bit characters.
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 will terminate
an incremental search.
keymap (emacs)
Set the current readline keymap. The set of legal keymap
names is emacs, emacs-standard, emacs-meta, emacs-ctlx,
vi, vi-move, 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 no input is received within the timeout,
readline will use 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 will
wait 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, history lines that have been modified are
displayed 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, causes readline to match
files whose names begin with a `.' (hidden files) when
performing filename completion. If set to Off, the
leading `.' must be supplied by the user 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 will display characters with the
eighth bit set directly rather than as a meta-prefixed
escape sequence. The default is Off, but readline will
set it to On if the locale contains eight-bit characters.
page-completions (On)
If set to On, readline uses an internal more-like pager to
display a screenful of possible completions at a time.
print-completions-horizontally (Off)
If set to On, readline will display 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 accept-line is executed. By
default, history lines may be modified and retain
individual undo lists across calls to readline.
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. Use the \1 and
\2 escapes to 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. Use the \1 and
\2 escapes to 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 used.
$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 the full name of the terminal and the
portion of the terminal name before the first -.
This allows sun to match both sun and sun-cmd, 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 is assumed to be 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. Both string and boolean variables
may be tested. Boolean variables must be tested
against the values on and off.
$endif This command, as seen in the previous example, terminates
an $if command.
$else Commands in this branch of the $if directive are executed
if the test fails.
$include
This directive takes a single filename as an argument and
reads commands and bindings from that file. For example,
the following directive would read /etc/inputrc:
$include /etc/inputrc
