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diff --git a/man-pages-posix-2017/man1p/vi.1p b/man-pages-posix-2017/man1p/vi.1p new file mode 100644 index 0000000..0c53c8b --- /dev/null +++ b/man-pages-posix-2017/man1p/vi.1p @@ -0,0 +1,6471 @@ +'\" et +.TH VI "1P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.\" +.SH NAME +vi +\(em screen-oriented (visual) display editor +.SH SYNOPSIS +.LP +.nf +vi \fB[\fR-rR\fB] [\fR-c \fIcommand\fB] [\fR-t \fItagstring\fB] [\fR-w \fIsize\fB] [\fIfile\fR...\fB]\fR +.fi +.SH DESCRIPTION +This utility shall be provided on systems that both support the User +Portability Utilities option and define the POSIX2_CHAR_TERM symbol. +On other systems it is optional. +.P +The +.IR vi +(visual) utility is a screen-oriented text editor. Only the open and +visual modes of the editor are described in POSIX.1\(hy2008; see the line editor +.IR ex +for additional editing capabilities used in +.IR vi . +The user can switch back and forth between +.IR vi +and +.IR ex +and execute +.IR ex +commands from within +.IR vi . +.P +This reference page uses the term +.IR "edit buffer" +to describe the current working text. No specific implementation is +implied by this term. All editing changes are performed on the edit +buffer, and no changes to it shall affect any file until an editor +command writes the file. +.P +When using +.IR vi , +the terminal screen acts as a window into the editing buffer. Changes +made to the editing buffer shall be reflected in the screen display; +the position of the cursor on the screen shall indicate the position +within the editing buffer. +.P +Certain terminals do not have all the capabilities necessary to support +the complete +.IR vi +definition. When these commands cannot be supported on such terminals, +this condition shall not produce an error message such as ``not an +editor command'' or report a syntax error. The implementation may +either accept the commands and produce results on the screen that are +the result of an unsuccessful attempt to meet the requirements of this volume of POSIX.1\(hy2017 +or report an error describing the terminal-related deficiency. +.SH OPTIONS +The +.IR vi +utility shall conform to the Base Definitions volume of POSIX.1\(hy2017, +.IR "Section 12.2" ", " "Utility Syntax Guidelines", +except that +.BR '\(pl' +may be recognized as an option delimiter as well as +.BR '\-' . +.P +The following options shall be supported: +.IP "\fB\-c\ \fIcommand\fR" 10 +See the +.IR ex +command description of the +.BR \-c +option. +.IP "\fB\-r\fP" 10 +See the +.IR ex +command description of the +.BR \-r +option. +.IP "\fB\-R\fP" 10 +See the +.IR ex +command description of the +.BR \-R +option. +.IP "\fB\-t\ \fItagstring\fR" 10 +See the +.IR ex +command description of the +.BR \-t +option. +.IP "\fB\-w\ \fIsize\fR" 10 +See the +.IR ex +command description of the +.BR \-w +option. +.SH OPERANDS +See the OPERANDS section of the +.IR ex +command for a description of the operands supported by the +.IR vi +command. +.SH STDIN +If standard input is not a terminal device, the results are undefined. +The standard input consists of a series of commands and input text, as +described in the EXTENDED DESCRIPTION section. +.P +If a read from the standard input returns an error, or if the editor +detects an end-of-file condition from the standard input, it shall be +equivalent to a SIGHUP asynchronous event. +.SH "INPUT FILES" +See the INPUT FILES section of the +.IR ex +command for a description of the input files supported by the +.IR vi +command. +.SH "ENVIRONMENT VARIABLES" +See the ENVIRONMENT VARIABLES section of the +.IR ex +command for the environment variables that affect the execution of the +.IR vi +command. +.SH "ASYNCHRONOUS EVENTS" +See the ASYNCHRONOUS EVENTS section of the +.IR ex +for the asynchronous events that affect the execution of the +.IR vi +command. +.SH STDOUT +If standard output is not a terminal device, undefined results occur. +.P +Standard output may be used for writing prompts to the user, for +informational messages, and for writing lines from the file. +.SH STDERR +If standard output is not a terminal device, undefined results occur. +.P +The standard error shall be used only for diagnostic messages. +.SH "OUTPUT FILES" +See the OUTPUT FILES section of the +.IR ex +command for a description of the output files supported by the +.IR vi +command. +.SH "EXTENDED DESCRIPTION" +If the terminal does not have the capabilities necessary to support an +unspecified portion of the +.IR vi +definition, implementations shall start initially in +.IR ex +mode or open mode. Otherwise, after initialization, +.IR vi +shall be in command mode; text input mode can be entered by one of +several commands used to insert or change text. In text input mode, +<ESC> +can be used to return to command mode; other uses of +<ESC> +are described later in this section; see +.IR "Terminate Command or Input Mode". +.SS "Initialization in ex and vi" +.P +See +.IR "Initialization in ex and vi" +for a description of +.IR ex +and +.IR vi +initialization for the +.IR vi +utility. +.SS "Command Descriptions in vi" +.P +The following symbols are used in this reference page to represent +arguments to commands. +.IP "\fIbuffer\fR" 8 +See the description of +.IR buffer +in the EXTENDED DESCRIPTION section of the +.IR ex +utility; see +.IR "Command Descriptions in ex". +.RS 8 +.P +In open and visual mode, when a command synopsis shows both [\c +.IR buffer ] +and [\c +.IR count ] +preceding the command name, they can be specified in either order. +.RE +.IP "\fIcount\fR" 8 +A positive integer used as an optional argument to most commands, +either to give a repeat count or as a size. This argument is optional +and shall default to 1 unless otherwise specified. +.RS 8 +.P +The Synopsis lines for the +.IR vi +commands +<control>\(hyG, +<control>\(hyL, +<control>\(hyR, +<control>\(hy], +.BR % , +.BR & , +.BR ^ , +.BR D , +.BR m , +.BR M , +.BR Q , +.BR u , +.BR U , +and +.BR ZZ +do not have +.IR count +as an optional argument. Regardless, it shall not be an error to +specify a +.IR count +to these commands, and any specified +.IR count +shall be ignored. +.RE +.IP "\fImotion\fR" 8 +An optional trailing argument used by the +.BR ! , +.BR < , +.BR > , +.BR c , +.BR d , +and +.BR y +commands, which is used to indicate the region of text that shall be +affected by the command. The motion can be either one of the command +characters repeated or one of several other +.IR vi +commands (listed in the following table). Each of the applicable +commands specifies the region of text matched by repeating the command; +each command that can be used as a motion command specifies the region +of text it affects. +.RS 8 +.P +Commands that take +.IR motion +arguments operate on either lines or characters, depending on the +circumstances. When operating on lines, all lines that fall partially +or wholly within the text region specified for the command shall be +affected. When operating on characters, only the exact characters in +the specified text region shall be affected. Each motion command +specifies this individually. +.P +When commands that may be motion commands are not used as motion +commands, they shall set the current position to the current line and +column as specified. +.P +The following commands shall be valid cursor motion commands: +.sp +.RS 4 +.nf + +<apostrophe> ( - j H +<carriage-return> ) $ k L +<comma> [[ % l M +<control>-H ]] _ n N +<control>-N { ; t T +<control>-P } ? w W +<grave-accent> \(ha b B +<newline> + e E +<space> | f F +<zero> / h G +.fi +.P +.RE +.P +Any +.IR count +that is specified to a command that has an associated motion command +shall be applied to the motion command. If a +.IR count +is applied to both the command and its associated motion command, the +effect shall be multiplicative. +.RE +.P +The following symbols are used in this section to specify locations +in the edit buffer: +.IP "\fIcurrent\ character\fP" 8 +.br +The character that is currently indicated by the cursor. +.IP "\fIend\ of\ a\ line\fP" 8 +.br +The point located between the last non-\c +<newline> +(if any) and the terminating +<newline> +of a line. For an empty line, this location coincides with the +beginning of the line. +.IP "\fIend\ of\ the\ edit\ buffer\fP" 8 +.br +The location corresponding to the end of the last line in the edit +buffer. +.P +The following symbols are used in this section to specify command +actions: +.IP "\fIbigword\fP" 8 +In the POSIX locale, +.IR vi +shall recognize four kinds of +.IR bigwords : +.RS 8 +.IP " 1." 4 +A maximal sequence of non-\c +<blank> +characters preceded and followed by +<blank> +characters or the beginning or end of a line or the edit buffer +.IP " 2." 4 +One or more sequential blank lines +.IP " 3." 4 +The first character in the edit buffer +.IP " 4." 4 +The last non-\c +<newline> +in the edit buffer +.RE +.IP "\fIword\fP" 8 +In the POSIX locale, +.IR vi +shall recognize five kinds of words: +.RS 8 +.IP " 1." 4 +A maximal sequence of letters, digits, and underscores, delimited at +both ends by: +.RS 4 +.IP -- 4 +Characters other than letters, digits, or underscores +.IP -- 4 +The beginning or end of a line +.IP -- 4 +The beginning or end of the edit buffer +.RE +.IP " 2." 4 +A maximal sequence of characters other than letters, digits, underscores, or +<blank> +characters, delimited at both ends by: +.RS 4 +.IP -- 4 +A letter, digit, underscore +.IP -- 4 +<blank> +characters +.IP -- 4 +The beginning or end of a line +.IP -- 4 +The beginning or end of the edit buffer +.RE +.IP " 3." 4 +One or more sequential blank lines +.IP " 4." 4 +The first character in the edit buffer +.IP " 5." 4 +The last non-\c +<newline> +in the edit buffer +.RE +.IP "\fIsection\ boundary\fR" 8 +.br +A +.IR "section boundary" +is one of the following: +.RS 8 +.IP " 1." 4 +A line whose first character is a +<form-feed> +.IP " 2." 4 +A line whose first character is an open curly brace (\c +.BR '{' ) +.IP " 3." 4 +A line whose first character is a +<period> +and whose second and third characters match a two-character pair in the +.BR sections +edit option (see +.IR ex ) +.IP " 4." 4 +A line whose first character is a +<period> +and whose only other character matches the first character of a +two-character pair in the +.BR sections +edit option, where the second character of the two-character pair is a +<space> +.IP " 5." 4 +The first line of the edit buffer +.IP " 6." 4 +The last line of the edit buffer if the last line of the edit buffer is +empty or if it is a +.BR ]] +or +.BR } +command; otherwise, the last non-\c +<newline> +of the last line of the edit buffer +.RE +.IP "\fIparagraph\ boundary\fR" 8 +.br +A +.IR "paragraph boundary" +is one of the following: +.RS 8 +.IP " 1." 4 +A section boundary +.IP " 2." 4 +A line whose first character is a +<period> +and whose second and third characters match a two-character pair in the +.BR paragraphs +edit option (see +.IR ex ) +.IP " 3." 4 +A line whose first character is a +<period> +and whose only other character matches the first character of a +two-character pair in the +.IR paragraphs +edit option, where the second character of the two-character pair is a +<space> +.IP " 4." 4 +One or more sequential blank lines +.RE +.IP "\fIremembered\ search\ direction\fR" 8 +.br +See the description of \fIremembered search direction\fP in +.IR ex . +.IP "\fIsentence\ boundary\fR" 8 +.br +A +.IR "sentence boundary" +is one of the following: +.RS 8 +.IP " 1." 4 +A paragraph boundary +.IP " 2." 4 +The first non-\c +<blank> +that occurs after a paragraph boundary +.IP " 3." 4 +The first non-\c +<blank> +that occurs after a +<period> +(\c +.BR '.' ), +<exclamation-mark> +(\c +.BR '!' ), +or +<question-mark> +(\c +.BR '?' ), +followed by two +<space> +characters or the end of a line; any number of closing parenthesis (\c +.BR ')' ), +closing brackets (\c +.BR ']' ), +double-quote (\c +.BR '\&"' ), +or single-quote (\c +<apostrophe>) +characters can appear between the punctuation mark and the two +<space> +characters or end-of-line +.RE +.P +In the remainder of the description of the +.IR vi +utility, the term ``buffer line'' refers to a line in the edit buffer +and the term ``display line'' refers to the line or lines on the +display screen used to display one buffer line. The term ``current +line'' refers to a specific ``buffer line''. +.P +If there are display lines on the screen for which there are no +corresponding buffer lines because they correspond to lines that would +be after the end of the file, they shall be displayed as a single +<tilde> +(\c +.BR '\(ti' ) +character, plus the terminating +<newline>. +.P +The last line of the screen shall be used to report errors or display +informational messages. It shall also be used to display the input for +``line-oriented commands'' (\c +.BR / , +.BR ? , +.BR : , +and +.BR ! ). +When a line-oriented command is executed, the editor shall enter text +input mode on the last line on the screen, using the respective command +characters as prompt characters. (In the case of the +.BR ! +command, the associated motion shall be entered by the user before the +editor enters text input mode.) The line entered by the user shall be +terminated by a +<newline>, +a non-\c +<control>\(hyV-escaped +<carriage-return>, +or unescaped +<ESC>. +It is unspecified if more characters than require a display width minus +one column number of screen columns can be entered. +.P +If any command is executed that overwrites a portion of the screen +other than the last line of the screen (for example, the +.IR ex +.BR suspend +or +.BR ! +commands), other than the +.IR ex +.BR shell +command, the user shall be prompted for a character before the screen +is refreshed and the edit session continued. +.P +<tab> +characters shall take up the number of columns on the screen set by the +.BR tabstop +edit option (see +.IR ex ), +unless there are less than that number of columns before the display +margin that will cause the displayed line to be folded; in this case, +they shall only take up the number of columns up to that boundary. +.P +The cursor shall be placed on the current line and relative to the +current column as specified by each command described in the following +sections. +.P +In open mode, if the current line is not already displayed, then it +shall be displayed. +.P +In visual mode, if the current line is not displayed, then the lines +that are displayed shall be expanded, scrolled, or redrawn to cause an +unspecified portion of the current line to be displayed. If the screen +is redrawn, no more than the number of display lines specified by the +value of the +.BR window +edit option shall be displayed (unless the current line cannot be +completely displayed in the number of display lines specified by the +.BR window +edit option) and the current line shall be positioned as close to the +center of the displayed lines as possible (within the constraints +imposed by the distance of the line from the beginning or end of the +edit buffer). If the current line is before the first line in the +display and the screen is scrolled, an unspecified portion of the +current line shall be placed on the first line of the display. If the +current line is after the last line in the display and the screen is +scrolled, an unspecified portion of the current line shall be placed on +the last line of the display. +.P +In visual mode, if a line from the edit buffer (other than the current +line) does not entirely fit into the lines at the bottom of the display +that are available for its presentation, the editor may choose not to +display any portion of the line. The lines of the display that do not +contain text from the edit buffer for this reason shall each consist of +a single +.BR '@' +character. +.P +In visual mode, the editor may choose for unspecified reasons to not +update lines in the display to correspond to the underlying edit buffer +text. The lines of the display that do not correctly correspond to text +from the edit buffer for this reason shall consist of a single +.BR '@' +character (plus the terminating +<newline>), +and the +<control>\(hyR +command shall cause the editor to update the screen to correctly +represent the edit buffer. +.P +Open and visual mode commands that set the current column set it to a +column position in the display, and not a character position in the +line. In this case, however, the column position in the display shall +be calculated for an infinite width display; for example, the column +related to a character that is part of a line that has been folded onto +additional screen lines will be offset from the display line column +where the buffer line begins, not from the beginning of a particular +display line. +.P +The display cursor column in the display is based on the value of the +current column, as follows, with each rule applied in turn: +.IP " 1." 4 +If the current column is after the last display line column used by the +displayed line, the display cursor column shall be set to the last +display line column occupied by the last non-\c +<newline> +in the current line; otherwise, the display cursor column shall be set +to the current column. +.IP " 2." 