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diff --git a/doc/rluser.texinfo b/doc/rluser.texinfo index 755f7ca..9f088ff 100644 --- a/doc/rluser.texinfo +++ b/doc/rluser.texinfo @@ -7,10 +7,10 @@ This file documents the end user interface to the GNU command line editing features. It is to be an appendix to manuals for programs which use these features. There is a document entitled "readline.texinfo" -which contains both end-user and programmer documentation for the GNU -Readline Library. +which contains both end-user and programmer documentation for the +GNU Readline Library. -Copyright (C) 1988, 1991, 1993, 1996 Free Software Foundation, Inc. +Copyright (C) 1988-1999 Free Software Foundation, Inc. Authored by Brian Fox and Chet Ramey. @@ -36,11 +36,19 @@ into another language, under the above conditions for modified versions. @comment If you are including this manual as an appendix, then set the @comment variable readline-appendix. +@ifclear BashFeatures +@defcodeindex bt +@end ifclear + @node Command Line Editing @chapter Command Line Editing -This chapter describes the basic features of the @sc{GNU} +This chapter describes the basic features of the @sc{gnu} command line editing interface. +@ifset BashFeatures +Command line editing is provided by the Readline library, which is +used by several different programs, including Bash. +@end ifset @menu * Introduction and Notation:: Notation used in this text. @@ -50,6 +58,12 @@ command line editing interface. available for binding * Readline vi Mode:: A short description of how to make Readline behave like the vi editor. +@ifset BashFeatures +* Programmable Completion:: How to specify the possible completions for + a specific command. +* Programmable Completion Builtins:: Builtin commands to specify how to + complete arguments for a particular command. +@end ifset @end menu @node Introduction and Notation @@ -63,9 +77,19 @@ produced when the @key{k} key is pressed while the Control key is depressed. The text @key{M-k} is read as `Meta-K' and describes the character -produced when the meta key (if you have one) is depressed, and the @key{k} -key is pressed. If you do not have a meta key, the identical keystroke -can be generated by typing @key{ESC} @i{first}, and then typing @key{k}. +produced when the Meta key (if you have one) is depressed, and the @key{k} +key is pressed. +The Meta key is labeled @key{ALT} on many keyboards. +On keyboards with two keys labeled @key{ALT} (usually to either side of +the space bar), the @key{ALT} on the left side is generally set to +work as a Meta key. +The @key{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 @key{ALT} key, or another key working as +a Meta key, the identical keystroke can be generated by typing @key{ESC} +@i{first}, and then typing @key{k}. Either process is known as @dfn{metafying} the @key{k} key. The text @key{M-C-k} is read as `Meta-Control-k' and describes the @@ -75,6 +99,10 @@ In addition, several keys have their own names. Specifically, @key{DEL}, @key{ESC}, @key{LFD}, @key{SPC}, @key{RET}, and @key{TAB} all stand for themselves when seen in this text, or in an init file (@pxref{Readline Init File}). +If your keyboard lacks a @key{LFD} key, typing @key{C-j} will +produce the desired character. +The @key{RET} key may be labeled @key{Return} or @key{Enter} on +some keyboards. @node Readline Interaction @section Readline Interaction @@ -110,8 +138,8 @@ 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 +Sometimes you may mistype a character, and +not notice the error until you have typed several other characters. In that case, you can type @key{C-b} to move the cursor to the left, and then correct your mistake. Afterwards, you can move the cursor to the right with @key{C-f}. @@ -120,7 +148,7 @@ 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 +blank space created by the removal of the text. A list of the bare essentials for editing the text of an input line follows. @table @asis @@ -128,22 +156,28 @@ essentials for editing the text of an input line follows. Move back one character. @item @key{C-f} Move forward one character. -@item @key{DEL} +@item @key{DEL} or @key{Backspace} Delete the character to the left of the cursor. @item @key{C-d} Delete the character underneath the cursor. @item @w{Printing characters} Insert the character into the line at the cursor. -@item @key{C-_} +@item @key{C-_} or @key{C-x C-u} Undo the last editing command. You can undo all the way back to an empty line. @end table +@noindent +(Depending on your configuration, the @key{Backspace} key be set to +delete the character to the left of the cursor and the @key{DEL} key set +to delete the character underneath the cursor, like @key{C-d}, rather +than the character to the left of the cursor.) + @node Readline Movement Commands @subsection Readline Movement Commands -The above table describes the most basic possible keystrokes that you need +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 @key{C-b}, @key{C-f}, @key{C-d}, and @key{DEL}. Here are some commands for moving more rapidly @@ -175,6 +209,8 @@ operate on characters while meta