#include <readline.h> #include <history.h>
typedef int Function (); char *readline (prompt) char *prompt;
int rl_add_defun (name, function, key) char *name; Function *function; int key;
int rl_bind_key (key, function) int key; Function *function;
int rl_unbind_key (key) int key;
int rl_bind_key_in_map (key, function, keymap) int key; Function *function; Keymap keymap;
int rl_unbind_key_in_map (key, keymap) int key; Keymap keymap;int rl_macro_bind (keyseq, macro, keymap) char *keyseq, *macro; Keymap keymap;
int rl_variable_bind (variable, value) char *variable, *value;
int rl_parse_and_bind (line) char *line;
int rl_translate_keyseq (keyseq, array, len) char *keyseq, *array; int *len;
Function *rl_named_function (command) char *command;
Function *rl_function_of_keyseq (keyseq, keymap, type) char *keyseq; Keymap keymap; int *type;
char **rl_invoking_keyseqs (function) Function *function;
char **rl_invoking_keyseqs_in_map (function, keymap) Function *function; Keymap keymap;
void rl_function_dumper (readable) int readable;
char **rl_funmap_names ()
readline will read a line from the terminal and return it, using prompt as a prompt. If prompt is null, no prompt is issued. The line returned is allocated with malloc(3), so the caller must free it when finished. The line returned has the final newline removed, so only the text of the line remains.
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.
In the following descriptions, keymap can be one of emacs_keymap, emacs_meta_keymap, emacs_ctlx_keymap, vi_insertion_keymap, or vi_movement_keymap.
rl_add_defun makes name appear as a bindable readline command, and makes function be the function called when that command is invoked. If key is not -1, it is bound to function in the current keymap.
rl_bind_key causes key to invoke function. The binding is made in the current keymap.
rl_unbind_key removes the binding for key in the current keymap.
rl_bind_key_in_map makes the key entry in keymap invoke function.
rl_unbind_key_in_map removes the binding for key in keymap keymap.
rl_macro_bind makes keyseq insert the string macro. The binding is performed in keymap.
rl_variable_bind sets the value of the readline variable variable to value.
rl_parse_and_bind takes as an argument a line of the same form as the readline startup file (see INITIALIZATION FILE below) and executes the commands therein.
rl_translate_keyseq converts keyseq into a new string, storing the result in array. This translates control and meta prefixes and the readline character escape sequences (see Key Bindings below). The length of the translated sequence is returned in *len.
rl_named_function returns the function that is executed when the readline command command is invoked.
rl_function_of_keyseq returns the function that is executed when keyseq is read and keymap is the current keymap. type is set to indicate whether the return value corresponds to a function, macro, or auxiliary keymap.
rl_invoking_keyseqs returns all of the key sequences in the current keymap that invoke function.
rl_invoking_keyseqs_in_map returns all of the key sequences in keymap that invoke function.
rl_function_dumper prints all of the readline functions and their bindings to the readline output stream. If readable is non-zero, the output is formattted so that it can be read back in to restore the bindings.
rl_funmap_names returns an array of all known readline bindable function names. The array is sorted.
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, NULL is returned. If an EOF is read with a non-empty line, it is treated as a newline.
Unless otherwise stated, the other functions return 0 on success and non-zero on failure.
An emacs-style notation is used to denote 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. (On keyboards without a meta key, M-x means ESC x, i.e., press the Escape key then the x key. This makes ESC the meta prefix. The combination M-C-x means ESC-Control-x, or press the Escape key then hold the Control key while pressing the x key.)
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) causes that command to act in a backward direction. Commands whose behavior with arguments deviates from this are noted.
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 cause the text to be accumulated 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 name of this file is taken from the value of the INPUTRC variable. If that variable is unset, the default is ~/.inputrc. When a program which uses the readline library starts up, the init file is read, and the key bindings 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
The following symbolic character names are recognized while processing key bindings: RUBOUT, DEL, ESC, LFD, NEWLINE, RET, RETURN, SPC, SPACE, 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 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. When using the form keyname:function-name or macro, keyname is the name of a key spelled out in English. For example:
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.