4 +If the character of which some portion is displayed in the display line +column specified by the display cursor column requires more than a +single display line column: +.RS 4 +.IP " a." 4 +If in text input mode, the display cursor column shall be adjusted to +the first display line column in which any portion of that character is +displayed. +.IP " b." 4 +Otherwise, the display cursor column shall be adjusted to the last +display line column in which any portion of that character is +displayed. +.RE +.P +The current column shall not be changed by these adjustments to the +display cursor column. +.P +If an error occurs during the parsing or execution of a +.IR vi +command: +.IP " *" 4 +The terminal shall be alerted. Execution of the +.IR vi +command shall stop, and the cursor (for example, the current line and +column) shall not be further modified. +.IP " *" 4 +Unless otherwise specified by the following command sections, it is +unspecified whether an informational message shall be displayed. +.IP " *" 4 +Any partially entered +.IR vi +command shall be discarded. +.IP " *" 4 +If the +.IR vi +command resulted from a +.BR map +expansion, all characters from that +.BR map +expansion shall be discarded, except as otherwise specified by the +.BR map +command (see +.IR ex ). +.IP " *" 4 +If the +.IR vi +command resulted from the execution of a buffer, no further commands +caused by the execution of the buffer shall be executed. +.SS "Page Backwards" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <control>-B +.fi +.P +.RE +.RE +.P +If in open mode, the +<control>\(hyB +command shall behave identically to the +.BR z +command. Otherwise, if the current line is the first line of the edit +buffer, it shall be an error. +.P +If the +.BR window +edit option is less than 3, display a screen where the last line of the +display shall be some portion of: +.sp +.RS 4 +.nf + +(\fIcurrent first line\fR) -1 +.fi +.P +.RE +.P +otherwise, display a screen where the first line of the display shall +be some portion of: +.sp +.RS 4 +.nf + +(\fIcurrent first line\fR) - \fIcount\fR x ((window edit option) -2) +.fi +.P +.RE +.P +If this calculation would result in a line that is before the first +line of the edit buffer, the first line of the display shall display +some portion of the first line of the edit buffer. +.P +.IR "Current line" : +If no lines from the previous display remain on the screen, set to the +last line of the display; otherwise, set to (\c +.IR line +\- the number of new lines displayed on this screen). +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Scroll Forward" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <control>-D +.fi +.P +.RE +.RE +.P +If the current line is the last line of the edit buffer, it shall be an +error. +.P +If no +.IR count +is specified, +.IR count +shall default to the +.IR count +associated with the previous +<control>\(hyD +or +<control>\(hyU +command. If there was no previous +<control>\(hyD +or +<control>\(hyU +command, +.IR count +shall default to the value of the +.BR scroll +edit option. +.P +If in open mode, write lines starting with the line after the current +line, until +.IR count +lines or the last line of the file have been written. +.P +.IR "Current line" : +If the current line + +.IR count +is past the last line of the edit buffer, set to the last line of the +edit buffer; otherwise, set to the current line + +.IR count . +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Scroll Forward by Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <control>-E +.fi +.P +.RE +.RE +.P +Display the line count lines after the last line currently displayed. +.P +If the last line of the edit buffer is displayed, it shall be an error. +If there is no line +.IR count +lines after the last line currently displayed, the last line of the +display shall display some portion of the last line of the edit +buffer. +.P +.IR "Current line" : +Unchanged if the previous current character is displayed; otherwise, +set to the first line displayed. +.P +.IR "Current column" : +Unchanged. +.SS "Page Forward" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <control>-F +.fi +.P +.RE +.RE +.P +If in open mode, the +<control>\(hyF +command shall behave identically to the +.BR z +command. Otherwise, if the current line is the last line of the edit +buffer, it shall be an error. +.P +If the +.BR window +edit option is less than 3, display a screen where the first line of +the display shall be some portion of: +.sp +.RS 4 +.nf + +(\fIcurrent last line\fR) +1 +.fi +.P +.RE +.P +otherwise, display a screen where the first line of the display shall +be some portion of: +.sp +.RS 4 +.nf + +(\fIcurrent first line\fR) + \fIcount\fR x ((window edit option) -2) +.fi +.P +.RE +.P +If this calculation would result in a line that is after the last line +of the edit buffer, the last line of the display shall display some +portion of the last line of the edit buffer. +.P +.IR "Current line" : +If no lines from the previous display remain on the screen, set to the +first line of the display; otherwise, set to (\c +.IR line ++ the number of new lines displayed on this screen). +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Display Information" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-G +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR ex +.BR file +command. +.SS "Move Cursor Backwards" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <control>-H +.br +\fB[\fIcount\fB]\fR h +.br +the current \fIerase\fP character (see stty) +.fi +.P +.RE +.RE +.P +If there are no characters before the current character on the current +line, it shall be an error. If there are less than +.IR count +previous characters on the current line, +.IR count +shall be adjusted to the number of previous characters on the line. +.P +If used as a motion command: +.IP " 1." 4 +The text region shall be from the character before the starting cursor +up to and including the +.IR count th +character before the starting cursor. +.IP " 2." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to (\c +.IR column +\- the number of columns occupied by +.IR count +characters ending with the previous current column). +.SS "Move Down" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <newline> +.br +\fB[\fIcount\fB]\fR <control>-J +.br +\fB[\fIcount\fB]\fR <control>-M +.br +\fB[\fIcount\fB]\fR <control>-N +.br +\fB[\fIcount\fB]\fR j +.br +\fB[\fIcount\fB]\fR <carriage-return> +.br +\fB[\fIcount\fB]\fR + +.fi +.P +.RE +.RE +.P +If there are less than +.IR count +lines after the current line in the edit buffer, it shall be an error. +.P +If used as a motion command: +.IP " 1." 4 +The text region shall include the starting line and the next +.IR count +\- 1 lines. +.IP " 2." 4 +Any text copied to a buffer shall be in line mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to +.IR "current line" + +.IR count . +.P +.IR "Current column" : +Set to non-\c +<blank> +for the +<carriage-return>, +<control>\(hyM, +and +.BR + +commands; otherwise, unchanged. +.SS "Clear and Redisplay" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-L +.fi +.P +.RE +.RE +.P +If in open mode, clear the screen and redisplay the current line. +Otherwise, clear and redisplay the screen. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Unchanged. +.SS "Move Up" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <control>-P +.br +\fB[\fIcount\fB]\fR k +.br +\fB[\fIcount\fB]\fR - +.fi +.P +.RE +.RE +.P +If there are less than +.IR count +lines before the current line in the edit buffer, it shall be an +error. +.P +If used as a motion command: +.IP " 1." 4 +The text region shall include the starting line and the previous +.IR count +lines. +.IP " 2." 4 +Any text copied to a buffer shall be in line mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to +.IR "current line" +\- +.IR count . +.P +.IR "Current column" : +Set to non-\c +<blank> +for the +.BR \- +command; otherwise, unchanged. +.SS "Redraw Screen" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-R +.fi +.P +.RE +.RE +.P +If any lines have been deleted from the display screen and flagged as +deleted on the terminal using the +.BR @ +convention (see the beginning of the EXTENDED DESCRIPTION section), +they shall be redisplayed to match the contents of the edit buffer. +.P +It is unspecified whether lines flagged with +.BR @ +because they do not fit on the terminal display shall be affected. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Unchanged. +.SS "Scroll Backward" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <control>-U +.fi +.P +.RE +.RE +.P +If the current line is the first line of the edit buffer, it shall be +an error. +.P +If no +.IR count +is specified, +.IR count +shall default to the +.IR count +associated with the previous +<control>\(hyD +or +<control>\(hyU +command. If there was no previous +<control>\(hyD +or +<control>\(hyU +command, +.IR count +shall default to the value of the +.BR scroll +edit option. +.P +.IR "Current line" : +If +.IR count +is greater than the current line, set to 1; otherwise, set to the +current line \- +.IR count . +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Scroll Backward by Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <control>-Y +.fi +.P +.RE +.RE +.P +Display the line +.IR count +lines before the first line currently displayed. +.P +If the current line is the first line of the edit buffer, it shall be +an error. If this calculation would result in a line that is before the +first line of the edit buffer, the first line of the display shall +display some portion of the first line of the edit buffer. +.P +.IR "Current line" : +Unchanged if the previous current character is displayed; otherwise, +set to the first line displayed. +.P +.IR "Current column" : +Unchanged. +.SS "Edit the Alternate File" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-\(ha +.fi +.P +.RE +.RE +This command shall be equivalent to the +.IR ex +.BR edit +command, with the alternate pathname as its argument. +.SS "Terminate Command or Input Mode" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<ESC> +.fi +.P +.RE +.RE +.P +If a partial +.IR vi +command (as defined by at least one, non-\c +.IR count +character) has been entered, discard the +.IR count +and the command character(s). +.P +Otherwise, if no command characters have been entered, and the +<ESC> +was the result of a map expansion, the terminal shall be alerted and +the +<ESC> +character shall be discarded, but it shall not be an error. +.P +Otherwise, it shall be an error. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Unchanged. +.SS "Search for tagstring" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-] +.fi +.P +.RE +.RE +.P +If the current character is not a word or +<blank>, +it shall be an error. +.P +This command shall be equivalent to the +.IR ex +.BR tag +command, with the argument to that command defined as follows. +.P +If the current character is a +<blank>: +.IP " 1." 4 +Skip all +<blank> +characters after the cursor up to the end of the line. +.IP " 2." 4 +If the end of the line is reached, it shall be an error. +.P +Then, the argument to the +.IR ex +.BR tag +command shall be the current character and all subsequent characters, +up to the first non-word character or the end of the line. +.SS "Move Cursor Forward" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR <space> +.br +\fB[\fIcount\fB]\fR l\fR (ell)\fR +.fi +.P +.RE +.RE +.P +If there are less than +.IR count +non-\c +<newline> +characters after the cursor on the current line, +.IR count +shall be adjusted to the number of non-\c +<newline> +characters after the cursor on the line. +.P +If used as a motion command: +.IP " 1." 4 +If the current or +.IR count th +character after the cursor is the last non-\c +<newline> +in the line, the text region shall be comprised of the current +character up to and including the last non-\c +<newline> +in the line. Otherwise, the text region shall be from the current +character up to, but not including, the +.IR count th +character after the cursor. +.IP " 2." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +If there are no non-\c +<newline> +characters after the current character on the current line, it shall be +an error. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to the last column that displays any portion of the +.IR count th +character after the current character. +.SS "Replace Text with Results from Shell Command" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR ! \fImotion shell-commands\fR <newline> +.fi +.P +.RE +.RE +.P +If the motion command is the +.BR ! +command repeated: +.IP " 1." 4 +If the edit buffer is empty and no +.IR count +was supplied, the command shall be the equivalent of the +.IR ex +.BR :read +.BR ! +command, with the text input, and no text shall be copied to any +buffer. +.IP " 2." 4 +Otherwise: +.RS 4 +.IP " a." 4 +If there are less than +.IR count +\-1 lines after the current line in the edit buffer, it shall be an +error. +.IP " b." 4 +The text region shall be from the current line up to and including the +next +.IR count +\-1 lines. +.RE +.P +Otherwise, the text region shall be the lines in which any character of +the text region specified by the motion command appear. +.P +Any text copied to a buffer shall be in line mode. +.P +This command shall be equivalent to the +.IR ex +.BR ! +command for the specified lines. +.SS "Move Cursor to End-of-Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR $ +.fi +.P +.RE +.RE +.P +It shall be an error if there are less than (\c +.IR count +\-1) lines after the current line in the edit buffer. +.P +If used as a motion command: +.IP " 1." 4 +If +.IR count +is 1: +.RS 4 +.IP " a." 4 +It shall be an error if the line is empty. +.IP " b." 4 +Otherwise, the text region shall consist of all characters from the +starting cursor to the last non-\c +<newline> +in the line, inclusive, and any text copied to a buffer shall be in +character mode. +.RE +.IP " 2." 4 +Otherwise, if the starting cursor position is at or before the first +non-\c +<blank> +in the line, the text region shall consist of the current and the next +.IR count +\-1 lines, and any text saved to a buffer shall be in line mode. +.IP " 3." 4 +Otherwise, the text region shall consist of all characters from the +starting cursor to the last non-\c +<newline> +in the line that is +.IR count +\-1 lines forward from the current line, and any text copied to a +buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to the +.IR "current line" ++ +.IR count \-1. +.P +.IR "Current column" : +The current column is set to the last display line column of the last +non-\c +<newline> +in the line, or column position 1 if the line is empty. +.P +The current column shall be adjusted to be on the last display line +column of the last non-\c +<newline> +of the current line as subsequent commands change the current line, +until a command changes the current column. +.SS "Move to Matching Character" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +% +.fi +.P +.RE +.RE +.P +If the character at the current position is not a parenthesis, bracket, +or curly brace, search forward in the line to the first one of those +characters. If no such character is found, it shall be an error. +.P +The matching character shall be the parenthesis, bracket, or curly +brace matching the parenthesis, bracket, or curly brace, respectively, +that was at the current position or that was found on the current +line. +.P +Matching shall be determined as follows, for an open parenthesis: +.IP " 1." 4 +Set a counter to 1. +.IP " 2." 4 +Search forwards until a parenthesis is found or the end of the edit +buffer is reached. +.IP " 3." 4 +If the end of the edit buffer is reached, it shall be an error. +.IP " 4." 4 +If an open parenthesis is found, increment the counter by 1. +.IP " 5." 4 +If a close parenthesis is found, decrement the counter by 1. +.IP " 6." 4 +If the counter is zero, the current character is the matching +character. +.P +Matching for a close parenthesis shall be equivalent, except that the +search shall be backwards, from the starting character to the beginning +of the buffer, a close parenthesis shall increment the counter by 1, +and an open parenthesis shall decrement the counter by 1. +.P +Matching for brackets and curly braces shall be equivalent, except that +searching shall be done for open and close brackets or open and close +curly braces. It is implementation-defined whether other characters +are searched for and matched as well. +.P +If used as a motion command: +.IP " 1." 4 +If the matching cursor was after the starting cursor in the edit +buffer, and the starting cursor position was at or before the first +non-\c +<blank> +non-\c +<newline> +in the starting line, and the matching cursor position was at or after +the last non-\c +<blank> +non-\c +<newline> +in the matching line, the text region shall consist of the current line +to the matching line, inclusive, and any text copied to a buffer shall +be in line mode. +.IP " 2." 4 +If the matching cursor was before the starting cursor in the edit +buffer, and the starting cursor position was at or after the last +non-\c +<blank> +non-\c +<newline> +in the starting line, and the matching cursor position was at or before +the first non-\c +<blank> +non-\c +<newline> +in the matching line, the text region shall consist of the current line +to the matching line, inclusive, and any text copied to a buffer shall +be in line mode. +.IP " 3." 4 +Otherwise, the text region shall consist of the starting character to +the matching character, inclusive, and any text copied to a buffer +shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to the line where the matching character is located. +.P +.IR "Current column" : +Set to the last column where any portion of the matching character is +displayed. +.SS "Repeat Substitution" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +& +.fi +.P +.RE +.RE +.P +Repeat the previous substitution command. This command shall be +equivalent to the +.IR ex +.BR & +command with the current line as its addresses, and without +.IR options , +.IR count , +or +.IR flags . +.SS "Return to Previous Context at Beginning of Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\&\(aq \fIcharacter\fR +.fi +.P +.RE +.RE +.P +It shall be an error if there is no line in the edit buffer marked by +.IR character . +.P +If used as a motion command: +.IP " 1." 4 +If the starting cursor is after the marked cursor, then the locations +of the starting cursor and the marked cursor in the edit buffer shall +be logically swapped. +.IP " 2." 4 +The text region shall consist of the starting line up to and including +the marked line, and any text copied to a buffer shall be in line +mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to the line referenced by the mark. +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Return to Previous Context" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\&` \fIcharacter\fR +.fi +.P +.RE +.RE +.P +It shall be an error if the marked line is no longer in the edit +buffer. If the marked line no longer contains a character in the saved +numbered character position, it shall be as if the marked position is +the first non-\c +<blank>. +.P +If used as a motion command: +.IP " 1." 4 +It shall be an error if the marked cursor references the same character +in the edit buffer as the starting cursor. +.IP " 2." 4 +If the starting cursor is after the marked cursor, then the locations +of the starting cursor and the marked cursor in the edit buffer shall +be logically swapped. +.IP " 3." 4 +If the starting line is empty or the starting cursor is at or before +the first non-\c +<blank> +non-\c +<newline> +of the starting line, and the marked cursor line is empty or the marked +cursor references the first character of the marked cursor line, the +text region shall consist of all lines containing characters from the +starting cursor to the line before the marked cursor line, inclusive, +and any text copied to a buffer shall be in line mode. +.IP " 4." 4 +Otherwise, if the marked cursor line is empty or the marked cursor +references a character at or before the first non-\c +<blank> +non-\c +<newline> +of the marked cursor line, the region of text shall be from the +starting cursor to the last non-\c +<newline> +of the line before the marked cursor line, inclusive, and any text +copied to a buffer shall be in character mode. +.IP " 5." 4 +Otherwise, the region of text shall be from the starting cursor +(inclusive), to the marked cursor (exclusive), and any text copied to a +buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to the line referenced by the mark. +.P +.IR "Current column" : +Set to the last column in which any portion of the character referenced +by the mark is displayed. +.SS "Return to Previous Section" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR [[ +.fi +.P +.RE +.RE +.P +Move the cursor backward through the edit buffer to the first character +of the previous section boundary, +.IR count +times. +.P +If used as a motion command: +.IP " 1." 4 +If the starting cursor was at the first character of the starting line +or the starting line was empty, and the first character of the boundary +was the first character of the boundary line, the text region shall +consist of the current line up to and including the line where the +.IR count th +next boundary starts, and any text copied to a buffer shall be in line +mode. +.IP " 2." 