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diff --git a/readline-4.3.orig/doc/readline.info b/readline-4.3.orig/doc/readline.info new file mode 100644 index 0000000..57dbdfa --- /dev/null +++ b/readline-4.3.orig/doc/readline.info @@ -0,0 +1,3638 @@ +This is readline.info, produced by makeinfo version 4.1 from +/usr/homes/chet/src/bash/readline-src/doc/rlman.texinfo. + +INFO-DIR-SECTION Libraries +START-INFO-DIR-ENTRY +* Readline: (readline). The GNU readline library API +END-INFO-DIR-ENTRY + + This document describes the GNU Readline Library, a utility which +aids in the consistency of user interface across discrete programs that +need to provide a command line interface. + + Copyright (C) 1988-2002 Free Software Foundation, Inc. + + Permission is granted to make and distribute verbatim copies of this +manual provided the copyright notice and this permission notice pare +preserved on all copies. + + Permission is granted to copy and distribute modified versions of +this manual under the conditions for verbatim copying, provided that +the entire resulting derived work is distributed under the terms of a +permission notice identical to this one. + + Permission is granted to copy and distribute translations of this +manual into another language, under the above conditions for modified +versions, except that this permission notice may be stated in a +translation approved by the Free Software Foundation. + + +File: readline.info, Node: Top, Next: Command Line Editing, Up: (dir) + +GNU Readline Library +******************** + + This document describes the GNU Readline Library, a utility which +aids in the consistency of user interface across discrete programs that +need to provide a command line interface. + +* Menu: + +* Command Line Editing:: GNU Readline User's Manual. +* Programming with GNU Readline:: GNU Readline Programmer's Manual. +* Concept Index:: Index of concepts described in this manual. +* Function and Variable Index:: Index of externally visible functions + and variables. + + +File: readline.info, Node: Command Line Editing, Next: Programming with GNU Readline, Prev: Top, Up: Top + +Command Line Editing +******************** + + This chapter describes the basic features of the GNU command line +editing interface. + +* Menu: + +* Introduction and Notation:: Notation used in this text. +* Readline Interaction:: The minimum set of commands for editing a line. +* Readline Init File:: Customizing Readline from a user's view. +* Bindable Readline Commands:: A description of most of the Readline commands + available for binding +* Readline vi Mode:: A short description of how to make Readline + behave like the vi editor. + + +File: readline.info, Node: Introduction and Notation, Next: Readline Interaction, Up: Command Line Editing + +Introduction to Line Editing +============================ + + The following paragraphs describe the notation used to represent +keystrokes. + + The text `C-k' is read as `Control-K' and describes the character +produced when the <k> key is pressed while the Control key is depressed. + + The text `M-k' is read as `Meta-K' and describes the character +produced when the Meta key (if you have one) is depressed, and the <k> +key is pressed. The Meta key is labeled <ALT> on many keyboards. On +keyboards with two keys labeled <ALT> (usually to either side of the +space bar), the <ALT> on the left side is generally set to work as a +Meta key. The <ALT> key on the right may also be configured to work as +a Meta key or may be configured as some other modifier, such as a +Compose key for typing accented characters. + + If you do not have a Meta or <ALT> key, or another key working as a +Meta key, the identical keystroke can be generated by typing <ESC> +_first_, and then typing <k>. Either process is known as "metafying" +the <k> key. + + The text `M-C-k' is read as `Meta-Control-k' and describes the +character produced by "metafying" `C-k'. + + In addition, several keys have their own names. Specifically, +<DEL>, <ESC>, <LFD>, <SPC>, <RET>, and <TAB> all stand for themselves +when seen in this text, or in an init file (*note Readline Init File::). +If your keyboard lacks a <LFD> key, typing <C-j> will produce the +desired character. The <RET> key may be labeled <Return> or <Enter> on +some keyboards. + + +File: readline.info, Node: Readline Interaction, Next: Readline Init File, Prev: Introduction and Notation, Up: Command Line Editing + +Readline Interaction +==================== + + Often during an interactive session you type in a long line of text, +only to notice that the first word on the line is misspelled. The +Readline library gives you a set of commands for manipulating the text +as you type it in, allowing you to just fix your typo, and not forcing +you to retype the majority of the line. Using these editing commands, +you move the cursor to the place that needs correction, and delete or +insert the text of the corrections. Then, when you are satisfied with +the line, you simply press <RET>. You do not have to be at the end of +the line to press <RET>; the entire line is accepted regardless of the +location of the cursor within the line. + +* Menu: + +* Readline Bare Essentials:: The least you need to know about Readline. +* Readline Movement Commands:: Moving about the input line. +* Readline Killing Commands:: How to delete text, and how to get it back! +* Readline Arguments:: Giving numeric arguments to commands. +* Searching:: Searching through previous lines. + + +File: readline.info, Node: Readline Bare Essentials, Next: Readline Movement Commands, Up: Readline Interaction + +Readline Bare Essentials +------------------------ + + In order to enter characters into the line, simply type them. The +typed character appears where the cursor was, and then the cursor moves +one space to the right. If you mistype a character, you can use your +erase character to back up and delete the mistyped character. + + Sometimes you may mistype a character, and not notice the error +until you have typed several other characters. In that case, you can +type `C-b' to move the cursor to the left, and then correct your +mistake. Afterwards, you can move the cursor to the right with `C-f'. + + When you add text in the middle of a line, you will notice that +characters to the right of the cursor are `pushed over' to make room +for the text that you have inserted. Likewise, when you delete text +behind the cursor, characters to the right of the cursor are `pulled +back' to fill in the blank space created by the removal of the text. A +list of the bare essentials for editing the text of an input line +follows. + +`C-b' + Move back one character. + +`C-f' + Move forward one character. + +<DEL> or <Backspace> + Delete the character to the left of the cursor. + +`C-d' + Delete the character underneath the cursor. + +Printing characters + Insert the character into the line at the cursor. + +`C-_' or `C-x C-u' + Undo the last editing command. You can undo all the way back to an + empty line. + +(Depending on your configuration, the <Backspace> key be set to delete +the character to the left of the cursor and the <DEL> key set to delete +the character underneath the cursor, like `C-d', rather than the +character to the left of the cursor.) + + +File: readline.info, Node: Readline Movement Commands, Next: Readline Killing Commands, Prev: Readline Bare Essentials, Up: Readline Interaction + +Readline Movement Commands +-------------------------- + + The above table describes the most basic keystrokes that you need in +order to do editing of the input line. For your convenience, many +other commands have been added in addition to `C-b', `C-f', `C-d', and +<DEL>. Here are some commands for moving more rapidly about the line. + +`C-a' + Move to the start of the line. + +`C-e' + Move to the end of the line. + +`M-f' + Move forward a word, where a word is composed of letters and + digits. + +`M-b' + Move backward a word. + +`C-l' + Clear the screen, reprinting the current line at the top. + + Notice how `C-f' moves forward a character, while `M-f' moves +forward a word. It is a loose convention that control keystrokes +operate on characters while meta keystrokes operate on words. + + +File: readline.info, Node: Readline Killing Commands, Next: Readline Arguments, Prev: Readline Movement Commands, Up: Readline Interaction + +Readline Killing Commands +------------------------- + + "Killing" text means to delete the text from the line, but to save +it away for later use, usually by "yanking" (re-inserting) it back into +the line. (`Cut' and `paste' are more recent jargon for `kill' and +`yank'.) + + If the description for a command says that it `kills' text, then you +can be sure that you can get the text back in a different (or the same) +place later. + + When you use a kill command, the text is saved in a "kill-ring". +Any number of consecutive kills save all of the killed text together, so +that when you yank it back, you get it all. The kill ring is not line +specific; the text that you killed on a previously typed line is +available to be yanked back later, when you are typing another line. + + Here is the list of commands for killing text. + +`C-k' + Kill the text from the current cursor position to the end of the + line. + +`M-d' + Kill from the cursor 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 `M-f'. + +`M-<DEL>' + Kill from the cursor the start of the current word, or, if between + words, to the start of the previous word. Word boundaries are the + same as those used by `M-b'. + +`C-w' + Kill from the cursor to the previous whitespace. This is + different than `M-<DEL>' because the word boundaries differ. + + Here is how to "yank" the text back into the line. Yanking means to +copy the most-recently-killed text from the kill buffer. + +`C-y' + Yank the most recently killed text back into the buffer at the + cursor. + +`M-y' + Rotate the kill-ring, and yank the new top. You can only do this + if the prior command is `C-y' or `M-y'. + + +File: readline.info, Node: Readline Arguments, Next: Searching, Prev: Readline Killing Commands, Up: Readline Interaction + +Readline Arguments +------------------ + + You can pass numeric arguments to Readline commands. Sometimes the +argument acts as a repeat count, other times it is the sign of the +argument that is significant. If you pass a negative argument to a +command which normally acts in a forward direction, that command will +act in a backward direction. For example, to kill text back to the +start of the line, you might type `M-- C-k'. + + The general way to pass numeric arguments to a command is to type +meta digits before the command. If the first `digit' typed is a minus +sign (`-'), then the sign of the argument will be negative. Once you +have typed one meta digit to get the argument started, you can type the +remainder of the digits, and then the command. For example, to give +the `C-d' command an argument of 10, you could type `M-1 0 C-d', which +will delete the next ten characters on the input line. + + +File: readline.info, Node: Searching, Prev: Readline Arguments, Up: Readline Interaction + +Searching for Commands in the History +------------------------------------- + + Readline provides commands for searching through the command history +for lines containing a specified string. There are two search modes: +"incremental" and "non-incremental". + + Incremental searches begin before the user has finished typing the +search string. As each character of the search string is typed, +Readline displays the next entry from the history matching the string +typed so far. An incremental search requires only as many characters +as needed to find the desired history entry. To search backward in the +history for a particular string, type `C-r'. Typing `C-s' searches +forward through the history. The characters present in the value of +the `isearch-terminators' variable are used to terminate an incremental +search. If that variable has not been assigned a value, the <ESC> and +`C-J' characters will terminate an incremental search. `C-g' will +abort an incremental search and restore the original line. When the +search is terminated, the history entry containing the search string +becomes the current line. + + To find other matching entries in the history list, type `C-r' or +`C-s' as appropriate. This will search backward or forward in the +history for the next entry matching the search string typed so far. +Any other key sequence bound to a Readline command will terminate the +search and execute that command. For instance, a <RET> will terminate +the search and accept the line, thereby executing the command from the +history list. A movement command will terminate the search, make the +last line found the current line, and begin editing. + + Readline remembers the last incremental search string. If two +`C-r's are typed without any intervening characters defining a new +search string, any remembered search string is used. + + Non-incremental searches read the entire search string before +starting to search for matching history lines. The search string may be +typed by the user or be part of the contents of the current line. + + +File: readline.info, Node: Readline Init File, Next: Bindable Readline Commands, Prev: Readline Interaction, Up: Command Line Editing + +Readline Init File +================== + + Although the Readline library comes with a set of Emacs-like +keybindings installed by default, it is possible to use a different set +of keybindings. Any user can customize programs that use Readline by +putting commands in an "inputrc" file, conventionally in his home +directory. The name of this file is taken from the value of the +environment variable `INPUTRC'. 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 are set. + + In addition, the `C-x C-r' command re-reads this init file, thus +incorporating any changes that you might have made to it. + +* Menu: + +* Readline Init File Syntax:: Syntax for the commands in the inputrc file. + +* Conditional Init Constructs:: Conditional key bindings in the inputrc file. + +* Sample Init File:: An example inputrc file. + + +File: readline.info, Node: Readline Init File Syntax, Next: Conditional Init Constructs, Up: Readline Init File + +Readline Init File Syntax +------------------------- + + 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 +(*note Conditional Init Constructs::). Other lines denote variable +settings and key bindings. + +Variable Settings + You can modify the run-time behavior of Readline by altering the + values of variables in Readline using the `set' command within the + init file. The syntax is simple: + + set VARIABLE VALUE + + Here, for example, is how to change from the default Emacs-like + key binding to use `vi' line editing commands: + + set editing-mode vi + + Variable names and values, where appropriate, are recognized + without regard to case. + + A great deal of run-time behavior is changeable with the following + variables. + + `bell-style' + 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' (the default), + Readline attempts to ring the terminal's bell. + + `comment-begin' + The string to insert at the beginning of the line when the + `insert-comment' command is executed. The default value is + `"#"'. + + `completion-ignore-case' + If set to `on', Readline performs filename matching and + completion in a case-insensitive fashion. The default value + is `off'. + + `completion-query-items' + The number of possible completions that determines when the + user is asked whether he wants to see the list of + possibilities. If the number of possible completions is + greater than this value, Readline will ask the user whether + or not he wishes to view them; otherwise, they are simply + listed. This variable must be set to an integer value + greater than or equal to 0. The default limit is `100'. + + `convert-meta' + 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 an <ESC> character, converting them + to a meta-prefixed key sequence. The default value is `on'. + + `disable-completion' + 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'. The default is `off'. + + `editing-mode' + The `editing-mode' variable controls which default set of key + bindings is used. By default, Readline starts up in Emacs + editing mode, where the keystrokes are most similar to Emacs. + This variable can be set to either `emacs' or `vi'. + + `enable-keypad' + 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. The default is `off'. + + `expand-tilde' + If set to `on', tilde expansion is performed when Readline + attempts word