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diff --git a/doc/readline.info-1 b/doc/readline.info-1 deleted file mode 100644 index 78bbd05..0000000 --- a/doc/readline.info-1 +++ /dev/null @@ -1,1322 +0,0 @@ -This is Info file readline.info, produced by Makeinfo-1.55 from the -input file rlman.texinfo. - - 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, 1991 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: Top, Next: Command Line Editing, Prev: (DIR), 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 Control key is depressed and the k key is struck. - - 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 struck. If you do not have 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::., for more info). - - -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 RETURN. You do not have to be at the end of -the line to press RETURN; 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. - - -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 miss typing a character that you wanted to type, -and not notice your 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 basic bare essentials for editing the text of an input line -follows. - -C-b - Move back one character. - -C-f - Move forward one character. - -DEL - 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-_ - Undo the last thing that you did. You can undo all the way back - to an empty line. - - -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 possible 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. - -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. 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. - -M-DEL - Kill from the cursor the start of the previous word, or if between - words, to the start of the previous word. - -C-w - Kill from the cursor to the previous whitespace. This is - different than M-DEL because the word boundaries differ. - - And, 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, 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' you type 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. - - -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 that you would like to -use a different set of keybindings. You can customize programs that -use Readline by putting commands in an "init" file in your 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 Syntax:: Syntax for the commands in the inputrc file. -* Conditional Init Constructs:: Conditional key bindings in the inputrc file. - - -File: readline.info, Node: Readline Init Syntax, Next: Conditional Init Constructs, Up: Readline Init File - -Readline Init 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 change the state of a few variables in Readline by using - the `set' command within the init file. Here is how you would - specify that you wish to use `vi' line editing commands: - - set editing-mode vi - - Right now, there are only a few variables which can be set; so - few, in fact, that we just list them here: - - `editing-mode' - The `editing-mode' variable controls which editing mode you - are using. 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'. - - `horizontal-scroll-mode' - This variable can be set to either `On' or `Off'. Setting it - to `On' means that the text of the lines that you edit 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'. - - `mark-modified-lines' - This variable, when set to `On', says to display an asterisk - (`*') at the start of history lines which have been modified. - This variable is `off' by default. - - `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 - `vi-comment' command is executed. The default value is `"#"'. - - `meta-flag' - If set to `on', Readline will enable eight-bit input (it will - not strip the eighth bit from the characters it reads), - regardless of what the terminal claims it can support. The - default value is `off'. - - `convert-meta' - If set to `on', Readline will convert characters with the - eigth bit set to an ASCII key sequence by stripping the eigth - bit and prepending an ESC character, converting them to a - meta-prefixed key sequence. The default value is `on'. - - `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'. - - `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. The default limit is `100'. - - `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. - - `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'. - - `expand-tilde' - If set to `on', tilde expansion is performed when Readline - attempts word completion. The default is `off'. - -Key Bindings - The syntax for controlling key bindings in the init file is - simple. First you have to know the name of the command that you - want to change. The following pages contain tables of the command - name, the default keybinding, and a short description of what the - command does. - - Once you know the name of the command, simply place the name of - the key you wish to bind the command to, a colon, and then the - name of the command on a line in the init file. The name of the - key can be expressed in different ways, depending on which is most - comfortable for you. - - 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', 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). - - "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 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 escape sequences are available when specifying - key sequences: - - ``\C-'' - control prefix - - ``\M-'' - meta prefix - - ``\e'' - an escape character - - ``\\'' - backslash - - ``\"'' - " - - ``\''' - ' - - When entering the text of a macro, single or double quotes - should be used to indicate a macro definition. Unquoted text - is assumed to be a function name. Backslash will quote any - character in the macro text, including " and '. For example, - the following binding will make `C-x \' insert a single \ - into the line: - "\C-x\\": "\\" - - -File: readline.info, Node: Conditional Init Constructs, Prev: Readline Init 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 three 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 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 it. 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 you saw in the previous example, terminates an - `$if' command. - -`$else' - Commands in this branch of the `$if' directive are executed if the - test fails. - - -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. - - -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 this, or the 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, Return)' - Accept the line regardless of where the cursor is. If this line is - non-empty, add it to the history list. If this line was a history - line, then restore the history line to its original state. - -`previous-history (C-p)' - Move `up' through the history list. - -`next-history (C-n)' - Move `down' through the history list. - -`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 you are - entering. - -`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 current 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 current 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). 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-., M-_)' - Insert last argument to the previous command (the last word on the - previous line). With an argument, behave exactly like - `yank-nth-arg'. - - -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 under the cursor. If the cursor is at the - beginning of the line, there are no characters in the line, and - the last character typed was not C-d, then return EOF. - -`backward-delete-char (Rubout)' - Delete the character behind the cursor. A numeric arg says to kill - the characters instead of deleting them. - -`quoted-insert (C-q, C-v)' - Add the next character that you type 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 argumentss don't work. - -`transpose-words (M-t)' - Drag the word behind the cursor past the word in front of the - cursor moving the cursor over that word as well. - -`upcase-word (M-u)' - Uppercase the current (or following) word. With a negative - argument, do the previous word, but do not move the cursor. - -`downcase-word (M-l)' - Lowercase the current (or following) word. With a negative - argument, do the previous word, but do not move the cursor. - -`capitalize-word (M-c)' - Capitalize the current (or following) word. With a negative - argument, do the previous word, but do not move the cursor. - - -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 the current cursor position 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. - Save the killed text on the kill-ring. - -`kill-whole-line ()' - Kill all characters on the current line, no matter where the - cursor is. By default, this is unbound. - -`kill-word (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 `forward-word'. - -`backward-kill-word (M-DEL)' - Kill the word behind the cursor. Word boundaries are the same as - `backward-word'. - -`unix-word-rubout (C-w)' - Kill the word behind the cursor, 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. - -`yank (C-y)' - Yank the top of the kill ring into the buffer at the current - cursor position. - -`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 ()' - Each time this is executed, the argument count is multiplied by - four. The argument count is initially one, so executing this - function the first time makes the argument count four. 