4 +If the boundary was the last line of the edit buffer or the last non-\c +<newline> +of the last line of the edit buffer, the text region shall consist of +the last character in the edit buffer up to and including the starting +character, and any text saved to a buffer shall be in character mode. +.IP " 3." 4 +Otherwise, the text region shall consist of the starting character up +to but not including the first character in the +.IR count th +next boundary, and any text copied to a buffer shall be in character +mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to the line where the +.IR count th +next boundary in the edit buffer starts. +.P +.IR "Current column" : +Set to the last column in which any portion of the first character of +the +.IR count th +next boundary is displayed, or column position 1 if the line is empty. +.SS "Move to Next Section" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR ]] +.fi +.P +.RE +.RE +.P +Move the cursor forward through the edit buffer to the first character +of the next section boundary, +.IR count +times. +.P +If used as a motion command: +.IP " 1." 4 +If the starting cursor was at the first character of the starting line +or the starting line was empty, and the first character of the boundary +was the first character of the boundary line, the text region shall +consist of the current line up to and including the line where the +.IR count th +previous boundary starts, and any text copied to a buffer shall be in +line mode. +.IP " 2." 4 +If the boundary was the first line of the edit buffer, the text region +shall consist of the first character in the edit buffer up to but not +including the starting character, and any text copied to a buffer shall +be in character mode. +.IP " 3." 4 +Otherwise, the text region shall consist of the first character in the +.IR count th +previous section boundary up to but not including the starting +character, and any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to the line where the +.IR count th +previous boundary in the edit buffer starts. +.P +.IR "Current column" : +Set to the last column in which any portion of the first character of +the +.IR count th +previous boundary is displayed, or column position 1 if the line is +empty. +.SS "Move to First Non-<blank> Position on Current Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\&\(ha +.fi +.P +.RE +.RE +If used as a motion command: +.IP " 1." 4 +If the line has no non-\c +<blank> +non-\c +<newline> +characters, or if the cursor is at the first non-\c +<blank> +non-\c +<newline> +of the line, it shall be an error. +.IP " 2." 4 +If the cursor is before the first non-\c +<blank> +non-\c +<newline> +of the line, the text region shall be comprised of the current +character, up to, but not including, the first non-\c +<blank> +non-\c +<newline> +of the line. +.IP " 3." 4 +If the cursor is after the first non-\c +<blank> +non-\c +<newline> +of the line, the text region shall be from the character before the +starting cursor up to and including the first non-\c +<blank> +non-\c +<newline> +of the line. +.IP " 4." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Current and Line Above" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR _ +.fi +.P +.RE +.RE +.P +If there are less than +.IR count +\-1 lines after the current line in the edit buffer, it shall be an +error. +.P +If used as a motion command: +.IP " 1." 4 +If +.IR count +is less than 2, the text region shall be the current line. +.IP " 2." 4 +Otherwise, the text region shall include the starting line and the next +.IR count +\-1 lines. +.IP " 3." 4 +Any text copied to a buffer shall be in line mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to current line + +.IR count +\-1. +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Move Back to Beginning of Sentence" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR ( +.fi +.P +.RE +.RE +.P +Move backward to the beginning of a sentence. This command shall be +equivalent to the +.BR [[ +command, with the exception that sentence boundaries shall be used +instead of section boundaries. +.SS "Move Forward to Beginning of Sentence" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR ) +.fi +.P +.RE +.RE +.P +Move forward to the beginning of a sentence. This command shall be +equivalent to the +.BR ]] +command, with the exception that sentence boundaries shall be used +instead of section boundaries. +.SS "Move Back to Preceding Paragraph" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR { +.fi +.P +.RE +.RE +.P +Move back to the beginning of the preceding paragraph. This command +shall be equivalent to the +.BR [[ +command, with the exception that paragraph boundaries shall be used +instead of section boundaries. +.SS "Move Forward to Next Paragraph" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR } +.fi +.P +.RE +.RE +.P +Move forward to the beginning of the next paragraph. This command +shall be equivalent to the +.BR ]] +command, with the exception that paragraph boundaries shall be used +instead of section boundaries. +.SS "Move to Specific Column Position" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR | +.fi +.P +.RE +.RE +.P +For the purposes of this command, lines that are too long for the +current display and that have been folded shall be treated as having a +single, 1\-based, number of columns. +.P +If there are less than +.IR count +columns in which characters from the current line are displayed on the +screen, +.IR count +shall be adjusted to be the last column in which any portion of the +line is displayed on the screen. +.P +If used as a motion command: +.IP " 1." 4 +If the line is empty, or the cursor character is the same as the +character on the +.IR count th +column of the line, it shall be an error. +.IP " 2." 4 +If the cursor is before the +.IR count th +column of the line, the text region shall be comprised of the current +character, up to but not including the character on the +.IR count th +column of the line. +.IP " 3." 4 +If the cursor is after the +.IR count th +column of the line, the text region shall be from the character before +the starting cursor up to and including the character on the +.IR count th +column of the line. +.IP " 4." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to the last column in which any portion of the character that is +displayed in the +.IR count +column of the line is displayed. +.SS "Reverse Find Character" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR , +.fi +.P +.RE +.RE +.P +If the last +.BR F , +.BR f , +.BR T , +or +.BR t +command was +.BR F , +.BR f , +.BR T , +or +.BR t , +this command shall be equivalent to an +.BR f , +.BR F , +.BR t , +or +.BR T +command, respectively, with the specified +.IR count +and the same search character. +.P +If there was no previous +.BR F , +.BR f , +.BR T , +or +.BR t +command, it shall be an error. +.SS "Repeat" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR . +.fi +.P +.RE +.RE +.P +Repeat the last +.BR ! , +.BR < , +.BR > , +.BR A , +.BR C , +.BR D , +.BR I , +.BR J , +.BR O , +.BR P , +.BR R , +.BR S , +.BR X , +.BR Y , +.BR a , +.BR c , +.BR d , +.BR i , +.BR o , +.BR p , +.BR r , +.BR s , +.BR x , +.BR y , +or +.BR ~ +command. It shall be an error if none of these commands have been +executed. Commands (other than commands that enter text input mode) +executed as a result of map expansions, shall not change the value of +the last repeatable command. +.P +Repeated commands with associated motion commands shall repeat the +motion command as well; however, any specified +.IR count +shall replace the +.IR count (s) +that were originally specified to the repeated command or its +associated motion command. +.P +If the motion component of the repeated command is +.BR f , +.BR F , +.BR t , +or +.BR T , +the repeated command shall not set the remembered search character for +the +.BR ; +and +.BR , +commands. +.P +If the repeated command is +.BR p +or +.BR P , +and the buffer associated with that command was a numeric buffer named +with a number less than 9, the buffer associated with the repeated +command shall be set to be the buffer named by the name of the previous +buffer logically incremented by 1. +.P +If the repeated character is a text input command, the input text +associated with that command is repeated literally: +.IP " *" 4 +Input characters are neither macro or abbreviation-expanded. +.IP " *" 4 +Input characters are not interpreted in any special way with the +exception that +<newline>, +<carriage-return>, +and +<control>\(hyT +behave as described in +.IR "Input Mode Commands in vi". +.P +.IR "Current line" : +Set as described for the repeated command. +.P +.IR "Current column" : +Set as described for the repeated command. +.SS "Find Regular Expression" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +/ +.fi +.P +.RE +.RE +.P +If the input line contains no non-\c +<newline> +characters, it shall be equivalent to a line containing only the +last regular expression encountered. The enhanced regular expressions +supported by +.IR vi +are described in +.IR "Regular Expressions in ex". +.P +Otherwise, the line shall be interpreted as one or more regular +expressions, optionally followed by an address offset or a +.IR vi +.BR z +command. +.P +If the regular expression is not the last regular expression on the +line, or if a line offset or +.BR z +command is specified, the regular expression shall be terminated by an +unescaped +.BR '/' +character, which shall not be used as part of the regular expression. +If the regular expression is not the first regular expression on the +line, it shall be preceded by zero or more +<blank> +characters, a +<semicolon>, +zero or more +<blank> +characters, and a leading +.BR '/' +character, which shall not be interpreted as part of the regular +expression. It shall be an error to precede any regular expression with +any characters other than these. +.P +Each search shall begin from the character after the first character of +the last match (or, if it is the first search, after the cursor). If +the +.BR wrapscan +edit option is set, the search shall continue to the character before +the starting cursor character; otherwise, to the end of the edit +buffer. It shall be an error if any search fails to find a match, and +an informational message to this effect shall be displayed. +.P +An optional address offset (see +.IR "Addressing in ex") +can be specified after the last regular expression by including a +trailing +.BR '/' +character after the regular expression and specifying the address +offset. This offset will be from the line containing the match for the +last regular expression specified. It shall be an error if the line +offset would indicate a line address less than 1 or greater than the +last line in the edit buffer. An address offset of zero shall be +supported. It shall be an error to follow the address offset with any +other characters than +<blank> +characters. +.P +If not used as a motion command, an optional +.BR z +command (see +.IR "Redraw Window") +can be specified after the last regular expression by including a +trailing +.BR '/' +character after the regular expression, zero or more +<blank> +characters, a +.BR 'z' , +zero or more +<blank> +characters, an optional new +.BR window +edit option value, zero or more +<blank> +characters, and a location character. The effect shall be as if the +.BR z +command was executed after the +.BR / +command. It shall be an error to follow the +.BR z +command with any other characters than +<blank> +characters. +.P +The remembered search direction shall be set to forward. +.P +If used as a motion command: +.IP " 1." 4 +It shall be an error if the last match references the same character in +the edit buffer as the starting cursor. +.IP " 2." 4 +If any address offset is specified, the last match shall be adjusted by +the specified offset as described previously. +.IP " 3." 4 +If the starting cursor is after the last match, then the locations of +the starting cursor and the last match in the edit buffer shall be +logically swapped. +.IP " 4." 4 +If any address offset is specified, the text region shall consist of +all lines containing characters from the starting cursor to the last +match line, inclusive, and any text copied to a buffer shall be in line +mode. +.IP " 5." 4 +Otherwise, if the starting line is empty or the starting cursor is at +or before the first non-\c +<blank> +non-\c +<newline> +of the starting line, and the last match line is empty or the last +match starts at the first character of the last match line, the text +region shall consist of all lines containing characters from the +starting cursor to the line before the last match line, inclusive, and +any text copied to a buffer shall be in line mode. +.IP " 6." 4 +Otherwise, if the last match line is empty or the last match begins at +a character at or before the first non-\c +<blank> +non-\c +<newline> +of the last match line, the region of text shall be from the current +cursor to the last non-\c +<newline> +of the line before the last match line, inclusive, and any text copied +to a buffer shall be in character mode. +.IP " 7." 4 +Otherwise, the region of text shall be from the current cursor +(inclusive), to the first character of the last match (exclusive), and +any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +If a match is found, set to the last matched line plus the address +offset, if any; otherwise, unchanged. +.P +.IR "Current column" : +Set to the last column on which any portion of the first character in +the last matched string is displayed, if a match is found; otherwise, +unchanged. +.SS "Move to First Character in Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +0 \fR(zero)\fR +.fi +.P +.RE +.RE +.P +Move to the first character on the current line. The character +.BR '0' +shall not be interpreted as a command if it is immediately preceded by +a digit. +.P +If used as a motion command: +.IP " 1." 4 +If the cursor character is the first character in the line, it shall be +an error. +.IP " 2." 4 +The text region shall be from the character before the cursor character +up to and including the first character in the line. +.IP " 3." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +The last column in which any portion of the first character in the line +is displayed, or if the line is empty, unchanged. +.SS "Execute an ex Command" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +: +.fi +.P +.RE +.RE +.P +Execute one or more +.IR ex +commands. +.P +If any portion of the screen other than the last line of the screen was +overwritten by any +.IR ex +command (except +.BR shell ), +.IR vi +shall display a message indicating that it is waiting for an input from +the user, and shall then read a character. This action may also be +taken for other, unspecified reasons. +.P +If the next character entered is a +.BR ':' , +another +.IR ex +command shall be accepted and executed. Any other character shall cause +the screen to be refreshed and +.IR vi +shall return to command mode. +.P +.IR "Current line" : +As specified for the +.IR ex +command. +.P +.IR "Current column" : +As specified for the +.IR ex +command. +.SS "Repeat Find" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR ; +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the last +.BR F , +.BR f , +.BR T , +or +.BR t +command, with the specified +.IR count , +and with the same search character used for the last +.BR F , +.BR f , +.BR T , +or +.BR t +command. If there was no previous +.BR F , +.BR f , +.BR T , +or +.BR t +command, it shall be an error. +.SS "Shift Left" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR < \fImotion\fR +.fi +.P +.RE +.RE +.P +If the motion command is the +.BR < +command repeated: +.IP " 1." 4 +If there are less than +.IR count +\-1 lines after the current line in the edit buffer, it shall be an +error. +.IP " 2." 4 +The text region shall be from the current line, up to and including the +next +.IR count +\-1 lines. +.P +Shift any line in the text region specified by the +.IR count +and motion command one shiftwidth (see the +.IR ex +.BR shiftwidth +option) toward the start of the line, as described by the +.IR ex +.BR < +command. The unshifted lines shall be copied to the unnamed buffer in +line mode. +.P +.IR "Current line" : +If the motion was from the current cursor position toward the end of +the edit buffer, unchanged. Otherwise, set to the first line in the +edit buffer that is part of the text region specified by the motion +command. +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Shift Right" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR > \fImotion\fR +.fi +.P +.RE +.RE +.P +If the motion command is the +.BR > +command repeated: +.IP " 1." 4 +If there are less than +.IR count +\-1 lines after the current line in the edit buffer, it shall be an +error. +.IP " 2." 4 +The text region shall be from the current line, up to and including the +next +.IR count +\-1 lines. +.P +Shift any line with characters in the text region specified by the +.IR count +and motion command one shiftwidth (see the +.IR ex +.BR shiftwidth +option) away from the start of the line, as described by the +.IR ex +.BR > +command. The unshifted lines shall be copied into the unnamed buffer in +line mode. +.P +.IR "Current line" : +If the motion was from the current cursor position toward the end of +the edit buffer, unchanged. Otherwise, set to the first line in the +edit buffer that is part of the text region specified by the +motion command. +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Scan Backwards for Regular Expression" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +? +.fi +.P +.RE +.RE +.P +Scan backwards; the +.BR ? +command shall be equivalent to the +.BR / +command (see +.IR "Find Regular Expression") +with the following exceptions: +.IP " 1." 4 +The input prompt shall be a +.BR '?' . +.IP " 2." 4 +Each search shall begin from the character before the first character +of the last match (or, if it is the first search, the character before +the cursor character). +.IP " 3." 4 +The search direction shall be from the cursor toward the beginning of +the edit buffer, and the +.BR wrapscan +edit option shall affect whether the search wraps to the end of the +edit buffer and continues. +.IP " 4." 