completion. The default is `off'. + + If set to `on', the history code attempts to place point at + the same location on each history line retrived with + `previous-history' or `next-history'. + + `horizontal-scroll-mode' + This variable can be set to either `on' or `off'. Setting it + to `on' means that the text of the lines being edited will + scroll horizontally on a single screen line when they are + longer than the width of the screen, instead of wrapping onto + a new screen line. By default, this variable is set to `off'. + + `input-meta' + If set to `on', Readline will enable eight-bit input (it will + not clear the eighth bit in the characters it reads), + regardless of what the terminal claims it can support. The + default value is `off'. The name `meta-flag' is a synonym + for this variable. + + `isearch-terminators' + The string of characters that should terminate an incremental + search without subsequently executing the character as a + command (*note Searching::). If this variable has not been + given a value, the characters <ESC> and `C-J' will terminate + an incremental search. + + `keymap' + Sets Readline's idea of the current keymap for key binding + commands. Acceptable `keymap' names are `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 the `editing-mode' + variable also affects the default keymap. + + `mark-directories' + If set to `on', completed directory names have a slash + appended. The default is `on'. + + `mark-modified-lines' + This variable, when set to `on', causes Readline to display an + asterisk (`*') at the start of history lines which have been + modified. This variable is `off' by default. + + `mark-symlinked-directories' + If set to `on', completed names which are symbolic links to + directories have a slash appended (subject to the value of + `mark-directories'). The default is `off'. + + `match-hidden-files' + This variable, when set to `on', causes Readline to match + files whose names begin with a `.' (hidden files) when + performing filename completion, unless the leading `.' is + supplied by the user in the filename to be completed. This + variable is `on' by default. + + `output-meta' + 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'. + + `page-completions' + If set to `on', Readline uses an internal `more'-like pager + to display a screenful of possible completions at a time. + This variable is `on' by default. + + `print-completions-horizontally' + If set to `on', Readline will display completions with matches + sorted horizontally in alphabetical order, rather than down + the screen. The default is `off'. + + `show-all-if-ambiguous' + 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. The default value is `off'. + + `visible-stats' + If set to `on', a character denoting a file's type is + appended to the filename when listing possible completions. + The default is `off'. + +Key Bindings + The syntax for controlling key bindings in the init file is + simple. First you need to find the name of the command that you + want to change. The following sections contain tables of the + command name, the default keybinding, if any, and a short + description of what the command does. + + Once you know the name of the command, simply place on a line in + the init file the name of the key you wish to bind the command to, + a colon, and then the name of the command. The name of the key + can be expressed in different ways, depending on what you find most + comfortable. + + In addition to command names, readline allows keys to be bound to + a string that is inserted when the key is pressed (a MACRO). + + 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). + + A number of symbolic character names are recognized while + processing this key binding syntax: DEL, ESC, ESCAPE, LFD, + NEWLINE, RET, RETURN, RUBOUT, SPACE, SPC, and TAB. + + "KEYSEQ": FUNCTION-NAME or MACRO + KEYSEQ differs from KEYNAME above in that strings denoting an + entire key sequence can be specified, by placing the key + sequence in double quotes. Some GNU Emacs style key escapes + can be used, as in the following example, but the special + character names are not recognized. + + "\C-u": universal-argument + "\C-x\C-r": re-read-init-file + "\e[11~": "Function Key 1" + + In the above example, `C-u' is again bound to the function + `universal-argument' (just as it was in the first example), + `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 following GNU Emacs style escape sequences are available when + specifying key sequences: + + `\C-' + control prefix + + `\M-' + meta prefix + + `\e' + an escape character + + `\\' + backslash + + `\"' + <">, a double quotation mark + + `\'' + <'>, a single quote or apostrophe + + In addition to the GNU Emacs style escape sequences, a second set + of backslash escapes is available: + + `\a' + alert (bell) + + `\b' + backspace + + `\d' + delete + + `\f' + form feed + + `\n' + newline + + `\r' + carriage return + + `\t' + horizontal tab + + `\v' + vertical tab + + `\NNN' + the eight-bit character whose value is the octal value NNN + (one to three digits) + + `\xHH' + the eight-bit character whose value is the hexadecimal value + HH (one or two hex digits) + + When entering the text of a macro, single or double quotes must be + used to indicate a macro definition. Unquoted text is assumed to + be a function name. In the macro body, the backslash escapes + described above are expanded. Backslash will quote any other + character in the macro text, including `"' and `''. For example, + the following binding will make `C-x \' insert a single `\' into + the line: + "\C-x\\": "\\" + + +File: readline.info, Node: Conditional Init Constructs, Next: Sample Init File, Prev: Readline Init File Syntax, Up: Readline Init File + +Conditional Init 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 `$if' construct allows bindings to be made based on the + editing mode, the terminal being used, or the application using + Readline. The text of the test extends to the end of the line; no + characters are required to isolate it. + + `mode' + The `mode=' form of the `$if' directive is used to test + whether Readline is in `emacs' or `vi' mode. This may be + used in conjunction with the `set keymap' command, for + instance, to set bindings in the `emacs-standard' and + `emacs-ctlx' keymaps only if Readline is starting out in + `emacs' mode. + + `term' + The `term=' form may be used to include terminal-specific key + bindings, perhaps to bind the key sequences output by the + terminal's function keys. The word on the right side of the + `=' is tested against both the full name of the terminal and + the portion of the terminal name before the first `-'. This + allows `sun' to match both `sun' and `sun-cmd', for instance. + + `application' + The APPLICATION construct is used to include + application-specific settings. Each program using the + Readline library sets the APPLICATION NAME, and you 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\"" + $endif + +`$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 reads from `/etc/inputrc': + $include /etc/inputrc + + +File: readline.info, Node: Sample Init File, Prev: Conditional Init Constructs, Up: Readline Init File + +Sample Init File +---------------- + + Here is an example of an INPUTRC file. This illustrates key +binding, variable assignment, and conditional syntax. + + + # This file controls the behaviour of line input editing for + # programs that use the GNU Readline library. Existing + # programs include FTP, Bash, and GDB. + # + # You can re-read the inputrc file with C-x C-r. + # Lines beginning with '#' are comments. + # + # First, include any systemwide bindings and variable + # assignments from /etc/Inputrc + $include /etc/Inputrc + + # + # Set various bindings for emacs mode. + + set editing-mode emacs + + $if mode=emacs + + Meta-Control-h: backward-kill-word Text after the function name is ignored + + # + # Arrow keys in keypad mode + # + #"\M-OD": backward-char + #"\M-OC": forward-char + #"\M-OA": previous-history + #"\M-OB": next-history + # + # Arrow keys in ANSI mode + # + "\M-[D": backward-char + "\M-[C": forward-char + "\M-[A": previous-history + "\M-[B": next-history + # + # Arrow keys in 8 bit keypad mode + # + #"\M-\C-OD": backward-char + #"\M-\C-OC": forward-char + #"\M-\C-OA": previous-history + #"\M-\C-OB": next-history + # + # Arrow keys in 8 bit ANSI mode + # + #"\M-\C-[D": backward-char + #"\M-\C-[C": forward-char + #"\M-\C-[A": previous-history + #"\M-\C-[B": next-history + + C-q: quoted-insert + + $endif + + # An old-style binding. This happens to be the default. + TAB: complete + + # Macros that are convenient for shell interaction + $if Bash + # edit the path + "\C-xp": "PATH=${PATH}\e\C-e\C-a\ef\C-f" + # prepare to type a quoted word -- + # insert open and close double quotes + # and move to just after the open quote + "\C-x\"": "\"\"\C-b" + # insert a backslash (testing backslash escapes + # in sequences and macros) + "\C-x\\": "\\" + # Quote the current or previous word + "\C-xq": "\eb\"\ef\"" + # Add a binding to refresh the line, which is unbound + "\C-xr": redraw-current-line + # Edit variable on current line. + "\M-\C-v": "\C-a\C-k$\C-y\M-\C-e\C-a\C-y=" + $endif + + # use a visible bell if one is available + set bell-style visible + + # don't strip characters to 7 bits when reading + set input-meta on + + # allow iso-latin1 characters to be inserted rather + # than converted to prefix-meta sequences + set convert-meta off + + # display characters with the eighth bit set directly + # rather than as meta-prefixed characters + set output-meta on + + # if there are more than 150 possible completions for + # a word, ask the user if he wants to see all of them + set completion-query-items 150 + + # For FTP + $if Ftp + "\C-xg": "get \M-?" + "\C-xt": "put \M-?" + "\M-.": yank-last-arg + $endif + + +File: readline.info, Node: Bindable Readline Commands, Next: Readline vi Mode, Prev: Readline Init File, Up: Command Line Editing + +Bindable Readline Commands +========================== + +* Menu: + +* Commands For Moving:: Moving about the line. +* Commands For History:: Getting at previous lines. +* Commands For Text:: Commands for changing text. +* Commands For Killing:: Commands for killing and yanking. +* Numeric Arguments:: Specifying numeric arguments, repeat counts. +* Commands For Completion:: Getting Readline to do the typing for you. +* Keyboard Macros:: Saving and re-executing typed characters +* Miscellaneous Commands:: Other miscellaneous commands. + + This section describes Readline commands that may be bound to key +sequences. Command names without an accompanying key sequence are +unbound by default. + + In the following descriptions, "point" refers to the current cursor +position, and "mark" refers to a cursor position saved by the +`set-mark' command. The text between the point and mark is referred to +as the "region". + + +File: readline.info, Node: Commands For Moving, Next: Commands For History, Up: Bindable Readline Commands + +Commands For Moving +------------------- + +`beginning-of-line (C-a)' + Move to the start of the current line. + +`end-of-line (C-e)' + Move to the end of the line. + +`forward-char (C-f)' + Move forward a character. + +`backward-char (C-b)' + Move back a character. + +`forward-word (M-f)' + Move forward to the end of the next word. Words are composed of + letters and digits. + +`backward-word (M-b)' + Move back to the start of the current or previous word. Words are + composed of letters and digits. + +`clear-screen (C-l)' + Clear the screen and redraw the current line, leaving the current + line at the top of the screen. + +`redraw-current-line ()' + Refresh the current line. By default, this is unbound. + + +File: readline.info, Node: Commands For History, Next: Commands For Text, Prev: Commands For Moving, Up: Bindable Readline Commands + +Commands For Manipulating The History +------------------------------------- + +`accept-line (Newline or Return)' + Accept the line regardless of where the cursor is. If this line is + non-empty, it may be added to the history list for future recall + with `add_history()'. If this line is a modified history line, + the history line is restored to its original state. + +`previous-history (C-p)' + Move `back' through the history list, fetching the previous + command. + +`next-history (C-n)' + Move `forward' through the history list, fetching the next command. + +`beginning-of-history (M-<)' + Move to the first line in the history. + +`end-of-history (M->)' + Move to the end of the input history, i.e., the line currently + being entered. + +`reverse-search-history (C-r)' + Search backward starting at the current line and moving `up' + through the history as necessary. This is an incremental search. + +`forward-search-history (C-s)' + Search forward starting at the current line and moving `down' + through the the history as necessary. This is an incremental + search. + +`non-incremental-reverse-search-history (M-p)' + Search backward starting at the current line and moving `up' + through the history as necessary using a non-incremental search + for a string supplied by the user. + +`non-incremental-forward-search-history (M-n)' + Search forward starting at the current line and moving `down' + through the the history as necessary using a non-incremental search + for a string supplied by the user. + +`history-search-forward ()' + Search forward through the history for the string of characters + between the start of the current line and the point. This is a + non-incremental search. By default, this command is unbound. + +`history-search-backward ()' + Search backward through the history for the string of characters + between the start of the current line and the point. This is a + non-incremental search. By default, this command is unbound. + +`yank-nth-arg (M-C-y)' + Insert the first argument to the previous command (usually the + second word on the previous line) at point. With an argument N, + insert the Nth word from the previous command (the words in the + previous command begin with word 0). A negative argument inserts + the Nth word from the end of the previous command. + +`yank-last-arg (M-. or M-_)' + Insert last argument to the previous command (the last word of the + previous history entry). With an argument, behave exactly like + `yank-nth-arg'. Successive calls to `yank-last-arg' move back + through the history list, inserting the last argument of each line + in turn. + + +File: readline.info, Node: Commands For Text, Next: Commands For Killing, Prev: Commands For History, Up: Bindable Readline Commands + +Commands For Changing Text +-------------------------- + +`delete-char (C-d)' + Delete the character at point. If point is at the beginning of + the line, there are no characters in the line, and the last + character typed was not bound to `delete-char', then return EOF. + +`backward-delete-char (Rubout)' + Delete the character behind the cursor. A numeric argument means + to kill the characters instead of deleting them. + +`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. By default, this is not bound to a key. + +`quoted-insert (C-q or C-v)' + Add the next character typed to the line verbatim. This is how to + insert key sequences like `C-q', for example. + +`tab-insert (M-<TAB>)' + Insert a tab character. + +`self-insert (a, b, A, 1, !, ...)' + Insert yourself. + +`transpose-chars (C-t)' + Drag the character before the cursor forward over the character at + the cursor, moving the cursor forward as well. If the insertion + point is at the end of the line, then this transposes the last two + characters of the line. Negative arguments have no effect. + +`transpose-words (M-t)' + Drag the word before point past the word after point, moving point + past that word as well. If the insertion point is at the end of + the line, this transposes the last two words on the line. + +`upcase-word (M-u)' + Uppercase the current (or following) word. With a negative + argument, uppercase the previous word, but do not move the cursor. + +`downcase-word (M-l)' + Lowercase the current (or following) word. With a negative + argument, lowercase the previous word, but do not move the cursor. + +`capitalize-word (M-c)' + Capitalize the current (or following) word. With a negative + argument, capitalize the previous word, but do not move the cursor. + +`overwrite-mode ()' + Toggle overwrite mode. With an explicit positive numeric argument, + switches to overwrite mode. With an explicit non-positive numeric + argument, switches to insert mode. This command affects only + `emacs' mode; `vi' mode does overwrite differently. Each call to + `readline()' starts in insert mode. + + In overwrite mode, characters bound to `self-insert' replace the + text at point rather than pushing the text to the right. + Characters bound to `backward-delete-char' replace the character + before point with a space. + + By default, this command is unbound. + + +File: readline.info, Node: Commands For Killing, Next: Numeric Arguments, Prev: Commands For Text, Up: Bindable Readline Commands + +Killing And Yanking +------------------- + +`kill-line (C-k)' + Kill the text from point to the end of the line. + +`backward-kill-line (C-x Rubout)' + Kill backward to the beginning of the line. + +`unix-line-discard (C-u)' + Kill backward from the cursor to the beginning of the current line. + +`kill-whole-line ()' + Kill all characters on the current line, no matter where point is. + By default, this is unbound. + +`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 `forward-word'. + +`backward-kill-word (M-<DEL>)' + Kill the word behind point. Word boundaries are the same as + `backward-word'. + +`unix-word-rubout (C-w)' + Kill the word behind point, using white space as a word boundary. + The killed text is saved on the kill-ring. + +`delete-horizontal-space ()' + Delete all spaces and tabs around point. By default, this is + unbound. + +`kill-region ()' + Kill the text in the current region. By default, this command is + unbound. + +`copy-region-as-kill ()' + Copy the text in the region to the kill buffer, so it can be yanked + right away. By default, this command is unbound. + +`copy-backward-word ()' + Copy the word before point to the kill buffer. The word + boundaries are the same as `backward-word'. By default, this + command is unbound. + +`copy-forward-word ()' + Copy the word following point to the kill buffer. The word + boundaries are the same as `forward-word'. By default, this + command is unbound. + +`yank (C-y)' + Yank the top of the kill ring into the buffer at point. + +`yank-pop (M-y)' + Rotate the kill-ring, and yank the new top. You can only do this + if the prior command is `yank' or `yank-pop'. + + +File: readline.info, Node: Numeric Arguments, Next: Commands For Completion, Prev: Commands For Killing, Up: Bindable Readline Commands + +Specifying Numeric Arguments +---------------------------- + +`digit-argument (M-0, M-1, ... M--)' + Add this digit to the argument already accumulating, or start a new + argument. `M--' starts a negative argument. + +`universal-argument ()' + This is another way to specify an argument. If this command is + followed by one or more digits, optionally with a leading minus + sign, those digits define the argument. If the command is + followed by digits, executing `universal-argument' again ends the + numeric argument, but is otherwise ignored. As a special case, if + this command is immediately followed by a character that is + neither a digit or 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. By default, this is not bound to a key. + + +File: readline.info, Node: Commands For Completion, Next: Keyboard Macros, Prev: Numeric Arguments, Up: Bindable Readline Commands + +Letting Readline Type For You +----------------------------- + +`complete (<TAB>)' + Attempt to perform completion on the text before point. The + actual completion performed is application-specific. The default + is filename completion. + +`possible-completions (M-?)' + List the possible completions of the text before point. + +`insert-completions (M-*)' + Insert all completions of the text before point that would have + been generated by `possible-completions'. + +`menu-complete ()' + Similar to `complete', but replaces the word to be completed with + a single match from the list of possible completions. Repeated + execution of `menu-complete' steps through the list of possible + completions, inserting each match in turn. At the end of the list + of completions, the bell is rung (subject to the setting of + `bell-style') and the original text is restored. An argument of N + moves N positions forward in the list of matches; a negative + argument may be used to move backward through the list. This + command is intended to be bound to <TAB>, but is unbound by + default. + +`delete-char-or-list ()' + Deletes the character under the cursor if not at the beginning or + end of the line (like `delete-char'). If at the end of the line, + behaves identically to `possible-completions'. This command is + unbound by default. + + +File: readline.info, Node: Keyboard Macros, Next: Miscellaneous Commands, Prev: Commands For Completion, Up: Bindable Readline Commands + +Keyboard Macros +--------------- + +`start-kbd-macro (C-x ()' + Begin saving the characters typed into the current keyboard macro. + +`end-kbd-macro (C-x ))' + Stop saving the characters typed into the current keyboard macro + and save the definition. + +`call-last-kbd-macro (C-x e)' + Re-execute the last keyboard macro defined, by making the + characters in the macro appear as if typed at the keyboard. + + +File: readline.info, Node: Miscellaneous Commands, Prev: Keyboard Macros, Up: Bindable Readline Commands + +Some Miscellaneous Commands +--------------------------- + +`re-read-init-file (C-x C-r)' + Read in the contents of the INPUTRC file, and incorporate any + bindings or variable assignments found there. + +`abort (C-g)' + Abort the current editing command and ring the terminal's bell + (subject to the setting of `bell-style'). + +`do-uppercase-version (M-a, M-b, M-X, ...)' + If the metafied character X is lowercase, run the command that is + bound to the corresponding uppercase character. + +`prefix-meta (<ESC>)' + Metafy the next character typed. This is for keyboards without a + meta key. Typing `<ESC> f' is equivalent to typing `M-f'. + +`undo (C-_ or C-x C-u)' + Incremental undo, separately remembered for each line. + +`revert-line (M-r)' + Undo all changes made to this line. This is like executing the + `undo' command enough times to get back to the beginning. + +`tilde-expand (M-~)' + Perform tilde expansion on the current word. + +`set-mark (C-@)' + Set the mark to the point. If a numeric argument is supplied, the + mark is set to that position. + +`exchange-point-and-mark (C-x C-x)' + Swap the point with the mark. The current cursor position is set + to the saved position, and the old cursor position is saved as the + mark. + +`character-search (C-])' + A character is read and point is moved to the next occurrence of + that character. A negative count searches for previous + occurrences. + +`character-search-backward (M-C-])' + A character is read and point is moved to the previous occurrence + of that character. A negative count searches for subsequent + occurrences. + +`insert-comment (M-#)' + Without a numeric argument, the value of the `comment-begin' + variable is inserted at the beginning of the current line. If a + numeric argument is supplied, this command acts as a toggle: if + the characters at the beginning of the line do not match the value + of `comment-begin', the value is inserted, otherwise the + characters in `comment-begin' are deleted from the beginning of + the line. In either case, the line is accepted as if a newline + had been typed. + +`dump-functions ()' + Print all of the functions and their key bindings to the Readline + output stream. If a numeric argument is supplied, the output is + formatted in such a way that it can be made part of an INPUTRC + file. This command is unbound by default. + +`dump-variables ()' + Print all of the settable variables and their values to the + Readline output stream. If a numeric argument is supplied, the + output is formatted in such a way that it can be made part of an + INPUTRC file. This command is unbound by default. + +`dump-macros ()' + Print all of the Readline key sequences bound to macros and the + strings they output. If a numeric argument is supplied, the + output is formatted in such a way that it can be made part of an + INPUTRC file. This command is unbound by default. + +`emacs-editing-mode (C-e)' + When in `vi' command mode, this causes a switch to `emacs' editing + mode. + +`vi-editing-mode (M-C-j)' + When in `emacs' editing mode, this causes a switch to `vi' editing + mode. + + +File: readline.info, Node: Readline vi Mode, Prev: Bindable Readline Commands, Up: Command Line Editing + +Readline vi Mode +================ + + While the Readline library does not have a full set of `vi' editing +functions, it does contain enough to allow simple editing of the line. +The Readline `vi' mode behaves as specified in the POSIX 1003.2 +standard. + + In order to switch interactively between `emacs' and `vi' editing +modes, use the command `M-C-j' (bound to emacs-editing-mode when in +`vi' mode and to vi-editing-mode in `emacs' mode). The Readline +default is `emacs' mode. + + When you enter a line in `vi' mode, you are already placed in +`insertion' mode, as if you had typed an `i'. Pressing <ESC> switches +you into `command' mode, where you can edit the text of the line with +the standard `vi' movement keys, move to previous history lines with +`k' and subsequent lines with `j', and so forth. + + This document describes the GNU Readline Library, a utility for +aiding in the consitency of user interface across discrete programs +that need to provide a command line interface. + + Copyright (C) 1988-2002 Free Software Foundation, Inc. + + Permission is granted to make and distribute verbatim copies of this +manual provided the copyright notice and this permission notice pare +preserved on all copies. + + Permission is granted to copy and distribute modified versions of +this manual under the conditions for verbatim copying, provided that +the entire resulting derived work is distributed under the terms of a +permission notice identical to this one. + + Permission is granted to copy and distribute translations of this +manual into another language, under the above conditions for modified +versions, except that this permission notice may be stated in a +translation approved by the Foundation. + + +File: readline.info, Node: Programming with GNU Readline, Next: Concept Index, Prev: Command Line Editing, Up: Top + +Programming with GNU Readline +***************************** + + This chapter describes the interface between the GNU Readline +Library and other programs. If you are a programmer, and you wish to +include the features found in GNU Readline such as completion, line +editing, and interactive history manipulation in your own programs, +this section is for you. + +* Menu: + +* Basic Behavior:: Using the default behavior of Readline. +* Custom Functions:: Adding your own functions to Readline. +* Readline Variables:: Variables accessible to custom + functions. +* Readline Convenience Functions:: Functions which Readline supplies to + aid in writing your own custom + functions. +* Readline Signal Handling:: How Readline behaves when it receives signals. +* Custom Completers:: Supplanting or supplementing Readline's + completion functions. + + +File: readline.info, Node: Basic Behavior, Next: Custom Functions, Up: Programming with GNU Readline + +Basic Behavior +============== + + Many programs provide a command line interface, such as `mail', +`ftp', and `sh'. For such programs, the default behaviour of Readline +is sufficient. This section describes how to use Readline in the +simplest way possible, perhaps to replace calls in your code to +`gets()' or `fgets()'. + + The function `readline()' prints a prompt PROMPT and then reads and +returns a single line of text from the user. If PROMPT is `NULL' or +the empty string, no prompt is displayed. The line `readline' returns +is allocated with `malloc()'; the caller should `free()' the line when +it has finished with it. The declaration for `readline' in ANSI C is + + `char *readline (const char *PROMPT);' + +So, one might say + `char *line = readline ("Enter a line: ");' + +in order to read a line of text from the user. The line returned has +the final newline removed, so only the text remains. + + If `readline' encounters an `EOF' while reading the line, and the +line is empty at that point, then `(char *)NULL' is returned. +Otherwise, the line is ended just as if a newline had been typed. + + If you want the user to be able to get at the line later, (with +<C-p> for example), you must call `add_history()' to save the line away +in a "history" list of such lines. + + `add_history (line)'; + +For full details on the GNU History Library, see the associated manual. + + It is preferable to avoid saving empty lines on the history list, +since users rarely have a burning need to reuse a blank line. Here is +a function which usefully replaces the standard `gets()' library +function, and has the advantage of no static buffer to overflow: + + /* A static variable for holding the line. */ + static char *line_read = (char *)NULL; + + /* Read a string, and return a pointer to it. + Returns NULL on EOF. */ + char * + rl_gets () + { + /* If the buffer has already been allocated, + return the memory to the free pool. */ + if (line_read) + { + free (line_read); + line_read = (char *)NULL; + } + + /* Get a line from the user. */ + line_read = readline (""); + + /* If the line has any text in it, + save it on the history. */ + if (line_read && *line_read) + add_history (line_read); + + return (line_read); + } + + This function gives the user the default behaviour of <TAB> +completion: completion on file names. If you do not want Readline to +complete on filenames, you can change the binding of the <TAB> key with +`rl_bind_key()'. + + `int rl_bind_key (int KEY, rl_command_func_t *FUNCTION);' + + `rl_bind_key()' takes two arguments: KEY is the character that you +want to bind, and FUNCTION is the address of the function to call when +KEY is pressed. Binding <TAB> to `rl_insert()' makes <TAB> insert +itself. `rl_bind_key()' returns non-zero if KEY is not a valid ASCII +character code (between 0 and 255). + + Thus, to disable the default <TAB> behavior, the following suffices: + `rl_bind_key ('\t', rl_insert);' + + This code should be executed once at the start of your program; you +might write a function called `initialize_readline()' which performs +this and other desired initializations, such as installing custom +completers (*note Custom Completers::). + + +File: readline.info, Node: Custom Functions, Next: Readline Variables, Prev: Basic Behavior, Up: Programming with GNU Readline + +Custom Functions +================ + + Readline provides many functions for manipulating the text of the +line, but it isn't possible to anticipate the needs of all programs. +This section describes the various functions and variables defined +within the Readline library which allow a user program to add +customized functionality to Readline. + + Before declaring any functions that customize Readline's behavior, or +using any functionality Readline provides in other code, an application +writer should include the file `<readline/readline.h>' in any file that +uses Readline's features. Since some of the definitions in +`readline.h' use the `stdio' library, the file `<stdio.h>' should be +included before `readline.h'. + + `readline.h' defines a C preprocessor variable that should be +treated as an integer, `RL_READLINE_VERSION', which may be used to +conditionally compile application code depending on the installed +Readline version. The value is a hexadecimal encoding of the major and +minor version numbers of the library, of the form 0xMMMM. MM is the +two-digit major version number; MM is the two-digit minor version +number. For Readline 4.2, for example, the value of +`RL_READLINE_VERSION' would be `0x0402'. + +* Menu: + +* Readline Typedefs:: C declarations to make code readable. +* Function Writing:: Variables and calling conventions. + + +File: readline.info, Node: Readline Typedefs, Next: Function Writing, Up: Custom Functions + +Readline Typedefs +----------------- + + For readabilty, we declare a number of new object types, all pointers +to functions. + + The reason for declaring these new types is to make it easier to +write code describing pointers to C functions with appropriately +prototyped arguments and return values. + + For instance, say we want to declare a variable FUNC as a pointer to +a function which takes two `int' arguments and returns an `int' (this +is the type of all of the Readline bindable functions). Instead of the +classic C declaration + + `int (*func)();' + +or the ANSI-C style declaration + + `int (*func)(int, int);' + +we may write + + `rl_command_func_t *func;' + + The full