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 escape sequences is
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. Backslash will quote any 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.
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. The variables and their default values are:
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 three parser directives used.
$if bash # Quote the current or previous word "\C-xq": "\eb\"\ef\"" $endif
The following is a list of the names of the commands and the default key sequences to which they are bound.
The following is a list of the default emacs and vi bindings. Characters with the 8th bit set are written as M-<character>, and are referred to as metafied characters. The printable ASCII characters not mentioned in the list of emacs standard bindings are bound to the self-insert function, which just inserts the given character into the input line. In vi insertion mode, all characters not specifically mentioned are bound to self-insert. Characters assigned to signal generation by stty(1) or the terminal driver, such as C-Z or C-C, retain that function. Upper and lower case metafied characters are bound to the same function in the emacs mode meta keymap. The remaining characters are unbound, which causes readline to ring the bell (subject to the setting of the bell-style variable).
Emacs Standard bindings
"C-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-_" -> undo
" " to "/" -> self-insert
"0" to "9" -> self-insert
":" to "~" -> self-insert
"C-?" -> backward-delete-char
Emacs Meta bindings
"M-C-H" -> backward-kill-word
"M-C-I" -> tab-insert
"M-C-J" -> vi-editing-mode
"M-C-M" -> vi-editing-mode
"M-C-R" -> revert-line
"M-C-Y" -> yank-nth-arg
"M-C-[" -> complete
"M-&" -> tilde-expand
"M--" -> digit-argument
"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->" -> 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-O" -> arrow-key-prefix
"M-P" -> non-incremental-reverse-search-history
"M-R" -> revert-line
"M-T" -> transpose-words
"M-U" -> upcase-word
"M-Y" -> yank-pop
"M-C-Y" -> yank-nth-arg
"M-C-?" -> backward-delete-word
Emacs Control-X bindings
"C-XC-G" -> abort
"C-XC-R" -> re-read-init-file
"C-XC-U" -> undo
"C-X(" -> start-kbd-macro
"C-X)" -> end-kbd-macro
"C-Xe" -> call-last-kbd-macro
"C-XC-?" -> backward-kill-line
VI Insert Mode functions "C-D" -> vi-eof-maybe "C-H" -> backward-delete-char "C-I" -> complete "C-J" -> accept-line "C-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-[" -> vi-movement-mode " " 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" -> unix-word-rubout "C-Y" -> yank "C-[" -> abort " " -> forward-char "#" -> vi-comment "$" -> end-of-line "%" -> vi-match "&" -> vi-tilde-expand "*" -> vi-complete "+" -> down-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 "@" -> is undefined "A" -> vi-append-eol "B" -> vi-prev-word "C" -> vi-change-to "D" -> vi-delete-to "E" -> vi-end-word "F" -> vi-char-search "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" -> backward-delete-char "Y" -> vi-yank-to "\" -> vi-complete "^" -> vi-first-print "_" -> vi-yank-arg "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" -> prev-history "l" -> forward-char "n" -> vi-search-again "r" -> vi-change-char "s" -> vi-subst "t" -> vi-char-search "u" -> undo "w" -> vi-next-word "x" -> vi-delete "y" -> vi-yank-to "|" -> vi-column "~" -> vi-change-case
Chet Ramey, Case Western Reserve University
chet@ins.CWRU.Edu
Once you have determined that a bug actually exists, mail a bug report to bash-maintainers@prep.ai.MIT.Edu. If you have a fix, you are welcome to mail that as well! Suggestions and `philosophical' bug reports may be mailed to bug-bash@prep.ai.MIT.Edu or posted to the Usenet newsgroup gnu.bash.bug.
Comments and bug reports concerning this manual page should be directed to chet@ins.CWRU.Edu.
It's too big and too slow.