keystrokes operate on words. @dfn{Killing} text means to delete the text from the line, but to save it away for later use, usually by @dfn{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. @@ -194,12 +230,14 @@ Here is the list of commands for killing text. Kill the text from the current cursor position to the end of the line. @item M-d -Kill from the cursor to the end of the current word, or if between +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 @key{M-f}. @item M-DEL -Kill from the cursor the start of the previous word, or if between +Kill from the cursor the start of the previous word, or, if between words, to the start of the previous word. +Word boundaries are the same as those used by @key{M-b}. @item C-w Kill from the cursor to the previous whitespace. This is different than @@ -231,7 +269,7 @@ start of the line, you might type @samp{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 (@key{-}), then the sign of the argument will be negative. Once +sign (@samp{-}), 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 @key{C-d} command an argument of 10, you could type @samp{M-1 0 C-d}. @@ -252,15 +290,18 @@ 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. -The characters present in the value of the @var{isearch-terminators} variable +To search backward in the history for a particular string, type +@key{C-r}. Typing @key{C-s} searches forward through the history. +The characters present in the value of the @code{isearch-terminators} variable are used to terminate an incremental search. If that variable has not been assigned a value, the @key{ESC} and @key{C-J} characters will terminate an incremental search. @key{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 @key{C-s} or -@key{C-r} as appropriate. + +To find other matching entries in the history list, type @key{C-r} or +@key{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 @@ -276,11 +317,11 @@ typed by the user or be part of the contents of the current line. @section Readline Init File @cindex initialization file, readline -Although the Readline library comes with a set of @code{emacs}-like +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 @dfn{inputrc} file in his home directory. +commands in an @dfn{inputrc} file, conventionally in his home directory. The name of this @ifset BashFeatures file is taken from the value of the shell variable @code{INPUTRC}. If @@ -326,6 +367,11 @@ change from the default Emacs-like key binding to use set editing-mode vi @end example +@ifset BashFeatures +The @w{@code{bind -V}} command lists the current Readline variable names +and values. @xref{Bash Builtins}. +@end ifset + A great deal of run-time behavior is changeable with the following variables. @@ -363,7 +409,7 @@ them; otherwise, they are simply listed. The default limit is @vindex convert-meta If set to @samp{on}, Readline will convert characters with the eighth bit set to an ASCII key sequence by stripping the eighth -bit and prepending an @key{ESC} character, converting them to a +bit and prefixing an @key{ESC} character, converting them to a meta-prefixed key sequence. The default value is @samp{on}. @item disable-completion @@ -469,7 +515,7 @@ completions. The default is @samp{off}. @item 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 +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. @@ -480,6 +526,12 @@ 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. +@ifset BashFeatures +The @w{@code{bind -p}} command displays Readline function names and +bindings in a format that can put directly into an initialization file. +@xref{Bash Builtins}. +@end ifset + @table @asis @item @w{@var{keyname}: @var{function-name} or @var{macro}} @var{keyname} is the name of a key spelled out in English. For example: @@ -497,7 +549,7 @@ expressed on the right hand side (that is, to insert the text @item @w{"@var{keyseq}": @var{function-name} or @var{macro}} @var{keyseq} differs from @var{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 +the key sequence in double quotes. Some @sc{gnu} Emacs style key escapes can be used, as in the following example, but the special character names are not recognized. @@ -515,7 +567,7 @@ the text @samp{Function Key 1}. @end table -The following GNU Emacs style escape sequences are available when +The following @sc{gnu} Emacs style escape sequences are available when specifying key sequences: @table @code @@ -528,12 +580,12 @@ an escape character @item @kbd{\\} backslash @item @kbd{\"} -@key{"} +@key{"}, a double quotation mark @item @kbd{\'} -@key{'} +@key{'}, a single quote or apostrophe @end table -In addition to the GNU Emacs style escape sequences, a second +In addition to the @sc{gnu} Emacs style escape sequences, a second set of backslash escapes is available: @table @code @@ -554,10 +606,10 @@ horizontal tab @item \v vertical tab @item \@var{nnn} -the character whose ASCII code is the octal value @var{nnn} +the character whose @code{ASCII} code is the octal value @var{nnn} (one to three digits) @item \x@var{nnn} -the character whose ASCII code is the hexadecimal value @var{nnn} +the character whose @code{ASCII} code