list of function pointer types available is + +`typedef int rl_command_func_t (int, int);' + +`typedef char *rl_compentry_func_t (const char *, int);' + +`typedef char **rl_completion_func_t (const char *, int, int);' + +`typedef char *rl_quote_func_t (char *, int, char *);' + +`typedef char *rl_dequote_func_t (char *, int);' + +`typedef int rl_compignore_func_t (char **);' + +`typedef void rl_compdisp_func_t (char **, int, int);' + +`typedef int rl_hook_func_t (void);' + +`typedef int rl_getc_func_t (FILE *);' + +`typedef int rl_linebuf_func_t (char *, int);' + +`typedef int rl_intfunc_t (int);' + +`#define rl_ivoidfunc_t rl_hook_func_t' + +`typedef int rl_icpfunc_t (char *);' + +`typedef int rl_icppfunc_t (char **);' + +`typedef void rl_voidfunc_t (void);' + +`typedef void rl_vintfunc_t (int);' + +`typedef void rl_vcpfunc_t (char *);' + +`typedef void rl_vcppfunc_t (char **);' + +File: readline.info, Node: Function Writing, Prev: Readline Typedefs, Up: Custom Functions + +Writing a New Function +---------------------- + + In order to write new functions for Readline, you need to know the +calling conventions for keyboard-invoked functions, and the names of the +variables that describe the current state of the line read so far. + + The calling sequence for a command `foo' looks like + + `int foo (int count, int key)' + +where COUNT is the numeric argument (or 1 if defaulted) and KEY is the +key that invoked this function. + + It is completely up to the function as to what should be done with +the numeric argument. Some functions use it as a repeat count, some as +a flag, and others to choose alternate behavior (refreshing the current +line as opposed to refreshing the screen, for example). Some choose to +ignore it. In general, if a function uses the numeric argument as a +repeat count, it should be able to do something useful with both +negative and positive arguments. At the very least, it should be aware +that it can be passed a negative argument. + + A command function should return 0 if its action completes +successfully, and a non-zero value if some error occurs. + + +File: readline.info, Node: Readline Variables, Next: Readline Convenience Functions, Prev: Custom Functions, Up: Programming with GNU Readline + +Readline Variables +================== + + These variables are available to function writers. + + - Variable: char * rl_line_buffer + This is the line gathered so far. You are welcome to modify the + contents of the line, but see *Note Allowing Undoing::. The + function `rl_extend_line_buffer' is available to increase the + memory allocated to `rl_line_buffer'. + + - Variable: int rl_point + The offset of the current cursor position in `rl_line_buffer' (the + _point_). + + - Variable: int rl_end + The number of characters present in `rl_line_buffer'. When + `rl_point' is at the end of the line, `rl_point' and `rl_end' are + equal. + + - Variable: int rl_mark + The MARK (saved position) in the current line. If set, the mark + and point define a _region_. + + - Variable: int rl_done + Setting this to a non-zero value causes Readline to return the + current line immediately. + + - Variable: int rl_num_chars_to_read + Setting this to a positive value before calling `readline()' causes + Readline to return after accepting that many characters, rather + than reading up to a character bound to `accept-line'. + + - Variable: int rl_pending_input + Setting this to a value makes it the next keystroke read. This is + a way to stuff a single character into the input stream. + + - Variable: int rl_dispatching + Set to a non-zero value if a function is being called from a key + binding; zero otherwise. Application functions can test this to + discover whether they were called directly or by Readline's + dispatching mechanism. + + - Variable: int rl_erase_empty_line + Setting this to a non-zero value causes Readline to completely + erase the current line, including any prompt, any time a newline + is typed as the only character on an otherwise-empty line. The + cursor is moved to the beginning of the newly-blank line. + + - Variable: char * rl_prompt + The prompt Readline uses. This is set from the argument to + `readline()', and should not be assigned to directly. The + `rl_set_prompt()' function (*note Redisplay::) may be used to + modify the prompt string after calling `readline()'. + + - Variable: int rl_already_prompted + If an application wishes to display the prompt itself, rather than + have Readline do it the first time `readline()' is called, it + should set this variable to a non-zero value after displaying the + prompt. The prompt must also be passed as the argument to + `readline()' so the redisplay functions can update the display + properly. The calling application is responsible for managing the + value; Readline never sets it. + + - Variable: const char * rl_library_version + The version number of this revision of the library. + + - Variable: int rl_readline_version + An integer encoding the current version of the library. The + encoding is of the form 0xMMMM, where MM is the two-digit major + version number, and MM is the two-digit minor version number. For + example, for Readline-4.2, `rl_readline_version' would have the + value 0x0402. + + - Variable: int rl_gnu_readline_p + Always set to 1, denoting that this is GNU readline rather than + some emulation. + + - Variable: const char * rl_terminal_name + The terminal type, used for initialization. If not set by the + application, Readline sets this to the value of the `TERM' + environment variable the first time it is called. + + - Variable: const char * rl_readline_name + This variable is set to a unique name by each application using + Readline. The value allows conditional parsing of the inputrc file + (*note Conditional Init Constructs::). + + - Variable: FILE * rl_instream + The stdio stream from which Readline reads input. If `NULL', + Readline defaults to STDIN. + + - Variable: FILE * rl_outstream + The stdio stream to which Readline performs output. If `NULL', + Readline defaults to STDOUT. + + - Variable: rl_command_func_t * rl_last_func + The address of the last command function Readline executed. May + be used to test whether or not a function is being executed twice + in succession, for example. + + - Variable: rl_hook_func_t * rl_startup_hook + If non-zero, this is the address of a function to call just before + `readline' prints the first prompt. + + - Variable: rl_hook_func_t * rl_pre_input_hook + If non-zero, this is the address of a function to call after the + first prompt has been printed and just before `readline' starts + reading input characters. + + - Variable: rl_hook_func_t * rl_event_hook + If non-zero, this is the address of a function to call periodically + when Readline is waiting for terminal input. By default, this + will be called at most ten times a second if there is no keyboard + input. + + - Variable: rl_getc_func_t * rl_getc_function + If non-zero, Readline will call indirectly through this pointer to + get a character from the input stream. By default, it is set to + `rl_getc', the default Readline character input function (*note + Character Input::). + + - Variable: rl_voidfunc_t * rl_redisplay_function + If non-zero, Readline will call indirectly through this pointer to + update the display with the current contents of the editing buffer. + By default, it is set to `rl_redisplay', the default Readline + redisplay function (*note Redisplay::). + + - Variable: rl_vintfunc_t * rl_prep_term_function + If non-zero, Readline will call indirectly through this pointer to + initialize the terminal. The function takes a single argument, an + `int' flag that says whether or not to use eight-bit characters. + By default, this is set to `rl_prep_terminal' (*note Terminal + Management::). + + - Variable: rl_voidfunc_t * rl_deprep_term_function + If non-zero, Readline will call indirectly through this pointer to + reset the terminal. This function should undo the effects of + `rl_prep_term_function'. By default, this is set to + `rl_deprep_terminal' (*note Terminal Management::). + + - Variable: Keymap rl_executing_keymap + This variable is set to the keymap (*note Keymaps::) in which the + currently executing readline function was found. + + - Variable: Keymap rl_binding_keymap + This variable is set to the keymap (*note Keymaps::) in which the + last key binding occurred. + + - Variable: char * rl_executing_macro + This variable is set to the text of any currently-executing macro. + + - Variable: int rl_readline_state + A variable with bit values that encapsulate the current Readline + state. A bit is set with the `RL_SETSTATE' macro, and unset with + the `RL_UNSETSTATE' macro. Use the `RL_ISSTATE' macro to test + whether a particular state bit is set. Current state bits include: + + `RL_STATE_NONE' + Readline has not yet been called, nor has it begun to + intialize. + + `RL_STATE_INITIALIZING' + Readline is initializing its internal data structures. + + `RL_STATE_INITIALIZED' + Readline has completed its initialization. + + `RL_STATE_TERMPREPPED' + Readline has modified the terminal modes to do its own input + and redisplay. + + `RL_STATE_READCMD' + Readline is reading a command from the keyboard. + + `RL_STATE_METANEXT' + Readline is reading more input after reading the meta-prefix + character. + + `RL_STATE_DISPATCHING' + Readline is dispatching to a command. + + `RL_STATE_MOREINPUT' + Readline is reading more input while executing an editing + command. + + `RL_STATE_ISEARCH' + Readline is performing an incremental history search. + + `RL_STATE_NSEARCH' + Readline is performing a non-incremental history search. + + `RL_STATE_SEARCH' + Readline is searching backward or forward through the history + for a string. + + `RL_STATE_NUMERICARG' + Readline is reading a numeric argument. + + `RL_STATE_MACROINPUT' + Readline is currently getting its input from a + previously-defined keyboard macro. + + `RL_STATE_MACRODEF' + Readline is currently reading characters defining a keyboard + macro. + + `RL_STATE_OVERWRITE' + Readline is in overwrite mode. + + `RL_STATE_COMPLETING' + Readline is performing word completion. + + `RL_STATE_SIGHANDLER' + Readline is currently executing the readline signal handler. + + `RL_STATE_UNDOING' + Readline is performing an undo. + + `RL_STATE_DONE' + Readline has read a key sequence bound to `accept-line' and + is about to return the line to the caller. + + + - Variable: int rl_explicit_arg + Set to a non-zero value if an explicit numeric argument was + specified by the user. Only valid in a bindable command function. + + - Variable: int rl_numeric_arg + Set to the value of any numeric argument explicitly specified by + the user before executing the current Readline function. Only + valid in a bindable command function. + + - Variable: int rl_editing_mode + Set to a value denoting Readline's current editing mode. A value + of 1 means Readline is currently in emacs mode; 0 means that vi + mode is active. + + +File: readline.info, Node: Readline Convenience Functions, Next: Readline Signal Handling, Prev: Readline Variables, Up: Programming with GNU Readline + +Readline Convenience Functions +============================== + +* Menu: + +* Function Naming:: How to give a function you write a name. +* Keymaps:: Making keymaps. +* Binding Keys:: Changing Keymaps. +* Associating Function Names and Bindings:: Translate function names to + key sequences. +* Allowing Undoing:: How to make your functions undoable. +* Redisplay:: Functions to control line display. +* Modifying Text:: Functions to modify `rl_line_buffer'. +* Character Input:: Functions to read keyboard input. +* Terminal Management:: Functions to manage terminal settings. +* Utility Functions:: Generally useful functions and hooks. +* Miscellaneous Functions:: Functions that don't fall into any category. +* Alternate Interface:: Using Readline in a `callback' fashion. +* A Readline Example:: An example Readline function. + + +File: readline.info, Node: Function Naming, Next: Keymaps, Up: Readline Convenience Functions + +Naming a Function +----------------- + + The user can dynamically change the bindings of keys while using +Readline. This is done by representing the function with a descriptive +name. The user is able to type the descriptive name when referring to +the function. Thus, in an init file, one might find + + Meta-Rubout: backward-kill-word + + This binds the keystroke <Meta-Rubout> to the function +_descriptively_ named `backward-kill-word'. You, as the programmer, +should bind the functions you write to descriptive names as well. +Readline provides a function for doing that: + + - Function: int rl_add_defun (const char *name, rl_command_func_t + *function, int key) + Add NAME to the list of named functions. Make FUNCTION be the + function that gets called. If KEY is not -1, then bind it to + FUNCTION using `rl_bind_key()'. + + Using this function alone is sufficient for most applications. It is +the recommended way to add a few functions to the default functions that +Readline has built in. If you need to do something other than adding a +function to Readline, you may need to use the underlying functions +described below. + + +File: readline.info, Node: Keymaps, Next: Binding Keys, Prev: Function Naming, Up: Readline Convenience Functions + +Selecting a Keymap +------------------ + + Key bindings take place on a "keymap". The keymap is the +association between the keys that the user types and the functions that +get run. You can make your own keymaps, copy existing keymaps, and tell +Readline which keymap to use. + + - Function: Keymap rl_make_bare_keymap (void) + Returns a new, empty keymap. The space for the keymap is + allocated with `malloc()'; the caller should free it by calling + `rl_discard_keymap()' when done. + + - Function: Keymap rl_copy_keymap (Keymap map) + Return a new keymap which is a copy of MAP. + + - Function: Keymap rl_make_keymap (void) + Return a new keymap with the printing characters bound to + rl_insert, the lowercase Meta characters bound to run their + equivalents, and the Meta digits bound to produce numeric + arguments. + + - Function: void rl_discard_keymap (Keymap keymap) + Free the storage associated with KEYMAP. + + Readline has several internal keymaps. These functions allow you to +change which keymap is active. + + - Function: Keymap rl_get_keymap (void) + Returns the currently active keymap. + + - Function: void rl_set_keymap (Keymap keymap) + Makes KEYMAP the currently active keymap. + + - Function: Keymap rl_get_keymap_by_name (const char *name) + Return the keymap matching NAME. NAME is one which would be + supplied in a `set keymap' inputrc line (*note Readline Init + File::). + + - Function: char * rl_get_keymap_name (Keymap keymap) + Return the name matching KEYMAP. NAME is one which would be + supplied in a `set keymap' inputrc line (*note Readline Init + File::). + + +File: readline.info, Node: Binding Keys, Next: Associating Function Names and Bindings, Prev: Keymaps, Up: Readline Convenience Functions + +Binding Keys +------------ + + Key sequences are associate with functions through the keymap. +Readline has several internal keymaps: `emacs_standard_keymap', +`emacs_meta_keymap', `emacs_ctlx_keymap', `vi_movement_keymap', and +`vi_insertion_keymap'. `emacs_standard_keymap' is the default, and the +examples in this manual assume that. + + Since `readline()' installs a set of default key bindings the first +time it is called, there is always the danger that a custom binding +installed before the first call to `readline()' will be overridden. An +alternate mechanism is to install custom key bindings in an +initialization function assigned to the `rl_startup_hook' variable +(*note Readline Variables::). + + These functions manage key bindings. + + - Function: int rl_bind_key (int key, rl_command_func_t *function) + Binds KEY to FUNCTION in the currently active keymap. Returns + non-zero in the case of an invalid KEY. + + - Function: int rl_bind_key_in_map (int key, rl_command_func_t + *function, Keymap map) + Bind KEY to FUNCTION in MAP. Returns non-zero in the case of an + invalid KEY. + + - Function: int rl_unbind_key (int key) + Bind KEY to the null function in the currently active keymap. + Returns non-zero in case of error. + + - Function: int rl_unbind_key_in_map (int key, Keymap map) + Bind KEY to the null function in MAP. Returns non-zero in case of + error. + + - Function: int rl_unbind_function_in_map (rl_command_func_t + *function, Keymap map) + Unbind all keys that execute FUNCTION in MAP. + + - Function: int rl_unbind_command_in_map (const char *command, Keymap + map) + Unbind all keys that are bound to COMMAND in MAP. + + - Function: int rl_set_key (const char *keyseq, rl_command_func_t + *function, Keymap map) + Bind the key sequence represented by the string KEYSEQ to the + function FUNCTION. This makes new keymaps as necessary. The + initial keymap in which to do bindings is MAP. + + - Function: int rl_generic_bind (int type, const char *keyseq, char + *data, Keymap map) + Bind the key sequence represented by the string KEYSEQ to the + arbitrary pointer DATA. TYPE says what kind of data is pointed to + by DATA; this can be a function (`ISFUNC'), a macro (`ISMACR'), or + a keymap (`ISKMAP'). This makes new keymaps as necessary. The + initial keymap in which to do bindings is MAP. + + - Function: int rl_parse_and_bind (char *line) + Parse LINE as if it had been read from the `inputrc' file and + perform any key bindings and variable assignments found (*note + Readline Init File::). + + - Function: int rl_read_init_file (const char *filename) + Read keybindings and variable assignments from FILENAME (*note + Readline Init File::). + + +File: readline.info, Node: Associating Function Names and Bindings, Next: Allowing Undoing, Prev: Binding Keys, Up: Readline Convenience Functions + +Associating Function Names and Bindings +--------------------------------------- + + These functions allow you to find out what keys invoke named +functions and the functions invoked by a particular key sequence. You +may also associate a new function name with an arbitrary function. + + - Function: rl_command_func_t * rl_named_function (const char *name) + Return the function with name NAME. + + - Function: rl_command_func_t * rl_function_of_keyseq (const char + *keyseq, Keymap map, int *type) + Return the function invoked by KEYSEQ in keymap MAP. If MAP is + `NULL', the current keymap is used. If TYPE is not `NULL', the + type of the object is returned in the `int' variable it points to + (one of `ISFUNC', `ISKMAP', or `ISMACR'). + + - Function: char ** rl_invoking_keyseqs (rl_command_func_t *function) + Return an array of strings representing the key sequences used to + invoke FUNCTION in the current keymap. + + - Function: char ** rl_invoking_keyseqs_in_map (rl_command_func_t + *function, Keymap map) + Return an array of strings representing the key sequences used to + invoke FUNCTION in the keymap MAP. + + - Function: void rl_function_dumper (int readable) + Print the readline function names and the key sequences currently + bound to them to `rl_outstream'. If READABLE is non-zero, the + list is formatted in such a way that it can be made part of an + `inputrc' file and re-read. + + - Function: void rl_list_funmap_names (void) + Print the names of all bindable Readline functions to + `rl_outstream'. + + - Function: const char ** rl_funmap_names (void) + Return a NULL terminated array of known function names. The array + is sorted. The array itself is allocated, but not the strings + inside. You should `free()' the array when you are done, but not + the pointers. + + - Function: int rl_add_funmap_entry (const char *name, + rl_command_func_t *function) + Add NAME to the list of bindable Readline command names, and make + FUNCTION the function to be called when NAME is invoked. + + +File: readline.info, Node: Allowing Undoing, Next: Redisplay, Prev: Associating Function Names and Bindings, Up: Readline Convenience Functions + +Allowing Undoing +---------------- + + Supporting the undo command is a painless thing, and makes your +functions much more useful. It is certainly easy to try something if +you know you can undo it. + + If your function simply inserts text once, or deletes text once, and +uses `rl_insert_text()' or `rl_delete_text()' to do it, then undoing is +already done for you automatically. + + If you do multiple insertions or multiple deletions, or any +combination of these operations, you should group them together into +one operation. This is done with `rl_begin_undo_group()' and +`rl_end_undo_group()'. + + The types of events that can be undone are: + + enum undo_code { UNDO_DELETE, UNDO_INSERT, UNDO_BEGIN, UNDO_END }; + + Notice that `UNDO_DELETE' means to insert some text, and +`UNDO_INSERT' means to delete some text. That is, the undo code tells +what to undo, not how to undo it. `UNDO_BEGIN' and `UNDO_END' are tags +added by `rl_begin_undo_group()' and `rl_end_undo_group()'. + + - Function: int rl_begin_undo_group (void) + Begins saving undo information in a group construct. The undo + information usually comes from calls to `rl_insert_text()' and + `rl_delete_text()', but could be the result of calls to + `rl_add_undo()'. + + - Function: int rl_end_undo_group (void) + Closes the current undo group started with `rl_begin_undo_group + ()'. There should be one call to `rl_end_undo_group()' for each + call to `rl_begin_undo_group()'. + + - Function: void rl_add_undo (enum undo_code what, int start, int end, + char *text) + Remember how to undo an event (according to WHAT). The affected + text runs from START to END, and encompasses TEXT. + + - Function: void rl_free_undo_list (void) + Free the existing undo list. + + - Function: int rl_do_undo (void) + Undo the first thing on the undo list. Returns `0' if there was + nothing to undo, non-zero if something was undone. + + Finally, if you neither insert nor delete text, but directly modify +the existing text (e.g., change its case), call `rl_modifying()' once, +just before you modify the text. You must supply the indices of the +text range that you are going to modify. + + - Function: int rl_modifying (int start, int end) + Tell Readline to save the text between START and END as a single + undo unit. It is assumed that you will subsequently modify that + text. + + +File: readline.info, Node: Redisplay, Next: Modifying Text, Prev: Allowing Undoing, Up: Readline Convenience Functions + +Redisplay +--------- + + - Function: void rl_redisplay (void) + Change what's displayed on the screen to reflect the current + contents of `rl_line_buffer'. + + - Function: int rl_forced_update_display (void) + Force the line to be updated and redisplayed, whether or not + Readline thinks the screen display is correct. + + - Function: int rl_on_new_line (void) + Tell the update functions that we have moved onto a new (empty) + line, usually after ouputting a newline. + + - Function: int rl_on_new_line_with_prompt (void) + Tell the update functions that we have moved onto a new line, with + RL_PROMPT already displayed. This could be used by applications + that want to output the prompt string themselves, but still need + Readline to know the prompt string length for redisplay. It + should be used after setting RL_ALREADY_PROMPTED. + + - Function: int rl_reset_line_state (void) + Reset the display state to a clean state and redisplay the current + line starting on a new line. + + - Function: int rl_crlf (void) + Move the cursor to the start of the next screen line. + + - Function: int rl_show_char (int c) + Display character C on `rl_outstream'. If Readline has not been + set to display meta characters directly, this will convert meta + characters to a meta-prefixed key sequence. This is intended for + use by applications which wish to do their own redisplay. + + - Function: int rl_message (const char *, ...) + The arguments are a format string as would be supplied to `printf', + possibly containing conversion specifications such as `%d', and + any additional arguments necessary to satisfy the conversion + specifications. The resulting string is displayed in the "echo + area". The echo area is also used to display numeric arguments + and search strings. + + - Function: int rl_clear_message (void) + Clear the message in the echo area. + + - Function: void rl_save_prompt (void) + Save the local Readline prompt display state in preparation for + displaying a new message in the message area with `rl_message()'. + + - Function: void rl_restore_prompt (void) + Restore the local Readline prompt display state saved by the most + recent call to `rl_save_prompt'. + + - Function: int rl_expand_prompt (char *prompt) + Expand any special character sequences in PROMPT and set up the + local Readline prompt redisplay variables. This function is + called by `readline()'. It may also be called to expand the + primary prompt if the `rl_on_new_line_with_prompt()' function or + `rl_already_prompted' variable is used. It returns the number of + visible characters on the last line of the (possibly multi-line) + prompt. + + - Function: int rl_set_prompt (const char *prompt) + Make Readline use PROMPT for subsequent redisplay. This calls + `rl_expand_prompt()' to expand the prompt and sets `rl_prompt' to + the result. + + +File: readline.info, Node: Modifying Text, Next: Character Input, Prev: Redisplay, Up: Readline Convenience Functions + +Modifying Text +-------------- + + - Function: int rl_insert_text (const char *text) + Insert TEXT into the line at the current cursor position. Returns + the number of characters inserted. + + - Function: int rl_delete_text (int start, int end) + Delete the text between START and END in the current line. + Returns the number of characters deleted. + + - Function: char * rl_copy_text (int start, int end) + Return a copy of the text between START and END in the current + line. + + - Function: int rl_kill_text (int start, int end) + Copy the text between START and END in the current line to the + kill ring, appending or prepending to the last kill if the last + command was a kill command. The text is deleted. If START is + less than END, the text is appended, otherwise prepended. If the + last command was not a kill, a new kill ring slot is used. + + - Function: int rl_push_macro_input (char *macro) + Cause MACRO to be inserted into the line, as if it had been invoked + by a key bound to a macro. Not especially useful; use + `rl_insert_text()' instead. + + +File: readline.info, Node: Character Input, Next: Terminal Management, Prev: Modifying Text, Up: Readline Convenience Functions + +Character Input +--------------- + + - Function: int rl_read_key (void) + Return the next character available from Readline's current input + stream. This handles input inserted into the input stream via + RL_PENDING_INPUT (*note Readline Variables::) and + `rl_stuff_char()', macros, and characters read from the keyboard. + While waiting for input, this function will call any function + assigned to the `rl_event_hook' variable. + + - Function: int rl_getc (FILE *stream) + Return the next character available from STREAM, which is assumed + to be the keyboard. + + - Function: int rl_stuff_char (int c) + Insert C into the Readline input stream. It will be "read" before + Readline attempts to read characters from the terminal with + `rl_read_key()'. Up to 512 characters may be pushed back. + `rl_stuff_char' returns 1 if the character was successfully + inserted; 0 otherwise. + + - Function: int rl_execute_next (int c) + Make C be the next command to be executed when `rl_read_key()' is + called. This sets RL_PENDING_INPUT. + + - Function: int rl_clear_pending_input (void) + Unset RL_PENDING_INPUT, effectively negating the effect of any + previous call to `rl_execute_next()'. This works only if the + pending input has not already been read with `rl_read_key()'. + + - Function: int rl_set_keyboard_input_timeout (int u) + While waiting for keyboard input in `rl_read_key()', Readline will + wait for U microseconds for input before calling any function + assigned to `rl_event_hook'. The default waiting period is + one-tenth of a second. Returns the old timeout value. + + +File: readline.info, Node: Terminal Management, Next: Utility Functions, Prev: Character Input, Up: Readline Convenience Functions + +Terminal Management +------------------- + + - Function: void rl_prep_terminal (int meta_flag) + Modify the terminal settings for Readline's use, so `readline()' + can read a single character at a time from the keyboard. The + META_FLAG argument should be non-zero if Readline should read + eight-bit input. + + - Function: void rl_deprep_terminal (void) + Undo the effects of `rl_prep_terminal()', leaving the terminal in + the state in which it was before the most recent call to + `rl_prep_terminal()'. + + - Function: void rl_tty_set_default_bindings (Keymap kmap) + Read the operating system's terminal editing characters (as would + be displayed by `stty') to their Readline equivalents. The + bindings are performed in KMAP. + + - Function: int rl_reset_terminal (const char *terminal_name) + Reinitialize Readline's idea of the terminal settings using + TERMINAL_NAME as the terminal type (e.g., `vt100'). If + TERMINAL_NAME is `NULL', the value of the `TERM' environment + variable is used. + + +File: readline.info, Node: Utility Functions, Next: Miscellaneous Functions, Prev: Terminal Management, Up: Readline Convenience Functions + +Utility Functions +----------------- + + - Function: void rl_replace_line (const char *text, int clear_undo) + Replace the contents of `rl_line_buffer' with TEXT. The point and + mark are preserved, if possible. If CLEAR_UNDO is non-zero, the + undo list associated with the current line is cleared. + + - Function: int rl_extend_line_buffer (int len) + Ensure that `rl_line_buffer' has enough space to hold LEN + characters, possibly reallocating it if necessary. + + - Function: int rl_initialize (void) + Initialize or re-initialize Readline's internal state. It's not + strictly necessary to call this; `readline()' calls it before + reading any input. + + - Function: int rl_ding (void) + Ring the terminal bell, obeying the setting of `bell-style'. + + - Function: int rl_alphabetic (int c) + Return 1 if C is an alphabetic character. + + - Function: void rl_display_match_list (char **matches, int len, int + max) + A convenience function for displaying a list of strings in + columnar format on Readline's output stream. `matches' is the list + of strings, in argv format, such as a list of completion matches. + `len' is the number of strings in `matches', and `max' is the + length of the longest string in `matches'. This function uses the + setting of `print-completions-horizontally' to select how the + matches are displayed (*note Readline Init File Syntax::). + + The following are implemented as macros, defined in `chardefs.h'. +Applications should refrain from using them. + + - Function: int _rl_uppercase_p (int c) + Return 1 if C is an uppercase alphabetic character. + + - Function: int _rl_lowercase_p (int c) + Return 1 if C is a lowercase alphabetic character. + + - Function: int _rl_digit_p (int c) + Return 1 if C is a numeric character. + + - Function: int _rl_to_upper (int c) + If C is a lowercase alphabetic character, return the corresponding + uppercase character. + + - Function: int _rl_to_lower (int c) + If C is an uppercase alphabetic character, return the corresponding + lowercase character. + + - Function: int _rl_digit_value (int c) + If C is a number, return the value it represents. + + +File: readline.info, Node: Miscellaneous Functions, Next: Alternate Interface, Prev: Utility Functions, Up: Readline Convenience Functions + +Miscellaneous Functions +----------------------- + + - Function: int rl_macro_bind (const char *keyseq, const char *macro, + Keymap map) + Bind the key sequence KEYSEQ to invoke the macro MACRO. The + binding is performed in MAP. When KEYSEQ is invoked, the MACRO + will be inserted into the line. This function is deprecated; use + `rl_generic_bind()' instead. + + - Function: void rl_macro_dumper (int readable) + Print the key sequences bound to macros and their values, using + the current keymap, to `rl_outstream'. If READABLE is non-zero, + the list is formatted in such a way that it can be made part of an + `inputrc' file and re-read. + + - Function: int rl_variable_bind (const char *variable, const char + *value) + Make the Readline variable VARIABLE have VALUE. This behaves as + if the readline command `set VARIABLE VALUE' had been executed in + an `inputrc' file (*note Readline Init File Syntax::). + + - Function: void rl_variable_dumper (int readable) + Print the readline variable names and their current values to + `rl_outstream'. If READABLE is non-zero, the list is formatted in + such a way that it can be made part of an `inputrc' file and + re-read. + + - Function: int rl_set_paren_blink_timeout (int u) + Set the time interval (in microseconds) that Readline waits when + showing a balancing character when `blink-matching-paren' has been + enabled. + + - Function: char * rl_get_termcap (const char *cap) + Retrieve the