4 +The remembered search direction shall be set to backward. +.SS "Execute" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +@\fIbuffer\fR +.fi +.P +.RE +.RE +.P +If the +.IR buffer +is specified as +.BR @ , +the last buffer executed shall be used. If no previous buffer has been +executed, it shall be an error. +.P +Behave as if the contents of the named buffer were entered as standard +input. After each line of a line-mode buffer, and all but the last line +of a character mode buffer, behave as if a +<newline> +were entered as standard input. +.P +If an error occurs during this process, an error message shall be +written, and no more characters resulting from the execution of this +command shall be processed. +.P +If a +.IR count +is specified, behave as if that count were entered as user input before +the characters from the +.BR @ +buffer were entered. +.P +.IR "Current line" : +As specified for the individual commands. +.P +.IR "Current column" : +As specified for the individual commands. +.SS "Reverse Case" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR \(ti +.fi +.P +.RE +.RE +.P +Reverse the case of the current character and the next +.IR count +\-1 characters, such that lowercase characters that have uppercase +counterparts shall be changed to uppercase characters, and uppercase +characters that have lowercase counterparts shall be changed to +lowercase characters, as prescribed by the current locale. No other +characters shall be affected by this command. +.P +If there are less than +.IR count +\-1 characters after the cursor in the edit buffer, +.IR count +shall be adjusted to the number of characters after the cursor in the +edit buffer minus 1. +.P +For the purposes of this command, the next character after the last +non-\c +<newline> +on the line shall be the next character in the edit buffer. +.P +.IR "Current line" : +Set to the line including the (\c +.IR count \-1)th +character after the cursor. +.P +.IR "Current column" : +Set to the last column in which any portion of the (\c +.IR count \-1)th +character after the cursor is displayed. +.SS "Append" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR a +.fi +.P +.RE +.RE +.P +Enter text input mode after the current cursor position. No characters +already in the edit buffer shall be affected by this command. A +.IR count +shall cause the input text to be appended +.IR count +\-1 more times to the end of the input. +.P +.IR "Current line/column" : +As specified for the text input commands (see +.IR "Input Mode Commands in vi"). +.SS "Append at End-of-Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR A +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR vi +command: +.sp +.RS 4 +.nf + +\fR$\fB [ \fIcount \fB]\fR a +.fi +.P +.RE +.P +(see +.IR "Append"). +.SS "Move Backward to Preceding Word" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR b +.fi +.P +.RE +.RE +.P +With the exception that words are used as the delimiter instead of +bigwords, this command shall be equivalent to the +.BR B +command. +.SS "Move Backward to Preceding Bigword" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR B +.fi +.P +.RE +.RE +.P +If the edit buffer is empty or the cursor is on the first character of +the edit buffer, it shall be an error. If less than +.IR count +bigwords begin between the cursor and the start of the edit buffer, +.IR count +shall be adjusted to the number of bigword beginnings between the +cursor and the start of the edit buffer. +.P +If used as a motion command: +.IP " 1." 4 +The text region shall be from the first character of the +.IR count th +previous bigword beginning up to but not including the cursor +character. +.IP " 2." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to the line containing the +.IR "current column" . +.P +.IR "Current column" : +Set to the last column upon which any part of the first character of +the +.IR count th +previous bigword is displayed. +.SS "Change" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR c \fImotion\fR +.fi +.P +.RE +.RE +.P +If the motion command is the +.BR c +command repeated: +.IP " 1." 4 +The buffer text shall be in line mode. +.IP " 2." 4 +If there are less than +.IR count +\-1 lines after the current line in the edit buffer, it shall be an +error. +.IP " 3." 4 +The text region shall be from the current line up to and including the +next +.IR count +\-1 lines. +.P +Otherwise, the buffer text mode and text region shall be as specified +by the motion command. +.P +The replaced text shall be copied into +.IR buffer , +if specified, and into the unnamed buffer. If the text to be replaced +contains characters from more than a single line, or the buffer text is +in line mode, the replaced text shall be copied into the numeric +buffers as well. +.P +If the buffer text is in line mode: +.IP " 1." 4 +Any lines that contain characters in the region shall be deleted, and +the editor shall enter text input mode at the beginning of a new line +which shall replace the first line deleted. +.IP " 2." 4 +If the +.BR autoindent +edit option is set, +.BR autoindent +characters equal to the +.BR autoindent +characters on the first line deleted shall be inserted as if entered by +the user. +.P +Otherwise, if characters from more than one line are in the region of +text: +.IP " 1." 4 +The text shall be deleted. +.IP " 2." 4 +Any text remaining in the last line in the text region shall be +appended to the first line in the region, and the last line in the +region shall be deleted. +.IP " 3." 4 +The editor shall enter text input mode after the last character not +deleted from the first line in the text region, if any; otherwise, on +the first column of the first line in the region. +.br +.P +Otherwise: +.IP " 1." 4 +If the glyph for +.BR '$' +is smaller than the region, the end of the region shall be marked with +a +.BR '$' . +.IP " 2." 4 +The editor shall enter text input mode, overwriting the region of +text. +.P +.IR "Current line/column" : +As specified for the text input commands (see +.IR "Input Mode Commands in vi"). +.SS "Change to End-of-Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR C +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR vi +command: +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR c$ +.fi +.P +.RE +.P +See the +.BR c +command. +.SS "Delete" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR d \fImotion\fR +.fi +.P +.RE +.RE +.P +If the motion command is the +.BR d +command repeated: +.IP " 1." 4 +The buffer text shall be in line mode. +.IP " 2." 4 +If there are less than +.IR count +\-1 lines after the current line in the edit buffer, it shall be an +error. +.IP " 3." 4 +The text region shall be from the current line up to and including the +next +.IR count +\-1 lines. +.P +Otherwise, the buffer text mode and text region shall be as specified +by the motion command. +.P +If in open mode, and the current line is deleted, and the line remains +on the display, an +.BR '@' +character shall be displayed as the first glyph of that line. +.P +Delete the region of text into +.IR buffer , +if specified, and into the unnamed buffer. If the text to be deleted +contains characters from more than a single line, or the buffer text is +in line mode, the deleted text shall be copied into the numeric +buffers, as well. +.P +.IR "Current line" : +Set to the first text region line that appears in the edit buffer, +unless that line has been deleted, in which case it shall be set to the +last line in the edit buffer, or line 1 if the edit buffer is empty. +.P +.IR "Current column" : +.IP " 1." 4 +If the line is empty, set to column position 1. +.IP " 2." 4 +Otherwise, if the buffer text is in line mode or the motion was from +the cursor toward the end of the edit buffer: +.RS 4 +.IP " a." 4 +If a character from the current line is displayed in the current +column, set to the last column that displays any portion of that +character. +.IP " b." 4 +Otherwise, set to the last column in which any portion of any character +in the line is displayed. +.RE +.IP " 3." 4 +Otherwise, if a character is displayed in the column that began the +text region, set to the last column that displays any portion of that +character. +.IP " 4." 4 +Otherwise, set to the last column in which any portion of any character +in the line is displayed. +.SS "Delete to End-of-Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB]\fR D +.fi +.P +.RE +.RE +.P +Delete the text from the current position to the end of the current +line; equivalent to the +.IR vi +command: +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB]\fR d$ +.fi +.P +.RE +.SS "Move to End-of-Word" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR e +.fi +.P +.RE +.RE +.P +With the exception that words are used instead of bigwords as the +delimiter, this command shall be equivalent to the +.BR E +command. +.SS "Move to End-of-Bigword" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR E +.fi +.P +.RE +.RE +.P +If the edit buffer is empty it shall be an error. If less than +.IR count +bigwords end between the cursor and the end of the edit buffer, +.IR count +shall be adjusted to the number of bigword endings between the cursor +and the end of the edit buffer. +.P +If used as a motion command: +.IP " 1." 4 +The text region shall be from the last character of the +.IR count th +next bigword up to and including the cursor character. +.IP " 2." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to the line containing the current column. +.P +.IR "Current column" : +Set to the last column upon which any part of the last character of the +.IR count th +next bigword is displayed. +.SS "Find Character in Current Line (Forward)" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR f \fIcharacter\fR +.fi +.P +.RE +.RE +.P +It shall be an error if +.IR count +occurrences of the character do not occur after the cursor in the +line. +.P +If used as a motion command: +.IP " 1." 4 +The text range shall be from the cursor character up to and including +the +.IR count th +occurrence of the specified character after the cursor. +.IP " 2." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to the last column in which any portion of the +.IR count th +occurrence of the specified character after the cursor appears in the +line. +.SS "Find Character in Current Line (Reverse)" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR F \fIcharacter\fR +.fi +.P +.RE +.RE +.P +It shall be an error if +.IR count +occurrences of the character do not occur before the cursor in the +line. +.P +If used as a motion command: +.IP " 1." 4 +The text region shall be from the +.IR count th +occurrence of the specified character before the cursor, up to, but not +including the cursor character. +.IP " 2." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to the last column in which any portion of the +.IR count th +occurrence of the specified character before the cursor appears in the +line. +.SS "Move to Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR G +.fi +.P +.RE +.RE +.P +If +.IR count +is not specified, it shall default to the last line of the edit buffer. +If +.IR count +is greater than the last line of the edit buffer, it shall be an +error. +.P +If used as a motion command: +.IP " 1." 4 +The text region shall be from the cursor line up to and including the +specified line. +.IP " 2." 4 +Any text copied to a buffer shall be in line mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Set to +.IR count +if +.IR count +is specified; otherwise, the last line. +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Move to Top of Screen" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR H +.fi +.P +.RE +.RE +.P +If the beginning of the line +.IR count +greater than the first line of which any portion appears on the display +does not exist, it shall be an error. +.P +If used as a motion command: +.IP " 1." 4 +If in open mode, the text region shall be the current line. +.IP " 2." 4 +Otherwise, the text region shall be from the starting line up to and +including (the first line of the display + +.IR count +\-1). +.IP " 3." 4 +Any text copied to a buffer shall be in line mode. +.P +If not used as a motion command: +.P +If in open mode, this command shall set the current column to non-\c +<blank> +and do nothing else. +.P +Otherwise, it shall set the current line and current column as +follows. +.P +.IR "Current line" : +Set to (the first line of the display + +.IR count +\-1). +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Insert Before Cursor" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR i +.fi +.P +.RE +.RE +.P +Enter text input mode before the current cursor position. No characters +already in the edit buffer shall be affected by this command. A +.IR count +shall cause the input text to be appended +.IR count +\-1 more times to the end of the input. +.P +.IR "Current line/column" : +As specified for the text input commands (see +.IR "Input Mode Commands in vi"). +.SS "Insert at Beginning of Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR I +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR vi +command ^[\c +.IR count ]\c +.BR i . +.SS "Join" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR J +.fi +.P +.RE +.RE +.P +If the current line is the last line in the edit buffer, it shall be an +error. +.P +This command shall be equivalent to the +.IR ex +.BR join +command with no addresses, and an +.IR ex +command +.IR count +value of 1 if +.IR count +was not specified or if a +.IR count +of 1 was specified, and an +.IR ex +command +.IR count +value of +.IR count +\-1 for any other value of +.IR count , +except that the current line and column shall be set as follows. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +The last column in which any portion of the character following the +last character in the initial line is displayed, or the last non-\c +<newline> +in the line if no characters were appended. +.SS "Move to Bottom of Screen" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR L +.fi +.P +.RE +.RE +.P +If the beginning of the line +.IR count +less than the last line of which any portion appears on the display +does not exist, it shall be an error. +.P +If used as a motion command: +.IP " 1." 4 +If in open mode, the text region shall be the current line. +.IP " 2." 4 +Otherwise, the text region shall include all lines from the starting +cursor line to (the last line of the display \-(\c +.IR count +\-1)). +.IP " 3." 4 +Any text copied to a buffer shall be in line mode. +.P +If not used as a motion command: +.IP " 1." 4 +If in open mode, this command shall set the current column to non-\c +<blank> +and do nothing else. +.IP " 2." 4 +Otherwise, it shall set the current line and current column as follows. +.P +.IR "Current line" : +Set to (the last line of the display \-(\c +.IR count +\-1)). +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Mark Position" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +m \fIletter\fR +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR ex +.BR mark +command with the specified character as an argument. +.SS "Move to Middle of Screen" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +M +.fi +.P +.RE +.RE +.P +The middle line of the display shall be calculated as follows: +.sp +.RS 4 +.nf + +(the top line of the display) + (((number of lines displayed) +1) /2) -1 +.fi +.P +.RE +.P +If used as a motion command: +.IP " 1." 4 +If in open mode, the text region shall be the current line. +.IP " 2." 4 +Otherwise, the text region shall include all lines from the starting +cursor line up to and including the middle line of the display. +.IP " 3." 4 +Any text copied to a buffer shall be in line mode. +.P +If not used as a motion command: +.P +If in open mode, this command shall set the current column to non-\c +<blank> +and do nothing else. +.P +Otherwise, it shall set the current line and current column as +follows. +.P +.IR "Current line" : +Set to the middle line of the display. +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Repeat Regular Expression Find (Forward)" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +n +.fi +.P +.RE +.RE +.P +If the remembered search direction was forward, the +.BR n +command shall be equivalent to the +.IR vi +.BR / +command with no characters entered by the user. Otherwise, it shall be +equivalent to the +.IR vi +.BR ? +command with no characters entered by the user. +.P +If the +.BR n +command is used as a motion command for the +.BR ! +command, the editor shall not enter text input mode on the last line on +the screen, and shall behave as if the user entered a single +.BR '!' +character as the text input. +.SS "Repeat Regular Expression Find (Reverse)" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +N +.fi +.P +.RE +.RE +.P +Scan for the next match of the last pattern given to +.BR / +or +.BR ? , +but in the reverse direction; this is the reverse of +.BR n . +.P +If the remembered search direction was forward, the +.BR N +command shall be equivalent to the +.IR vi +.BR ? +command with no characters entered by the user. Otherwise, it shall be +equivalent to the +.IR vi +.BR / +command with no characters entered by the user. If the +.BR N +command is used as a motion command for the +.BR ! +command, the editor shall not enter text input mode on the last line on +the screen, and shall behave as if the user entered a single +.BR ! +character as the text input. +.SS "Insert Empty Line Below" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +o +.fi +.P +.RE +.RE +.P +Enter text input mode in a new line appended after the current line. A +.IR count +shall cause the input text to be appended +.IR count +\-1 more times to the end of the already added text, each time +starting on a new, appended line. +.P +.IR "Current line/column" : +As specified for the text input commands (see +.IR "Input Mode Commands in vi"). +.SS "Insert Empty Line Above" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +O +.fi +.P +.RE +.RE +.P +Enter text input mode in a new line inserted before the current line. A +.IR count +shall cause the input text to be appended +.IR count +\-1 more times to the end of the already added text, each time +starting on a new, appended line. +.P +.IR "Current line/column" : +As specified for the text input commands (see +.IR "Input Mode Commands in vi"). +.SS "Put from Buffer Following" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB]\fR p +.fi +.P +.RE +.RE +.P +If no +.IR buffer +is specified, the unnamed buffer shall be used. +.P +If the buffer text is in line mode, the text shall be appended below +the current line, and each line of the buffer shall become a new line +in the edit buffer. A +.IR count +shall cause the buffer text to be appended +.IR count +\-1 more times to the end of the already added text, each time +starting on a new, appended line. +.P +If the buffer text is in character mode, the text shall be appended +into the current line after the cursor, and each line of the buffer +other than the first and last shall become a new line in the edit +buffer. A +.IR count +shall cause the buffer text to be appended +.IR count +\-1 more times to the end of the already added text, each time +starting after the last added character. +.P +.IR "Current line" : +If the buffer text is in line mode, set the line to line +1; otherwise, +unchanged. +.P +.IR "Current column" : +If the buffer text is in line mode: +.IP " 1." 4 +If there is a non-\c +<blank> +in the first line of the buffer, set to the last column on which any +portion of the first non-\c +<blank> +in the line is displayed. +.IP " 2." 4 +If there is no non-\c +<blank> +in the first line of the buffer, set to the last column on which any +portion of the last non-\c +<newline> +in the first line of the buffer is displayed. +.P +If the buffer text is in character mode: +.IP " 1." 4 +If the text in the buffer is from more than a single line, then set to +the last column on which any portion of the first character from the +buffer is displayed. +.IP " 2." 4 +Otherwise, if the buffer is the unnamed buffer, set to the last column +on which any portion of the last character from the buffer is +displayed. +.IP " 3." 