is the hexadecimal value @var{nnn} (one to three digits) @end table @@ -762,6 +814,17 @@ $endif This section describes Readline commands that may be bound to key sequences. +@ifset BashFeatures +You can list your key bindings by executing +@w{@code{bind -P}} or, for a more terse format, suitable for an +@var{inputrc} file, @w{@code{bind -p}}. (@xref{Bash Builtins}.) +@end ifset + +Command names without an accompanying key sequence are unbound by default. +In the following descriptions, @var{point} refers to the current cursor +position, and @var{mark} refers to a cursor position saved by the +@code{set-mark} command. +The text between the point and mark is referred to as the @var{region}. @node Commands For Moving @subsection Commands For Moving @@ -783,7 +846,7 @@ Move forward to the end of the next word. Words are composed of letters and digits. @item backward-word (M-b) -Move back to the start of this, or the previous, word. Words are +Move back to the start of the current or previous word. Words are composed of letters and digits. @item clear-screen (C-l) @@ -846,9 +909,9 @@ for a string supplied by the user. @item history-search-forward () Search forward through the history for the string of characters -between the start of the current line and the current cursor -position (the @var{point}). This is a non-incremental search. By -default, this command is unbound. +between the start of the current line and the point. +This is a non-incremental search. +By default, this command is unbound. @item history-search-backward () Search backward through the history for the string of characters @@ -908,11 +971,11 @@ 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 don't work. +Negative arguments have no effect. @item 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. +Drag the word before point past the word after point, +moving point past that word as well. @item upcase-word (M-u) Uppercase the current (or following) word. With a negative argument, @@ -934,38 +997,36 @@ capitalize the previous word, but do not move the cursor. @ftable @code @item kill-line (C-k) -Kill the text from the current cursor position to the end of the line. +Kill the text from point to the end of the line. @item backward-kill-line (C-x Rubout) Kill backward to the beginning of the line. @item unix-line-discard (C-u) Kill backward from the cursor to the beginning of the current line. -The killed text is saved on the kill-ring. @item kill-whole-line () -Kill all characters on the current line, no matter where the -cursor is. By default, this is unbound. +Kill all characters on the current line, no matter point is. +By default, this is unbound. @item 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 @code{forward-word}. +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 @code{forward-word}. @item backward-kill-word (M-DEL) -Kill the word behind the cursor. Word boundaries are the same -as @code{backward-word}. +Kill the word behind point. +Word boundaries are the same as @code{backward-word}. @item 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. +Kill the word behind point, using white space as a word boundary. +The killed text is saved on the kill-ring. @item delete-horizontal-space () Delete all spaces and tabs around point. By default, this is unbound. @item kill-region () -Kill the text between the point and the @emph{mark} (saved -cursor position). This text is referred to as the @var{region}. +Kill the text in the current region. By default, this command is unbound. @item copy-region-as-kill () @@ -1109,7 +1170,7 @@ the text against lines from the history list for possible completion matches. @item complete-into-braces (M-@{) -Perform filename completion and return the list of possible completions +Perform filename completion and insert the list of possible completions enclosed within braces so the list is available to the shell (@pxref{Brace Expansion}). @@ -1138,7 +1199,7 @@ in the macro appear as if typed at the keyboard. @ftable @code @item re-read-init-file (C-x C-r) -Read in the contents of the inputrc file, and incorporate +Read in the contents of the @var{inputrc} file, and incorporate any bindings or variable assignments found there. @item abort (C-g) @@ -1192,7 +1253,8 @@ The value of the @code{comment-begin} variable is inserted at the beginning of the current line, and the line is accepted as if a newline had been typed. @ifset BashFeatures -This makes the current line a shell comment. +The default value of @code{comment-begin} causes this command +to make the current line a shell comment. @end ifset @item dump-functions () @@ -1285,3 +1347,283 @@ switches you into `command' mode, where you can edit the text of the line with the standard @code{vi} movement keys, move to previous history lines with @samp{k} and subsequent lines with @samp{j}, and so forth. + +@ifset BashFeatures +@node Programmable Completion +@section Programmable Completion +@cindex programmable completion + +When word completion is attempted for an argument to a command for +which a completion specification (a @var{compspec}) has been defined +using the @code{complete} builtin (@pxref{Programmable Completion Builtins}), +the programmable completion facilities are invoked. + +First, the command name is identified. +If a compspec has been defined for that command, the +compspec is used to generate the list of possible completions for the word. +If the command word is a full pathname, a compspec for the full +pathname is searched for first. +If no compspec is found for the full pathname, an attempt is made to +find a compspec for the portion following the final slash. + +Once a compspec has been found, it is used to generate the list of +matching words. +If a compspec is not found, the default Bash completion +described above (@pxref{Commands For Completion}) is performed. + +First, the actions specified by the compspec are used. +Only matches which are prefixed by the word being completed are +returned. +When the @samp{-f} or @samp{-d} option is used for filename or +directory name completion, the shell variable @code{FIGNORE} is +used to filter the matches. +@xref{Bash Variables}, for a description of @code{FIGNORE}. + +Any completions specified by a filename expansion pattern to the +@samp{-G} option are generated next. +The words generated by the pattern need not match the word being completed. +The @code{GLOBIGNORE} shell variable is not used to filter the matches, +but the @code{FIGNORE} shell variable is used. + +Next, the string specified as the argument to the @samp{-W} option +is considered. +The string is first split using the characters in the @code{IFS} +special variable as delimiters. +Shell quoting is honored. +Each word is then expanded using +brace expansion, tilde expansion, parameter and variable expansion, +command substitution, arithmetic expansion, and pathname expansion, +as described above (@pxref{Shell Expansions}). +The results are split using the rules described above +(@pxref{Word Splitting}). +The results of the expansion are prefix-matched against the word being +completed, and the matching words become the possible completions. + +After these matches have been generated, any shell function or command +specified with the @samp{-F} and @samp{-C} options is invoked. +When the command or function is invoked, the @code{COMP_LINE} and +@code{COMP_POINT} variables are assigned values as described above +(@pxref{Bash Variables}). +If a shell function is being invoked, the @code{COMP_WORDS} and +@code{COMP_CWORD} variables are also set. +When the function or command is invoked, the first argument is the +name of the command whose arguments are being completed, the +second argument is the word being completed, and the third argument +is the word preceding the word being completed on the current command line. +No filtering of the generated completions against the word being completed +is performed; the function or command has complete freedom in generating +the matches. + +Any function specified with @samp{-F} is invoked first. +The function may use any of the shell facilities, including the +@code{compgen} builtin described below +(@pxref{Programmable Completion Builtins}), to generate the matches. +It must put the possible completions in the @code{COMPREPLY} array +variable. + +Next, any command specified with the @samp{-C} option is invoked +in an environment equivalent to command substitution. +It should print a list of completions, one per line, to +the standard output. +Backslash may be used to escape a newline, if necessary. + +After all of the possible completions are generated, any filter +specified with the @samp{-X} option is applied to the list. +The filter is a pattern as used for pathname expansion; a @samp{&} +in the pattern is replaced with the text of the word being completed. +A literal @samp{&} may be escaped with a backslash; the backslash +is removed before attempting a match. +Any completion that matches the pattern will be removed from the list. +A leading @samp{!} negates the pattern; in this case any completion +not matching the pattern will be removed. + +Finally, any prefix and suffix specified with the @samp{-P} and @samp{-S} +options are added to each member of the completion list, and the result is +returned to the Readline completion code as the list of possible +completions. + +If a compspec is found, whatever it generates is returned to the completion +code as the full set of possible completions. +The default Bash completions are not attempted, and the Readline +default of filename completion is disabled. + +@node Programmable Completion Builtins +@section Programmable Completion Builtins +@cindex completion builtins + +Two builtin commands are available to manipulate the programmable completion +facilities. + +@table @code +@item compgen +@btindex compgen +@example +@code{compgen [@var{option}] [@var{word}]} +@end example + +Generate possible completion matches for @var{word} according to +the @var{option}s, which may be any option accepted by the +@code{complete} +builtin with the exception of @samp{-p} and @samp{-r}, and write +the matches to the standard output. +When using the @samp{-F} or @samp{-C} options, the various shell variables +set by the programmable completion facilities, while available, will not +have useful values. + +The matches will be generated in the same way as if the programmable +completion code had generated them directly from a completion specification +with the same flags. +If @var{word} is specified, only those completions matching @var{word} +will be displayed. + +The return value is true unless an invalid option is supplied, or no +matches were generated. + +@item complete +@btindex complete +@example +@code{complete [-abcdefjkvu] [-A @var{action}] [-G @var{globpat}] [-W @var{wordlist}] +[-P @var{prefix}] [-S @var{suffix}] [-X @var{filterpat}] [-F @var{function}] +[-C @var{command}] @var{name} [@var{name} @dots{}]} +@code{complete -pr [@var{name} @dots{}]} +@end example + +Specify how arguments to each @var{name} should be completed. +If the @samp{-p} option is supplied, or if no options are supplied, existing +completion specifications are printed in a way that allows them to be +reused as input. +The @samp{-r} option removes a completion specification for +each @var{name}, or, if no @var{name}s are supplied, all +completion specifications. + +The process of applying these completion specifications when word completion +is attempted is described above (@pxref{Programmable Completion}). + +Other options, if specified, have the following meanings. +The arguments to the @samp{-G}, @samp{-W}, and @samp{-X} options +(and, if necessary, the @samp{-P} and @samp{-S} options) +should be quoted to protect them from expansion before the +@code{complete} builtin is invoked. + +@table @code +@item -A @var{action} +The @var{action} may be one of the following to generate a list of possible +completions: + +@table @code +@item alias +Alias names. May also be specified as @samp{-a}. + +@item arrayvar +Array variable names. + +@item binding +Readline key binding names (@pxref{Bindable Readline Commands}). + +@item builtin +Names of shell builtin commands. May also be specified as @samp{-b}. + +@item command +Command names. May also be specified as @samp{-c}. + +@item directory +Directory names. May also be specified as @samp{-d}. + +@item disabled +Names of disabled shell builtins. + +@item enabled +Names of enabled shell builtins. + +@item export +Names of exported shell variables. May also be specified as @samp{-e}. + +@item file +File names. May also be specified as @samp{-f}. + +@item function +Names of shell functions. + +@item helptopic +Help topics as accepted by the @code{help} builtin (@pxref{Bash Builtins}). + +@item hostname +Hostnames, as taken from the file specified by the +@code{HOSTFILE} shell variable (@pxref{Bash Variables}). + +@item job +Job names, if job control is active. May also be specified as @samp{-j}. + +@item keyword +Shell reserved words. May also be specified as @samp{-k}. + +@item running +Names of running jobs, if job control is active. + +@item setopt +Valid arguments for the @samp{-o} option to the @code{set} builtin +(@pxref{The Set Builtin}). + +@item shopt +Shell option names as accepted by the @code{shopt} builtin +(@pxref{Bash Builtins}). + +@item signal +Signal names. + +@item stopped +Names of stopped jobs, if job control is active. + +@item user +User names. May also be specified as @samp{-u}. + +@item variable +Names of all shell variables. May also be specified as @samp{-v}. +@end table + +@item -G @var{globpat} +The filename expansion pattern @var{globpat} is expanded to generate +the possible completions. + +@item -W @var{wordlist} +The @var{wordlist} is split using the characters in the +@code{IFS} special variable as delimiters, and each resultant word +is expanded. +The possible completions are the members of the resultant list which +match the word being completed. + +@item -C @var{command} +@var{command} is executed in a subshell environment, and its output is +used as the possible completions. + +@item -F @var{function} +The shell function @var{function} is executed in the current shell +environment. +When it finishes, the possible completions are retrieved from the value +of the @code{COMPREPLY} array variable. + +@item -X @var{filterpat} +@var{filterpat} is a pattern as used for filename expansion. +It is applied to the list of possible completions generated by the +preceding options and arguments, and each completion matching +@var{filterpat} is removed from the list. +A leading @samp{!} in @var{filterpat} negates the pattern; in this +case, any completion not matching @var{filterpat} is removed. + +@item -P @var{prefix} +@var{prefix} is added at the beginning of each possible completion +after all other options have been applied. + +@item -S @var{suffix} +@var{suffix} is appended to each possible completion +after all other options have been applied. +@end table + +The return value is true unless an invalid option is supplied, an option +other than @samp{-p} or @samp{-r} is supplied without a @var{name} +argument, an attempt is made to remove a completion specification for +a @var{name} for which no specification exists, or +an error occurs adding a completion specification. + +@end table +@end ifset |