string value of the termcap capability CAP. Readline + fetches the termcap entry for the current terminal name and uses + those capabilities to move around the screen line and perform other + terminal-specific operations, like erasing a line. Readline does + not use all of a terminal's capabilities, and this function will + return values for only those capabilities Readline uses. + + +File: readline.info, Node: Alternate Interface, Next: A Readline Example, Prev: Miscellaneous Functions, Up: Readline Convenience Functions + +Alternate Interface +------------------- + + An alternate interface is available to plain `readline()'. Some +applications need to interleave keyboard I/O with file, device, or +window system I/O, typically by using a main loop to `select()' on +various file descriptors. To accomodate this need, readline can also +be invoked as a `callback' function from an event loop. There are +functions available to make this easy. + + - Function: void rl_callback_handler_install (const char *prompt, + rl_vcpfunc_t *lhandler) + Set up the terminal for readline I/O and display the initial + expanded value of PROMPT. Save the value of LHANDLER to use as a + function to call when a complete line of input has been entered. + The function takes the text of the line as an argument. + + - Function: void rl_callback_read_char (void) + Whenever an application determines that keyboard input is + available, it should call `rl_callback_read_char()', which will + read the next character from the current input source. If that + character completes the line, `rl_callback_read_char' will invoke + the LHANDLER function saved by `rl_callback_handler_install' to + process the line. Before calling the LHANDLER function, the + terminal settings are reset to the values they had before calling + `rl_callback_handler_install'. If the LHANDLER function returns, + the terminal settings are modified for Readline's use again. + `EOF' is indicated by calling LHANDLER with a `NULL' line. + + - Function: void rl_callback_handler_remove (void) + Restore the terminal to its initial state and remove the line + handler. This may be called from within a callback as well as + independently. If the LHANDLER installed by + `rl_callback_handler_install' does not exit the program, either + this function or the function referred to by the value of + `rl_deprep_term_function' should be called before the program + exits to reset the terminal settings. + + +File: readline.info, Node: A Readline Example, Prev: Alternate Interface, Up: Readline Convenience Functions + +A Readline Example +------------------ + + Here is a function which changes lowercase characters to their +uppercase equivalents, and uppercase characters to lowercase. If this +function was bound to `M-c', then typing `M-c' would change the case of +the character under point. Typing `M-1 0 M-c' would change the case of +the following 10 characters, leaving the cursor on the last character +changed. + + /* Invert the case of the COUNT following characters. */ + int + invert_case_line (count, key) + int count, key; + { + register int start, end, i; + + start = rl_point; + + if (rl_point >= rl_end) + return (0); + + if (count < 0) + { + direction = -1; + count = -count; + } + else + direction = 1; + + /* Find the end of the range to modify. */ + end = start + (count * direction); + + /* Force it to be within range. */ + if (end > rl_end) + end = rl_end; + else if (end < 0) + end = 0; + + if (start == end) + return (0); + + if (start > end) + { + int temp = start; + start = end; + end = temp; + } + + /* Tell readline that we are modifying the line, + so it will save the undo information. */ + rl_modifying (start, end); + + for (i = start; i != end; i++) + { + if (_rl_uppercase_p (rl_line_buffer[i])) + rl_line_buffer[i] = _rl_to_lower (rl_line_buffer[i]); + else if (_rl_lowercase_p (rl_line_buffer[i])) + rl_line_buffer[i] = _rl_to_upper (rl_line_buffer[i]); + } + /* Move point to on top of the last character changed. */ + rl_point = (direction == 1) ? end - 1 : start; + return (0); + } + + +File: readline.info, Node: Readline Signal Handling, Next: Custom Completers, Prev: Readline Convenience Functions, Up: Programming with GNU Readline + +Readline Signal Handling +======================== + + Signals are asynchronous events sent to a process by the Unix kernel, +sometimes on behalf of another process. They are intended to indicate +exceptional events, like a user pressing the interrupt key on his +terminal, or a network connection being broken. There is a class of +signals that can be sent to the process currently reading input from +the keyboard. Since Readline changes the terminal attributes when it +is called, it needs to perform special processing when such a signal is +received in order to restore the terminal to a sane state, or provide +application writers with functions to do so manually. + + Readline contains an internal signal handler that is installed for a +number of signals (`SIGINT', `SIGQUIT', `SIGTERM', `SIGALRM', +`SIGTSTP', `SIGTTIN', and `SIGTTOU'). When one of these signals is +received, the signal handler will reset the terminal attributes to +those that were in effect before `readline()' was called, reset the +signal handling to what it was before `readline()' was called, and +resend the signal to the calling application. If and when the calling +application's signal handler returns, Readline will reinitialize the +terminal and continue to accept input. When a `SIGINT' is received, +the Readline signal handler performs some additional work, which will +cause any partially-entered line to be aborted (see the description of +`rl_free_line_state()' below). + + There is an additional Readline signal handler, for `SIGWINCH', which +the kernel sends to a process whenever the terminal's size changes (for +example, if a user resizes an `xterm'). The Readline `SIGWINCH' +handler updates Readline's internal screen size information, and then +calls any `SIGWINCH' signal handler the calling application has +installed. Readline calls the application's `SIGWINCH' signal handler +without resetting the terminal to its original state. If the +application's signal handler does more than update its idea of the +terminal size and return (for example, a `longjmp' back to a main +processing loop), it _must_ call `rl_cleanup_after_signal()' (described +below), to restore the terminal state. + + Readline provides two variables that allow application writers to +control whether or not it will catch certain signals and act on them +when they are received. It is important that applications change the +values of these variables only when calling `readline()', not in a +signal handler, so Readline's internal signal state is not corrupted. + + - Variable: int rl_catch_signals + If this variable is non-zero, Readline will install signal + handlers for `SIGINT', `SIGQUIT', `SIGTERM', `SIGALRM', `SIGTSTP', + `SIGTTIN', and `SIGTTOU'. + + The default value of `rl_catch_signals' is 1. + + - Variable: int rl_catch_sigwinch + If this variable is non-zero, Readline will install a signal + handler for `SIGWINCH'. + + The default value of `rl_catch_sigwinch' is 1. + + If an application does not wish to have Readline catch any signals, +or to handle signals other than those Readline catches (`SIGHUP', for +example), Readline provides convenience functions to do the necessary +terminal and internal state cleanup upon receipt of a signal. + + - Function: void rl_cleanup_after_signal (void) + This function will reset the state of the terminal to what it was + before `readline()' was called, and remove the Readline signal + handlers for all signals, depending on the values of + `rl_catch_signals' and `rl_catch_sigwinch'. + + - Function: void rl_free_line_state (void) + This will free any partial state associated with the current input + line (undo information, any partial history entry, any + partially-entered keyboard macro, and any partially-entered + numeric argument). This should be called before + `rl_cleanup_after_signal()'. The Readline signal handler for + `SIGINT' calls this to abort the current input line. + + - Function: void rl_reset_after_signal (void) + This will reinitialize the terminal and reinstall any Readline + signal handlers, depending on the values of `rl_catch_signals' and + `rl_catch_sigwinch'. + + If an application does not wish Readline to catch `SIGWINCH', it may +call `rl_resize_terminal()' or `rl_set_screen_size()' to force Readline +to update its idea of the terminal size when a `SIGWINCH' is received. + + - Function: void rl_resize_terminal (void) + Update Readline's internal screen size by reading values from the + kernel. + + - Function: void rl_set_screen_size (int rows, int cols) + Set Readline's idea of the terminal size to ROWS rows and COLS + columns. + + If an application does not want to install a `SIGWINCH' handler, but +is still interested in the screen dimensions, Readline's idea of the +screen size may be queried. + + - Function: void rl_get_screen_size (int *rows, int *cols) + Return Readline's idea of the terminal's size in the variables + pointed to by the arguments. + + The following functions install and remove Readline's signal +handlers. + + - Function: int rl_set_signals (void) + Install Readline's signal handler for `SIGINT', `SIGQUIT', + `SIGTERM', `SIGALRM', `SIGTSTP', `SIGTTIN', `SIGTTOU', and + `SIGWINCH', depending on the values of `rl_catch_signals' and + `rl_catch_sigwinch'. + + - Function: int rl_clear_signals (void) + Remove all of the Readline signal handlers installed by + `rl_set_signals()'. + + +File: readline.info, Node: Custom Completers, Prev: Readline Signal Handling, Up: Programming with GNU Readline + +Custom Completers +================= + + Typically, a program that reads commands from the user has a way of +disambiguating commands and data. If your program is one of these, then +it can provide completion for commands, data, or both. The following +sections describe how your program and Readline cooperate to provide +this service. + +* Menu: + +* How Completing Works:: The logic used to do completion. +* Completion Functions:: Functions provided by Readline. +* Completion Variables:: Variables which control completion. +* A Short Completion Example:: An example of writing completer subroutines. + + +File: readline.info, Node: How Completing Works, Next: Completion Functions, Up: Custom Completers + +How Completing Works +-------------------- + + In order to complete some text, the full list of possible completions +must be available. That is, it is not possible to accurately expand a +partial word without knowing all of the possible words which make sense +in that context. The Readline library provides the user interface to +completion, and two of the most common completion functions: filename +and username. For completing other types of text, you must write your +own completion function. This section describes exactly what such +functions must do, and provides an example. + + There are three major functions used to perform completion: + + 1. The user-interface function `rl_complete()'. This function is + called with the same arguments as other bindable Readline + functions: COUNT and INVOKING_KEY. It isolates the word to be + completed and calls `rl_completion_matches()' to generate a list + of possible completions. It then either lists the possible + completions, inserts the possible completions, or actually + performs the completion, depending on which behavior is desired. + + 2. The internal function `rl_completion_matches()' uses an + application-supplied "generator" function to generate the list of + possible matches, and then returns the array of these matches. + The caller should place the address of its generator function in + `rl_completion_entry_function'. + + 3. The generator function is called repeatedly from + `rl_completion_matches()', returning a string each time. The + arguments to the generator function are TEXT and STATE. TEXT is + the partial word to be completed. STATE is zero the first time + the function is called, allowing the generator to perform any + necessary initialization, and a positive non-zero integer for each + subsequent call. The generator function returns `(char *)NULL' to + inform `rl_completion_matches()' that there are no more + possibilities left. Usually the generator function computes the + list of possible completions when STATE is zero, and returns them + one at a time on subsequent calls. Each string the generator + function returns as a match must be allocated with `malloc()'; + Readline frees the strings when it has finished with them. + + + - Function: int rl_complete (int ignore, int invoking_key) + Complete the word at or before point. You have supplied the + function that does the initial simple matching selection algorithm + (see `rl_completion_matches()'). The default is to do filename + completion. + + - Variable: rl_compentry_func_t * rl_completion_entry_function + This is a pointer to the generator function for + `rl_completion_matches()'. If the value of + `rl_completion_entry_function' is `NULL' then the default filename + generator function, `rl_filename_completion_function()', is used. + + +File: readline.info, Node: Completion Functions, Next: Completion Variables, Prev: How Completing Works, Up: Custom Completers + +Completion Functions +-------------------- + + Here is the complete list of callable completion functions present in +Readline. + + - Function: int rl_complete_internal (int what_to_do) + Complete the word at or before point. WHAT_TO_DO says what to do + with the completion. A value of `?' means list the possible + completions. `TAB' means do standard completion. `*' means + insert all of the possible completions. `!' means to display all + of the possible completions, if there is more than one, as well as + performing partial completion. + + - Function: int rl_complete (int ignore, int invoking_key) + Complete the word at or before point. You have supplied the + function that does the initial simple matching selection algorithm + (see `rl_completion_matches()' and `rl_completion_entry_function'). + The default is to do filename completion. This calls + `rl_complete_internal()' with an argument depending on + INVOKING_KEY. + + - Function: int rl_possible_completions (int count, int invoking_key) + List the possible completions. See description of `rl_complete + ()'. This calls `rl_complete_internal()' with an argument of `?'. + + - Function: int rl_insert_completions (int count, int invoking_key) + Insert the list of possible completions into the line, deleting the + partially-completed word. See description of `rl_complete()'. + This calls `rl_complete_internal()' with an argument of `*'. + + - Function: int rl_completion_mode (rl_command_func_t *cfunc) + Returns the apppriate value to pass to `rl_complete_internal()' + depending on whether CFUNC was called twice in succession and the + value of the `show-all-if-ambiguous' variable. + Application-specific completion functions may use this function to + present the same interface as `rl_complete()'. + + - Function: char ** rl_completion_matches (const char *text, + rl_compentry_func_t *entry_func) + Returns an array of strings which is a list of completions for + TEXT. If there are no completions, returns `NULL'. The first + entry in the returned array is the substitution for TEXT. The + remaining entries are the possible completions. The array is + terminated with a `NULL' pointer. + + ENTRY_FUNC is a function of two args, and returns a `char *'. The + first argument is TEXT. The second is a state argument; it is + zero on the first call, and non-zero on subsequent calls. + ENTRY_FUNC returns a `NULL' pointer to the caller when there are + no more matches. + + - Function: char * rl_filename_completion_function (const char *text, + int state) + A generator function for filename completion in the general case. + TEXT is a partial filename. The Bash source is a useful reference + for writing custom completion functions (the Bash completion + functions call this and other Readline functions). + + - Function: char * rl_username_completion_function (const char *text, + int state) + A completion generator for usernames. TEXT contains a partial + username preceded by a random character (usually `~'). As with all + completion generators, STATE is zero on the first call and non-zero + for subsequent calls. + + +File: readline.info, Node: Completion Variables, Next: A Short Completion Example, Prev: Completion Functions, Up: Custom Completers + +Completion Variables +-------------------- + + - Variable: rl_compentry_func_t * rl_completion_entry_function + A pointer to the generator function for `rl_completion_matches()'. + `NULL' means to use `rl_filename_completion_function()', the + default filename completer. + + - Variable: rl_completion_func_t * rl_attempted_completion_function + A pointer to an alternative function to create matches. The + function is called with TEXT, START, and END. START and END are + indices in `rl_line_buffer' defining the boundaries of TEXT, which + is a character string. If this function exists and returns + `NULL', or if this variable is set to `NULL', then `rl_complete()' + will call the value of `rl_completion_entry_function' to generate + matches, otherwise the array of strings returned will be used. If + this function sets the `rl_attempted_completion_over' variable to + a non-zero value, Readline will not perform its default completion + even if this function returns no matches. + + - Variable: rl_quote_func_t * rl_filename_quoting_function + A pointer to a function that will quote a filename in an + application-specific fashion. This is called if filename + completion is being attempted and one of the characters in + `rl_filename_quote_characters' appears in a completed filename. + The function is called with TEXT, MATCH_TYPE, and QUOTE_POINTER. + The TEXT is the filename to be quoted. The MATCH_TYPE is either + `SINGLE_MATCH', if there is only one completion match, or + `MULT_MATCH'. Some functions use this to decide whether or not to + insert a closing quote character. The QUOTE_POINTER is a pointer + to any opening quote character the user typed. Some functions + choose to reset this character. + + - Variable: rl_dequote_func_t * rl_filename_dequoting_function + A pointer to a function that will remove application-specific + quoting characters from a filename before completion is attempted, + so those characters do not interfere with matching the text + against names in the filesystem. It is called with TEXT, the text + of the word to be dequoted, and QUOTE_CHAR, which is the quoting + character that delimits the filename (usually `'' or `"'). If + QUOTE_CHAR is zero, the filename was not in an embedded string. + + - Variable: rl_linebuf_func_t * rl_char_is_quoted_p + A pointer to a function to call that determines whether or not a + specific character in the line buffer is quoted, according to + whatever quoting mechanism the program calling Readline uses. The + function is called with two arguments: TEXT, the text of the line, + and INDEX, the index of the character in the line. It is used to + decide whether a character found in + `rl_completer_word_break_characters' should be used to break words + for the completer. + + - Variable: rl_compignore_func_t * rl_ignore_some_completions_function + This function, if defined, is called by the completer when real + filename completion is done, after all the matching names have + been generated. It is passed a `NULL' terminated array of matches. + The first element (`matches[0]') is the maximal substring common + to all matches. This function can re-arrange the list of matches + as required, but each element deleted from the array must be freed. + + - Variable: rl_icppfunc_t * rl_directory_completion_hook + This function, if defined, is allowed to modify the directory + portion of filenames Readline completes. It is called with the + address of a string (the current directory name) as an argument, + and may modify that string. If the string is replaced with a new + string, the old value should be freed. Any modified directory + name should have a trailing slash. The modified value will be + displayed as part of the completion, replacing the directory + portion of the pathname the user typed. It returns an integer + that should be non-zero if the function modifies its directory + argument. It could be used to expand symbolic links or shell + variables in pathnames. + + - Variable: rl_compdisp_func_t * rl_completion_display_matches_hook + If non-zero, then this is the address of a function to call when + completing a word would normally display the list of possible + matches. This function is called in lieu of Readline displaying + the list. It takes three arguments: (`char **'MATCHES, `int' + NUM_MATCHES, `int' MAX_LENGTH) where MATCHES is the array of + matching strings, NUM_MATCHES is the number of strings in that + array, and MAX_LENGTH is the length of the longest string in that + array. Readline provides a convenience function, + `rl_display_match_list', that takes care of doing the display to + Readline's output stream. That function may be called from this + hook. + + - Variable: const char * rl_basic_word_break_characters + The basic list of characters that signal a break between words for + the completer routine. The default value of this variable is the + characters which break words for completion in Bash: `" + \t\n\"\\'`@$><=;|&{("'. + + - Variable: const char * rl_basic_quote_characters + A list of quote characters which can cause a word break. + + - Variable: const char * rl_completer_word_break_characters + The list of characters that signal a break between words for + `rl_complete_internal()'. The default list is the value of + `rl_basic_word_break_characters'. + + - Variable: const char * rl_completer_quote_characters + A list of characters which can be used to quote a substring of the + line. Completion occurs on the entire substring, and within the + substring `rl_completer_word_break_characters' are treated as any + other character, unless they also appear within this list. + + - Variable: const char * rl_filename_quote_characters + A list of characters that cause a filename to be quoted by the + completer when they appear in a completed filename. The default + is the null string. + + - Variable: const char * rl_special_prefixes + The list of characters that are word break characters, but should + be left in TEXT when it is passed to the completion function. + Programs can use this to help determine what kind of completing to + do. For instance, Bash sets this variable to "$@" so that it can + complete shell variables and hostnames. + + - Variable: int rl_completion_query_items + Up to this many items will be displayed in response to a + possible-completions call. After that, we ask the user if she is + sure she wants to see them all. The default value is 100. + + - Variable: int rl_completion_append_character + When a single completion alternative matches at the end of the + command line, this character is appended to the inserted + completion text. The default is a space character (` '). Setting + this to the null character (`\0') prevents anything being appended + automatically. This can be changed in custom completion functions + to provide the "most sensible word separator character" according + to an application-specific command line syntax specification. + + - Variable: int rl_completion_suppress_append + If non-zero, RL_COMPLETION_APPEND_CHARACTER is not appended to + matches at the end of the command line, as described above. It is + set to 0 before any application-specific completion function is + called. + + - Variable: int rl_completion_mark_symlink_dirs + If non-zero, a slash will be appended to completed filenames that + are symbolic links to directory names, subject to the value of the + user-settable MARK-DIRECTORIES variable. This variable exists so + that application completion functions can override the user's + global preference (set via the MARK-SYMLINKED-DIRECTORIES Readline + variable) if appropriate. This variable is set to the user's + preference before any application completion function is called, + so unless that function modifies the value, the user's preferences + are honored. + + - Variable: int rl_ignore_completion_duplicates + If non-zero, then duplicates in the matches are removed. The + default is 1. + + - Variable: int rl_filename_completion_desired + Non-zero means that the results of the matches are to be treated as + filenames. This is _always_ zero on entry, and can only be changed + within a completion entry generator function. If it is set to a + non-zero value, directory names have a slash appended and Readline + attempts to quote completed filenames if they contain any + characters in `rl_filename_quote_characters' and + `rl_filename_quoting_desired' is set to a non-zero value. + + - Variable: int rl_filename_quoting_desired + Non-zero means that the results of the matches are to be quoted + using double quotes (or an application-specific quoting mechanism) + if the completed filename contains any characters in + `rl_filename_quote_chars'. This is _always_ non-zero on entry, + and can only be changed within a completion entry generator + function. The quoting is effected via a call to the function + pointed to by `rl_filename_quoting_function'. + + - Variable: int rl_attempted_completion_over + If an application-specific completion function assigned to + `rl_attempted_completion_function' sets this variable to a non-zero + value, Readline will not perform its default filename completion + even if the application's completion function returns no matches. + It should be set only by an application's completion function. + + - Variable: int rl_completion_type + Set to a character describing the type of completion Readline is + currently attempting; see the description of + `rl_complete_internal()' (*note Completion Functions::) for the + list of characters. + + - Variable: int rl_inhibit_completion + If this variable is non-zero, completion is inhibited. The + completion character will be inserted as any other bound to + `self-insert'. + + +File: readline.info, Node: A Short Completion Example, Prev: Completion Variables, Up: Custom Completers + +A Short Completion Example +-------------------------- + + Here is a small application demonstrating the use of the GNU Readline +library. It is called `fileman', and the source code resides in +`examples/fileman.c'. This sample application provides completion of +command names, line editing features, and access to the history list. + + /* fileman.c -- A tiny application which demonstrates how to use the + GNU Readline library. This application interactively allows users + to manipulate files and their modes. */ + + #include <stdio.h> + #include <sys/types.h> + #include <sys/file.h> + #include <sys/stat.h> + #include <sys/errno.h> + + #include <readline/readline.h> + #include <readline/history.h> + + extern char *xmalloc (); + + /* The names of functions that actually do the manipulation. */ + int com_list __P((char *)); + int com_view __P((char *)); + int com_rename __P((char *)); + int com_stat __P((char *)); + int com_pwd __P((char *)); + int com_delete __P((char *)); + int com_help __P((char *)); + int com_cd __P((char *)); + int com_quit __P((char *)); + + /* A structure which contains information on the commands this program + can understand. */ + + typedef struct { + char *name; /* User printable name of the function. */ + rl_icpfunc_t *func; /* Function to call to do the job. */ + char *doc; /* Documentation for this function. */ + } COMMAND; + + COMMAND commands[] = { + { "cd", com_cd, "Change to directory DIR" }, + { "delete", com_delete, "Delete FILE" }, + { "help", com_help, "Display this text" }, + { "?", com_help, "Synonym for `help'" }, + { "list", com_list, "List files in DIR" }, + { "ls", com_list, "Synonym for `list'" }, + { "pwd", com_pwd, "Print the current working directory" }, + { "quit", com_quit, "Quit using Fileman" }, + { "rename", com_rename, "Rename FILE to NEWNAME" }, + { "stat", com_stat, "Print out statistics on FILE" }, + { "view", com_view, "View the contents of FILE" }, + { (char *)NULL, (rl_icpfunc_t *)NULL, (char *)NULL } + }; + + /* Forward declarations. */ + char *stripwhite (); + COMMAND *find_command (); + + /* The name of this program, as taken from argv[0]. */ + char *progname; + + /* When non-zero, this means the user is done using this program. */ + int done; + + char * + dupstr (s) + int s; + { + char *r; + + r = xmalloc (strlen (s) + 1); + strcpy (r, s); + return (r); + } + + main (argc, argv) + int argc; + char **argv; + { + char *line, *s; + + progname = argv[0]; + + initialize_readline (); /* Bind our completer. */ + + /* Loop reading and executing lines until the user quits. */ + for ( ; done == 0; ) + { + line = readline ("FileMan: "); + + if (!line) + break; + + /* Remove leading and trailing whitespace from the line. + Then, if there is anything left, add it to the history list + and execute it. */ + s = stripwhite (line); + + if (*s) + { + add_history (s); + execute_line (s); + } + + free (line); + } + exit (0); + } + + /* Execute a command line. */ + int + execute_line (line) + char *line; + { + register int i; + COMMAND *command; + char *word; + + /* Isolate the command word. */ + i = 0; + while (line[i] && whitespace (line[i])) + i++; + word = line + i; + + while (line[i] && !whitespace (line[i])) + i++; + + if (line[i]) + line[i++] = '\0'; + + command = find_command (word); + + if (!command) + { + fprintf (stderr, "%s: No such command for FileMan.\n", word); + return (-1); + } + + /* Get argument to command, if any. */ + while (whitespace (line[i])) + i++; + + word = line + i; + + /* Call the function. */ + return ((*(command->func)) (word)); + } + + /* Look up NAME as the name of a command, and return a pointer to that + command. Return a NULL pointer if NAME isn't a command name. */ + COMMAND * + find_command (name) + char *name; + { + register int i; + + for (i = 0; commands[i].name; i++) + if (strcmp (name, commands[i].name) == 0) + return (&commands[i]); + + return ((COMMAND *)NULL); + } + + /* Strip whitespace from the start and end of STRING. Return a pointer + into STRING. */ + char * + stripwhite (string) + char *string; + { + register char *s, *t; + + for (s = string; whitespace (*s); s++) + ; + + if (*s == 0) + return (s); + + t = s + strlen (s) - 1; + while (t > s && whitespace (*t)) + t--; + *++t = '\0'; + + return s; + } + + /* **************************************************************** */ + /* */ + /* Interface to Readline Completion */ + /* */ + /* **************************************************************** */ + + char *command_generator __P((const char *, int)); + char **fileman_completion __P((const char *, int, int)); + + /* Tell the GNU Readline library how to complete. We want to try to + complete on command names if this is the first word in the line, or + on filenames if not. */ + initialize_readline () + { + /* Allow conditional parsing of the ~/.inputrc file. */ + rl_readline_name = "FileMan"; + + /* Tell the completer that we want a crack first. */ + rl_attempted_completion_function = fileman_completion; + } + + /* Attempt to complete on the contents of TEXT. START and END + bound the region of rl_line_buffer that contains the word to + complete. TEXT is the word to complete. We can use the entire + contents of rl_line_buffer in case we want to do some simple + parsing. Returnthe array of matches, or NULL if there aren't any. */ + char ** + fileman_completion (text, start, end) + const char *text; + int start, end; + { + char **matches; + + matches = (char **)NULL; + + /* If this word is at the start of the line, then it is a command + to complete. Otherwise it is the name of a file in the current + directory. */ + if (start == 0) + matches = rl_completion_matches (text, command_generator); + + return (matches); + } + + /* Generator function for command completion. STATE lets us + know whether to start from scratch; without any state + (i.e. STATE == 0), then we start at the top of the list. */ + char * + command_generator (text, state) + const char *text; + int state; + { + static int list_index, len; + char *name; + + /* If this is a new word to complete, initialize now. This + includes saving the length of TEXT for efficiency, and + initializing the index variable to 0. */ + if (!state) + { + list_index = 0; + len = strlen (text); + } + + /* Return the next name which partially matches from the + command list. */ + while (name = commands[list_index].name) + { + list_index++; + + if (strncmp (name, text, len) == 0) + return (dupstr(name)); + } + + /* If no names matched, then return NULL. */ + return ((char *)NULL); + } + + /* **************************************************************** */ + /* */ + /* FileMan Commands */ + /* */ + /* **************************************************************** */ + + /* String to pass to system (). This is for the LIST, VIEW and RENAME + commands. */ + static char syscom[1024]; + + /* List the file(s) named in arg. */ + com_list (arg) + char *arg; + { + if (!arg) + arg = ""; + + sprintf (syscom, "ls -FClg %s", arg); + return (system (syscom)); + } + + com_view (arg) + char *arg; + { + if (!valid_argument ("view", arg)) + return 1; + + sprintf (syscom, "more %s", arg); + return (system (syscom)); + } + + com_rename (arg) + char *arg; + { + too_dangerous ("rename"); + return (1); + } + + com_stat (arg) + char *arg; + { + struct stat finfo; + + if (!valid_argument ("stat", arg)) + return (1); + + if (stat (arg, &finfo) == -1) + { + perror (arg); + return (1); + } + + printf ("Statistics for `%s':\n", arg); + + printf ("%s has %d link%s, and is %d byte%s in length.\n", arg, + finfo.st_nlink, + (finfo.st_nlink == 1) ? "" : "s", + finfo.st_size, + (finfo.st_size == 1) ? "" : "s"); + printf ("Inode Last Change at: %s", ctime (&finfo.st_ctime)); + printf (" Last access at: %s", ctime (&finfo.st_atime)); + printf (" Last modified at: %s", ctime (&finfo.st_mtime)); + return (0); + } + + com_delete (arg) + char *arg; + { + too_dangerous ("delete"); + return (1); + } + + /* Print out help for ARG, or for all of the commands if ARG is + not present. */ + com_help (arg) + char *arg; + { + register int i; + int printed = 0; + + for (i = 0; commands[i].name; i++) + { + if (!*arg || (strcmp (arg, commands[i].name) == 0)) + { + printf ("%s\t\t%s.\n", commands[i].name, commands[i].doc); + printed++; + } + } + + if (!printed) + { + printf ("No commands match `%s'. Possibilties are:\n", arg); + + for (i = 0; commands[i].name; i++) + { + /* Print in six columns. */ + if (printed == 6) + { + printed = 0; + printf ("\n"); + } + + printf ("%s\t", commands[i].name); + printed++; + } + + if (printed) + printf ("\n"); + } + return (0); + } + + /* Change to the directory ARG. */ + com_cd (arg) + char *arg; + { + if (chdir (arg) == -1) + { + perror (arg); + return 1; + } + + com_pwd (""); + return (0); + } + + /* Print out the current working directory. */ + com_pwd (ignore) + char *ignore; + { + char dir[1024], *s; + + s = getcwd (dir, sizeof(dir) - 1); + if (s == 0) + { + printf ("Error getting pwd: %s\n", dir); + return 1; + } + + printf ("Current directory is %s\n", dir); + return 0; + } + + /* The user wishes to quit using this program. Just set DONE + non-zero. */ + com_quit (arg) + char *arg; + { + done = 1; + return (0); + } + + /* Function which tells you that you can't do this. */ + too_dangerous (caller) + char *caller; + { + fprintf (stderr, + "%s: Too dangerous for me to distribute.\n" + caller); + fprintf (stderr, "Write it yourself.\n"); + } + + /* Return non-zero if ARG is a valid argument for CALLER, + else print an error message and return zero. */ + int + valid_argument (caller, arg) + char *caller, *arg; + { + if (!arg || !*arg) + { + fprintf (stderr, "%s: Argument required.\n", caller); + return (0); + } + + return (1); + } + + +File: readline.info, Node: Concept Index, Next: Function and Variable Index, Prev: Programming with GNU Readline, Up: Top + +Concept Index +************* + +* Menu: + +* command editing: Readline Bare Essentials. +* editing command lines: Readline Bare Essentials. +* initialization file, readline: Readline Init File. +* interaction, readline: Readline Interaction. +* kill ring: Readline Killing Commands. +* killing text: Readline Killing Commands. +* notation, readline: Readline Bare Essentials. +* readline, function: Basic Behavior. +* variables, readline: Readline Init File Syntax. +* yanking text: Readline Killing Commands. + + +File: readline.info, Node: Function and Variable Index, Prev: Concept Index, Up: Top + +Function and Variable Index +*************************** + +* Menu: + +* _rl_digit_p: Utility Functions. +* _rl_digit_value: Utility Functions. +* _rl_lowercase_p: Utility Functions. +* _rl_to_lower: Utility Functions. +* _rl_to_upper: Utility Functions. +* _rl_uppercase_p: Utility Functions. +* abort (C-g): Miscellaneous Commands. +* accept-line (Newline or Return): Commands For History. +* backward-char (C-b): Commands For Moving. +* backward-delete-char (Rubout): Commands For Text. +* backward-kill-line (C-x Rubout): Commands For Killing. +* backward-kill-word (M-<DEL>): Commands For Killing. +* backward-word (M-b): Commands For Moving. +* beginning-of-history (M-<): Commands For History. +* beginning-of-line (C-a): Commands For Moving. +* bell-style: Readline Init File Syntax. +* call-last-kbd-macro (C-x e): Keyboard Macros. +* capitalize-word (M-c): Commands For Text. +* character-search (C-]): Miscellaneous Commands. +* character-search-backward (M-C-]): Miscellaneous Commands. +* clear-screen (C-l): Commands For Moving. +* comment-begin: Readline Init File Syntax. +* complete (<TAB>): Commands For Completion. +* completion-query-items: Readline Init File Syntax. +* convert-meta: Readline Init File Syntax. +* copy-backward-word (): Commands For Killing. +* copy-forward-word (): Commands For Killing. +* copy-region-as-kill (): Commands For Killing. +* delete-char (C-d): Commands For Text. +* delete-char-or-list (): Commands For Completion. +* delete-horizontal-space (): Commands For Killing. +* digit-argument (M-0, M-1, ... M--): Numeric Arguments. +* disable-completion: Readline Init File Syntax. +* do-uppercase-version (M-a, M-b, M-X, ...): Miscellaneous Commands. +* downcase-word (M-l): Commands For Text. +* dump-functions (): Miscellaneous Commands. +* dump-macros (): Miscellaneous Commands. +* dump-variables (): Miscellaneous Commands. +* editing-mode: Readline Init File Syntax. +* enable-keypad: Readline Init File Syntax. +* end-kbd-macro (C-x )): Keyboard Macros. +* end-of-history (M->): Commands For History. +* end-of-line (C-e): Commands For Moving. +* exchange-point-and-mark (C-x C-x): Miscellaneous Commands. +* expand-tilde: Readline Init File Syntax. +* forward-backward-delete-char (): Commands For Text. +* forward-char (C-f): Commands For Moving. +* forward-search-history (C-s): Commands For History. +* forward-word (M-f): Commands For Moving. +* history-preserve-point: Readline Init File Syntax. +* history-search-backward (): Commands For History. +* history-search-forward (): Commands For History. +* horizontal-scroll-mode: Readline Init File Syntax. +* input-meta: Readline Init File Syntax. +* insert-comment (M-#): Miscellaneous Commands. +* insert-completions (M-*): Commands For Completion. +* isearch-terminators: Readline Init File Syntax. +* keymap: Readline Init File Syntax. +* kill-line (C-k): Commands For Killing. +* kill-region (): Commands For Killing. +* kill-whole-line (): Commands For Killing. +* kill-word (M-d): Commands For Killing. +* mark-modified-lines: Readline Init File Syntax. +* mark-symlinked-directories: Readline Init File Syntax. +* match-hidden-files: Readline Init File Syntax. +* menu-complete (): Commands For Completion. +* meta-flag: Readline Init File Syntax. +* next-history (C-n): Commands For History. +* non-incremental-forward-search-history (M-n): Commands For History. +* non-incremental-reverse-search-history (M-p): Commands For History. +* output-meta: Readline Init File Syntax. +* overwrite-mode (): Commands For Text. +* page-completions: Readline Init File Syntax. +* possible-completions (M-?): Commands For Completion. +* prefix-meta (<ESC>): Miscellaneous Commands. +* previous-history (C-p): Commands For History. +* quoted-insert (C-q or C-v): Commands For Text. +* re-read-init-file (C-x C-r): Miscellaneous Commands. +* readline: Basic Behavior. +* redraw-current-line (): Commands For Moving. +* reverse-search-history (C-r): Commands For History. +* revert-line (M-r): Miscellaneous Commands. +* rl_add_defun: Function Naming. +* rl_add_funmap_entry: Associating Function Names and Bindings. +* rl_add_undo: Allowing Undoing. +* rl_alphabetic: Utility Functions. +* rl_already_prompted: Readline Variables. +* rl_attempted_completion_function: Completion Variables. +* rl_attempted_completion_over: Completion Variables. +* rl_basic_quote_characters: Completion Variables. +* rl_basic_word_break_characters: Completion Variables. +* rl_begin_undo_group: Allowing Undoing. +* rl_bind_key: Binding Keys. +* rl_bind_key_in_map: Binding Keys. +* rl_binding_keymap: Readline Variables. +* rl_callback_handler_install: Alternate Interface. +* rl_callback_handler_remove: Alternate Interface. +* rl_callback_read_char: Alternate Interface. +* rl_catch_signals: Readline Signal Handling. +* rl_catch_sigwinch: Readline Signal Handling. +* rl_char_is_quoted_p: Completion Variables. +* rl_cleanup_after_signal: Readline Signal Handling. +* rl_clear_message: Redisplay. +* rl_clear_pending_input: Character Input. +* rl_clear_signals: Readline Signal Handling. +* rl_complete <1>: How Completing Works. +* rl_complete: Completion Functions. +* rl_complete_internal: Completion Functions. +* rl_completer_quote_characters: Completion Variables. +* rl_completer_word_break_characters: Completion Variables. +* rl_completion_append_character: Completion Variables. +* rl_completion_display_matches_hook: Completion Variables. +* rl_completion_entry_function <1>: Completion Variables. +* rl_completion_entry_function: How Completing Works. +* rl_completion_mark_symlink_dirs: Completion Variables. +* rl_completion_matches: Completion Functions. +* rl_completion_mode: Completion Functions. +* rl_completion_query_items: Completion Variables. +* rl_completion_suppress_append: Completion Variables. +* rl_completion_type: Completion Variables. +* rl_copy_keymap: Keymaps. +* rl_copy_text: Modifying Text. +* rl_crlf: Redisplay. +* rl_delete_text: Modifying Text. +* rl_deprep_term_function: Readline Variables. +* rl_deprep_terminal: Terminal Management. +* rl_ding: Utility Functions. +* rl_directory_completion_hook: Completion Variables. +* rl_discard_keymap: Keymaps. +* rl_dispatching: Readline Variables. +* rl_display_match_list: Utility Functions. +* rl_do_undo: Allowing Undoing. +* rl_done: Readline Variables. +* rl_editing_mode: Readline Variables. +* rl_end: Readline Variables. +* rl_end_undo_group: Allowing Undoing. +* rl_erase_empty_line: Readline Variables. +* rl_event_hook: Readline Variables. +* rl_execute_next: Character Input. +* rl_executing_keymap: Readline Variables. +* rl_executing_macro: Readline Variables. +* rl_expand_prompt: Redisplay. +* rl_explicit_arg: Readline Variables. +* rl_extend_line_buffer: Utility Functions. +* rl_filename_completion_desired: Completion Variables. +* rl_filename_completion_function: Completion Functions. +* rl_filename_dequoting_function: Completion Variables. +* rl_filename_quote_characters: Completion Variables. +* rl_filename_quoting_desired: Completion Variables. +* rl_filename_quoting_function: Completion Variables. +* rl_forced_update_display: Redisplay. +* rl_free_line_state: Readline Signal Handling. +* rl_free_undo_list: Allowing Undoing. +* rl_function_dumper: Associating Function Names and Bindings. +* rl_function_of_keyseq: Associating Function Names and Bindings. +* rl_funmap_names: Associating Function Names and Bindings. +* rl_generic_bind: Binding Keys. +* rl_get_keymap: Keymaps. +* rl_get_keymap_by_name: Keymaps. +* rl_get_keymap_name: Keymaps. +* rl_get_screen_size: Readline Signal Handling. +* rl_get_termcap: Miscellaneous Functions. +* rl_getc: Character Input. +* rl_getc_function: Readline Variables. +* rl_gnu_readline_p: Readline Variables. +* rl_ignore_completion_duplicates: Completion Variables. +* rl_ignore_some_completions_function: Completion Variables. +* rl_inhibit_completion: Completion Variables. +* rl_initialize: Utility Functions. +* rl_insert_completions: Completion Functions. +* rl_insert_text: Modifying Text. +* rl_instream: Readline Variables. +* rl_invoking_keyseqs: Associating Function Names and Bindings. +* rl_invoking_keyseqs_in_map: Associating Function Names and Bindings. +* rl_kill_text: Modifying Text. +* rl_last_func: Readline Variables. +* rl_library_version: Readline Variables. +* rl_line_buffer: Readline Variables. +* rl_list_funmap_names: Associating Function Names and Bindings. +* rl_macro_bind: Miscellaneous Functions. +* rl_macro_dumper: Miscellaneous Functions. +* rl_make_bare_keymap: Keymaps. +* rl_make_keymap: Keymaps. +* rl_mark: Readline Variables. +* rl_message: Redisplay. +* rl_modifying: Allowing Undoing. +* rl_named_function: Associating Function Names and Bindings. +* rl_num_chars_to_read: Readline Variables. +* rl_numeric_arg: Readline Variables. +* rl_on_new_line: Redisplay. +* rl_on_new_line_with_prompt: Redisplay. +* rl_outstream: Readline Variables. +* rl_parse_and_bind: Binding Keys. +* rl_pending_input: Readline Variables. +* rl_point: Readline Variables. +* rl_possible_completions: Completion Functions. +* rl_pre_input_hook: Readline Variables. +* rl_prep_term_function: Readline Variables. +* rl_prep_terminal: Terminal Management. +* rl_prompt: Readline Variables. +* rl_push_macro_input: Modifying Text. +* rl_read_init_file: Binding Keys. +* rl_read_key: Character Input. +* rl_readline_name: Readline Variables. +* rl_readline_state: Readline Variables. +* rl_readline_version: Readline Variables. +* rl_redisplay: Redisplay. +* rl_redisplay_function: Readline Variables. +* rl_replace_line: Utility Functions. +* rl_reset_after_signal: Readline Signal Handling. +* rl_reset_line_state: Redisplay. +* rl_reset_terminal: Terminal Management. +* rl_resize_terminal: Readline Signal Handling. +* rl_restore_prompt: Redisplay. +* rl_save_prompt: Redisplay. +* rl_set_key: Binding Keys. +* rl_set_keyboard_input_timeout: Character Input. +* rl_set_keymap: Keymaps. +* rl_set_paren_blink_timeout: Miscellaneous Functions. +* rl_set_prompt: Redisplay. +* rl_set_screen_size: Readline Signal Handling. +* rl_set_signals: Readline Signal Handling. +* rl_show_char: Redisplay. +* rl_special_prefixes: Completion Variables. +* rl_startup_hook: Readline Variables. +* rl_stuff_char: Character Input. +* rl_terminal_name: Readline Variables. +* rl_tty_set_default_bindings: Terminal Management. +* rl_unbind_command_in_map: Binding Keys. +* rl_unbind_function_in_map: Binding Keys. +* rl_unbind_key: Binding Keys. +* rl_unbind_key_in_map: Binding Keys. +* rl_username_completion_function: Completion Functions. +* rl_variable_bind: Miscellaneous Functions. +* rl_variable_dumper: Miscellaneous Functions. +* self-insert (a, b, A, 1, !, ...): Commands For Text. +* set-mark (C-@): Miscellaneous Commands. +* show-all-if-ambiguous: Readline Init File Syntax. +* start-kbd-macro (C-x (): Keyboard Macros. +* transpose-chars (C-t): Commands For Text. +* transpose-words (M-t): Commands For Text. +* undo (C-_ or C-x C-u): Miscellaneous Commands. +* universal-argument (): Numeric Arguments. +* unix-line-discard (C-u): Commands For Killing. +* unix-word-rubout (C-w): Commands For Killing. +* upcase-word (M-u): Commands For Text. +* visible-stats: Readline Init File Syntax. +* yank (C-y): Commands For Killing. +* yank-last-arg (M-. or M-_): Commands For History. +* yank-nth-arg (M-C-y): Commands For History. +* yank-pop (M-y): Commands For Killing. + + + +Tag Table: +Node: Top1164 +Node: Command Line Editing1763 +Node: Introduction and Notation2414 +Node: Readline Interaction4032 +Node: Readline Bare Essentials5219 +Node: Readline Movement Commands7000 +Node: Readline Killing Commands7957 +Node: Readline Arguments9866 +Node: Searching10902 +Node: Readline Init File13045 +Node: Readline Init File Syntax14106 +Node: Conditional Init Constructs24989 +Node: Sample Init File27514 +Node: Bindable Readline Commands30698 +Node: Commands For Moving31748 +Node: Commands For History32597 +Node: Commands For Text35455 +Node: Commands For Killing38169 +Node: Numeric Arguments40120 +Node: Commands For Completion41248 +Node: Keyboard Macros42780 +Node: Miscellaneous Commands43339 +Node: Readline vi Mode46688 +Node: Programming with GNU Readline48506 +Node: Basic Behavior49474 +Node: Custom Functions52904 +Node: Readline Typedefs54382 +Node: Function Writing56011 +Node: Readline Variables57219 +Node: Readline Convenience Functions66642 +Node: Function Naming67624 +Node: Keymaps68876 +Node: Binding Keys70632 +Node: Associating Function Names and Bindings73558 +Node: Allowing Undoing75803 +Node: Redisplay78338 +Node: Modifying Text81409 +Node: Character Input82638 +Node: Terminal Management84418 +Node: Utility Functions85593 +Node: Miscellaneous Functions87932 +Node: Alternate Interface89996 +Node: A Readline Example92141 +Node: Readline Signal Handling94078 +Node: Custom Completers99681 +Node: How Completing Works100396 +Node: Completion Functions103394 +Node: Completion Variables106778 +Node: A Short Completion Example117049 +Node: Concept Index129602 +Node: Function and Variable Index130424 + +End Tag Table |