4 +Otherwise, set to the first column on which any portion of the first +character from the buffer is displayed. +.SS "Put from Buffer Before" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB]\fR P +.fi +.P +.RE +.RE +.P +If no +.IR buffer +is specified, the unnamed buffer shall be used. +.P +If the buffer text is in line mode, the text shall be inserted above +the current line, and each line of the buffer shall become a new line +in the edit buffer. A +.IR count +shall cause the buffer text to be appended +.IR count +\-1 more times to the end of the already added text, each time +starting on a new, appended line. +.P +If the buffer text is in character mode, the text shall be inserted +into the current line before the cursor, and each line of the buffer +other than the first and last shall become a new line in the edit +buffer. A +.IR count +shall cause the buffer text to be appended +.IR count +\-1 more times to the end of the already added text, each time +starting after the last added character. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +If the buffer text is in line mode: +.IP " 1." 4 +If there is a non-\c +<blank> +in the first line of the buffer, set to the last column on which any +portion of that character is displayed. +.IP " 2." 4 +If there is no non-\c +<blank> +in the first line of the buffer, set to the last column on which any +portion of the last non-\c +<newline> +in the first line of the buffer is displayed. +.P +If the buffer text is in character mode: +.IP " 1." 4 +If the text in the buffer is from more than a single line, then set to +the last column on which any portion of the first character from the +buffer is displayed. +.IP " 2." 4 +Otherwise, if the buffer is the unnamed buffer, set to the last column +on which any portion of the last character from the buffer is displayed. +.IP " 3." 4 +Otherwise, set to the first column on which any portion of the first +character from the buffer is displayed. +.SS "Enter ex Mode" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +Q +.fi +.P +.RE +.RE +.P +Leave visual or open mode and enter +.IR ex +command mode. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Unchanged. +.SS "Replace Character" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR r \fIcharacter\fR +.fi +.P +.RE +.RE +.P +Replace the +.IR count +characters at and after the cursor with the specified character. If +there are less than +.IR count +non-\c +<newline> +characters at and after the cursor on the line, it shall be an error. +.P +If character is +<control>\(hyV, +any next character other than the +<newline> +shall be stripped of any special meaning and used as a literal +character. +.P +If character is +<ESC>, +no replacement shall be made and the current line and current column +shall be unchanged. +.P +If character is +<carriage-return> +or +<newline>, +.IR count +new lines shall be appended to the current line. All but the last of +these lines shall be empty. +.IR count +characters at and after the cursor shall be discarded, and any +remaining characters after the cursor in the current line shall be +moved to the last of the new lines. If the +.BR autoindent +edit option is set, they shall be preceded by the same number of +.BR autoindent +characters found on the line from which the command was executed. +.P +.IR "Current line" : +Unchanged unless the replacement character is a +<carriage-return> +or +<newline>, +in which case it shall be set to line + +.IR count . +.P +.IR "Current column" : +Set to the last column position on which a portion of the last replaced +character is displayed, or if the replacement character caused new +lines to be created, set to non-\c +<blank>. +.SS "Replace Characters" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +R +.fi +.P +.RE +.RE +.P +Enter text input mode at the current cursor position possibly +replacing text on the current line. A +.IR count +shall cause the input text to be appended +.IR count +\-1 more times to the end of the input. +.P +.IR "Current line/column" : +As specified for the text input commands (see +.IR "Input Mode Commands in vi"). +.SS "Substitute Character" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR s +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR vi +command: +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR c<space> +.fi +.P +.RE +.SS "Substitute Lines" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR S +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR vi +command: +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR c_ +.fi +.P +.RE +.SS "Move Cursor to Before Character (Forward)" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR t \fIcharacter\fR +.fi +.P +.RE +.RE +.P +It shall be an error if +.IR count +occurrences of the character do not occur after the cursor in the +line. +.P +If used as a motion command: +.IP " 1." 4 +The text region shall be from the cursor up to but not including the +.IR count th +occurrence of the specified character after the cursor. +.IP " 2." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to the last column in which any portion of the character before the +.IR count th +occurrence of the specified character after the cursor appears in the +line. +.SS "Move Cursor to After Character (Reverse)" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR T \fIcharacter\fR +.fi +.P +.RE +.RE +.P +It shall be an error if +.IR count +occurrences of the character do not occur before the cursor in the +line. +.P +If used as a motion command: +.IP " 1." 4 +If the character before the cursor is the specified character, it shall +be an error. +.IP " 2." 4 +The text region shall be from the character before the cursor up to but +not including the +.IR count th +occurrence of the specified character before the cursor. +.IP " 3." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to the last column in which any portion of the character after the +.IR count th +occurrence of the specified character before the cursor appears in the +line. +.SS "Undo" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +u +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR ex +.BR undo +command except that the current line and current column shall be set as +follows: +.P +.IR "Current line" : +Set to the first line added or changed if any; otherwise, move to the +line preceding any deleted text if one exists; otherwise, move to line 1. +.P +.IR "Current column" : +If undoing an +.IR ex +command, set to the first non-\c +<blank>. +.P +Otherwise, if undoing a text input command: +.IP " 1." 4 +If the command was a +.BR C , +.BR c , +.BR O , +.BR o , +.BR R , +.BR S , +or +.BR s +command, the current column shall be set to the value it held when the +text input command was entered. +.IP " 2." 4 +Otherwise, set to the last column in which any portion of the first +character after the deleted text is displayed, or, if no non-\c +<newline> +characters follow the text deleted from this line, set to the last column +in which any portion of the last non-\c +<newline> +in the line is displayed, or 1 if the line is empty. +.P +Otherwise, if a single line was modified (that is, not added or +deleted) by the +.BR u +command: +.IP " 1." 4 +If text was added or changed, set to the last column in which any +portion of the first character added or changed is displayed. +.IP " 2." 4 +If text was deleted, set to the last column in which any portion of the +first character after the deleted text is displayed, or, if no non-\c +<newline> +characters follow the deleted text, set to the last column in which any +portion of the last non-\c +<newline> +in the line is displayed, or 1 if the line is empty. +.P +Otherwise, set to non-\c +<blank>. +.SS "Undo Current Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +U +.fi +.P +.RE +.RE +.P +Restore the current line to its state immediately before the most +recent time that it became the current line. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to the first column in the line in which any portion of the first +character in the line is displayed. +.SS "Move to Beginning of Word" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR w +.fi +.P +.RE +.RE +.P +With the exception that words are used as the delimiter instead of +bigwords, this command shall be equivalent to the +.BR W +command. +.SS "Move to Beginning of Bigword" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR W +.fi +.P +.RE +.RE +.P +If the edit buffer is empty, it shall be an error. If there are less +than +.IR count +bigwords between the cursor and the end of the edit buffer, +.IR count +shall be adjusted to move the cursor to the last bigword in the edit +buffer. +.P +If used as a motion command: +.IP " 1." 4 +If the associated command is +.BR c , +.IR count +is 1, and the cursor is on a +<blank>, +the region of text shall be the current character and no further action +shall be taken. +.IP " 2." 4 +If there are less than +.IR count +bigwords between the cursor and the end of the edit buffer, then the +command shall succeed, and the region of text shall include the last +character of the edit buffer. +.IP " 3." 4 +If there are +<blank> +characters or an end-of-line that precede the +.IR count th +bigword, and the associated command is +.BR c , +the region of text shall be up to and including the last character +before the preceding +<blank> +characters or end-of-line. +.IP " 4." 4 +If there are +<blank> +characters or an end-of-line that precede the bigword, and the associated +command is +.BR d +or +.BR y , +the region of text shall be up to and including the last +<blank> +before the start of the bigword or end-of-line. +.IP " 5." 4 +Any text copied to a buffer shall be in character mode. +.P +If not used as a motion command: +.IP " 1." 4 +If the cursor is on the last character of the edit buffer, it shall be +an error. +.P +.IR "Current line" : +Set to the line containing the current column. +.P +.IR "Current column" : +Set to the last column in which any part of the first character of the +.IR count th +next bigword is displayed. +.SS "Delete Character at Cursor" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR x +.fi +.P +.RE +.RE +.P +Delete the +.IR count +characters at and after the current character into +.IR buffer , +if specified, and into the unnamed buffer. +.P +If the line is empty, it shall be an error. If there are less than +.IR count +non-\c +<newline> +characters at and after the cursor on the current line, +.IR count +shall be adjusted to the number of non-\c +<newline> +characters at and after the cursor. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +If the line is empty, set to column position 1. Otherwise, if there +were +.IR count +or less non-\c +<newline> +characters at and after the cursor on the current line, set to the last +column that displays any part of the last non-\c +<newline> +of the line. Otherwise, unchanged. +.SS "Delete Character Before Cursor" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR X +.fi +.P +.RE +.RE +.P +Delete the +.IR count +characters before the current character into +.IR buffer , +if specified, and into the unnamed buffer. +.P +If there are no characters before the current character on the current +line, it shall be an error. If there are less than +.IR count +previous characters on the current line, +.IR count +shall be adjusted to the number of previous characters on the line. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to (current column \- the width of the deleted characters). +.SS "Yank" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR y \fImotion\fR +.fi +.P +.RE +.RE +.P +Copy (yank) the region of text into +.IR buffer , +if specified, and into the unnamed buffer. +.P +If the motion command is the +.BR y +command repeated: +.IP " 1." 4 +The buffer shall be in line mode. +.IP " 2." 4 +If there are less than +.IR count +\-1 lines after the current line in the edit buffer, it shall be an +error. +.IP " 3." 4 +The text region shall be from the current line up to and including the +next +.IR count +\-1 lines. +.P +Otherwise, the buffer text mode and text region shall be as specified +by the motion command. +.P +.IR "Current line" : +If the motion was from the current cursor position toward the end of +the edit buffer, unchanged. Otherwise, set to the first line in the +edit buffer that is part of the text region specified by the +motion command. +.P +.IR "Current column" : +.IP " 1." 4 +If the motion was from the current cursor position toward the end of +the edit buffer, unchanged. +.IP " 2." 4 +Otherwise, if the current line is empty, set to column position 1. +.IP " 3." 4 +Otherwise, set to the last column that displays any part of the first +character in the file that is part of the text region specified by the +motion command. +.SS "Yank Current Line" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR Y +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR vi +command: +.sp +.RS 4 +.nf + +\fB[\fIbuffer\fB][\fIcount\fB]\fR y_ +.fi +.P +.RE +.SS "Redraw Window" +.P +If in open mode, the +.BR z +command shall have the Synopsis: +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIcount\fB]\fR z +.fi +.P +.RE +.RE +.P +If +.IR count +is not specified, it shall default to the +.BR window +edit option \-1. The +.BR z +command shall be equivalent to the +.IR ex +.BR z +command, with a type character of +.BR = +and a +.IR count +of +.IR count +\-2, except that the current line and current column shall be set as +follows, and the +.BR window +edit option shall not be affected. If the calculation for the +.IR count +argument would result in a negative number, the +.IR count +argument to the +.IR ex +.BR z +command shall be zero. A blank line shall be written after the last +line is written. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Unchanged. +.P +If not in open mode, the +.BR z +command shall have the following Synopsis: +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fB[\fIline\fB]\fR z \fB[\fIcount\fB] \fIcharacter\fR +.fi +.P +.RE +.RE +.P +If +.IR line +is not specified, it shall default to the current line. If +.IR line +is specified, but is greater than the number of lines in the edit +buffer, it shall default to the number of lines in the edit buffer. +.P +If +.IR count +is specified, the value of the +.BR window +edit option shall be set to +.IR count +(as described in the +.IR ex +.BR window +command), and the screen shall be redrawn. +.P +.IR line +shall be placed as specified by the following characters: +.IP "<newline>,\ <carriage-return>" 6 +.br +Place the beginning of the line on the first line of the display. +.IP "\fR.\fP" 6 +Place the beginning of the line in the center of the display. The +middle line of the display shall be calculated as described for the +.BR M +command. +.IP "\fR\-\fP" 6 +Place an unspecified portion of the line on the last line of the +display. +.IP "\fR+\fP" 6 +If +.IR line +was specified, equivalent to the +<newline> +case. If +.IR line +was not specified, display a screen where the first line of the display +shall be (current last line) +1. If there are no lines after the last +line in the display, it shall be an error. +.IP "\fR^\fP" 6 +If +.IR line +was specified, display a screen where the last line of the display +shall contain an unspecified portion of the first line of a display +that had an unspecified portion of the specified line on the last line +of the display. If this calculation results in a line before the +beginning of the edit buffer, display the first screen of the edit +buffer. +.RS 6 +.P +Otherwise, display a screen where the last line of the display shall +contain an unspecified portion of (current first line \-1). If this +calculation results in a line before the beginning of the edit buffer, +it shall be an error. +.RE +.br +.P +.IR "Current line" : +If +.IR line +and the +.BR '\(ha' +character were specified: +.IP " 1." 4 +If the first screen was displayed as a result of the command attempting +to display lines before the beginning of the edit buffer: if the first +screen was already displayed, unchanged; otherwise, set to (current +first line \-1). +.IP " 2." 4 +Otherwise, set to the last line of the display. +.P +If +.IR line +and the +.BR '\(pl' +character were specified, set to the first line of the display. +.P +Otherwise, if +.IR line +was specified, set to +.IR line . +.P +Otherwise, unchanged. +.P +.IR "Current column" : +Set to non-\c +<blank>. +.SS "Exit" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +ZZ +.fi +.P +.RE +.RE +.P +This command shall be equivalent to the +.IR ex +.BR xit +command with no addresses, trailing +.BR ! , +or filename (see the +.IR ex +.BR xit +command). +.SS "Input Mode Commands in vi" +.P +In text input mode, the current line shall consist of zero or more of +the following categories, plus the terminating +<newline>: +.IP " 1." 4 +Characters preceding the text input entry point +.RS 4 +.P +Characters in this category shall not be modified during text input +mode. +.RE +.IP " 2." 4 +.BR autoindent +characters +.RS 4 +.P +.BR autoindent +characters shall be automatically inserted into each line that is +created in text input mode, either as a result of entering a +<newline> +or +<carriage-return> +while in text input mode, or as an effect of the command itself; for +example, +.BR O +or +.BR o +(see the +.IR ex +.BR autoindent +command), as if entered by the user. +.P +It shall be possible to erase +.BR autoindent +characters with the +<control>\(hyD +command; it is unspecified whether they can be erased by +<control>\(hyH, +<control>\(hyU, +and +<control>\(hyW +characters. Erasing any +.BR autoindent +character turns the glyph into erase-columns and deletes the character +from the edit buffer, but does not change its representation on the +screen. +.RE +.IP " 3." 4 +Text input characters +.RS 4 +.P +Text input characters are the characters entered by the user. Erasing +any text input character turns the glyph into erase-columns and deletes +the character from the edit buffer, but does not change its +representation on the screen. +.P +Each text input character entered by the user (that does not have a +special meaning) shall be treated as follows: +.IP " a." 4 +The text input character shall be appended to the last character in the +edit buffer from the first, second, or third categories. +.IP " b." 4 +If there are no erase-columns on the screen, the text input command was +the +.BR R +command, and characters in the fifth category from the original line +follow the cursor, the next such character shall be deleted from the +edit buffer. If the +.BR slowopen +edit option is not set, the corresponding glyph on the screen shall +become erase-columns. +.IP " c." 4 +If there are erase-columns on the screen, as many columns as they +occupy, or as are necessary, shall be overwritten to display the text +input character. (If only part of a multi-column glyph is overwritten, +the remainder shall be left on the screen, and continue to be treated +as erase-columns; it is unspecified whether the remainder of the glyph +is modified in any way.) +.IP " d." 4 +If additional display line columns are needed to display the text input +character: +.RS 4 +.IP " i." 5 +If the +.BR slowopen +edit option is set, the text input characters shall be displayed on +subsequent display line columns, overwriting any characters displayed +in those columns. +.IP ii. 5 +Otherwise, any characters currently displayed on or after the column on +the display line where the text input character is to be displayed +shall be pushed ahead the number of display line columns necessary to +display the rest of the text input character. +.RE +.RE +.IP " 4." 