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 do completion on the text before the cursor. This is - application-specific. Generally, if you are typing a filename - argument, you can do filename completion; if you are typing a - command, you can do command completion, if you are typing in a - symbol to GDB, you can do symbol name completion, if you are - typing in a variable to Bash, you can do variable name completion, - and so on. - -`possible-completions (M-?)' - List the possible completions of the text before the cursor. - -`insert-completions ()' - Insert all completions of the text before point that would have - been generated by `possible-completions'. By default, this is not - bound to a key. - - -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 your init 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, ...)' - Run the command that is bound to the corresoponding uppercase - character. - -`prefix-meta (ESC)' - Make the next character that you type be metafied. This is for - people without a meta key. Typing `ESC f' is equivalent to typing - `M-f'. - -`undo (C-_, C-x C-u)' - Incremental undo, separately remembered for each line. - -`revert-line (M-r)' - Undo all changes made to this line. This is like typing the `undo' - command enough times to get back to the beginning. - -`tilde-expand (M-~)' - Perform tilde expansion on the current word. - -`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. - - -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 (toggle-editing-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 following 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, 1994 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 Convenience Functions:: Functions which Readline supplies to - aid in writing your own -* 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 and then reads and returns -a single line of text from the user. The line `readline' returns is -allocated with `malloc ()'; you should `free ()' the line when you are -done with it. The declaration for `readline' in ANSI C is - - `char *readline (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, int (*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 Convenience Functions, 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. - -* Menu: - -* The Function Type:: C declarations to make code readable. -* Function Writing:: Variables and calling conventions. - - -File: readline.info, Node: The Function Type, Next: Function Writing, Up: Custom Functions - -The Function Type ------------------ - - For readabilty, we declare a new type of object, called "Function". -A `Function' is a C function which returns an `int'. The type -declaration for `Function' is: - -`typedef int Function ();' - - The reason for declaring this new type is to make it easier to write -code describing pointers to C functions. Let us say we had a variable -called FUNC which was a pointer to a function. Instead of the classic -C declaration - - `int (*)()func;' - -we may write - - `Function *func;' - -Similarly, there are - - typedef void VFunction (); - typedef char *CPFunction (); and - typedef char **CPPFunction (); - -for functions returning no value, `pointer to char', and `pointer to -pointer to char', respectively. - - -File: readline.info, Node: Function Writing, Prev: The Function Type, 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 - - `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. - - - 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::. - - - 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_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: char * rl_prompt - The prompt Readline uses. This is set from the argument to - `readline ()', and should not be assigned to directly. - - - Variable: char * rl_terminal_name - The terminal type, used for initialization. - - - Variable: 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. - - - Variable: FILE * rl_outstream - The stdio stream to which Readline performs output. - - - Variable: Function * rl_startup_hook - If non-zero, this is the address of a function to call just before - `readline' prints the first prompt. - - -File: readline.info, Node: Readline Convenience Functions, Next: Custom Completers, Prev: Custom Functions, 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'. -* Utility Functions:: Generally useful functions and hooks. - - -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 (char *name, Function *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 () - Returns a new, empty keymap. The space for the keymap is - allocated with `malloc ()'; you should `free ()' it when you are - done. - - - Function: Keymap rl_copy_keymap (Keymap map) - Return a new keymap which is a copy of MAP. - - - Function: Keymap rl_make_keymap () - 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 () - 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 (char *name) - Return the keymap matching NAME. 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 ------------- - - You associate keys 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. - - These functions manage key bindings. - - - Function: int rl_bind_key (int key, Function *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, Function *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_generic_bind (int type, 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::.). - - -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. - - - Function: Function * rl_named_function (char *name) - Return the function with name NAME. - - - Function: Function * rl_function_of_keyseq (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 it (one of `ISFUNC', `ISKMAP', or - `ISMACR'). - - - Function: char ** rl_invoking_keyseqs (Function *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 (Function *function, - Keymap map) - Return an array of strings representing the key sequences used to - invoke FUNCTION in the keymap MAP. - - -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. I could use an undo function for the stock -market. - - 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 -undo 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 () - 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 () - 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 free_undo_list () - Free the existing undo list. - - - Function: int rl_do_undo () - 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: int rl_redisplay () - Change what's displayed on the screen to reflect the current - contents of `rl_line_buffer'. - - - Function: int rl_forced_update_display () - Force the line to be updated and redisplayed, whether or not - Readline thinks the screen display is correct. - - - Function: int rl_on_new_line () - Tell the update routines that we have moved onto a new (empty) - line, usually after ouputting a newline. - - - Function: int rl_reset_line_state () - Reset the display state to a clean state and redisplay the current - line starting on a new line. - - - Function: int rl_message (va_alist) - The arguments are a string as would be supplied to `printf'. 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 () - Clear the message in the echo area. - |