4 +Erase-columns +.RS 4 +.P +Erase-columns are not logically part of the edit buffer, appearing only +on the screen, and may be overwritten on the screen by subsequent text +input characters. When text input mode ends, all erase-columns shall no +longer appear on the screen. +.P +Erase-columns are initially the region of text specified by the +.BR c +command (see +.IR "Change"); +however, erasing +.BR autoindent +or text input characters causes the glyphs of the erased characters to +be treated as erase-columns. +.RE +.IP " 5." 4 +Characters following the text region for the +.BR c +command, or the text input entry point for all other commands +.RS 4 +.P +Characters in this category shall not be modified during text input +mode, except as specified in category 3.b. for the +.BR R +text input command, or as +<blank> +characters deleted when a +<newline> +or +<carriage-return> +is entered. +.RE +.P +It is unspecified whether it is an error to attempt to erase past the +beginning of a line that was created by the entry of a +<newline> +or +<carriage-return> +during text input mode. If it is not an error, the editor shall behave +as if the erasing character was entered immediately after the last text +input character entered on the previous line, and all of the non-\c +<newline> +characters on the current line shall be treated as erase-columns. +.P +When text input mode is entered, or after a text input mode character +is entered (except as specified for the special characters below), the +cursor shall be positioned as follows: +.IP " 1." 4 +On the first column that displays any part of the first erase-column, +if one exists +.IP " 2." 4 +Otherwise, if the +.BR slowopen +edit option is set, on the first display line column after the last +character in the first, second, or third categories, if one exists +.IP " 3." 4 +Otherwise, the first column that displays any part of the first +character in the fifth category, if one exists +.IP " 4." 4 +Otherwise, the display line column after the last character in the +first, second, or third categories, if one exists +.IP " 5." 4 +Otherwise, on column position 1 +.P +The characters that are updated on the screen during text input mode +are unspecified, other than that the last text input character shall +always be updated, and, if the +.BR slowopen +edit option is not set, the current cursor character shall always be +updated. +.P +The following specifications are for command characters entered during +text input mode. +.SS "NUL" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +NUL +.fi +.P +.RE +.RE +.P +If the first character of the text input is a NUL, the most recently +input text shall be input as if entered by the user, and then text +input mode shall be exited. The text shall be input literally; that is, +characters are neither macro or abbreviation expanded, nor are any +characters interpreted in any special manner. It is unspecified whether +implementations shall support more than 256 bytes of remembered input +text. +.SS "<control>-D" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-D +.fi +.P +.RE +.RE +.P +The +<control>\(hyD +character shall have no special meaning when in text input +mode for a line-oriented command (see +.IR "Command Descriptions in vi"). +.P +This command need not be supported on block-mode terminals. +.P +If the cursor does not follow an +.BR autoindent +character, or an +.BR autoindent +character and a +.BR '0' +or +.BR '\(ha' +character: +.IP " 1." 4 +If the cursor is in column position 1, the +<control>\(hyD +character shall be discarded and no further action taken. +.IP " 2." 4 +Otherwise, the +<control>\(hyD +character shall have no special meaning. +.P +If the last input character was a +.BR '0' , +the cursor shall be moved to column position 1. +.P +Otherwise, if the last input character was a +.BR '\(ha' , +the cursor shall be moved to column position 1. In addition, the +.BR autoindent +level for the next input line shall be derived from the same line from +which the +.BR autoindent +level for the current input line was derived. +.P +Otherwise, the cursor shall be moved back to the column after the +previous shiftwidth (see the +.IR ex +.BR shiftwidth +command) boundary. +.P +All of the glyphs on columns between the starting cursor position and +(inclusively) the ending cursor position shall become erase-columns as +described in +.IR "Input Mode Commands in vi". +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to 1 if the +<control>\(hyD +was preceded by a +.BR '\(ha' +or +.BR '0' ; +otherwise, set to (column \-1) \-((column \-2) % +.BR shiftwidth ). +.SS "<control>-H" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-H +.fi +.P +.RE +.RE +.P +If in text input mode for a line-oriented command, and there are no +characters to erase, text input mode shall be terminated, no further +action shall be done for this command, and the current line and column +shall be unchanged. +.P +If there are characters other than +.BR autoindent +characters that have been input on the current line before the cursor, +the cursor shall move back one character. +.P +Otherwise, if there are +.BR autoindent +characters on the current line before the cursor, it is +implementation-defined whether the +<control>\(hyH +command is an error or if the cursor moves back one +.BR autoindent +character. +.P +Otherwise, if the cursor is in column position 1 and there are previous +lines that have been input, it is implementation-defined whether the +<control>\(hyH +command is an error or if it is equivalent to entering +<control>\(hyH +after the last input character on the previous input line. +.P +Otherwise, it shall be an error. +.P +All of the glyphs on columns between the starting cursor position and +(inclusively) the ending cursor position shall become erase-columns as +described in +.IR "Input Mode Commands in vi". +.P +The current erase character (see +.IR stty ) +shall cause an equivalent action to the +<control>\(hyH +command, unless the previously inserted character was a +<backslash>, +in which case it shall be as if the literal current erase character had +been inserted instead of the +<backslash>. +.P +.IR "Current line" : +Unchanged, unless previously input lines are erased, in which case it +shall be set to line \-1. +.P +.IR "Current column" : +Set to the first column that displays any portion of the character +backed up over. +.SS "<newline>" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<newline> +.br +<carriage-return> +.br +<control>-J +.br +<control>-M +.fi +.P +.RE +.RE +.P +If input was part of a line-oriented command, text input mode shall be +terminated and the command shall continue execution with the input +provided. +.P +Otherwise, terminate the current line. If there are no characters other +than +.BR autoindent +characters on the line, all characters on the line shall be discarded. +Otherwise, it is unspecified whether the +.BR autoindent +characters in the line are modified by entering these characters. +.P +Continue text input mode on a new line appended after the current line. +If the +.BR slowopen +edit option is set, the lines on the screen below the current line +shall not be pushed down, but the first of them shall be cleared and +shall appear to be overwritten. Otherwise, the lines of the screen +below the current line shall be pushed down. +.P +If the +.BR autoindent +edit option is set, an appropriate number of +.BR autoindent +characters shall be added as a prefix to the line as described by the +.IR ex +.BR autoindent +edit option. +.P +All columns after the cursor that are erase-columns (as described in +.IR "Input Mode Commands in vi") +shall be discarded. +.P +If the +.BR autoindent +edit option is set, all +<blank> +characters immediately following the cursor shall be discarded. +.P +All remaining characters after the cursor shall be transferred to the +new line, positioned after any +.BR autoindent +characters. +.P +.IR "Current line" : +Set to current line +1. +.P +.IR "Current column" : +Set to the first column that displays any portion of the first +character after the +.BR autoindent +characters on the new line, if any, or the first column position after +the last +.BR autoindent +character, if any, or column position 1. +.SS "<control>-T" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-T +.fi +.P +.RE +.RE +.P +The +<control>\(hyT +character shall have no special meaning when in text input mode for a +line-oriented command (see +.IR "Command Descriptions in vi"). +.P +This command need not be supported on block-mode terminals. +.P +Behave as if the user entered the minimum number of +<blank> +characters necessary to move the cursor forward to the column position +after the next +.BR shiftwidth +(see the +.IR ex +.BR shiftwidth +command) boundary. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Set to +.IR column ++ +.BR shiftwidth +\- ((column \-1) % +.BR shiftwidth ). +.SS "<control>-U" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-U +.fi +.P +.RE +.RE +.P +If there are characters other than +.BR autoindent +characters that have been input on the current line before the cursor, +the cursor shall move to the first character input after the +.BR autoindent +characters. +.P +Otherwise, if there are +.BR autoindent +characters on the current line before the cursor, it is +implementation-defined whether the +<control>\(hyU +command is an error or if the cursor moves to the first column position +on the line. +.P +Otherwise, if the cursor is in column position 1 and there are previous +lines that have been input, it is implementation-defined whether the +<control>\(hyU +command is an error or if it is equivalent to entering +<control>\(hyU +after the last input character on the previous input line. +.P +Otherwise, it shall be an error. +.P +All of the glyphs on columns between the starting cursor position and +(inclusively) the ending cursor position shall become erase-columns as +described in +.IR "Input Mode Commands in vi". +.P +The current +.IR kill +character (see +.IR stty ) +shall cause an equivalent action to the +<control>\(hyU +command, unless the previously inserted character was a +<backslash>, +in which case it shall be as if the literal current +.IR kill +character had been inserted instead of the +<backslash>. +.P +.IR "Current line" : +Unchanged, unless previously input lines are erased, in which case it +shall be set to line \-1. +.P +.IR "Current column" : +Set to the first column that displays any portion of the last character +backed up over. +.SS "<control>-V" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-V +.br +<control>-Q +.fi +.P +.RE +.RE +.P +Allow the entry of any subsequent character, other than +<control>\(hyJ +or the +<newline>, +as a literal character, removing any special meaning that it may have +to the editor in text input mode. If a +<control>\(hyV +or +<control>\(hyQ +is entered before a +<control>\(hyJ +or +<newline>, +the +<control>\(hyV +or +<control>\(hyQ +character shall be discarded, and the +<control>\(hyJ +or +<newline> +shall behave as described in the +<newline> +command character during input mode. +.P +For purposes of the display only, the editor shall behave as if a +.BR '\(ha' +character was entered, and the cursor shall be positioned as if +overwriting the +.BR '\(ha' +character. When a subsequent character is entered, the editor shall +behave as if that character was entered instead of the original +<control>\(hyV +or +<control>\(hyQ +character. +.P +.IR "Current line" : +Unchanged. +.P +.IR "Current column" : +Unchanged. +.SS "<control>-W" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<control>-W +.fi +.P +.RE +.RE +.P +If there are characters other than +.BR autoindent +characters that have been input on the current line before the cursor, +the cursor shall move back over the last word preceding the cursor +(including any +<blank> +characters between the end of the last word and the current cursor); the +cursor shall not move to before the first character after the end of any +.BR autoindent +characters. +.P +Otherwise, if there are +.BR autoindent +characters on the current line before the cursor, it is +implementation-defined whether the +<control>\(hyW +command is an error or if the cursor moves to the first column position +on the line. +.P +Otherwise, if the cursor is in column position 1 and there are previous +lines that have been input, it is implementation-defined whether the +<control>\(hyW +command is an error or if it is equivalent to entering +<control>\(hyW +after the last input character on the previous input line. +.P +Otherwise, it shall be an error. +.P +All of the glyphs on columns between the starting cursor position and +(inclusively) the ending cursor position shall become erase-columns as +described in +.IR "Input Mode Commands in vi". +.P +.IR "Current line" : +Unchanged, unless previously input lines are erased, in which case it +shall be set to line \-1. +.P +.IR "Current column" : +Set to the first column that displays any portion of the last character +backed up over. +.SS "<ESC>" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +<ESC> +.fi +.P +.RE +.RE +.P +If input was part of a line-oriented command: +.IP " 1." 4 +If +.IR interrupt +was entered, text input mode shall be terminated and the editor shall +return to command mode. The terminal shall be alerted. +.IP " 2." 4 +If +<ESC> +was entered, text input mode shall be terminated and the command shall +continue execution with the input provided. +.P +Otherwise, terminate text input mode and return to command mode. +.P +Any +.BR autoindent +characters entered on newly created lines that have no other non-\c +<newline> +characters shall be deleted. +.P +Any leading +.BR autoindent +and +<blank> +characters on newly created lines shall be rewritten to be the minimum +number of +<blank> +characters possible. +.P +The screen shall be redisplayed as necessary to match the contents of +the edit buffer. +.P +.IR "Current line" : +Unchanged. +.br +.P +.IR "Current column" : +.IP " 1." 4 +If there are text input characters on the current line, the column +shall be set to the last column where any portion of the last text +input character is displayed. +.IP " 2." 4 +Otherwise, if a character is displayed in the current column, +unchanged. +.IP " 3." 4 +Otherwise, set to column position 1. +.SH "EXIT STATUS" +The following exit values shall be returned: +.IP "\00" 6 +Successful completion. +.IP >0 6 +An error occurred. +.SH "CONSEQUENCES OF ERRORS" +When any error is encountered and the standard input is not a terminal +device file, +.IR vi +shall not write the file or return to command or text input mode, and +shall terminate with a non-zero exit status. +.P +Otherwise, when an unrecoverable error is encountered it shall be +equivalent to a SIGHUP asynchronous event. +.P +Otherwise, when an error is encountered, the editor shall behave as +specified in +.IR "Command Descriptions in vi". +.LP +.IR "The following sections are informative." +.SH "APPLICATION USAGE" +None. +.SH EXAMPLES +None. +.SH RATIONALE +See the RATIONALE for +.IR "\fIex\fR\^" +for more information on +.IR vi . +Major portions of the +.IR vi +utility specification point to +.IR ex +to avoid inadvertent divergence. While +.IR ex +and +.IR vi +have historically been implemented as a single utility, this is not +required by POSIX.1\(hy2008. +.P +It is recognized that portions of +.IR vi +would be difficult, if not impossible, to implement satisfactorily on a +block-mode terminal, or a terminal without any form of cursor +addressing, thus it is not a mandatory requirement that such features +should work on all terminals. It is the intention, however, that a +.IR vi +implementation should provide the full set of capabilities on all +terminals capable of supporting them. +.P +Historically, +.IR vi +exited immediately if the standard input was not a terminal. POSIX.1\(hy2008 +permits, but does not require, this behavior. An end-of-file condition +is not equivalent to an end-of-file character. A common end-of-file +character, +<control>\(hyD, +is historically a +.IR vi +command. +.P +The text in the STDOUT section reflects the usage of the verb +.IR display +in this section; some implementations of +.IR vi +use standard output to write to the terminal, but POSIX.1\(hy2008 does not +require that to be the case. +.P +Historically, implementations reverted to open mode if the terminal was +incapable of supporting full visual mode. POSIX.1\(hy2008 requires this +behavior. Historically, the open mode of +.IR vi +behaved roughly equivalently to the visual mode, with the exception +that only a single line from the edit buffer (one ``buffer line'') was +kept current at any time. This line was normally displayed on the +next-to-last line of a terminal with cursor addressing (and the last +line performed its normal visual functions for line-oriented commands +and messages). In addition, some few commands behaved differently in +open mode than in visual mode. POSIX.1\(hy2008 requires conformance to historical +practice. +.P +Historically, +.IR ex +and +.IR vi +implementations have expected text to proceed in the usual +European/Latin order of left to right, top to bottom. There is no +requirement in POSIX.1\(hy2008 that this be the case. The specification was +deliberately written using words like ``before'', ``after'', ``first'', +and ``last'' in order to permit implementations to support the natural +text order of the language. +.P +Historically, lines past the end of the edit buffer were marked with +single +<tilde> +(\c +.BR '\(ti' ) +characters; that is, if the one-based display was 20 lines in length, +and the last line of the file was on line one, then lines 2-20 would +contain only a single +.BR '\(ti' +character. +.P +Historically, the +.IR vi +editor attempted to display only complete lines at the bottom of the +screen (it did display partial lines at the top of the screen). If a +line was too long to fit in its entirety at the bottom of the screen, +the screen lines where the line would have been displayed were +displayed as single +.BR '@' +characters, instead of displaying part of the line. POSIX.1\(hy2008 permits, but +does not require, this behavior. Implementations are encouraged to +attempt always to display a complete line at the bottom of the screen +when doing scrolling or screen positioning by buffer lines. +.P +Historically, lines marked with +.BR '@' +were also used to minimize output to dumb terminals over slow lines; +that is, changes local to the cursor were updated, but changes to lines +on the screen that were not close to the cursor were simply marked with +an +.BR '@' +sign instead of being updated to match the current text. POSIX.1\(hy2008 permits, +but does not require this feature because it is used ever less +frequently as terminals become smarter and connections are faster. +.SS "Initialization in ex and vi" +.P +Historically, +.IR vi +always had a line in the edit buffer, even if the edit buffer was +``empty''. For example: +.IP " 1." 4 +The +.IR ex +command +.BR = +executed from visual mode wrote ``1'' when the buffer was empty. +.IP " 2." 4 +Writes from visual mode of an empty edit buffer wrote files of a single +character (a +<newline>), +while writes from +.IR ex +mode of an empty edit buffer wrote empty files. +.IP " 3." 4 +Put and read commands into an empty edit buffer left an empty line at +the top of the edit buffer. +.P +For consistency, POSIX.1\(hy2008 does not permit any of these behaviors. +.P +Historically, +.IR vi +did not always return the terminal to its original modes; for example, +ICRNL was modified if it was not originally set. POSIX.1\(hy2008 does not permit +this behavior. +.SS "Command Descriptions in vi" +.P +Motion commands are among the most complicated aspects of +.IR vi +to describe. With some exceptions, the text region and buffer type +effect of a motion command on a +.IR vi +command are described on a case-by-case basis. The descriptions of text +regions in POSIX.1\(hy2008 are not intended to imply direction; that is, an +inclusive region from line +.IR n +to line +.IR n +5 +is identical to a region from line +.IR n +5 +to line +.IR n . +This is of more than academic interest\(emmovements to marks can be in +either direction, and, if the +.BR wrapscan +option is set, so can movements to search points. Historically, lines +are always stored into buffers in text order; that is, from the start +of the edit buffer to the end. POSIX.1\(hy2008 requires conformance to historical +practice. +.P +Historically, command counts were applied to any associated motion, and +were multiplicative to any supplied motion count. For example, +.BR 2cw +is the same as +.BR c2w , +and +.BR 2c3w +is the same as +.BR c6w . +POSIX.1\(hy2008 requires this behavior. Historically, +.IR vi +commands that used bigwords, words, paragraphs, and sentences as +objects treated groups of empty lines, or lines that contained only +<blank> +characters, inconsistently. Some commands treated them as a single entity, +while others treated each line separately. For example, the +.BR w , +.BR W , +and +.BR B +commands treated groups of empty lines as individual words; that is, +the command would move the cursor to each new empty line. The +.BR e +and +.BR E +commands treated groups of empty lines as a single word; that is, the +first use would move past the group of lines. The +.BR b +command would just beep at the user, or if done from the start of the +line as a motion command, fail in unexpected ways. If the lines +contained only (or ended with) +<blank> +characters, the +.BR w +and +.BR W +commands would just beep at the user, the +.BR E +and +.BR e +commands would treat the group as a single word, and the +.BR B +and +.BR b +commands would treat the lines as individual words. For consistency and +simplicity of specification, POSIX.1\(hy2008 requires that all +.IR vi +commands treat groups of empty or blank lines as a single entity, and +that movement through lines ending with +<blank> +characters be consistent with other movements. +.P +Historically, +.IR vi +documentation indicated that any number of double-quotes were skipped +after punctuation marks at sentence boundaries; however, +implementations only skipped single-quotes. POSIX.1\(hy2008 requires both to be +skipped. +.P +Historically, the first and last characters in the edit buffer were +word boundaries. This historical practice is required by POSIX.1\(hy2008. +.P +Historically, +.IR vi +attempted to update the minimum number of columns on the screen +possible, which could lead to misleading information being displayed. +POSIX.1\(hy2008 makes no requirements other than that the current character being +entered is displayed correctly, leaving all other decisions in this +area up to the implementation. +.P +Historically, lines were arbitrarily folded between columns of any +characters that required multiple column positions on the screen, with +the exception of tabs, which terminated at the right-hand margin. POSIX.1\(hy2008 +permits the former and requires the latter. Implementations that do not +arbitrarily break lines between columns of characters that occupy +multiple column positions should not permit the cursor to rest on a +column that does not contain any part of a character. +.P +The historical +.IR vi +had a problem in that all movements were by buffer lines, not by +display or screen lines. This is often the right thing to do; for +example, single line movements, such as +.BR j +or +.BR k , +should work on buffer lines. Commands like +.BR dj , +or +.BR j. , +where +.BR . +is a change command, only make sense for buffer lines. It is not, +however, the right thing to do for screen motion or scrolling commands +like +<control>\(hyD, +<control>\(hyF, +and +.BR H . +If the window is fairly small, using buffer lines in these cases can +result in completely random motion; for example, +.BR 1 \c +<control>\c +.BR \(hyD +can result in a completely changed screen, without any overlap. This is +clearly not what the user wanted. The problem is even worse in the case +of the +.BR H , +.BR L , +and +.BR M +commands\(emas they position the cursor at the first non-\c +<blank> +of the line, they may all refer to the same location in large lines, +and will result in no movement at all. +.P +In addition, if the line is larger than the screen, using buffer +lines can make it impossible to display parts of the line\(emthere are +not any commands that do not display the beginning of the line in +historical +.IR vi , +and if both the beginning and end of the line cannot be on the screen +at the same time, the user suffers. Finally, the page and half-page +scrolling commands historically moved to the first non-\c +<blank> +in the new line. If the line is approximately the same size as the +screen, this is inadequate because the cursor before and after a +<control>\(hyD +command will refer to the same location on the screen. +.P +Implementations of +.IR ex +and +.IR vi +exist that do not have these problems because the relevant commands (\c +<control>\(hyB, +<control>\(hyD, +<control>\(hyF, +<control>\(hyU, +<control>\(hyY, +<control>\(hyE, +.BR H , +.BR L , +and +.BR M) +operate on display (screen) lines, not (edit) buffer lines. +.P +POSIX.1\(hy2008 does not permit this behavior by default because the standard +developers believed that users would find it too confusing. However, +historical practice has been relaxed. For example, +.IR ex +and +.IR vi +historically attempted, albeit sometimes unsuccessfully, to never put +part of a line on the last lines of a screen; for example, if a line +would not fit in its entirety, no part of the line was displayed, and +the screen lines corresponding to the line contained single +.BR '@' +characters. This behavior is permitted, but not required by POSIX.1\(hy2008, so +that it is possible for implementations to support long lines in small +screens more reasonably without changing the commands to be oriented to +the display (instead of oriented to the buffer). POSIX.1\(hy2008 also permits +implementations to refuse to edit any edit buffer containing a line +that will not fit on the screen in its entirety. +.P +The display area (for example, the value of the +.BR window +edit option) has historically been ``grown'', or expanded, to display +new text when local movements are done in displays where the number of +lines displayed is less than the maximum possible. Expansion has +historically been the first choice, when the target line is less than +the maximum possible expansion value away. Scrolling has historically +been the next choice, done when the target line is less than half a +display away, and otherwise, the screen was redrawn. There were +exceptions, however, in that +.IR ex +commands generally always caused the screen to be redrawn. POSIX.1\(hy2008 does +not specify a standard behavior because there may be external issues, +such as connection speed, the number of characters necessary to redraw +as opposed to scroll, or terminal capabilities that implementations +will have to accommodate. +.P +The current line in POSIX.1\(hy2008 maps one-to-one to a buffer line in the +file. The current column does not. There are two different column +values that are described by POSIX.1\(hy2008. The first is the current column +value as set by many of the +.IR vi +commands. This value is remembered for the lifetime of the editor. The +second column value is the actual position on the screen where the +cursor rests. The two are not always the same. For example, when the +cursor is backed by a multi-column character, the actual cursor +position on the screen has historically been the last column of the +character in command mode, and the first column of the character in +input mode. +.P +Commands that set the current line, but that do not set the current +cursor value (for example, +.BR j +and +.BR k ) +attempt to get as close as possible to the remembered column position, +so that the cursor tends to restrict itself to a vertical column as the +user moves around in the edit buffer. POSIX.1\(hy2008 requires conformance to +historical practice, requiring that the display location of the cursor +on the display line be adjusted from the current column value as +necessary to support this historical behavior. +.P +Historically, only a single line (and for some terminals, a single line +minus 1 column) of characters could be entered by the user for the +line-oriented commands; that is, +.BR : , +.BR ! , +.BR / , +or +.BR ? . +POSIX.1\(hy2008 permits, but does not require, this limitation. +.P +Historically, ``soft'' errors in +.IR vi +caused the terminal to be alerted, but no error message was displayed. +As a general rule, no error message was displayed for errors in command +execution in +.IR vi , +when the error resulted from the user attempting an invalid or +impossible action, or when a searched-for object was not found. +Examples of soft errors included +.BR h +at the left margin, +<control>\(hyB +or +.BR [[ +at the beginning of the file, +.BR 2G +at the end of the file, and so on. In addition, errors such as +.BR % , +.BR ]] , +.BR } , +.BR ) , +.BR N , +.BR n , +.BR f , +.BR F , +.BR t , +and +.BR T +failing to find the searched-for object were soft as well. Less +consistently, +.BR / +and +.BR ? +displayed an error message if the pattern was not found, +.BR / , +.BR ? , +.BR N , +and +.BR n +displayed an error message if no previous regular expression had been +specified, and +.BR ; +did not display an error message if no previous +.BR f , +.BR F , +.BR t , +or +.BR T +command had occurred. Also, behavior in this area might reasonably be +based on a runtime evaluation of the speed of a network connection. +Finally, some implementations have provided error messages for soft +errors in order to assist naive users, based on the value of a verbose +edit option. POSIX.1\(hy2008 does not list specific errors for which an error +message shall be displayed. Implementations should conform to +historical practice in the absence of any strong reason to diverge. +.SS "Page Backwards" +.P +The +<control>\(hyB +and +<control>\(hyF +commands historically considered it an error to attempt to page past +the beginning or end of the file, whereas the +<control>\(hyD +and +<control>\(hyU +commands simply moved to the beginning or end of the file. For +consistency, POSIX.1\(hy2008 requires the latter behavior for all four commands. +All four commands still consider it an error if the current line is at +the beginning (\c +<control>\(hyB, +<control>\(hyU) +or end (\c +<control>\(hyF, +<control>\(hyD) +of the file. Historically, the +<control>\(hyB +and +<control>\(hyF +commands skip two lines in order to include overlapping lines when a +single command is entered. This makes less sense in the presence of a +.IR count , +as there will be, by definition, no overlapping lines. The actual +calculation used by historical implementations of the +.IR vi +editor for +<control>\(hyB +was: +.sp +.RS 4 +.nf + +((current first line) - count x (window edit option)) +2 +.fi +.P +.RE +.P +and for +<control>\(hyF +was: +.sp +.RS 4 +.nf + +((current first line) + count x (window edit option)) -2 +.fi +.P +.RE +.P +This calculation does not work well when intermixing commands with and +without counts; for example, +.BR 3\c +<control>\(hyF +is not equivalent to entering the +<control>\(hyF +command three times, and is not reversible by entering the +<control>\(hyB +command three times. For consistency with other +.IR vi +commands that take counts, POSIX.1\(hy2008 requires a different calculation. +.SS "Scroll Forward" +.P +The 4BSD and System V implementations of +.IR vi +differed on the initial value used by the +.BR scroll +command. 4BSD used: +.sp +.RS 4 +.nf + +((window edit option) +1) /2 +.fi +.P +.RE +.P +while System V used the value of the +.BR scroll +edit option. The System V version is specified by POSIX.1\(hy2008 because the +standard developers believed that it was more intuitive and permitted +the user a method of setting the scroll value initially without also +setting the number of lines that are displayed. +.SS "Scroll Forward by Line" +.P +Historically, the +<control>\(hyE +and +<control>\(hyY +commands considered it an error if the last and first lines, +respectively, were already on the screen. POSIX.1\(hy2008 requires conformance to +historical practice. Historically, the +<control>\(hyE +and +<control>\(hyY +commands had no effect in open mode. For simplicity and consistency of +specification, POSIX.1\(hy2008 requires that they behave as usual, albeit with a +single line screen. +.SS "Clear and Redisplay" +.P +The historical +<control>\(hyL +command refreshed the screen exactly as it was supposed to be currently +displayed, replacing any +.BR '@' +characters for lines that had been deleted but not updated on the +screen with refreshed +.BR '@' +characters. The intent of the +<control>\(hyL +command is to refresh when the screen has been accidentally +overwritten; for example, by a +.BR write +command from another user, or modem noise. +.SS "Redraw Screen" +.P +The historical +<control>\(hyR +command redisplayed only when necessary to update lines that had been +deleted but not updated on the screen and that were flagged with +.BR '@' +characters. There is no requirement that the screen be in any way +refreshed if no lines of this form are currently displayed. POSIX.1\(hy2008 +permits implementations to extend this command to refresh lines on the +screen flagged with +.BR '@' +characters because they are too long to be displayed in the current +framework; however, the current line and column need not be modified. +.SS "Search for tagstring" +.P +Historically, the first non-\c +<blank> +at or after the cursor was the first character, and all subsequent +characters that were word characters, up to the end of the line, were +included. For example, with the cursor on the leading +<space> +or on the +.BR '#' +character in the text +.BR \(dq#bar@\(dq , +the tag was +.BR \(dq#bar\(dq . +On the character +.BR 'b' +it was +.BR \(dqbar\(dq , +and on the +.BR 'a' +it was +.BR \(dqar\(dq . +POSIX.1\(hy2008 requires this behavior. +.SS "Replace Text with Results from Shell Command" +.P +Historically, the +.BR < , +.BR > , +and +.BR ! +commands considered most cursor motions other than line-oriented +motions an error; for example, the command +.BR ">/foo<CR>" +succeeded, while the command +.BR ">l" +failed, even though the text region described by the two commands might +be identical. For consistency, all three commands only consider entire +lines and not partial lines, and the region is defined as any line that +contains a character that was specified by the motion. +.SS "Move to Matching Character" +.P +Other matching characters have been left implementation-defined in +order to allow extensions such as matching +.BR '<' +and +.BR '>' +for searching HTML, or +.BR #ifdef , +.BR #else , +and +.BR #endif +for searching C source. +.SS "Repeat Substitution" +.P +POSIX.1\(hy2008 requires that any +.BR c +and +.BR g +flags specified to the previous substitute command be ignored; however, +the +.BR r +flag may still apply, if supported by the implementation. +.SS "Return to Previous (Context or Section)" +.P +The +.BR [[ , +.BR ]] , +.BR ( , +.BR ) , +.BR { , +and +.BR } +commands are all affected by ``section boundaries'', but in some +historical implementations not all of the commands recognize the same +section boundaries. This is a bug, not a feature, and a unique +section-boundary algorithm was not described for each command. One +special case that is preserved is that the sentence command moves to +the end of the last line of the edit buffer while the other commands go +to the beginning, in order to preserve the traditional character cut +semantics of the sentence command. Historically, +.IR vi +section boundaries at the beginning and end of the edit buffer were the +first non-\c +<blank> +on the first and last lines of the edit buffer if one exists; +otherwise, the last character of the first and last lines of the edit +buffer if one exists. To increase consistency with other section +locations, this has been simplified by POSIX.1\(hy2008 to the first character of +the first and last lines of the edit buffer, or the first and the last +lines of the edit buffer if they are empty. +.P +Sentence boundaries were problematic in the historical +.IR vi . +They were not only the boundaries as defined for the section and +paragraph commands, but they were the first non-\c +<blank> +that occurred after those boundaries, as well. Historically, the +.IR vi +section commands were documented as taking an optional window size as a +.IR count +preceding the command. This was not implemented in historical versions, +so POSIX.1\(hy2008 requires that the +.IR count +repeat the command, for consistency with other +.IR vi +commands. +.SS "Repeat" +.P +Historically, mapped commands other than text input commands could not +be repeated using the +.BR period +command. POSIX.1\(hy2008 requires conformance to historical practice. +.P +The restrictions on the interpretation of special characters (for +example, +<control>\(hyH) +in the repetition of text input mode commands is intended to match +historical practice. For example, given the input sequence: +.sp +.RS 4 +.nf + +iab<control>-H<control>-H<control>-Hdef<escape> +.fi +.P +.RE +.P +the user should be informed of an error when the sequence is first +entered, but not during a command repetition. The character +<control>\(hyT +is specifically exempted from this restriction. Historical +implementations of +.IR vi +ignored +<control>\(hyT +characters that were input in the original command during command +repetition. POSIX.1\(hy2008 prohibits this behavior. +.SS "Find Regular Expression" +.P +Historically, commands did not affect the line searched to or from if +the motion command was a search (\c +.BR / , +.BR ? , +.BR N , +.BR n ) +and the final position was the start/end of the line. There were some +special cases and +.IR vi +was not consistent. POSIX.1\(hy2008 does not permit this behavior, for +consistency. Historical implementations permitted but were unable to +handle searches as motion commands that wrapped (that is, due to the +edit option +.BR wrapscan ) +to the original location. POSIX.1\(hy2008 requires that this behavior be treated +as an error. +.P +Historically, the syntax +.BR \(dq/RE/0\(dq +was used to force the command to cut text in line mode. POSIX.1\(hy2008 requires +conformance to historical practice. +.P +Historically, in open mode, a +.BR z +specified to a search command redisplayed the current line instead of +displaying the current screen with the current line highlighted. For +consistency and simplicity of specification, POSIX.1\(hy2008 does not permit this +behavior. +.P +Historically, trailing +.BR z +commands were permitted and ignored if entered as part of a search used +as a motion command. For consistency and simplicity of specification, +POSIX.1\(hy2008 does not permit this behavior. +.SS "Execute an ex Command" +.P +Historically, +.IR vi +implementations restricted the commands that could be entered on the +colon command line (for example, +.BR append +and +.BR change ), +and some other commands were known to cause them to fail +catastrophically. For consistency, POSIX.1\(hy2008 does not permit these +restrictions. When executing an +.IR ex +command by entering +.BR : , +it is not possible to enter a +<newline> +as part of the command because it is considered the end of the command. +A different approach is to enter +.IR ex +command mode by using the +.IR vi +.BR Q +command (and later resuming visual mode with the +.IR ex +.BR vi +command). In +.IR ex +command mode, the single-line limitation does not exist. So, for +example, the following is valid: +.sp +.RS 4 +.nf + +Q +s/break here/break\e +here/ +vi +.fi +.P +.RE +.P +POSIX.1\(hy2008 requires that, if the +.IR ex +command overwrites any part of the screen that would be erased by a +refresh, +.IR vi +pauses for a character from the user. Historically, this character +could be any character; for example, a character input by the user +before the message appeared, or even a mapped character. This is +probably a bug, but implementations that have tried to be more rigorous +by requiring that the user enter a specific character, or that the user +enter a character after the message was displayed, have been forced by +user indignation back into historical behavior. POSIX.1\(hy2008 requires +conformance to historical practice. +.SS "Shift Left (Right)" +.P +Refer to the Rationale for the +.BR ! +and +.BR / +commands. Historically, the +.BR < +and +.BR > +commands sometimes moved the cursor to the first non-\c +<blank> +(for example if the command was repeated or with +.BR _ +as the motion command), and sometimes left it unchanged. POSIX.1\(hy2008 does not +permit this inconsistency, requiring instead that the cursor always +move to the first non-\c +<blank>. +Historically, the +.BR < +and +.BR > +commands did not support buffer arguments, although some +implementations allow the specification of an optional buffer. This +behavior is neither required nor disallowed by POSIX.1\(hy2008. +.SS "Execute" +.P +Historically, buffers could execute other buffers, and loops, infinite +and otherwise, were possible. POSIX.1\(hy2008 requires conformance to historical +practice. The *\c +.IR buffer +syntax of +.IR ex +is not required in +.IR vi , +because it is not historical practice and has been used in some +.IR vi +implementations to support additional scripting languages. +.SS "Reverse Case" +.P +Historically, the +.BR ~ +command ignored any associated +.IR count , +and acted only on the characters in the current line. For consistency +with other +.IR vi +commands, POSIX.1\(hy2008 requires that an associated +.IR count +act on the next +.IR count +characters, and that the command move to subsequent lines if warranted +by +.IR count , +to make it possible to modify large pieces of text in a reasonably +efficient manner. There exist +.IR vi +implementations that optionally require an associated motion command +for the +.BR ~ +command. Implementations supporting this functionality are encouraged +to base it on the +.BR tildedop +edit option and handle the text regions and cursor positioning +identically to the +.BR yank +command. +.SS "Append" +.P +Historically, +.IR count s +specified to the +.BR A , +.BR a , +.BR I , +and +.BR i +commands repeated the input of the first line +.IR count +times, and did not repeat the subsequent lines of the input text. POSIX.1\(hy2008 +requires that the entire text input be repeated +.IR count +times. +.SS "Move Backward to Preceding Word" +.P +Historically, +.IR vi +became confused if word commands were used as motion commands in empty +files. POSIX.1\(hy2008 requires that this be an error. Historical implementations +of +.IR vi +had a large number of bugs in the word movement commands, and they +varied greatly in behavior in the presence of empty lines, ``words'' +made up of a single character, and lines containing only +<blank> +characters. For consistency and simplicity of specification, POSIX.1\(hy2008 does +not permit this behavior. +.SS "Change to End-of-Line" +.P +Some historical implementations of the +.BR C +command did not behave as described by POSIX.1\(hy2008 when the +.BR $ +key was remapped because they were implemented by pushing the +.BR $ +key onto the input queue and reprocessing it. POSIX.1\(hy2008 does not permit +this behavior. Historically, the +.BR C , +.BR S , +and +.BR s +commands did not copy replaced text into the numeric buffers. For +consistency and simplicity of specification, POSIX.1\(hy2008 requires that they +behave like their respective +.BR c +commands in all respects. +.SS "Delete" +.P +Historically, lines in open mode that were deleted were scrolled up, +and an +.BR @ +glyph written over the beginning of the line. In the case of terminals +that are incapable of the necessary cursor motions, the editor erased +the deleted line from the screen. POSIX.1\(hy2008 requires conformance to +historical practice; that is, if the terminal cannot display the +.BR '@' +character, the line cannot remain on the screen. +.SS "Delete to End-of-Line" +.P +Some historical implementations of the +.BR D +command did not behave as described by POSIX.1\(hy2008 when the +.BR $ +key was remapped because they were implemented by pushing the +.BR $ +key onto the input queue and reprocessing it. POSIX.1\(hy2008 does not permit +this behavior. +.SS "Join" +.P +An historical oddity of +.IR vi +is that the commands +.BR J , +.BR 1J , +and +.BR 2J +are all equivalent. POSIX.1\(hy2008 requires conformance to historical practice. +The +.IR vi +.BR J +command is specified in terms of the +.IR ex +.BR join +command with an +.IR ex +command +.IR count +value. The address correction for a +.IR count +that is past the end of the edit buffer is necessary for historical +compatibility for both +.IR ex +and +.IR vi . +.SS "Mark Position" +.P +Historical practice is that only lowercase letters, plus backquote and +single-quote, could be used to mark a cursor position. POSIX.1\(hy2008 requires +conformance to historical practice, but encourages implementations to +support other characters as marks as well. +.SS "Repeat Regular Expression Find (Forward and Reverse)" +.P +Historically, the +.BR N +and +.BR n +commands could not be used as motion components for the +.BR c +command. With the exception of the +.BR cN +command, which worked if the search crossed a line boundary, the text +region would be discarded, and the user would not be in text input +mode. For consistency and simplicity of specification, POSIX.1\(hy2008 does not +permit this behavior. +.SS "Insert Empty Line (Below and Above)" +.P +Historically, counts to the +.BR O +and +.BR o +commands were used as the number of physical lines to open, if the +terminal was dumb and the +.BR slowopen +option was not set. This was intended to minimize traffic over slow +connections and repainting for dumb terminals. POSIX.1\(hy2008 does not permit +this behavior, requiring that a +.IR count +to the open command behave as for other text input commands. This +change to historical practice was made for consistency, and because a +superset of the functionality is provided by the +.BR slowopen +edit option. +.SS "Put from Buffer (Following and Before)" +.P +Historically, +.IR count s +to the +.BR p +and +.BR P +commands were ignored if the buffer was a line mode buffer, but were +(mostly) implemented as described in POSIX.1\(hy2008 if the buffer was a +character mode buffer. Because implementations exist that do not have +this limitation, and because pasting lines multiple times is generally +useful, POSIX.1\(hy2008 requires that +.IR count +be supported for all +.BR p +and +.BR P +commands. +.P +Historical implementations of +.IR vi +were widely known to have major problems in the +.BR p +and +.BR P +commands, particularly when unusual regions of text were copied into +the edit buffer. The standard developers viewed these as bugs, and they +are not permitted for consistency and simplicity of specification. +.P +Historically, a +.BR P +or +.BR p +command (or an +.IR ex +.BR put +command executed from open or visual mode) executed in an empty file, +left an empty line as the first line of the file. For consistency and +simplicity of specification, POSIX.1\(hy2008 does not permit this behavior. +.SS "Replace Character" +.P +Historically, the +.BR r +command did not correctly handle the +.IR erase +and +.IR "word erase" +characters as arguments, nor did it handle an associated +.IR count +greater than 1 with a +<carriage-return> +argument, for which it replaced +.IR count +characters with a single +<newline>. +POSIX.1\(hy2008 does not permit these inconsistencies. +.P +Historically, the +.BR r +command permitted the +<control>\(hyV +escaping of entered characters, such as +<ESC> +and the +<carriage-return>; +however, it required two leading +<control>\(hyV +characters instead of one. POSIX.1\(hy2008 requires that this be changed for +consistency with the other text input commands of +.IR vi . +.P +Historically, it is an error to enter the +.BR r +command if there are less than +.IR count +characters at or after the cursor in the line. While a reasonable and +unambiguous extension would be to permit the +.BR r +command on empty lines, it would require that too large a +.IR count +be adjusted to match the number of characters at or after the cursor +for consistency, which is sufficiently different from historical +practice to be avoided. POSIX.1\(hy2008 requires conformance to historical +practice. +.SS "Replace Characters" +.P +Historically, if there were +.BR autoindent +characters in the line on which the +.BR R +command was run, and +.BR autoindent +was set, the first +<newline> +would be properly indented and no characters would be replaced by the +<newline>. +Each additional +<newline> +would replace +.IR n +characters, where +.IR n +was the number of characters that were needed to indent the rest of the +line to the proper indentation level. This behavior is a bug and is not +permitted by POSIX.1\(hy2008. +.SS "Undo" +.P +Historical practice for cursor positioning after undoing commands was +mixed. In most cases, when undoing commands that affected a single +line, the cursor was moved to the start of added or changed text, or +immediately after deleted text. However, if the user had moved from the +line being changed, the column was either set to the first non-\c +<blank>, +returned to the origin of the command, or remained unchanged. When +undoing commands that affected multiple lines or entire lines, the +cursor was moved to the first character in the first line restored. As +an example of how inconsistent this was, a search, followed by an +.BR o +text input command, followed by an +.BR undo +would return the cursor to the location where the +.BR o +command was entered, but a +.BR cw +command followed by an +.BR o +command followed by an +.BR undo +would return the cursor to the first non-\c +<blank> +of the line. POSIX.1\(hy2008 requires the most useful of these behaviors, and +discards the least useful, in the interest of consistency and +simplicity of specification. +.SS "Yank" +.P +Historically, the +.BR yank +command did not move to the end of the motion if the motion was in the +forward direction. It moved to the end of the motion if the motion was +in the backward direction, except for the +.BR _ +command, or for the +.BR G +and +.BR \(aq +commands when the end of the motion was on the current line. This was +further complicated by the fact that for a number of motion commands, +the +.BR yank +command moved the cursor but did not update the screen; for example, a +subsequent command would move the cursor from the end of the motion, +even though the cursor on the screen had not reflected the cursor +movement for the +.BR yank +command. POSIX.1\(hy2008 requires that all +.BR yank +commands associated with backward motions move the cursor to the end of +the motion for consistency, and specifically, to make +.BR \(aq +commands as motions consistent with search patterns as motions. +.SS "Yank Current Line" +.P +Some historical implementations of the +.BR Y +command did not behave as described by POSIX.1\(hy2008 when the +.BR '_' +key was remapped because they were implemented by pushing the +.BR '_' +key onto the input queue and reprocessing it. POSIX.1\(hy2008 does not permit +this behavior. +.SS "Redraw Window" +.P +Historically, the +.BR z +command always redrew the screen. This is permitted but not required by +POSIX.1\(hy2008, because of the frequent use of the +.BR z +command in macros such as +.BR "map n nz." +for screen positioning, instead of its use to change the screen size. +The standard developers believed that expanding or scrolling the screen +offered a better interface for users. The ability to redraw the screen +is preserved if the optional new window size is specified, and in the +<control>\(hyL +and +<control>\(hyR +commands. +.P +The semantics of +.BR z^ +are confusing at best. Historical practice is that the screen before +the screen that ended with the specified line is displayed. POSIX.1\(hy2008 +requires conformance to historical practice. +.P +Historically, the +.BR z +command would not display a partial line at the top or bottom of the +screen. If the partial line would normally have been displayed at the +bottom of the screen, the command worked, but the partial line was +replaced with +.BR '@' +characters. If the partial line would normally have been displayed at +the top of the screen, the command would fail. For consistency and +simplicity of specification, POSIX.1\(hy2008 does not permit this behavior. +.P +Historically, the +.BR z +command with a line specification of 1 ignored the command. For +consistency and simplicity of specification, POSIX.1\(hy2008 does not permit this +behavior. +.P +Historically, the +.BR z +command did not set the cursor column to the first non-\c +<blank> +for the character if the first screen was to be displayed, and was +already displayed. For consistency and simplicity of specification, +POSIX.1\(hy2008 does not permit this behavior. +.SS "Input Mode Commands in vi" +.P +Historical implementations of +.IR vi +did not permit the user to erase more than a single line of input, +or to use normal erase characters such as +.IR "line erase" , +.IR worderase , +and +.IR erase +to erase +.BR autoindent +characters. As there exist implementations of +.IR vi +that do not have these limitations, both behaviors are permitted, but +only historical practice is required. In the case of these extensions, +.IR vi +is required to pause at the +.BR autoindent +and previous line boundaries. +.P +Historical implementations of +.IR vi +updated only the portion of the screen where the current cursor +character was displayed. For example, consider the +.IR vi +input keystrokes: +.sp +.RS 4 +.nf + +iabcd<escape>0C<tab> +.fi +.P +.RE +.P +Historically, the +<tab> +would overwrite the characters +.BR \(dqabcd\(dq +when it was displayed. Other implementations replace only the +.BR 'a' +character with the +<tab>, +and then push the rest of the characters ahead of the cursor. Both +implementations have problems. The historical implementation is +probably visually nicer for the above example; however, for the +keystrokes: +.sp +.RS 4 +.nf + +iabcd<ESC>0R<tab><ESC> +.fi +.P +.RE +.P +the historical implementation results in the string +.BR \(dqbcd\(dq +disappearing and then magically reappearing when the +<ESC> +character is entered. POSIX.1\(hy2008 requires the former behavior when +overwriting erase-columns\(emthat is, overwriting characters that are no +longer logically part of the edit buffer\(emand the latter behavior +otherwise. +.P +Historical implementations of +.IR vi +discarded the +<control>\(hyD +and +<control>\(hyT +characters when they were entered at places where their command +functionality was not appropriate. POSIX.1\(hy2008 requires that the +<control>\(hyT +functionality always be available, and that +<control>\(hyD +be treated as any other key when not operating on +.BR autoindent +characters. +.SS "NUL" +.P +Some historical implementations of +.IR vi +limited the number of characters entered using the NUL input character +to 256 bytes. POSIX.1\(hy2008 permits this limitation; however, implementations +are encouraged to remove this limit. +.SS "<control>\(hyD" +.P +See also Rationale for the input mode command +<newline>. +The hidden assumptions in the +<control>\(hyD +command (and in the +.IR vi +.BR autoindent +specification in general) is that +<space> +characters take up a single column on the screen and that +<tab> +characters are comprised of an integral number of +<space> +characters. +.SS "<newline>" +.P +Implementations are permitted to rewrite +.BR autoindent +characters in the line when +<newline>, +<carriage-return>, +<control>\(hyD, +and +<control>\(hyT +are entered, or when the +.BR shift +commands are used, because historical implementations have both done so +and found it necessary to do so. For example, a +<control>\(hyD +when the cursor is preceded by a single +<tab>, +with +.BR tabstop +set to 8, and +.BR shiftwidth +set to 3, will result in the +<tab> +being replaced by several +<space> +characters. +.SS "<control>\(hyT" +.P +See also the Rationale for the input mode command +<newline>. +Historically, +<control>\(hyT +only worked if no non-\c +<blank> +characters had yet been input in the current input line. In addition, +the characters inserted by +<control>\(hyT +were treated as +.BR autoindent +characters, and could not be erased using normal user erase characters. +Because implementations exist that do not have these limitations, and +as moving to a column boundary is generally useful, POSIX.1\(hy2008 requires that +both limitations be removed. +.SS "<control>\(hyV" +.P +Historically, +.IR vi +used +.BR ^V , +regardless of the value of the literal-next character of the terminal. +POSIX.1\(hy2008 requires conformance to historical practice. +.P +The uses described for +<control>\(hyV +can also be accomplished with +<control>\(hyQ, +which is useful on terminals that use +<control>\(hyV +for the down-arrow function. However, most historical implementations +use +<control>\(hyQ +for the +.IR termios +START character, so the editor will generally not receive the +<control>\(hyQ +unless +.BR "stty ixon" +mode is set to off. (In addition, some historical implementations of +.IR vi +explicitly set +.BR ixon +mode to on, so it was difficult for the user to set it to off.) Any of +the command characters described in POSIX.1\(hy2008 can be made ineffective by +their selection as +.IR termios +control characters, using the +.IR stty +utility or other methods described in the System Interfaces volume of POSIX.1\(hy2017. +.SS "<ESC>" +.P +Historically, SIGINT alerted the terminal when used to end input +mode. This behavior is permitted, but not required, by POSIX.1\(hy2008. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIed\fR\^", +.IR "\fIex\fR\^", +.IR "\fIstty\fR\^" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "Section 12.2" ", " "Utility Syntax Guidelines" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +In the event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |