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vi.1p (155097B)

    

  1. '\" et
  2. .TH VI "1P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
  3. .\"
  4. .SH PROLOG
  5. This manual page is part of the POSIX Programmer's Manual.
  6. The Linux implementation of this interface may differ (consult
  7. the corresponding Linux manual page for details of Linux behavior),
  8. or the interface may not be implemented on Linux.
  9. .\"
  10. .SH NAME
  11. vi
  12. \(em screen-oriented (visual) display editor
  13. .SH SYNOPSIS
  14. .LP
  15. .nf
  16. vi \fB[\fR-rR\fB] [\fR-c \fIcommand\fB] [\fR-t \fItagstring\fB] [\fR-w \fIsize\fB] [\fIfile\fR...\fB]\fR
  17. .fi
  18. .SH DESCRIPTION
  19. This utility shall be provided on systems that both support the User
  20. Portability Utilities option and define the POSIX2_CHAR_TERM symbol.
  21. On other systems it is optional.
  22. .P
  23. The
  24. .IR vi
  25. (visual) utility is a screen-oriented text editor. Only the open and
  26. visual modes of the editor are described in POSIX.1\(hy2008; see the line editor
  27. .IR ex
  28. for additional editing capabilities used in
  29. .IR vi .
  30. The user can switch back and forth between
  31. .IR vi
  32. and
  33. .IR ex
  34. and execute
  35. .IR ex
  36. commands from within
  37. .IR vi .
  38. .P
  39. This reference page uses the term
  40. .IR "edit buffer"
  41. to describe the current working text. No specific implementation is
  42. implied by this term. All editing changes are performed on the edit
  43. buffer, and no changes to it shall affect any file until an editor
  44. command writes the file.
  45. .P
  46. When using
  47. .IR vi ,
  48. the terminal screen acts as a window into the editing buffer. Changes
  49. made to the editing buffer shall be reflected in the screen display;
  50. the position of the cursor on the screen shall indicate the position
  51. within the editing buffer.
  52. .P
  53. Certain terminals do not have all the capabilities necessary to support
  54. the complete
  55. .IR vi
  56. definition. When these commands cannot be supported on such terminals,
  57. this condition shall not produce an error message such as ``not an
  58. editor command'' or report a syntax error. The implementation may
  59. either accept the commands and produce results on the screen that are
  60. the result of an unsuccessful attempt to meet the requirements of this volume of POSIX.1\(hy2017
  61. or report an error describing the terminal-related deficiency.
  62. .SH OPTIONS
  63. The
  64. .IR vi
  65. utility shall conform to the Base Definitions volume of POSIX.1\(hy2017,
  66. .IR "Section 12.2" ", " "Utility Syntax Guidelines",
  67. except that
  68. .BR '\(pl' 
  69. may be recognized as an option delimiter as well as
  70. .BR '\-' .
  71. .P
  72. The following options shall be supported:
  73. .IP "\fB\-c\ \fIcommand\fR" 10
  74. See the
  75. .IR ex
  76. command description of the
  77. .BR \-c
  78. option.
  79. .IP "\fB\-r\fP" 10
  80. See the
  81. .IR ex
  82. command description of the
  83. .BR \-r
  84. option.
  85. .IP "\fB\-R\fP" 10
  86. See the
  87. .IR ex
  88. command description of the
  89. .BR \-R
  90. option.
  91. .IP "\fB\-t\ \fItagstring\fR" 10
  92. See the
  93. .IR ex
  94. command description of the
  95. .BR \-t
  96. option.
  97. .IP "\fB\-w\ \fIsize\fR" 10
  98. See the
  99. .IR ex
  100. command description of the
  101. .BR \-w
  102. option.
  103. .SH OPERANDS
  104. See the OPERANDS section of the
  105. .IR ex
  106. command for a description of the operands supported by the
  107. .IR vi
  108. command.
  109. .SH STDIN
  110. If standard input is not a terminal device, the results are undefined.
  111. The standard input consists of a series of commands and input text, as
  112. described in the EXTENDED DESCRIPTION section.
  113. .P
  114. If a read from the standard input returns an error, or if the editor
  115. detects an end-of-file condition from the standard input, it shall be
  116. equivalent to a SIGHUP asynchronous event.
  117. .SH "INPUT FILES"
  118. See the INPUT FILES section of the
  119. .IR ex
  120. command for a description of the input files supported by the
  121. .IR vi
  122. command.
  123. .SH "ENVIRONMENT VARIABLES"
  124. See the ENVIRONMENT VARIABLES section of the
  125. .IR ex
  126. command for the environment variables that affect the execution of the
  127. .IR vi
  128. command.
  129. .SH "ASYNCHRONOUS EVENTS"
  130. See the ASYNCHRONOUS EVENTS section of the
  131. .IR ex
  132. for the asynchronous events that affect the execution of the
  133. .IR vi
  134. command.
  135. .SH STDOUT
  136. If standard output is not a terminal device, undefined results occur.
  137. .P
  138. Standard output may be used for writing prompts to the user, for
  139. informational messages, and for writing lines from the file.
  140. .SH STDERR
  141. If standard output is not a terminal device, undefined results occur.
  142. .P
  143. The standard error shall be used only for diagnostic messages.
  144. .SH "OUTPUT FILES"
  145. See the OUTPUT FILES section of the
  146. .IR ex
  147. command for a description of the output files supported by the
  148. .IR vi
  149. command.
  150. .SH "EXTENDED DESCRIPTION"
  151. If the terminal does not have the capabilities necessary to support an
  152. unspecified portion of the
  153. .IR vi
  154. definition, implementations shall start initially in
  155. .IR ex
  156. mode or open mode. Otherwise, after initialization,
  157. .IR vi
  158. shall be in command mode; text input mode can be entered by one of
  159. several commands used to insert or change text. In text input mode,
  160. <ESC>
  161. can be used to return to command mode; other uses of
  162. <ESC>
  163. are described later in this section; see
  164. .IR "Terminate Command or Input Mode".
  165. .SS "Initialization in ex and vi"
  166. .P
  167. See
  168. .IR "Initialization in ex and vi"
  169. for a description of
  170. .IR ex
  171. and
  172. .IR vi
  173. initialization for the
  174. .IR vi
  175. utility.
  176. .SS "Command Descriptions in vi"
  177. .P
  178. The following symbols are used in this reference page to represent
  179. arguments to commands.
  180. .IP "\fIbuffer\fR" 8
  181. See the description of
  182. .IR buffer
  183. in the EXTENDED DESCRIPTION section of the
  184. .IR ex
  185. utility; see
  186. .IR "Command Descriptions in ex".
  187. .RS 8 
  188. .P
  189. In open and visual mode, when a command synopsis shows both [\c
  190. .IR buffer ]
  191. and [\c
  192. .IR count ]
  193. preceding the command name, they can be specified in either order.
  194. .RE
  195. .IP "\fIcount\fR" 8
  196. A positive integer used as an optional argument to most commands,
  197. either to give a repeat count or as a size. This argument is optional
  198. and shall default to 1 unless otherwise specified.
  199. .RS 8 
  200. .P
  201. The Synopsis lines for the
  202. .IR vi
  203. commands
  204. <control>\(hyG,
  205. <control>\(hyL,
  206. <control>\(hyR,
  207. <control>\(hy],
  208. .BR % ,
  209. .BR & ,
  210. .BR ^ ,
  211. .BR D ,
  212. .BR m ,
  213. .BR M ,
  214. .BR Q ,
  215. .BR u ,
  216. .BR U ,
  217. and
  218. .BR ZZ
  219. do not have
  220. .IR count
  221. as an optional argument. Regardless, it shall not be an error to
  222. specify a
  223. .IR count
  224. to these commands, and any specified
  225. .IR count
  226. shall be ignored.
  227. .RE
  228. .IP "\fImotion\fR" 8
  229. An optional trailing argument used by the
  230. .BR ! ,
  231. .BR < ,
  232. .BR > ,
  233. .BR c ,
  234. .BR d ,
  235. and
  236. .BR y
  237. commands, which is used to indicate the region of text that shall be
  238. affected by the command. The motion can be either one of the command
  239. characters repeated or one of several other
  240. .IR vi
  241. commands (listed in the following table). Each of the applicable
  242. commands specifies the region of text matched by repeating the command;
  243. each command that can be used as a motion command specifies the region
  244. of text it affects.
  245. .RS 8 
  246. .P
  247. Commands that take
  248. .IR motion
  249. arguments operate on either lines or characters, depending on the
  250. circumstances. When operating on lines, all lines that fall partially
  251. or wholly within the text region specified for the command shall be
  252. affected. When operating on characters, only the exact characters in
  253. the specified text region shall be affected. Each motion command
  254. specifies this individually.
  255. .P
  256. When commands that may be motion commands are not used as motion
  257. commands, they shall set the current position to the current line and
  258. column as specified.
  259. .P
  260. The following commands shall be valid cursor motion commands:
  261. .sp
  262. .RS 4
  263. .nf
  265. <apostrophe>       (    -    j    H
  266. <carriage-return>  )    $    k    L
  267. <comma>            [[   %    l    M
  268. <control>-H        ]]   _    n    N
  269. <control>-N        {    ;    t    T
  270. <control>-P        }    ?    w    W
  271. <grave-accent>     \(ha    b    B
  272. <newline>          +    e    E
  273. <space>            |    f    F
  274. <zero>             /    h    G
  275. .fi
  276. .P
  277. .RE
  278. .P
  279. Any
  280. .IR count
  281. that is specified to a command that has an associated motion command
  282. shall be applied to the motion command. If a
  283. .IR count
  284. is applied to both the command and its associated motion command, the
  285. effect shall be multiplicative.
  286. .RE
  287. .P
  288. The following symbols are used in this section to specify locations
  289. in the edit buffer:
  290. .IP "\fIcurrent\ character\fP" 8
  291. .br
  292. The character that is currently indicated by the cursor.
  293. .IP "\fIend\ of\ a\ line\fP" 8
  294. .br
  295. The point located between the last non-\c
  296. <newline>
  297. (if any) and the terminating
  298. <newline>
  299. of a line. For an empty line, this location coincides with the
  300. beginning of the line.
  301. .IP "\fIend\ of\ the\ edit\ buffer\fP" 8
  302. .br
  303. The location corresponding to the end of the last line in the edit
  304. buffer.
  305. .P
  306. The following symbols are used in this section to specify command
  307. actions:
  308. .IP "\fIbigword\fP" 8
  309. In the POSIX locale,
  310. .IR vi
  311. shall recognize four kinds of
  312. .IR bigwords :
  313. .RS 8 
  314. .IP " 1." 4
  315. A maximal sequence of non-\c
  316. <blank>
  317. characters preceded and followed by
  318. <blank>
  319. characters or the beginning or end of a line or the edit buffer
  320. .IP " 2." 4
  321. One or more sequential blank lines
  322. .IP " 3." 4
  323. The first character in the edit buffer
  324. .IP " 4." 4
  325. The last non-\c
  326. <newline>
  327. in the edit buffer
  328. .RE
  329. .IP "\fIword\fP" 8
  330. In the POSIX locale,
  331. .IR vi
  332. shall recognize five kinds of words:
  333. .RS 8 
  334. .IP " 1." 4
  335. A maximal sequence of letters, digits, and underscores, delimited at
  336. both ends by:
  337. .RS 4 
  338. .IP -- 4
  339. Characters other than letters, digits, or underscores
  340. .IP -- 4
  341. The beginning or end of a line
  342. .IP -- 4
  343. The beginning or end of the edit buffer
  344. .RE
  345. .IP " 2." 4
  346. A maximal sequence of characters other than letters, digits, underscores, or
  347. <blank>
  348. characters, delimited at both ends by:
  349. .RS 4 
  350. .IP -- 4
  351. A letter, digit, underscore
  352. .IP -- 4
  353. <blank>
  354. characters
  355. .IP -- 4
  356. The beginning or end of a line
  357. .IP -- 4
  358. The beginning or end of the edit buffer
  359. .RE
  360. .IP " 3." 4
  361. One or more sequential blank lines
  362. .IP " 4." 4
  363. The first character in the edit buffer
  364. .IP " 5." 4
  365. The last non-\c
  366. <newline>
  367. in the edit buffer
  368. .RE
  369. .IP "\fIsection\ boundary\fR" 8
  370. .br
  371. A
  372. .IR "section boundary"
  373. is one of the following:
  374. .RS 8 
  375. .IP " 1." 4
  376. A line whose first character is a
  377. <form-feed>
  378. .IP " 2." 4
  379. A line whose first character is an open curly brace (\c
  380. .BR '{' )
  381. .IP " 3." 4
  382. A line whose first character is a
  383. <period>
  384. and whose second and third characters match a two-character pair in the
  385. .BR sections
  386. edit option (see
  387. .IR ex )
  388. .IP " 4." 4
  389. A line whose first character is a
  390. <period>
  391. and whose only other character matches the first character of a
  392. two-character pair in the
  393. .BR sections
  394. edit option, where the second character of the two-character pair is a
  395. <space>
  396. .IP " 5." 4
  397. The first line of the edit buffer
  398. .IP " 6." 4
  399. The last line of the edit buffer if the last line of the edit buffer is
  400. empty or if it is a
  401. .BR ]]
  402. or
  403. .BR }
  404. command; otherwise, the last non-\c
  405. <newline>
  406. of the last line of the edit buffer
  407. .RE
  408. .IP "\fIparagraph\ boundary\fR" 8
  409. .br
  410. A
  411. .IR "paragraph boundary"
  412. is one of the following:
  413. .RS 8 
  414. .IP " 1." 4
  415. A section boundary
  416. .IP " 2." 4
  417. A line whose first character is a
  418. <period>
  419. and whose second and third characters match a two-character pair in the
  420. .BR paragraphs
  421. edit option (see
  422. .IR ex )
  423. .IP " 3." 4
  424. A line whose first character is a
  425. <period>
  426. and whose only other character matches the first character of a
  427. two-character pair in the
  428. .IR paragraphs
  429. edit option, where the second character of the two-character pair is a
  430. <space>
  431. .IP " 4." 4
  432. One or more sequential blank lines
  433. .RE
  434. .IP "\fIremembered\ search\ direction\fR" 8
  435. .br
  436. See the description of \fIremembered search direction\fP in
  437. .IR ex .
  438. .IP "\fIsentence\ boundary\fR" 8
  439. .br
  440. A
  441. .IR "sentence boundary"
  442. is one of the following:
  443. .RS 8 
  444. .IP " 1." 4
  445. A paragraph boundary
  446. .IP " 2." 4
  447. The first non-\c
  448. <blank>
  449. that occurs after a paragraph boundary
  450. .IP " 3." 4
  451. The first non-\c
  452. <blank>
  453. that occurs after a
  454. <period>
  455. (\c
  456. .BR '.' ),
  457. <exclamation-mark>
  458. (\c
  459. .BR '!' ),
  460. or
  461. <question-mark>
  462. (\c
  463. .BR '?' ),
  464. followed by two
  465. <space>
  466. characters or the end of a line; any number of closing parenthesis (\c
  467. .BR ')' ),
  468. closing brackets (\c
  469. .BR ']' ),
  470. double-quote (\c
  471. .BR '\&"' ),
  472. or single-quote (\c
  473. <apostrophe>)
  474. characters can appear between the punctuation mark and the two
  475. <space>
  476. characters or end-of-line
  477. .RE
  478. .P
  479. In the remainder of the description of the
  480. .IR vi
  481. utility, the term ``buffer line'' refers to a line in the edit buffer
  482. and the term ``display line'' refers to the line or lines on the
  483. display screen used to display one buffer line. The term ``current
  484. line'' refers to a specific ``buffer line''.
  485. .P
  486. If there are display lines on the screen for which there are no
  487. corresponding buffer lines because they correspond to lines that would
  488. be after the end of the file, they shall be displayed as a single
  489. <tilde>
  490. (\c
  491. .BR '\(ti' )
  492. character, plus the terminating
  493. <newline>.
  494. .P
  495. The last line of the screen shall be used to report errors or display
  496. informational messages. It shall also be used to display the input for
  497. ``line-oriented commands'' (\c
  498. .BR / ,
  499. .BR ? ,
  500. .BR : ,
  501. and
  502. .BR ! ).
  503. When a line-oriented command is executed, the editor shall enter text
  504. input mode on the last line on the screen, using the respective command
  505. characters as prompt characters. (In the case of the
  506. .BR !
  507. command, the associated motion shall be entered by the user before the
  508. editor enters text input mode.) The line entered by the user shall be
  509. terminated by a
  510. <newline>,
  511. a non-\c
  512. <control>\(hyV-escaped
  513. <carriage-return>,
  514. or unescaped
  515. <ESC>.
  516. It is unspecified if more characters than require a display width minus
  517. one column number of screen columns can be entered.
  518. .P
  519. If any command is executed that overwrites a portion of the screen
  520. other than the last line of the screen (for example, the
  521. .IR ex
  522. .BR suspend
  523. or
  524. .BR !
  525. commands), other than the
  526. .IR ex
  527. .BR shell
  528. command, the user shall be prompted for a character before the screen
  529. is refreshed and the edit session continued.
  530. .P
  531. <tab>
  532. characters shall take up the number of columns on the screen set by the
  533. .BR tabstop
  534. edit option (see
  535. .IR ex ),
  536. unless there are less than that number of columns before the display
  537. margin that will cause the displayed line to be folded; in this case,
  538. they shall only take up the number of columns up to that boundary.
  539. .P
  540. The cursor shall be placed on the current line and relative to the
  541. current column as specified by each command described in the following
  542. sections.
  543. .P
  544. In open mode, if the current line is not already displayed, then it
  545. shall be displayed.
  546. .P
  547. In visual mode, if the current line is not displayed, then the lines
  548. that are displayed shall be expanded, scrolled, or redrawn to cause an
  549. unspecified portion of the current line to be displayed. If the screen
  550. is redrawn, no more than the number of display lines specified by the
  551. value of the
  552. .BR window
  553. edit option shall be displayed (unless the current line cannot be
  554. completely displayed in the number of display lines specified by the
  555. .BR window
  556. edit option) and the current line shall be positioned as close to the
  557. center of the displayed lines as possible (within the constraints
  558. imposed by the distance of the line from the beginning or end of the
  559. edit buffer). If the current line is before the first line in the
  560. display and the screen is scrolled, an unspecified portion of the
  561. current line shall be placed on the first line of the display. If the
  562. current line is after the last line in the display and the screen is
  563. scrolled, an unspecified portion of the current line shall be placed on
  564. the last line of the display.
  565. .P
  566. In visual mode, if a line from the edit buffer (other than the current
  567. line) does not entirely fit into the lines at the bottom of the display
  568. that are available for its presentation, the editor may choose not to
  569. display any portion of the line. The lines of the display that do not
  570. contain text from the edit buffer for this reason shall each consist of
  571. a single
  572. .BR '@' 
  573. character.
  574. .P
  575. In visual mode, the editor may choose for unspecified reasons to not
  576. update lines in the display to correspond to the underlying edit buffer
  577. text. The lines of the display that do not correctly correspond to text
  578. from the edit buffer for this reason shall consist of a single
  579. .BR '@' 
  580. character (plus the terminating
  581. <newline>),
  582. and the
  583. <control>\(hyR
  584. command shall cause the editor to update the screen to correctly
  585. represent the edit buffer.
  586. .P
  587. Open and visual mode commands that set the current column set it to a
  588. column position in the display, and not a character position in the
  589. line. In this case, however, the column position in the display shall
  590. be calculated for an infinite width display; for example, the column
  591. related to a character that is part of a line that has been folded onto
  592. additional screen lines will be offset from the display line column
  593. where the buffer line begins, not from the beginning of a particular
  594. display line.
  595. .P
  596. The display cursor column in the display is based on the value of the
  597. current column, as follows, with each rule applied in turn:
  598. .IP " 1." 4
  599. If the current column is after the last display line column used by the
  600. displayed line, the display cursor column shall be set to the last
  601. display line column occupied by the last non-\c
  602. <newline>
  603. in the current line; otherwise, the display cursor column shall be set
  604. to the current column.
  605. .IP " 2." 4
  606. If the character of which some portion is displayed in the display line
  607. column specified by the display cursor column requires more than a
  608. single display line column:
  609. .RS 4 
  610. .IP " a." 4
  611. If in text input mode, the display cursor column shall be adjusted to
  612. the first display line column in which any portion of that character is
  613. displayed.
  614. .IP " b." 4
  615. Otherwise, the display cursor column shall be adjusted to the last
  616. display line column in which any portion of that character is
  617. displayed.
  618. .RE
  619. .P
  620. The current column shall not be changed by these adjustments to the
  621. display cursor column.
  622. .P
  623. If an error occurs during the parsing or execution of a
  624. .IR vi
  625. command:
  626. .IP " *" 4
  627. The terminal shall be alerted. Execution of the
  628. .IR vi
  629. command shall stop, and the cursor (for example, the current line and
  630. column) shall not be further modified.
  631. .IP " *" 4
  632. Unless otherwise specified by the following command sections, it is
  633. unspecified whether an informational message shall be displayed.
  634. .IP " *" 4
  635. Any partially entered
  636. .IR vi
  637. command shall be discarded.
  638. .IP " *" 4
  639. If the
  640. .IR vi
  641. command resulted from a
  642. .BR map
  643. expansion, all characters from that
  644. .BR map
  645. expansion shall be discarded, except as otherwise specified by the
  646. .BR map
  647. command (see
  648. .IR ex ).
  649. .IP " *" 4
  650. If the
  651. .IR vi
  652. command resulted from the execution of a buffer, no further commands
  653. caused by the execution of the buffer shall be executed.
  654. .SS "Page Backwards"
  655. .IP "\fISynopsis\fR:" 10
  656. .sp -1v
  657. .RS 10 
  658. .sp
  659. .RS 4
  660. .nf
  662. \fB[\fIcount\fB]\fR <control>-B
  663. .fi
  664. .P
  665. .RE
  666. .RE
  667. .P
  668. If in open mode, the
  669. <control>\(hyB
  670. command shall behave identically to the
  671. .BR z
  672. command. Otherwise, if the current line is the first line of the edit
  673. buffer, it shall be an error.
  674. .P
  675. If the
  676. .BR window
  677. edit option is less than 3, display a screen where the last line of the
  678. display shall be some portion of:
  679. .sp
  680. .RS 4
  681. .nf
  683. (\fIcurrent first line\fR) -1
  684. .fi
  685. .P
  686. .RE
  687. .P
  688. otherwise, display a screen where the first line of the display shall
  689. be some portion of:
  690. .sp
  691. .RS 4
  692. .nf
  694. (\fIcurrent first line\fR) - \fIcount\fR x ((window edit option) -2)
  695. .fi
  696. .P
  697. .RE
  698. .P
  699. If this calculation would result in a line that is before the first
  700. line of the edit buffer, the first line of the display shall display
  701. some portion of the first line of the edit buffer.
  702. .P
  703. .IR "Current line" :
  704. If no lines from the previous display remain on the screen, set to the
  705. last line of the display; otherwise, set to (\c
  706. .IR line
  707. \- the number of new lines displayed on this screen).
  708. .P
  709. .IR "Current column" :
  710. Set to non-\c
  711. <blank>.
  712. .SS "Scroll Forward"
  713. .IP "\fISynopsis\fR:" 10
  714. .sp -1v
  715. .RS 10 
  716. .sp
  717. .RS 4
  718. .nf
  720. \fB[\fIcount\fB]\fR <control>-D
  721. .fi
  722. .P
  723. .RE
  724. .RE
  725. .P
  726. If the current line is the last line of the edit buffer, it shall be an
  727. error.
  728. .P
  729. If no
  730. .IR count
  731. is specified,
  732. .IR count
  733. shall default to the
  734. .IR count
  735. associated with the previous
  736. <control>\(hyD
  737. or
  738. <control>\(hyU
  739. command. If there was no previous
  740. <control>\(hyD
  741. or
  742. <control>\(hyU
  743. command,
  744. .IR count
  745. shall default to the value of the
  746. .BR scroll
  747. edit option.
  748. .P
  749. If in open mode, write lines starting with the line after the current
  750. line, until
  751. .IR count
  752. lines or the last line of the file have been written.
  753. .P
  754. .IR "Current line" :
  755. If the current line +
  756. .IR count
  757. is past the last line of the edit buffer, set to the last line of the
  758. edit buffer; otherwise, set to the current line +
  759. .IR count .
  760. .P
  761. .IR "Current column" :
  762. Set to non-\c
  763. <blank>.
  764. .SS "Scroll Forward by Line"
  765. .IP "\fISynopsis\fR:" 10
  766. .sp -1v
  767. .RS 10 
  768. .sp
  769. .RS 4
  770. .nf
  772. \fB[\fIcount\fB]\fR <control>-E
  773. .fi
  774. .P
  775. .RE
  776. .RE
  777. .P
  778. Display the line count lines after the last line currently displayed.
  779. .P
  780. If the last line of the edit buffer is displayed, it shall be an error.
  781. If there is no line
  782. .IR count
  783. lines after the last line currently displayed, the last line of the
  784. display shall display some portion of the last line of the edit
  785. buffer.
  786. .P
  787. .IR "Current line" :
  788. Unchanged if the previous current character is displayed; otherwise,
  789. set to the first line displayed.
  790. .P
  791. .IR "Current column" :
  792. Unchanged.
  793. .SS "Page Forward"
  794. .IP "\fISynopsis\fR:" 10
  795. .sp -1v
  796. .RS 10 
  797. .sp
  798. .RS 4
  799. .nf
  801. \fB[\fIcount\fB]\fR <control>-F
  802. .fi
  803. .P
  804. .RE
  805. .RE
  806. .P
  807. If in open mode, the
  808. <control>\(hyF
  809. command shall behave identically to the
  810. .BR z
  811. command. Otherwise, if the current line is the last line of the edit
  812. buffer, it shall be an error.
  813. .P
  814. If the
  815. .BR window
  816. edit option is less than 3, display a screen where the first line of
  817. the display shall be some portion of:
  818. .sp
  819. .RS 4
  820. .nf
  822. (\fIcurrent last line\fR) +1
  823. .fi
  824. .P
  825. .RE
  826. .P
  827. otherwise, display a screen where the first line of the display shall
  828. be some portion of:
  829. .sp
  830. .RS 4
  831. .nf
  833. (\fIcurrent first line\fR) + \fIcount\fR x ((window edit option) -2)
  834. .fi
  835. .P
  836. .RE
  837. .P
  838. If this calculation would result in a line that is after the last line
  839. of the edit buffer, the last line of the display shall display some
  840. portion of the last line of the edit buffer.
  841. .P
  842. .IR "Current line" :
  843. If no lines from the previous display remain on the screen, set to the
  844. first line of the display; otherwise, set to (\c
  845. .IR line
  846. + the number of new lines displayed on this screen).
  847. .P
  848. .IR "Current column" :
  849. Set to non-\c
  850. <blank>.
  851. .SS "Display Information"
  852. .IP "\fISynopsis\fR:" 10
  853. .sp -1v
  854. .RS 10 
  855. .sp
  856. .RS 4
  857. .nf
  859. <control>-G
  860. .fi
  861. .P
  862. .RE
  863. .RE
  864. .P
  865. This command shall be equivalent to the
  866. .IR ex
  867. .BR file
  868. command.
  869. .SS "Move Cursor Backwards"
  870. .IP "\fISynopsis\fR:" 10
  871. .sp -1v
  872. .RS 10 
  873. .sp
  874. .RS 4
  875. .nf
  877. \fB[\fIcount\fB]\fR <control>-H
  878. .br
  879. \fB[\fIcount\fB]\fR h
  880. .br
  881. the current \fIerase\fP character (see stty)
  882. .fi
  883. .P
  884. .RE
  885. .RE
  886. .P
  887. If there are no characters before the current character on the current
  888. line, it shall be an error. If there are less than
  889. .IR count
  890. previous characters on the current line,
  891. .IR count
  892. shall be adjusted to the number of previous characters on the line.
  893. .P
  894. If used as a motion command:
  895. .IP " 1." 4
  896. The text region shall be from the character before the starting cursor
  897. up to and including the
  898. .IR count th
  899. character before the starting cursor.
  900. .IP " 2." 4
  901. Any text copied to a buffer shall be in character mode.
  902. .P
  903. If not used as a motion command:
  904. .P
  905. .IR "Current line" :
  906. Unchanged.
  907. .P
  908. .IR "Current column" :
  909. Set to (\c
  910. .IR column
  911. \- the number of columns occupied by
  912. .IR count
  913. characters ending with the previous current column).
  914. .SS "Move Down"
  915. .IP "\fISynopsis\fR:" 10
  916. .sp -1v
  917. .RS 10 
  918. .sp
  919. .RS 4
  920. .nf
  922. \fB[\fIcount\fB]\fR <newline>
  923. .br
  924. \fB[\fIcount\fB]\fR <control>-J
  925. .br
  926. \fB[\fIcount\fB]\fR <control>-M
  927. .br
  928. \fB[\fIcount\fB]\fR <control>-N
  929. .br
  930. \fB[\fIcount\fB]\fR j
  931. .br
  932. \fB[\fIcount\fB]\fR <carriage-return>
  933. .br
  934. \fB[\fIcount\fB]\fR +
  935. .fi
  936. .P
  937. .RE
  938. .RE
  939. .P
  940. If there are less than
  941. .IR count
  942. lines after the current line in the edit buffer, it shall be an error.
  943. .P
  944. If used as a motion command:
  945. .IP " 1." 4
  946. The text region shall include the starting line and the next
  947. .IR count
  948. \- 1 lines.
  949. .IP " 2." 4
  950. Any text copied to a buffer shall be in line mode.
  951. .P
  952. If not used as a motion command:
  953. .P
  954. .IR "Current line" :
  955. Set to
  956. .IR "current line" +
  957. .IR count .
  958. .P
  959. .IR "Current column" :
  960. Set to non-\c
  961. <blank>
  962. for the
  963. <carriage-return>,
  964. <control>\(hyM,
  965. and
  966. .BR +
  967. commands; otherwise, unchanged.
  968. .SS "Clear and Redisplay"
  969. .IP "\fISynopsis\fR:" 10
  970. .sp -1v
  971. .RS 10 
  972. .sp
  973. .RS 4
  974. .nf
  976. <control>-L
  977. .fi
  978. .P
  979. .RE
  980. .RE
  981. .P
  982. If in open mode, clear the screen and redisplay the current line.
  983. Otherwise, clear and redisplay the screen.
  984. .P
  985. .IR "Current line" :
  986. Unchanged.
  987. .P
  988. .IR "Current column" :
  989. Unchanged.
  990. .SS "Move Up"
  991. .IP "\fISynopsis\fR:" 10
  992. .sp -1v
  993. .RS 10 
  994. .sp
  995. .RS 4
  996. .nf
  998. \fB[\fIcount\fB]\fR <control>-P
  999. .br
  1000. \fB[\fIcount\fB]\fR k
  1001. .br
  1002. \fB[\fIcount\fB]\fR -
  1003. .fi
  1004. .P
  1005. .RE
  1006. .RE
  1007. .P
  1008. If there are less than
  1009. .IR count
  1010. lines before the current line in the edit buffer, it shall be an
  1011. error.
  1012. .P
  1013. If used as a motion command:
  1014. .IP " 1." 4
  1015. The text region shall include the starting line and the previous
  1016. .IR count
  1017. lines.
  1018. .IP " 2." 4
  1019. Any text copied to a buffer shall be in line mode.
  1020. .P
  1021. If not used as a motion command:
  1022. .P
  1023. .IR "Current line" :
  1024. Set to
  1025. .IR "current line"
  1026. \-
  1027. .IR count .
  1028. .P
  1029. .IR "Current column" :
  1030. Set to non-\c
  1031. <blank>
  1032. for the
  1033. .BR \-
  1034. command; otherwise, unchanged.
  1035. .SS "Redraw Screen"
  1036. .IP "\fISynopsis\fR:" 10
  1037. .sp -1v
  1038. .RS 10 
  1039. .sp
  1040. .RS 4
  1041. .nf
  1043. <control>-R
  1044. .fi
  1045. .P
  1046. .RE
  1047. .RE
  1048. .P
  1049. If any lines have been deleted from the display screen and flagged as
  1050. deleted on the terminal using the
  1051. .BR @
  1052. convention (see the beginning of the EXTENDED DESCRIPTION section),
  1053. they shall be redisplayed to match the contents of the edit buffer.
  1054. .P
  1055. It is unspecified whether lines flagged with
  1056. .BR @
  1057. because they do not fit on the terminal display shall be affected.
  1058. .P
  1059. .IR "Current line" :
  1060. Unchanged.
  1061. .P
  1062. .IR "Current column" :
  1063. Unchanged.
  1064. .SS "Scroll Backward"
  1065. .IP "\fISynopsis\fR:" 10
  1066. .sp -1v
  1067. .RS 10 
  1068. .sp
  1069. .RS 4
  1070. .nf
  1072. \fB[\fIcount\fB]\fR <control>-U
  1073. .fi
  1074. .P
  1075. .RE
  1076. .RE
  1077. .P
  1078. If the current line is the first line of the edit buffer, it shall be
  1079. an error.
  1080. .P
  1081. If no
  1082. .IR count
  1083. is specified,
  1084. .IR count
  1085. shall default to the
  1086. .IR count
  1087. associated with the previous
  1088. <control>\(hyD
  1089. or
  1090. <control>\(hyU
  1091. command. If there was no previous
  1092. <control>\(hyD
  1093. or
  1094. <control>\(hyU
  1095. command,
  1096. .IR count
  1097. shall default to the value of the
  1098. .BR scroll
  1099. edit option.
  1100. .P
  1101. .IR "Current line" :
  1102. If
  1103. .IR count
  1104. is greater than the current line, set to 1; otherwise, set to the
  1105. current line \-
  1106. .IR count .
  1107. .P
  1108. .IR "Current column" :
  1109. Set to non-\c
  1110. <blank>.
  1111. .SS "Scroll Backward by Line"
  1112. .IP "\fISynopsis\fR:" 10
  1113. .sp -1v
  1114. .RS 10 
  1115. .sp
  1116. .RS 4
  1117. .nf
  1119. \fB[\fIcount\fB]\fR <control>-Y
  1120. .fi
  1121. .P
  1122. .RE
  1123. .RE
  1124. .P
  1125. Display the line
  1126. .IR count
  1127. lines before the first line currently displayed.
  1128. .P
  1129. If the current line is the first line of the edit buffer, it shall be
  1130. an error. If this calculation would result in a line that is before the
  1131. first line of the edit buffer, the first line of the display shall
  1132. display some portion of the first line of the edit buffer.
  1133. .P
  1134. .IR "Current line" :
  1135. Unchanged if the previous current character is displayed; otherwise,
  1136. set to the first line displayed.
  1137. .P
  1138. .IR "Current column" :
  1139. Unchanged.
  1140. .SS "Edit the Alternate File"
  1141. .IP "\fISynopsis\fR:" 10
  1142. .sp -1v
  1143. .RS 10 
  1144. .sp
  1145. .RS 4
  1146. .nf
  1148. <control>-\(ha
  1149. .fi
  1150. .P
  1151. .RE
  1152. .RE
  1153. This command shall be equivalent to the
  1154. .IR ex
  1155. .BR edit
  1156. command, with the alternate pathname as its argument.
  1157. .SS "Terminate Command or Input Mode"
  1158. .IP "\fISynopsis\fR:" 10
  1159. .sp -1v
  1160. .RS 10 
  1161. .sp
  1162. .RS 4
  1163. .nf
  1165. <ESC>
  1166. .fi
  1167. .P
  1168. .RE
  1169. .RE
  1170. .P
  1171. If a partial
  1172. .IR vi
  1173. command (as defined by at least one, non-\c
  1174. .IR count
  1175. character) has been entered, discard the
  1176. .IR count
  1177. and the command character(s).
  1178. .P
  1179. Otherwise, if no command characters have been entered, and the
  1180. <ESC>
  1181. was the result of a map expansion, the terminal shall be alerted and
  1182. the
  1183. <ESC>
  1184. character shall be discarded, but it shall not be an error.
  1185. .P
  1186. Otherwise, it shall be an error.
  1187. .P
  1188. .IR "Current line" :
  1189. Unchanged.
  1190. .P
  1191. .IR "Current column" :
  1192. Unchanged.
  1193. .SS "Search for tagstring"
  1194. .IP "\fISynopsis\fR:" 10
  1195. .sp -1v
  1196. .RS 10 
  1197. .sp
  1198. .RS 4
  1199. .nf
  1201. <control>-]
  1202. .fi
  1203. .P
  1204. .RE
  1205. .RE
  1206. .P
  1207. If the current character is not a word or
  1208. <blank>,
  1209. it shall be an error.
  1210. .P
  1211. This command shall be equivalent to the
  1212. .IR ex
  1213. .BR tag
  1214. command, with the argument to that command defined as follows.
  1215. .P
  1216. If the current character is a
  1217. <blank>:
  1218. .IP " 1." 4
  1219. Skip all
  1220. <blank>
  1221. characters after the cursor up to the end of the line.
  1222. .IP " 2." 4
  1223. If the end of the line is reached, it shall be an error.
  1224. .P
  1225. Then, the argument to the
  1226. .IR ex
  1227. .BR tag
  1228. command shall be the current character and all subsequent characters,
  1229. up to the first non-word character or the end of the line.
  1230. .SS "Move Cursor Forward"
  1231. .IP "\fISynopsis\fR:" 10
  1232. .sp -1v
  1233. .RS 10 
  1234. .sp
  1235. .RS 4
  1236. .nf
  1238. \fB[\fIcount\fB]\fR <space>
  1239. .br
  1240. \fB[\fIcount\fB]\fR l\fR  (ell)\fR
  1241. .fi
  1242. .P
  1243. .RE
  1244. .RE
  1245. .P
  1246. If there are less than
  1247. .IR count
  1248. non-\c
  1249. <newline>
  1250. characters after the cursor on the current line,
  1251. .IR count
  1252. shall be adjusted to the number of non-\c
  1253. <newline>
  1254. characters after the cursor on the line.
  1255. .P
  1256. If used as a motion command:
  1257. .IP " 1." 4
  1258. If the current or
  1259. .IR count th
  1260. character after the cursor is the last non-\c
  1261. <newline>
  1262. in the line, the text region shall be comprised of the current
  1263. character up to and including the last non-\c
  1264. <newline>
  1265. in the line. Otherwise, the text region shall be from the current
  1266. character up to, but not including, the
  1267. .IR count th
  1268. character after the cursor.
  1269. .IP " 2." 4
  1270. Any text copied to a buffer shall be in character mode.
  1271. .P
  1272. If not used as a motion command:
  1273. .P
  1274. If there are no non-\c
  1275. <newline>
  1276. characters after the current character on the current line, it shall be
  1277. an error.
  1278. .P
  1279. .IR "Current line" :
  1280. Unchanged.
  1281. .P
  1282. .IR "Current column" :
  1283. Set to the last column that displays any portion of the
  1284. .IR count th
  1285. character after the current character.
  1286. .SS "Replace Text with Results from Shell Command"
  1287. .IP "\fISynopsis\fR:" 10
  1288. .sp -1v
  1289. .RS 10 
  1290. .sp
  1291. .RS 4
  1292. .nf
  1294. \fB[\fIcount\fB]\fR ! \fImotion shell-commands\fR <newline>
  1295. .fi
  1296. .P
  1297. .RE
  1298. .RE
  1299. .P
  1300. If the motion command is the
  1301. .BR !
  1302. command repeated:
  1303. .IP " 1." 4
  1304. If the edit buffer is empty and no
  1305. .IR count
  1306. was supplied, the command shall be the equivalent of the
  1307. .IR ex
  1308. .BR :read
  1309. .BR !
  1310. command, with the text input, and no text shall be copied to any
  1311. buffer.
  1312. .IP " 2." 4
  1313. Otherwise:
  1314. .RS 4 
  1315. .IP " a." 4
  1316. If there are less than
  1317. .IR count
  1318. \-1 lines after the current line in the edit buffer, it shall be an
  1319. error.
  1320. .IP " b." 4
  1321. The text region shall be from the current line up to and including the
  1322. next
  1323. .IR count
  1324. \-1 lines.
  1325. .RE
  1326. .P
  1327. Otherwise, the text region shall be the lines in which any character of
  1328. the text region specified by the motion command appear.
  1329. .P
  1330. Any text copied to a buffer shall be in line mode.
  1331. .P
  1332. This command shall be equivalent to the
  1333. .IR ex
  1334. .BR !
  1335. command for the specified lines.
  1336. .SS "Move Cursor to End-of-Line"
  1337. .IP "\fISynopsis\fR:" 10
  1338. .sp -1v
  1339. .RS 10 
  1340. .sp
  1341. .RS 4
  1342. .nf
  1344. \fB[\fIcount\fB]\fR $
  1345. .fi
  1346. .P
  1347. .RE
  1348. .RE
  1349. .P
  1350. It shall be an error if there are less than (\c
  1351. .IR count
  1352. \-1) lines after the current line in the edit buffer.
  1353. .P
  1354. If used as a motion command:
  1355. .IP " 1." 4
  1356. If
  1357. .IR count
  1358. is 1:
  1359. .RS 4 
  1360. .IP " a." 4
  1361. It shall be an error if the line is empty.
  1362. .IP " b." 4
  1363. Otherwise, the text region shall consist of all characters from the
  1364. starting cursor to the last non-\c
  1365. <newline>
  1366. in the line, inclusive, and any text copied to a buffer shall be in
  1367. character mode.
  1368. .RE
  1369. .IP " 2." 4
  1370. Otherwise, if the starting cursor position is at or before the first
  1371. non-\c
  1372. <blank>
  1373. in the line, the text region shall consist of the current and the next
  1374. .IR count
  1375. \-1 lines, and any text saved to a buffer shall be in line mode.
  1376. .IP " 3." 4
  1377. Otherwise, the text region shall consist of all characters from the
  1378. starting cursor to the last non-\c
  1379. <newline>
  1380. in the line that is
  1381. .IR count
  1382. \-1 lines forward from the current line, and any text copied to a
  1383. buffer shall be in character mode.
  1384. .P
  1385. If not used as a motion command:
  1386. .P
  1387. .IR "Current line" :
  1388. Set to the
  1389. .IR "current line"
  1390. +
  1391. .IR count \-1.
  1392. .P
  1393. .IR "Current column" :
  1394. The current column is set to the last display line column of the last
  1395. non-\c
  1396. <newline>
  1397. in the line, or column position 1 if the line is empty.
  1398. .P
  1399. The current column shall be adjusted to be on the last display line
  1400. column of the last non-\c
  1401. <newline>
  1402. of the current line as subsequent commands change the current line,
  1403. until a command changes the current column.
  1404. .SS "Move to Matching Character"
  1405. .IP "\fISynopsis\fR:" 10
  1406. .sp -1v
  1407. .RS 10 
  1408. .sp
  1409. .RS 4
  1410. .nf
  1412. %
  1413. .fi
  1414. .P
  1415. .RE
  1416. .RE
  1417. .P
  1418. If the character at the current position is not a parenthesis, bracket,
  1419. or curly brace, search forward in the line to the first one of those
  1420. characters. If no such character is found, it shall be an error.
  1421. .P
  1422. The matching character shall be the parenthesis, bracket, or curly
  1423. brace matching the parenthesis, bracket, or curly brace, respectively,
  1424. that was at the current position or that was found on the current
  1425. line.
  1426. .P
  1427. Matching shall be determined as follows, for an open parenthesis:
  1428. .IP " 1." 4
  1429. Set a counter to 1.
  1430. .IP " 2." 4
  1431. Search forwards until a parenthesis is found or the end of the edit
  1432. buffer is reached.
  1433. .IP " 3." 4
  1434. If the end of the edit buffer is reached, it shall be an error.
  1435. .IP " 4." 4
  1436. If an open parenthesis is found, increment the counter by 1.
  1437. .IP " 5." 4
  1438. If a close parenthesis is found, decrement the counter by 1.
  1439. .IP " 6." 4
  1440. If the counter is zero, the current character is the matching
  1441. character.
  1442. .P
  1443. Matching for a close parenthesis shall be equivalent, except that the
  1444. search shall be backwards, from the starting character to the beginning
  1445. of the buffer, a close parenthesis shall increment the counter by 1,
  1446. and an open parenthesis shall decrement the counter by 1.
  1447. .P
  1448. Matching for brackets and curly braces shall be equivalent, except that
  1449. searching shall be done for open and close brackets or open and close
  1450. curly braces. It is implementation-defined whether other characters
  1451. are searched for and matched as well.
  1452. .P
  1453. If used as a motion command:
  1454. .IP " 1." 4
  1455. If the matching cursor was after the starting cursor in the edit
  1456. buffer, and the starting cursor position was at or before the first
  1457. non-\c
  1458. <blank>
  1459. non-\c
  1460. <newline>
  1461. in the starting line, and the matching cursor position was at or after
  1462. the last non-\c
  1463. <blank>
  1464. non-\c
  1465. <newline>
  1466. in the matching line, the text region shall consist of the current line
  1467. to the matching line, inclusive, and any text copied to a buffer shall
  1468. be in line mode.
  1469. .IP " 2." 4
  1470. If the matching cursor was before the starting cursor in the edit
  1471. buffer, and the starting cursor position was at or after the last
  1472. non-\c
  1473. <blank>
  1474. non-\c
  1475. <newline>
  1476. in the starting line, and the matching cursor position was at or before
  1477. the first non-\c
  1478. <blank>
  1479. non-\c
  1480. <newline>
  1481. in the matching line, the text region shall consist of the current line
  1482. to the matching line, inclusive, and any text copied to a buffer shall
  1483. be in line mode.
  1484. .IP " 3." 4
  1485. Otherwise, the text region shall consist of the starting character to
  1486. the matching character, inclusive, and any text copied to a buffer
  1487. shall be in character mode.
  1488. .P
  1489. If not used as a motion command:
  1490. .P
  1491. .IR "Current line" :
  1492. Set to the line where the matching character is located.
  1493. .P
  1494. .IR "Current column" :
  1495. Set to the last column where any portion of the matching character is
  1496. displayed.
  1497. .SS "Repeat Substitution"
  1498. .IP "\fISynopsis\fR:" 10
  1499. .sp -1v
  1500. .RS 10 
  1501. .sp
  1502. .RS 4
  1503. .nf
  1505. &
  1506. .fi
  1507. .P
  1508. .RE
  1509. .RE
  1510. .P
  1511. Repeat the previous substitution command. This command shall be
  1512. equivalent to the
  1513. .IR ex
  1514. .BR &
  1515. command with the current line as its addresses, and without
  1516. .IR options ,
  1517. .IR count ,
  1518. or
  1519. .IR flags .
  1520. .SS "Return to Previous Context at Beginning of Line"
  1521. .IP "\fISynopsis\fR:" 10
  1522. .sp -1v
  1523. .RS 10 
  1524. .sp
  1525. .RS 4
  1526. .nf
  1528. \&\(aq \fIcharacter\fR
  1529. .fi
  1530. .P
  1531. .RE
  1532. .RE
  1533. .P
  1534. It shall be an error if there is no line in the edit buffer marked by
  1535. .IR character .
  1536. .P
  1537. If used as a motion command:
  1538. .IP " 1." 4
  1539. If the starting cursor is after the marked cursor, then the locations
  1540. of the starting cursor and the marked cursor in the edit buffer shall
  1541. be logically swapped.
  1542. .IP " 2." 4
  1543. The text region shall consist of the starting line up to and including
  1544. the marked line, and any text copied to a buffer shall be in line
  1545. mode.
  1546. .P
  1547. If not used as a motion command:
  1548. .P
  1549. .IR "Current line" :
  1550. Set to the line referenced by the mark.
  1551. .P
  1552. .IR "Current column" :
  1553. Set to non-\c
  1554. <blank>.
  1555. .SS "Return to Previous Context"
  1556. .IP "\fISynopsis\fR:" 10
  1557. .sp -1v
  1558. .RS 10 
  1559. .sp
  1560. .RS 4
  1561. .nf
  1563. \&` \fIcharacter\fR
  1564. .fi
  1565. .P
  1566. .RE
  1567. .RE
  1568. .P
  1569. It shall be an error if the marked line is no longer in the edit
  1570. buffer. If the marked line no longer contains a character in the saved
  1571. numbered character position, it shall be as if the marked position is
  1572. the first non-\c
  1573. <blank>.
  1574. .P
  1575. If used as a motion command:
  1576. .IP " 1." 4
  1577. It shall be an error if the marked cursor references the same character
  1578. in the edit buffer as the starting cursor.
  1579. .IP " 2." 4
  1580. If the starting cursor is after the marked cursor, then the locations
  1581. of the starting cursor and the marked cursor in the edit buffer shall
  1582. be logically swapped.
  1583. .IP " 3." 4
  1584. If the starting line is empty or the starting cursor is at or before
  1585. the first non-\c
  1586. <blank>
  1587. non-\c
  1588. <newline>
  1589. of the starting line, and the marked cursor line is empty or the marked
  1590. cursor references the first character of the marked cursor line, the
  1591. text region shall consist of all lines containing characters from the
  1592. starting cursor to the line before the marked cursor line, inclusive,
  1593. and any text copied to a buffer shall be in line mode.
  1594. .IP " 4." 4
  1595. Otherwise, if the marked cursor line is empty or the marked cursor
  1596. references a character at or before the first non-\c
  1597. <blank>
  1598. non-\c
  1599. <newline>
  1600. of the marked cursor line, the region of text shall be from the
  1601. starting cursor to the last non-\c
  1602. <newline>
  1603. of the line before the marked cursor line, inclusive, and any text
  1604. copied to a buffer shall be in character mode.
  1605. .IP " 5." 4
  1606. Otherwise, the region of text shall be from the starting cursor
  1607. (inclusive), to the marked cursor (exclusive), and any text copied to a
  1608. buffer shall be in character mode.
  1609. .P
  1610. If not used as a motion command:
  1611. .P
  1612. .IR "Current line" :
  1613. Set to the line referenced by the mark.
  1614. .P
  1615. .IR "Current column" :
  1616. Set to the last column in which any portion of the character referenced
  1617. by the mark is displayed.
  1618. .SS "Return to Previous Section"
  1619. .IP "\fISynopsis\fR:" 10
  1620. .sp -1v
  1621. .RS 10 
  1622. .sp
  1623. .RS 4
  1624. .nf
  1626. \fB[\fIcount\fB]\fR [[
  1627. .fi
  1628. .P
  1629. .RE
  1630. .RE
  1631. .P
  1632. Move the cursor backward through the edit buffer to the first character
  1633. of the previous section boundary,
  1634. .IR count
  1635. times.
  1636. .P
  1637. If used as a motion command:
  1638. .IP " 1." 4
  1639. If the starting cursor was at the first character of the starting line
  1640. or the starting line was empty, and the first character of the boundary
  1641. was the first character of the boundary line, the text region shall
  1642. consist of the current line up to and including the line where the
  1643. .IR count th
  1644. next boundary starts, and any text copied to a buffer shall be in line
  1645. mode.
  1646. .IP " 2." 4
  1647. If the boundary was the last line of the edit buffer or the last non-\c
  1648. <newline>
  1649. of the last line of the edit buffer, the text region shall consist of
  1650. the last character in the edit buffer up to and including the starting
  1651. character, and any text saved to a buffer shall be in character mode.
  1652. .IP " 3." 4
  1653. Otherwise, the text region shall consist of the starting character up
  1654. to but not including the first character in the
  1655. .IR count th
  1656. next boundary, and any text copied to a buffer shall be in character
  1657. mode.
  1658. .P
  1659. If not used as a motion command:
  1660. .P
  1661. .IR "Current line" :
  1662. Set to the line where the
  1663. .IR count th
  1664. next boundary in the edit buffer starts.
  1665. .P
  1666. .IR "Current column" :
  1667. Set to the last column in which any portion of the first character of
  1668. the
  1669. .IR count th
  1670. next boundary is displayed, or column position 1 if the line is empty.
  1671. .SS "Move to Next Section"
  1672. .IP "\fISynopsis\fR:" 10
  1673. .sp -1v
  1674. .RS 10 
  1675. .sp
  1676. .RS 4
  1677. .nf
  1679. \fB[\fIcount\fB]\fR ]]
  1680. .fi
  1681. .P
  1682. .RE
  1683. .RE
  1684. .P
  1685. Move the cursor forward through the edit buffer to the first character
  1686. of the next section boundary,
  1687. .IR count
  1688. times.
  1689. .P
  1690. If used as a motion command:
  1691. .IP " 1." 4
  1692. If the starting cursor was at the first character of the starting line
  1693. or the starting line was empty, and the first character of the boundary
  1694. was the first character of the boundary line, the text region shall
  1695. consist of the current line up to and including the line where the
  1696. .IR count th
  1697. previous boundary starts, and any text copied to a buffer shall be in
  1698. line mode.
  1699. .IP " 2." 4
  1700. If the boundary was the first line of the edit buffer, the text region
  1701. shall consist of the first character in the edit buffer up to but not
  1702. including the starting character, and any text copied to a buffer shall
  1703. be in character mode.
  1704. .IP " 3." 4
  1705. Otherwise, the text region shall consist of the first character in the
  1706. .IR count th
  1707. previous section boundary up to but not including the starting
  1708. character, and any text copied to a buffer shall be in character mode.
  1709. .P
  1710. If not used as a motion command:
  1711. .P
  1712. .IR "Current line" :
  1713. Set to the line where the
  1714. .IR count th
  1715. previous boundary in the edit buffer starts.
  1716. .P
  1717. .IR "Current column" :
  1718. Set to the last column in which any portion of the first character of
  1719. the
  1720. .IR count th
  1721. previous boundary is displayed, or column position 1 if the line is
  1722. empty.
  1723. .SS "Move to First Non-<blank> Position on Current Line"
  1724. .IP "\fISynopsis\fR:" 10
  1725. .sp -1v
  1726. .RS 10 
  1727. .sp
  1728. .RS 4
  1729. .nf
  1731. \&\(ha
  1732. .fi
  1733. .P
  1734. .RE
  1735. .RE
  1736. If used as a motion command:
  1737. .IP " 1." 4
  1738. If the line has no non-\c
  1739. <blank>
  1740. non-\c
  1741. <newline>
  1742. characters, or if the cursor is at the first non-\c
  1743. <blank>
  1744. non-\c
  1745. <newline>
  1746. of the line, it shall be an error.
  1747. .IP " 2." 4
  1748. If the cursor is before the first non-\c
  1749. <blank>
  1750. non-\c
  1751. <newline>
  1752. of the line, the text region shall be comprised of the current
  1753. character, up to, but not including, the first non-\c
  1754. <blank>
  1755. non-\c
  1756. <newline>
  1757. of the line.
  1758. .IP " 3." 4
  1759. If the cursor is after the first non-\c
  1760. <blank>
  1761. non-\c
  1762. <newline>
  1763. of the line, the text region shall be from the character before the
  1764. starting cursor up to and including the first non-\c
  1765. <blank>
  1766. non-\c
  1767. <newline>
  1768. of the line.
  1769. .IP " 4." 4
  1770. Any text copied to a buffer shall be in character mode.
  1771. .P
  1772. If not used as a motion command:
  1773. .P
  1774. .IR "Current line" :
  1775. Unchanged.
  1776. .P
  1777. .IR "Current column" :
  1778. Set to non-\c
  1779. <blank>.
  1780. .SS "Current and Line Above"
  1781. .IP "\fISynopsis\fR:" 10
  1782. .sp -1v
  1783. .RS 10 
  1784. .sp
  1785. .RS 4
  1786. .nf
  1788. \fB[\fIcount\fB]\fR _
  1789. .fi
  1790. .P
  1791. .RE
  1792. .RE
  1793. .P
  1794. If there are less than
  1795. .IR count
  1796. \-1 lines after the current line in the edit buffer, it shall be an
  1797. error.
  1798. .P
  1799. If used as a motion command:
  1800. .IP " 1." 4
  1801. If
  1802. .IR count
  1803. is less than 2, the text region shall be the current line.
  1804. .IP " 2." 4
  1805. Otherwise, the text region shall include the starting line and the next
  1806. .IR count
  1807. \-1 lines.
  1808. .IP " 3." 4
  1809. Any text copied to a buffer shall be in line mode.
  1810. .P
  1811. If not used as a motion command:
  1812. .P
  1813. .IR "Current line" :
  1814. Set to current line +
  1815. .IR count
  1816. \-1.
  1817. .P
  1818. .IR "Current column" :
  1819. Set to non-\c
  1820. <blank>.
  1821. .SS "Move Back to Beginning of Sentence"
  1822. .IP "\fISynopsis\fR:" 10
  1823. .sp -1v
  1824. .RS 10 
  1825. .sp
  1826. .RS 4
  1827. .nf
  1829. \fB[\fIcount\fB]\fR (
  1830. .fi
  1831. .P
  1832. .RE
  1833. .RE
  1834. .P
  1835. Move backward to the beginning of a sentence. This command shall be
  1836. equivalent to the
  1837. .BR [[
  1838. command, with the exception that sentence boundaries shall be used
  1839. instead of section boundaries.
  1840. .SS "Move Forward to Beginning of Sentence"
  1841. .IP "\fISynopsis\fR:" 10
  1842. .sp -1v
  1843. .RS 10 
  1844. .sp
  1845. .RS 4
  1846. .nf
  1848. \fB[\fIcount\fB]\fR )
  1849. .fi
  1850. .P
  1851. .RE
  1852. .RE
  1853. .P
  1854. Move forward to the beginning of a sentence. This command shall be
  1855. equivalent to the
  1856. .BR ]]
  1857. command, with the exception that sentence boundaries shall be used
  1858. instead of section boundaries.
  1859. .SS "Move Back to Preceding Paragraph"
  1860. .IP "\fISynopsis\fR:" 10
  1861. .sp -1v
  1862. .RS 10 
  1863. .sp
  1864. .RS 4
  1865. .nf
  1867. \fB[\fIcount\fB]\fR {
  1868. .fi
  1869. .P
  1870. .RE
  1871. .RE
  1872. .P
  1873. Move back to the beginning of the preceding paragraph. This command
  1874. shall be equivalent to the
  1875. .BR [[
  1876. command, with the exception that paragraph boundaries shall be used
  1877. instead of section boundaries.
  1878. .SS "Move Forward to Next Paragraph"
  1879. .IP "\fISynopsis\fR:" 10
  1880. .sp -1v
  1881. .RS 10 
  1882. .sp
  1883. .RS 4
  1884. .nf
  1886. \fB[\fIcount\fB]\fR }
  1887. .fi
  1888. .P
  1889. .RE
  1890. .RE
  1891. .P
  1892. Move forward to the beginning of the next paragraph. This command
  1893. shall be equivalent to the
  1894. .BR ]]
  1895. command, with the exception that paragraph boundaries shall be used
  1896. instead of section boundaries.
  1897. .SS "Move to Specific Column Position"
  1898. .IP "\fISynopsis\fR:" 10
  1899. .sp -1v
  1900. .RS 10 
  1901. .sp
  1902. .RS 4
  1903. .nf
  1905. \fB[\fIcount\fB]\fR |
  1906. .fi
  1907. .P
  1908. .RE
  1909. .RE
  1910. .P
  1911. For the purposes of this command, lines that are too long for the
  1912. current display and that have been folded shall be treated as having a
  1913. single, 1\-based, number of columns.
  1914. .P
  1915. If there are less than
  1916. .IR count
  1917. columns in which characters from the current line are displayed on the
  1918. screen,
  1919. .IR count
  1920. shall be adjusted to be the last column in which any portion of the
  1921. line is displayed on the screen.
  1922. .P
  1923. If used as a motion command:
  1924. .IP " 1." 4
  1925. If the line is empty, or the cursor character is the same as the
  1926. character on the
  1927. .IR count th
  1928. column of the line, it shall be an error.
  1929. .IP " 2." 4
  1930. If the cursor is before the
  1931. .IR count th
  1932. column of the line, the text region shall be comprised of the current
  1933. character, up to but not including the character on the
  1934. .IR count th
  1935. column of the line.
  1936. .IP " 3." 4
  1937. If the cursor is after the
  1938. .IR count th
  1939. column of the line, the text region shall be from the character before
  1940. the starting cursor up to and including the character on the
  1941. .IR count th
  1942. column of the line.
  1943. .IP " 4." 4
  1944. Any text copied to a buffer shall be in character mode.
  1945. .P
  1946. If not used as a motion command:
  1947. .P
  1948. .IR "Current line" :
  1949. Unchanged.
  1950. .P
  1951. .IR "Current column" :
  1952. Set to the last column in which any portion of the character that is
  1953. displayed in the
  1954. .IR count
  1955. column of the line is displayed.
  1956. .SS "Reverse Find Character"
  1957. .IP "\fISynopsis\fR:" 10
  1958. .sp -1v
  1959. .RS 10 
  1960. .sp
  1961. .RS 4
  1962. .nf
  1964. \fB[\fIcount\fB]\fR ,
  1965. .fi
  1966. .P
  1967. .RE
  1968. .RE
  1969. .P
  1970. If the last
  1971. .BR F ,
  1972. .BR f ,
  1973. .BR T ,
  1974. or
  1975. .BR t
  1976. command was
  1977. .BR F ,
  1978. .BR f ,
  1979. .BR T ,
  1980. or
  1981. .BR t ,
  1982. this command shall be equivalent to an
  1983. .BR f ,
  1984. .BR F ,
  1985. .BR t ,
  1986. or
  1987. .BR T
  1988. command, respectively, with the specified
  1989. .IR count
  1990. and the same search character.
  1991. .P
  1992. If there was no previous
  1993. .BR F ,
  1994. .BR f ,
  1995. .BR T ,
  1996. or
  1997. .BR t
  1998. command, it shall be an error.
  1999. .SS "Repeat"
  2000. .IP "\fISynopsis\fR:" 10
  2001. .sp -1v
  2002. .RS 10 
  2003. .sp
  2004. .RS 4
  2005. .nf
  2007. \fB[\fIcount\fB]\fR .
  2008. .fi
  2009. .P
  2010. .RE
  2011. .RE
  2012. .P
  2013. Repeat the last
  2014. .BR ! ,
  2015. .BR < ,
  2016. .BR > ,
  2017. .BR A ,
  2018. .BR C ,
  2019. .BR D ,
  2020. .BR I ,
  2021. .BR J ,
  2022. .BR O ,
  2023. .BR P ,
  2024. .BR R ,
  2025. .BR S ,
  2026. .BR X ,
  2027. .BR Y ,
  2028. .BR a ,
  2029. .BR c ,
  2030. .BR d ,
  2031. .BR i ,
  2032. .BR o ,
  2033. .BR p ,
  2034. .BR r ,
  2035. .BR s ,
  2036. .BR x ,
  2037. .BR y ,
  2038. or
  2039. .BR ~
  2040. command. It shall be an error if none of these commands have been
  2041. executed. Commands (other than commands that enter text input mode)
  2042. executed as a result of map expansions, shall not change the value of
  2043. the last repeatable command.
  2044. .P
  2045. Repeated commands with associated motion commands shall repeat the
  2046. motion command as well; however, any specified
  2047. .IR count
  2048. shall replace the
  2049. .IR count (s)
  2050. that were originally specified to the repeated command or its
  2051. associated motion command.
  2052. .P
  2053. If the motion component of the repeated command is
  2054. .BR f ,
  2055. .BR F ,
  2056. .BR t ,
  2057. or
  2058. .BR T ,
  2059. the repeated command shall not set the remembered search character for
  2060. the
  2061. .BR ;
  2062. and
  2063. .BR ,
  2064. commands.
  2065. .P
  2066. If the repeated command is
  2067. .BR p
  2068. or
  2069. .BR P ,
  2070. and the buffer associated with that command was a numeric buffer named
  2071. with a number less than 9, the buffer associated with the repeated
  2072. command shall be set to be the buffer named by the name of the previous
  2073. buffer logically incremented by 1.
  2074. .P
  2075. If the repeated character is a text input command, the input text
  2076. associated with that command is repeated literally:
  2077. .IP " *" 4
  2078. Input characters are neither macro or abbreviation-expanded.
  2079. .IP " *" 4
  2080. Input characters are not interpreted in any special way with the
  2081. exception that
  2082. <newline>,
  2083. <carriage-return>,
  2084. and
  2085. <control>\(hyT
  2086. behave as described in
  2087. .IR "Input Mode Commands in vi".
  2088. .P
  2089. .IR "Current line" :
  2090. Set as described for the repeated command.
  2091. .P
  2092. .IR "Current column" :
  2093. Set as described for the repeated command.
  2094. .SS "Find Regular Expression"
  2095. .IP "\fISynopsis\fR:" 10
  2096. .sp -1v
  2097. .RS 10 
  2098. .sp
  2099. .RS 4
  2100. .nf
  2102. /
  2103. .fi
  2104. .P
  2105. .RE
  2106. .RE
  2107. .P
  2108. If the input line contains no non-\c
  2109. <newline>
  2110. characters, it shall be equivalent to a line containing only the
  2111. last regular expression encountered. The enhanced regular expressions
  2112. supported by
  2113. .IR vi
  2114. are described in
  2115. .IR "Regular Expressions in ex".
  2116. .P
  2117. Otherwise, the line shall be interpreted as one or more regular
  2118. expressions, optionally followed by an address offset or a
  2119. .IR vi
  2120. .BR z
  2121. command.
  2122. .P
  2123. If the regular expression is not the last regular expression on the
  2124. line, or if a line offset or
  2125. .BR z
  2126. command is specified, the regular expression shall be terminated by an
  2127. unescaped
  2128. .BR '/' 
  2129. character, which shall not be used as part of the regular expression.
  2130. If the regular expression is not the first regular expression on the
  2131. line, it shall be preceded by zero or more
  2132. <blank>
  2133. characters, a
  2134. <semicolon>,
  2135. zero or more
  2136. <blank>
  2137. characters, and a leading
  2138. .BR '/' 
  2139. character, which shall not be interpreted as part of the regular
  2140. expression. It shall be an error to precede any regular expression with
  2141. any characters other than these.
  2142. .P
  2143. Each search shall begin from the character after the first character of
  2144. the last match (or, if it is the first search, after the cursor). If
  2145. the
  2146. .BR wrapscan
  2147. edit option is set, the search shall continue to the character before
  2148. the starting cursor character; otherwise, to the end of the edit
  2149. buffer. It shall be an error if any search fails to find a match, and
  2150. an informational message to this effect shall be displayed.
  2151. .P
  2152. An optional address offset (see
  2153. .IR "Addressing in ex")
  2154. can be specified after the last regular expression by including a
  2155. trailing
  2156. .BR '/' 
  2157. character after the regular expression and specifying the address
  2158. offset. This offset will be from the line containing the match for the
  2159. last regular expression specified. It shall be an error if the line
  2160. offset would indicate a line address less than 1 or greater than the
  2161. last line in the edit buffer. An address offset of zero shall be
  2162. supported. It shall be an error to follow the address offset with any
  2163. other characters than
  2164. <blank>
  2165. characters.
  2166. .P
  2167. If not used as a motion command, an optional
  2168. .BR z
  2169. command (see
  2170. .IR "Redraw Window")
  2171. can be specified after the last regular expression by including a
  2172. trailing
  2173. .BR '/' 
  2174. character after the regular expression, zero or more
  2175. <blank>
  2176. characters, a
  2177. .BR 'z' ,
  2178. zero or more
  2179. <blank>
  2180. characters, an optional new
  2181. .BR window
  2182. edit option value, zero or more
  2183. <blank>
  2184. characters, and a location character. The effect shall be as if the
  2185. .BR z
  2186. command was executed after the
  2187. .BR /
  2188. command. It shall be an error to follow the
  2189. .BR z
  2190. command with any other characters than
  2191. <blank>
  2192. characters.
  2193. .P
  2194. The remembered search direction shall be set to forward.
  2195. .P
  2196. If used as a motion command:
  2197. .IP " 1." 4
  2198. It shall be an error if the last match references the same character in
  2199. the edit buffer as the starting cursor.
  2200. .IP " 2." 4
  2201. If any address offset is specified, the last match shall be adjusted by
  2202. the specified offset as described previously.
  2203. .IP " 3." 4
  2204. If the starting cursor is after the last match, then the locations of
  2205. the starting cursor and the last match in the edit buffer shall be
  2206. logically swapped.
  2207. .IP " 4." 4
  2208. If any address offset is specified, the text region shall consist of
  2209. all lines containing characters from the starting cursor to the last
  2210. match line, inclusive, and any text copied to a buffer shall be in line
  2211. mode.
  2212. .IP " 5." 4
  2213. Otherwise, if the starting line is empty or the starting cursor is at
  2214. or before the first non-\c
  2215. <blank>
  2216. non-\c
  2217. <newline>
  2218. of the starting line, and the last match line is empty or the last
  2219. match starts at the first character of the last match line, the text
  2220. region shall consist of all lines containing characters from the
  2221. starting cursor to the line before the last match line, inclusive, and
  2222. any text copied to a buffer shall be in line mode.
  2223. .IP " 6." 4
  2224. Otherwise, if the last match line is empty or the last match begins at
  2225. a character at or before the first non-\c
  2226. <blank>
  2227. non-\c
  2228. <newline>
  2229. of the last match line, the region of text shall be from the current
  2230. cursor to the last non-\c
  2231. <newline>
  2232. of the line before the last match line, inclusive, and any text copied
  2233. to a buffer shall be in character mode.
  2234. .IP " 7." 4
  2235. Otherwise, the region of text shall be from the current cursor
  2236. (inclusive), to the first character of the last match (exclusive), and
  2237. any text copied to a buffer shall be in character mode.
  2238. .P
  2239. If not used as a motion command:
  2240. .P
  2241. .IR "Current line" :
  2242. If a match is found, set to the last matched line plus the address
  2243. offset, if any; otherwise, unchanged.
  2244. .P
  2245. .IR "Current column" :
  2246. Set to the last column on which any portion of the first character in
  2247. the last matched string is displayed, if a match is found; otherwise,
  2248. unchanged.
  2249. .SS "Move to First Character in Line"
  2250. .IP "\fISynopsis\fR:" 10
  2251. .sp -1v
  2252. .RS 10 
  2253. .sp
  2254. .RS 4
  2255. .nf
  2257. 0  \fR(zero)\fR
  2258. .fi
  2259. .P
  2260. .RE
  2261. .RE
  2262. .P
  2263. Move to the first character on the current line. The character
  2264. .BR '0' 
  2265. shall not be interpreted as a command if it is immediately preceded by
  2266. a digit.
  2267. .P
  2268. If used as a motion command:
  2269. .IP " 1." 4
  2270. If the cursor character is the first character in the line, it shall be
  2271. an error.
  2272. .IP " 2." 4
  2273. The text region shall be from the character before the cursor character
  2274. up to and including the first character in the line.
  2275. .IP " 3." 4
  2276. Any text copied to a buffer shall be in character mode.
  2277. .P
  2278. If not used as a motion command:
  2279. .P
  2280. .IR "Current line" :
  2281. Unchanged.
  2282. .P
  2283. .IR "Current column" :
  2284. The last column in which any portion of the first character in the line
  2285. is displayed, or if the line is empty, unchanged.
  2286. .SS "Execute an ex Command"
  2287. .IP "\fISynopsis\fR:" 10
  2288. .sp -1v
  2289. .RS 10 
  2290. .sp
  2291. .RS 4
  2292. .nf
  2294. :
  2295. .fi
  2296. .P
  2297. .RE
  2298. .RE
  2299. .P
  2300. Execute one or more
  2301. .IR ex
  2302. commands.
  2303. .P
  2304. If any portion of the screen other than the last line of the screen was
  2305. overwritten by any
  2306. .IR ex
  2307. command (except
  2308. .BR shell ),
  2309. .IR vi
  2310. shall display a message indicating that it is waiting for an input from
  2311. the user, and shall then read a character. This action may also be
  2312. taken for other, unspecified reasons.
  2313. .P
  2314. If the next character entered is a
  2315. .BR ':' ,
  2316. another
  2317. .IR ex
  2318. command shall be accepted and executed. Any other character shall cause
  2319. the screen to be refreshed and
  2320. .IR vi
  2321. shall return to command mode.
  2322. .P
  2323. .IR "Current line" :
  2324. As specified for the
  2325. .IR ex
  2326. command.
  2327. .P
  2328. .IR "Current column" :
  2329. As specified for the
  2330. .IR ex
  2331. command.
  2332. .SS "Repeat Find"
  2333. .IP "\fISynopsis\fR:" 10
  2334. .sp -1v
  2335. .RS 10 
  2336. .sp
  2337. .RS 4
  2338. .nf
  2340. \fB[\fIcount\fB]\fR ;
  2341. .fi
  2342. .P
  2343. .RE
  2344. .RE
  2345. .P
  2346. This command shall be equivalent to the last
  2347. .BR F ,
  2348. .BR f ,
  2349. .BR T ,
  2350. or
  2351. .BR t
  2352. command, with the specified
  2353. .IR count ,
  2354. and with the same search character used for the last
  2355. .BR F ,
  2356. .BR f ,
  2357. .BR T ,
  2358. or
  2359. .BR t
  2360. command. If there was no previous
  2361. .BR F ,
  2362. .BR f ,
  2363. .BR T ,
  2364. or
  2365. .BR t
  2366. command, it shall be an error.
  2367. .SS "Shift Left"
  2368. .IP "\fISynopsis\fR:" 10
  2369. .sp -1v
  2370. .RS 10 
  2371. .sp
  2372. .RS 4
  2373. .nf
  2375. \fB[\fIcount\fB]\fR < \fImotion\fR
  2376. .fi
  2377. .P
  2378. .RE
  2379. .RE
  2380. .P
  2381. If the motion command is the
  2382. .BR <
  2383. command repeated:
  2384. .IP " 1." 4
  2385. If there are less than
  2386. .IR count
  2387. \-1 lines after the current line in the edit buffer, it shall be an
  2388. error.
  2389. .IP " 2." 4
  2390. The text region shall be from the current line, up to and including the
  2391. next
  2392. .IR count
  2393. \-1 lines.
  2394. .P
  2395. Shift any line in the text region specified by the
  2396. .IR count
  2397. and motion command one shiftwidth (see the
  2398. .IR ex
  2399. .BR shiftwidth
  2400. option) toward the start of the line, as described by the
  2401. .IR ex
  2402. .BR <
  2403. command. The unshifted lines shall be copied to the unnamed buffer in
  2404. line mode.
  2405. .P
  2406. .IR "Current line" :
  2407. If the motion was from the current cursor position toward the end of
  2408. the edit buffer, unchanged. Otherwise, set to the first line in the
  2409. edit buffer that is part of the text region specified by the motion
  2410. command.
  2411. .P
  2412. .IR "Current column" :
  2413. Set to non-\c
  2414. <blank>.
  2415. .SS "Shift Right"
  2416. .IP "\fISynopsis\fR:" 10
  2417. .sp -1v
  2418. .RS 10 
  2419. .sp
  2420. .RS 4
  2421. .nf
  2423. \fB[\fIcount\fB]\fR > \fImotion\fR
  2424. .fi
  2425. .P
  2426. .RE
  2427. .RE
  2428. .P
  2429. If the motion command is the
  2430. .BR >
  2431. command repeated:
  2432. .IP " 1." 4
  2433. If there are less than
  2434. .IR count
  2435. \-1 lines after the current line in the edit buffer, it shall be an
  2436. error.
  2437. .IP " 2." 4
  2438. The text region shall be from the current line, up to and including the
  2439. next
  2440. .IR count
  2441. \-1 lines.
  2442. .P
  2443. Shift any line with characters in the text region specified by the
  2444. .IR count
  2445. and motion command one shiftwidth (see the
  2446. .IR ex
  2447. .BR shiftwidth
  2448. option) away from the start of the line, as described by the
  2449. .IR ex
  2450. .BR >
  2451. command. The unshifted lines shall be copied into the unnamed buffer in
  2452. line mode.
  2453. .P
  2454. .IR "Current line" :
  2455. If the motion was from the current cursor position toward the end of
  2456. the edit buffer, unchanged. Otherwise, set to the first line in the
  2457. edit buffer that is part of the text region specified by the
  2458. motion command.
  2459. .P
  2460. .IR "Current column" :
  2461. Set to non-\c
  2462. <blank>.
  2463. .SS "Scan Backwards for Regular Expression"
  2464. .IP "\fISynopsis\fR:" 10
  2465. .sp -1v
  2466. .RS 10 
  2467. .sp
  2468. .RS 4
  2469. .nf
  2471. ?
  2472. .fi
  2473. .P
  2474. .RE
  2475. .RE
  2476. .P
  2477. Scan backwards; the
  2478. .BR ?
  2479. command shall be equivalent to the
  2480. .BR /
  2481. command (see
  2482. .IR "Find Regular Expression")
  2483. with the following exceptions:
  2484. .IP " 1." 4
  2485. The input prompt shall be a
  2486. .BR '?' .
  2487. .IP " 2." 4
  2488. Each search shall begin from the character before the first character
  2489. of the last match (or, if it is the first search, the character before
  2490. the cursor character).
  2491. .IP " 3." 4
  2492. The search direction shall be from the cursor toward the beginning of
  2493. the edit buffer, and the
  2494. .BR wrapscan
  2495. edit option shall affect whether the search wraps to the end of the
  2496. edit buffer and continues.
  2497. .IP " 4." 4
  2498. The remembered search direction shall be set to backward.
  2499. .SS "Execute"
  2500. .IP "\fISynopsis\fR:" 10
  2501. .sp -1v
  2502. .RS 10 
  2503. .sp
  2504. .RS 4
  2505. .nf
  2507. @\fIbuffer\fR
  2508. .fi
  2509. .P
  2510. .RE
  2511. .RE
  2512. .P
  2513. If the
  2514. .IR buffer
  2515. is specified as
  2516. .BR @ ,
  2517. the last buffer executed shall be used. If no previous buffer has been
  2518. executed, it shall be an error.
  2519. .P
  2520. Behave as if the contents of the named buffer were entered as standard
  2521. input. After each line of a line-mode buffer, and all but the last line
  2522. of a character mode buffer, behave as if a
  2523. <newline>
  2524. were entered as standard input.
  2525. .P
  2526. If an error occurs during this process, an error message shall be
  2527. written, and no more characters resulting from the execution of this
  2528. command shall be processed.
  2529. .P
  2530. If a
  2531. .IR count
  2532. is specified, behave as if that count were entered as user input before
  2533. the characters from the
  2534. .BR @
  2535. buffer were entered.
  2536. .P
  2537. .IR "Current line" :
  2538. As specified for the individual commands.
  2539. .P
  2540. .IR "Current column" :
  2541. As specified for the individual commands.
  2542. .SS "Reverse Case"
  2543. .IP "\fISynopsis\fR:" 10
  2544. .sp -1v
  2545. .RS 10 
  2546. .sp
  2547. .RS 4
  2548. .nf
  2550. \fB[\fIcount\fB]\fR \(ti
  2551. .fi
  2552. .P
  2553. .RE
  2554. .RE
  2555. .P
  2556. Reverse the case of the current character and the next
  2557. .IR count
  2558. \-1 characters, such that lowercase characters that have uppercase
  2559. counterparts shall be changed to uppercase characters, and uppercase
  2560. characters that have lowercase counterparts shall be changed to
  2561. lowercase characters, as prescribed by the current locale. No other
  2562. characters shall be affected by this command.
  2563. .P
  2564. If there are less than
  2565. .IR count
  2566. \-1 characters after the cursor in the edit buffer,
  2567. .IR count
  2568. shall be adjusted to the number of characters after the cursor in the
  2569. edit buffer minus 1.
  2570. .P
  2571. For the purposes of this command, the next character after the last
  2572. non-\c
  2573. <newline>
  2574. on the line shall be the next character in the edit buffer.
  2575. .P
  2576. .IR "Current line" :
  2577. Set to the line including the (\c
  2578. .IR count \-1)th
  2579. character after the cursor.
  2580. .P
  2581. .IR "Current column" :
  2582. Set to the last column in which any portion of the (\c
  2583. .IR count \-1)th
  2584. character after the cursor is displayed.
  2585. .SS "Append"
  2586. .IP "\fISynopsis\fR:" 10
  2587. .sp -1v
  2588. .RS 10 
  2589. .sp
  2590. .RS 4
  2591. .nf
  2593. \fB[\fIcount\fB]\fR a
  2594. .fi
  2595. .P
  2596. .RE
  2597. .RE
  2598. .P
  2599. Enter text input mode after the current cursor position. No characters
  2600. already in the edit buffer shall be affected by this command. A
  2601. .IR count
  2602. shall cause the input text to be appended
  2603. .IR count
  2604. \-1 more times to the end of the input.
  2605. .P
  2606. .IR "Current line/column" :
  2607. As specified for the text input commands (see
  2608. .IR "Input Mode Commands in vi").
  2609. .SS "Append at End-of-Line"
  2610. .IP "\fISynopsis\fR:" 10
  2611. .sp -1v
  2612. .RS 10 
  2613. .sp
  2614. .RS 4
  2615. .nf
  2617. \fB[\fIcount\fB]\fR A
  2618. .fi
  2619. .P
  2620. .RE
  2621. .RE
  2622. .P
  2623. This command shall be equivalent to the
  2624. .IR vi
  2625. command:
  2626. .sp
  2627. .RS 4
  2628. .nf
  2630. \fR$\fB [ \fIcount \fB]\fR a
  2631. .fi
  2632. .P
  2633. .RE
  2634. .P
  2635. (see
  2636. .IR "Append").
  2637. .SS "Move Backward to Preceding Word"
  2638. .IP "\fISynopsis\fR:" 10
  2639. .sp -1v
  2640. .RS 10 
  2641. .sp
  2642. .RS 4
  2643. .nf
  2645. \fB[\fIcount\fB]\fR b
  2646. .fi
  2647. .P
  2648. .RE
  2649. .RE
  2650. .P
  2651. With the exception that words are used as the delimiter instead of
  2652. bigwords, this command shall be equivalent to the
  2653. .BR B
  2654. command.
  2655. .SS "Move Backward to Preceding Bigword"
  2656. .IP "\fISynopsis\fR:" 10
  2657. .sp -1v
  2658. .RS 10 
  2659. .sp
  2660. .RS 4
  2661. .nf
  2663. \fB[\fIcount\fB]\fR B
  2664. .fi
  2665. .P
  2666. .RE
  2667. .RE
  2668. .P
  2669. If the edit buffer is empty or the cursor is on the first character of
  2670. the edit buffer, it shall be an error. If less than
  2671. .IR count
  2672. bigwords begin between the cursor and the start of the edit buffer,
  2673. .IR count
  2674. shall be adjusted to the number of bigword beginnings between the
  2675. cursor and the start of the edit buffer.
  2676. .P
  2677. If used as a motion command:
  2678. .IP " 1." 4
  2679. The text region shall be from the first character of the
  2680. .IR count th
  2681. previous bigword beginning up to but not including the cursor
  2682. character.
  2683. .IP " 2." 4
  2684. Any text copied to a buffer shall be in character mode.
  2685. .P
  2686. If not used as a motion command:
  2687. .P
  2688. .IR "Current line" :
  2689. Set to the line containing the
  2690. .IR "current column" .
  2691. .P
  2692. .IR "Current column" :
  2693. Set to the last column upon which any part of the first character of
  2694. the
  2695. .IR count th
  2696. previous bigword is displayed.
  2697. .SS "Change"
  2698. .IP "\fISynopsis\fR:" 10
  2699. .sp -1v
  2700. .RS 10 
  2701. .sp
  2702. .RS 4
  2703. .nf
  2705. \fB[\fIbuffer\fB][\fIcount\fB]\fR c \fImotion\fR
  2706. .fi
  2707. .P
  2708. .RE
  2709. .RE
  2710. .P
  2711. If the motion command is the
  2712. .BR c
  2713. command repeated:
  2714. .IP " 1." 4
  2715. The buffer text shall be in line mode.
  2716. .IP " 2." 4
  2717. If there are less than
  2718. .IR count
  2719. \-1 lines after the current line in the edit buffer, it shall be an
  2720. error.
  2721. .IP " 3." 4
  2722. The text region shall be from the current line up to and including the
  2723. next
  2724. .IR count
  2725. \-1 lines.
  2726. .P
  2727. Otherwise, the buffer text mode and text region shall be as specified
  2728. by the motion command.
  2729. .P
  2730. The replaced text shall be copied into
  2731. .IR buffer ,
  2732. if specified, and into the unnamed buffer. If the text to be replaced
  2733. contains characters from more than a single line, or the buffer text is
  2734. in line mode, the replaced text shall be copied into the numeric
  2735. buffers as well.
  2736. .P
  2737. If the buffer text is in line mode:
  2738. .IP " 1." 4
  2739. Any lines that contain characters in the region shall be deleted, and
  2740. the editor shall enter text input mode at the beginning of a new line
  2741. which shall replace the first line deleted.
  2742. .IP " 2." 4
  2743. If the
  2744. .BR autoindent
  2745. edit option is set,
  2746. .BR autoindent
  2747. characters equal to the
  2748. .BR autoindent
  2749. characters on the first line deleted shall be inserted as if entered by
  2750. the user.
  2751. .P
  2752. Otherwise, if characters from more than one line are in the region of
  2753. text:
  2754. .IP " 1." 4
  2755. The text shall be deleted.
  2756. .IP " 2." 4
  2757. Any text remaining in the last line in the text region shall be
  2758. appended to the first line in the region, and the last line in the
  2759. region shall be deleted.
  2760. .IP " 3." 4
  2761. The editor shall enter text input mode after the last character not
  2762. deleted from the first line in the text region, if any; otherwise, on
  2763. the first column of the first line in the region.
  2764. .br
  2765. .P
  2766. Otherwise:
  2767. .IP " 1." 4
  2768. If the glyph for
  2769. .BR '$' 
  2770. is smaller than the region, the end of the region shall be marked with
  2771. a
  2772. .BR '$' .
  2773. .IP " 2." 4
  2774. The editor shall enter text input mode, overwriting the region of
  2775. text.
  2776. .P
  2777. .IR "Current line/column" :
  2778. As specified for the text input commands (see
  2779. .IR "Input Mode Commands in vi").
  2780. .SS "Change to End-of-Line"
  2781. .IP "\fISynopsis\fR:" 10
  2782. .sp -1v
  2783. .RS 10 
  2784. .sp
  2785. .RS 4
  2786. .nf
  2788. \fB[\fIbuffer\fB][\fIcount\fB]\fR C
  2789. .fi
  2790. .P
  2791. .RE
  2792. .RE
  2793. .P
  2794. This command shall be equivalent to the
  2795. .IR vi
  2796. command:
  2797. .sp
  2798. .RS 4
  2799. .nf
  2801. \fB[\fIbuffer\fB][\fIcount\fB]\fR c$
  2802. .fi
  2803. .P
  2804. .RE
  2805. .P
  2806. See the
  2807. .BR c
  2808. command.
  2809. .SS "Delete"
  2810. .IP "\fISynopsis\fR:" 10
  2811. .sp -1v
  2812. .RS 10 
  2813. .sp
  2814. .RS 4
  2815. .nf
  2817. \fB[\fIbuffer\fB][\fIcount\fB]\fR d \fImotion\fR
  2818. .fi
  2819. .P
  2820. .RE
  2821. .RE
  2822. .P
  2823. If the motion command is the
  2824. .BR d
  2825. command repeated:
  2826. .IP " 1." 4
  2827. The buffer text shall be in line mode.
  2828. .IP " 2." 4
  2829. If there are less than
  2830. .IR count
  2831. \-1 lines after the current line in the edit buffer, it shall be an
  2832. error.
  2833. .IP " 3." 4
  2834. The text region shall be from the current line up to and including the
  2835. next
  2836. .IR count
  2837. \-1 lines.
  2838. .P
  2839. Otherwise, the buffer text mode and text region shall be as specified
  2840. by the motion command.
  2841. .P
  2842. If in open mode, and the current line is deleted, and the line remains
  2843. on the display, an
  2844. .BR '@' 
  2845. character shall be displayed as the first glyph of that line.
  2846. .P
  2847. Delete the region of text into
  2848. .IR buffer ,
  2849. if specified, and into the unnamed buffer. If the text to be deleted
  2850. contains characters from more than a single line, or the buffer text is
  2851. in line mode, the deleted text shall be copied into the numeric
  2852. buffers, as well.
  2853. .P
  2854. .IR "Current line" :
  2855. Set to the first text region line that appears in the edit buffer,
  2856. unless that line has been deleted, in which case it shall be set to the
  2857. last line in the edit buffer, or line 1 if the edit buffer is empty.
  2858. .P
  2859. .IR "Current column" :
  2860. .IP " 1." 4
  2861. If the line is empty, set to column position 1.
  2862. .IP " 2." 4
  2863. Otherwise, if the buffer text is in line mode or the motion was from
  2864. the cursor toward the end of the edit buffer:
  2865. .RS 4 
  2866. .IP " a." 4
  2867. If a character from the current line is displayed in the current
  2868. column, set to the last column that displays any portion of that
  2869. character.
  2870. .IP " b." 4
  2871. Otherwise, set to the last column in which any portion of any character
  2872. in the line is displayed.
  2873. .RE
  2874. .IP " 3." 4
  2875. Otherwise, if a character is displayed in the column that began the
  2876. text region, set to the last column that displays any portion of that
  2877. character.
  2878. .IP " 4." 4
  2879. Otherwise, set to the last column in which any portion of any character
  2880. in the line is displayed.
  2881. .SS "Delete to End-of-Line"
  2882. .IP "\fISynopsis\fR:" 10
  2883. .sp -1v
  2884. .RS 10 
  2885. .sp
  2886. .RS 4
  2887. .nf
  2889. \fB[\fIbuffer\fB]\fR D
  2890. .fi
  2891. .P
  2892. .RE
  2893. .RE
  2894. .P
  2895. Delete the text from the current position to the end of the current
  2896. line; equivalent to the
  2897. .IR vi
  2898. command:
  2899. .sp
  2900. .RS 4
  2901. .nf
  2903. \fB[\fIbuffer\fB]\fR d$
  2904. .fi
  2905. .P
  2906. .RE
  2907. .SS "Move to End-of-Word"
  2908. .IP "\fISynopsis\fR:" 10
  2909. .sp -1v
  2910. .RS 10 
  2911. .sp
  2912. .RS 4
  2913. .nf
  2915. \fB[\fIcount\fB]\fR e
  2916. .fi
  2917. .P
  2918. .RE
  2919. .RE
  2920. .P
  2921. With the exception that words are used instead of bigwords as the
  2922. delimiter, this command shall be equivalent to the
  2923. .BR E
  2924. command.
  2925. .SS "Move to End-of-Bigword"
  2926. .IP "\fISynopsis\fR:" 10
  2927. .sp -1v
  2928. .RS 10 
  2929. .sp
  2930. .RS 4
  2931. .nf
  2933. \fB[\fIcount\fB]\fR E
  2934. .fi
  2935. .P
  2936. .RE
  2937. .RE
  2938. .P
  2939. If the edit buffer is empty it shall be an error. If less than
  2940. .IR count
  2941. bigwords end between the cursor and the end of the edit buffer,
  2942. .IR count
  2943. shall be adjusted to the number of bigword endings between the cursor
  2944. and the end of the edit buffer.
  2945. .P
  2946. If used as a motion command:
  2947. .IP " 1." 4
  2948. The text region shall be from the last character of the
  2949. .IR count th
  2950. next bigword up to and including the cursor character.
  2951. .IP " 2." 4
  2952. Any text copied to a buffer shall be in character mode.
  2953. .P
  2954. If not used as a motion command:
  2955. .P
  2956. .IR "Current line" :
  2957. Set to the line containing the current column.
  2958. .P
  2959. .IR "Current column" :
  2960. Set to the last column upon which any part of the last character of the
  2961. .IR count th
  2962. next bigword is displayed.
  2963. .SS "Find Character in Current Line (Forward)"
  2964. .IP "\fISynopsis\fR:" 10
  2965. .sp -1v
  2966. .RS 10 
  2967. .sp
  2968. .RS 4
  2969. .nf
  2971. \fB[\fIcount\fB]\fR f \fIcharacter\fR
  2972. .fi
  2973. .P
  2974. .RE
  2975. .RE
  2976. .P
  2977. It shall be an error if
  2978. .IR count
  2979. occurrences of the character do not occur after the cursor in the
  2980. line.
  2981. .P
  2982. If used as a motion command:
  2983. .IP " 1." 4
  2984. The text range shall be from the cursor character up to and including
  2985. the
  2986. .IR count th
  2987. occurrence of the specified character after the cursor.
  2988. .IP " 2." 4
  2989. Any text copied to a buffer shall be in character mode.
  2990. .P
  2991. If not used as a motion command:
  2992. .P
  2993. .IR "Current line" :
  2994. Unchanged.
  2995. .P
  2996. .IR "Current column" :
  2997. Set to the last column in which any portion of the
  2998. .IR count th
  2999. occurrence of the specified character after the cursor appears in the
  3000. line.
  3001. .SS "Find Character in Current Line (Reverse)"
  3002. .IP "\fISynopsis\fR:" 10
  3003. .sp -1v
  3004. .RS 10 
  3005. .sp
  3006. .RS 4
  3007. .nf
  3009. \fB[\fIcount\fB]\fR F \fIcharacter\fR
  3010. .fi
  3011. .P
  3012. .RE
  3013. .RE
  3014. .P
  3015. It shall be an error if
  3016. .IR count
  3017. occurrences of the character do not occur before the cursor in the
  3018. line.
  3019. .P
  3020. If used as a motion command:
  3021. .IP " 1." 4
  3022. The text region shall be from the
  3023. .IR count th
  3024. occurrence of the specified character before the cursor, up to, but not
  3025. including the cursor character.
  3026. .IP " 2." 4
  3027. Any text copied to a buffer shall be in character mode.
  3028. .P
  3029. If not used as a motion command:
  3030. .P
  3031. .IR "Current line" :
  3032. Unchanged.
  3033. .P
  3034. .IR "Current column" :
  3035. Set to the last column in which any portion of the
  3036. .IR count th
  3037. occurrence of the specified character before the cursor appears in the
  3038. line.
  3039. .SS "Move to Line"
  3040. .IP "\fISynopsis\fR:" 10
  3041. .sp -1v
  3042. .RS 10 
  3043. .sp
  3044. .RS 4
  3045. .nf
  3047. \fB[\fIcount\fB]\fR G
  3048. .fi
  3049. .P
  3050. .RE
  3051. .RE
  3052. .P
  3053. If
  3054. .IR count
  3055. is not specified, it shall default to the last line of the edit buffer.
  3056. If
  3057. .IR count
  3058. is greater than the last line of the edit buffer, it shall be an
  3059. error.
  3060. .P
  3061. If used as a motion command:
  3062. .IP " 1." 4
  3063. The text region shall be from the cursor line up to and including the
  3064. specified line.
  3065. .IP " 2." 4
  3066. Any text copied to a buffer shall be in line mode.
  3067. .P
  3068. If not used as a motion command:
  3069. .P
  3070. .IR "Current line" :
  3071. Set to
  3072. .IR count
  3073. if
  3074. .IR count
  3075. is specified; otherwise, the last line.
  3076. .P
  3077. .IR "Current column" :
  3078. Set to non-\c
  3079. <blank>.
  3080. .SS "Move to Top of Screen"
  3081. .IP "\fISynopsis\fR:" 10
  3082. .sp -1v
  3083. .RS 10 
  3084. .sp
  3085. .RS 4
  3086. .nf
  3088. \fB[\fIcount\fB]\fR H
  3089. .fi
  3090. .P
  3091. .RE
  3092. .RE
  3093. .P
  3094. If the beginning of the line
  3095. .IR count
  3096. greater than the first line of which any portion appears on the display
  3097. does not exist, it shall be an error.
  3098. .P
  3099. If used as a motion command:
  3100. .IP " 1." 4
  3101. If in open mode, the text region shall be the current line.
  3102. .IP " 2." 4
  3103. Otherwise, the text region shall be from the starting line up to and
  3104. including (the first line of the display +
  3105. .IR count
  3106. \-1).
  3107. .IP " 3." 4
  3108. Any text copied to a buffer shall be in line mode.
  3109. .P
  3110. If not used as a motion command:
  3111. .P
  3112. If in open mode, this command shall set the current column to non-\c
  3113. <blank>
  3114. and do nothing else.
  3115. .P
  3116. Otherwise, it shall set the current line and current column as
  3117. follows.
  3118. .P
  3119. .IR "Current line" :
  3120. Set to (the first line of the display +
  3121. .IR count
  3122. \-1).
  3123. .P
  3124. .IR "Current column" :
  3125. Set to non-\c
  3126. <blank>.
  3127. .SS "Insert Before Cursor"
  3128. .IP "\fISynopsis\fR:" 10
  3129. .sp -1v
  3130. .RS 10 
  3131. .sp
  3132. .RS 4
  3133. .nf
  3135. \fB[\fIcount\fB]\fR i
  3136. .fi
  3137. .P
  3138. .RE
  3139. .RE
  3140. .P
  3141. Enter text input mode before the current cursor position. No characters
  3142. already in the edit buffer shall be affected by this command. A
  3143. .IR count
  3144. shall cause the input text to be appended
  3145. .IR count
  3146. \-1 more times to the end of the input.
  3147. .P
  3148. .IR "Current line/column" :
  3149. As specified for the text input commands (see
  3150. .IR "Input Mode Commands in vi").
  3151. .SS "Insert at Beginning of Line"
  3152. .IP "\fISynopsis\fR:" 10
  3153. .sp -1v
  3154. .RS 10 
  3155. .sp
  3156. .RS 4
  3157. .nf
  3159. \fB[\fIcount\fB]\fR I
  3160. .fi
  3161. .P
  3162. .RE
  3163. .RE
  3164. .P
  3165. This command shall be equivalent to the
  3166. .IR vi
  3167. command ^[\c
  3168. .IR count ]\c
  3169. .BR i .
  3170. .SS "Join"
  3171. .IP "\fISynopsis\fR:" 10
  3172. .sp -1v
  3173. .RS 10 
  3174. .sp
  3175. .RS 4
  3176. .nf
  3178. \fB[\fIcount\fB]\fR J
  3179. .fi
  3180. .P
  3181. .RE
  3182. .RE
  3183. .P
  3184. If the current line is the last line in the edit buffer, it shall be an
  3185. error.
  3186. .P
  3187. This command shall be equivalent to the
  3188. .IR ex
  3189. .BR join
  3190. command with no addresses, and an
  3191. .IR ex
  3192. command
  3193. .IR count
  3194. value of 1 if
  3195. .IR count
  3196. was not specified or if a
  3197. .IR count
  3198. of 1 was specified, and an
  3199. .IR ex
  3200. command
  3201. .IR count
  3202. value of
  3203. .IR count
  3204. \-1 for any other value of
  3205. .IR count ,
  3206. except that the current line and column shall be set as follows.
  3207. .P
  3208. .IR "Current line" :
  3209. Unchanged.
  3210. .P
  3211. .IR "Current column" :
  3212. The last column in which any portion of the character following the
  3213. last character in the initial line is displayed, or the last non-\c
  3214. <newline>
  3215. in the line if no characters were appended.
  3216. .SS "Move to Bottom of Screen"
  3217. .IP "\fISynopsis\fR:" 10
  3218. .sp -1v
  3219. .RS 10 
  3220. .sp
  3221. .RS 4
  3222. .nf
  3224. \fB[\fIcount\fB]\fR L
  3225. .fi
  3226. .P
  3227. .RE
  3228. .RE
  3229. .P
  3230. If the beginning of the line
  3231. .IR count
  3232. less than the last line of which any portion appears on the display
  3233. does not exist, it shall be an error.
  3234. .P
  3235. If used as a motion command:
  3236. .IP " 1." 4
  3237. If in open mode, the text region shall be the current line.
  3238. .IP " 2." 4
  3239. Otherwise, the text region shall include all lines from the starting
  3240. cursor line to (the last line of the display \-(\c
  3241. .IR count
  3242. \-1)).
  3243. .IP " 3." 4
  3244. Any text copied to a buffer shall be in line mode.
  3245. .P
  3246. If not used as a motion command:
  3247. .IP " 1." 4
  3248. If in open mode, this command shall set the current column to non-\c
  3249. <blank>
  3250. and do nothing else.
  3251. .IP " 2." 4
  3252. Otherwise, it shall set the current line and current column as follows.
  3253. .P
  3254. .IR "Current line" :
  3255. Set to (the last line of the display \-(\c
  3256. .IR count
  3257. \-1)).
  3258. .P
  3259. .IR "Current column" :
  3260. Set to non-\c
  3261. <blank>.
  3262. .SS "Mark Position"
  3263. .IP "\fISynopsis\fR:" 10
  3264. .sp -1v
  3265. .RS 10 
  3266. .sp
  3267. .RS 4
  3268. .nf
  3270. m \fIletter\fR
  3271. .fi
  3272. .P
  3273. .RE
  3274. .RE
  3275. .P
  3276. This command shall be equivalent to the
  3277. .IR ex
  3278. .BR mark
  3279. command with the specified character as an argument.
  3280. .SS "Move to Middle of Screen"
  3281. .IP "\fISynopsis\fR:" 10
  3282. .sp -1v
  3283. .RS 10 
  3284. .sp
  3285. .RS 4
  3286. .nf
  3288. M
  3289. .fi
  3290. .P
  3291. .RE
  3292. .RE
  3293. .P
  3294. The middle line of the display shall be calculated as follows:
  3295. .sp
  3296. .RS 4
  3297. .nf
  3299. (the top line of the display) + (((number of lines displayed) +1) /2) -1
  3300. .fi
  3301. .P
  3302. .RE
  3303. .P
  3304. If used as a motion command:
  3305. .IP " 1." 4
  3306. If in open mode, the text region shall be the current line.
  3307. .IP " 2." 4
  3308. Otherwise, the text region shall include all lines from the starting
  3309. cursor line up to and including the middle line of the display.
  3310. .IP " 3." 4
  3311. Any text copied to a buffer shall be in line mode.
  3312. .P
  3313. If not used as a motion command:
  3314. .P
  3315. If in open mode, this command shall set the current column to non-\c
  3316. <blank>
  3317. and do nothing else.
  3318. .P
  3319. Otherwise, it shall set the current line and current column as
  3320. follows.
  3321. .P
  3322. .IR "Current line" :
  3323. Set to the middle line of the display.
  3324. .P
  3325. .IR "Current column" :
  3326. Set to non-\c
  3327. <blank>.
  3328. .SS "Repeat Regular Expression Find (Forward)"
  3329. .IP "\fISynopsis\fR:" 10
  3330. .sp -1v
  3331. .RS 10 
  3332. .sp
  3333. .RS 4
  3334. .nf
  3336. n
  3337. .fi
  3338. .P
  3339. .RE
  3340. .RE
  3341. .P
  3342. If the remembered search direction was forward, the
  3343. .BR n
  3344. command shall be equivalent to the
  3345. .IR vi
  3346. .BR /
  3347. command with no characters entered by the user. Otherwise, it shall be
  3348. equivalent to the
  3349. .IR vi
  3350. .BR ?
  3351. command with no characters entered by the user.
  3352. .P
  3353. If the
  3354. .BR n
  3355. command is used as a motion command for the
  3356. .BR !
  3357. command, the editor shall not enter text input mode on the last line on
  3358. the screen, and shall behave as if the user entered a single
  3359. .BR '!' 
  3360. character as the text input.
  3361. .SS "Repeat Regular Expression Find (Reverse)"
  3362. .IP "\fISynopsis\fR:" 10
  3363. .sp -1v
  3364. .RS 10 
  3365. .sp
  3366. .RS 4
  3367. .nf
  3369. N
  3370. .fi
  3371. .P
  3372. .RE
  3373. .RE
  3374. .P
  3375. Scan for the next match of the last pattern given to
  3376. .BR /
  3377. or
  3378. .BR ? ,
  3379. but in the reverse direction; this is the reverse of
  3380. .BR n .
  3381. .P
  3382. If the remembered search direction was forward, the
  3383. .BR N
  3384. command shall be equivalent to the
  3385. .IR vi
  3386. .BR ?
  3387. command with no characters entered by the user. Otherwise, it shall be
  3388. equivalent to the
  3389. .IR vi
  3390. .BR /
  3391. command with no characters entered by the user. If the
  3392. .BR N
  3393. command is used as a motion command for the
  3394. .BR !
  3395. command, the editor shall not enter text input mode on the last line on
  3396. the screen, and shall behave as if the user entered a single
  3397. .BR !
  3398. character as the text input.
  3399. .SS "Insert Empty Line Below"
  3400. .IP "\fISynopsis\fR:" 10
  3401. .sp -1v
  3402. .RS 10 
  3403. .sp
  3404. .RS 4
  3405. .nf
  3407. o
  3408. .fi
  3409. .P
  3410. .RE
  3411. .RE
  3412. .P
  3413. Enter text input mode in a new line appended after the current line. A
  3414. .IR count
  3415. shall cause the input text to be appended
  3416. .IR count
  3417. \-1 more times to the end of the already added text, each time
  3418. starting on a new, appended line.
  3419. .P
  3420. .IR "Current line/column" :
  3421. As specified for the text input commands (see
  3422. .IR "Input Mode Commands in vi").
  3423. .SS "Insert Empty Line Above"
  3424. .IP "\fISynopsis\fR:" 10
  3425. .sp -1v
  3426. .RS 10 
  3427. .sp
  3428. .RS 4
  3429. .nf
  3431. O
  3432. .fi
  3433. .P
  3434. .RE
  3435. .RE
  3436. .P
  3437. Enter text input mode in a new line inserted before the current line. A
  3438. .IR count
  3439. shall cause the input text to be appended
  3440. .IR count
  3441. \-1 more times to the end of the already added text, each time
  3442. starting on a new, appended line.
  3443. .P
  3444. .IR "Current line/column" :
  3445. As specified for the text input commands (see
  3446. .IR "Input Mode Commands in vi").
  3447. .SS "Put from Buffer Following"
  3448. .IP "\fISynopsis\fR:" 10
  3449. .sp -1v
  3450. .RS 10 
  3451. .sp
  3452. .RS 4
  3453. .nf
  3455. \fB[\fIbuffer\fB]\fR p
  3456. .fi
  3457. .P
  3458. .RE
  3459. .RE
  3460. .P
  3461. If no
  3462. .IR buffer
  3463. is specified, the unnamed buffer shall be used.
  3464. .P
  3465. If the buffer text is in line mode, the text shall be appended below
  3466. the current line, and each line of the buffer shall become a new line
  3467. in the edit buffer. A
  3468. .IR count
  3469. shall cause the buffer text to be appended
  3470. .IR count
  3471. \-1 more times to the end of the already added text, each time
  3472. starting on a new, appended line.
  3473. .P
  3474. If the buffer text is in character mode, the text shall be appended
  3475. into the current line after the cursor, and each line of the buffer
  3476. other than the first and last shall become a new line in the edit
  3477. buffer. A
  3478. .IR count
  3479. shall cause the buffer text to be appended
  3480. .IR count
  3481. \-1 more times to the end of the already added text, each time
  3482. starting after the last added character.
  3483. .P
  3484. .IR "Current line" :
  3485. If the buffer text is in line mode, set the line to line +1; otherwise,
  3486. unchanged.
  3487. .P
  3488. .IR "Current column" :
  3489. If the buffer text is in line mode:
  3490. .IP " 1." 4
  3491. If there is a non-\c
  3492. <blank>
  3493. in the first line of the buffer, set to the last column on which any
  3494. portion of the first non-\c
  3495. <blank>
  3496. in the line is displayed.
  3497. .IP " 2." 4
  3498. If there is no non-\c
  3499. <blank>
  3500. in the first line of the buffer, set to the last column on which any
  3501. portion of the last non-\c
  3502. <newline>
  3503. in the first line of the buffer is displayed.
  3504. .P
  3505. If the buffer text is in character mode:
  3506. .IP " 1." 4
  3507. If the text in the buffer is from more than a single line, then set to
  3508. the last column on which any portion of the first character from the
  3509. buffer is displayed.
  3510. .IP " 2." 4
  3511. Otherwise, if the buffer is the unnamed buffer, set to the last column
  3512. on which any portion of the last character from the buffer is
  3513. displayed.
  3514. .IP " 3." 4
  3515. Otherwise, set to the first column on which any portion of the first
  3516. character from the buffer is displayed.
  3517. .SS "Put from Buffer Before"
  3518. .IP "\fISynopsis\fR:" 10
  3519. .sp -1v
  3520. .RS 10 
  3521. .sp
  3522. .RS 4
  3523. .nf
  3525. \fB[\fIbuffer\fB]\fR P
  3526. .fi
  3527. .P
  3528. .RE
  3529. .RE
  3530. .P
  3531. If no
  3532. .IR buffer
  3533. is specified, the unnamed buffer shall be used.
  3534. .P
  3535. If the buffer text is in line mode, the text shall be inserted above
  3536. the current line, and each line of the buffer shall become a new line
  3537. in the edit buffer. A
  3538. .IR count
  3539. shall cause the buffer text to be appended
  3540. .IR count
  3541. \-1 more times to the end of the already added text, each time
  3542. starting on a new, appended line.
  3543. .P
  3544. If the buffer text is in character mode, the text shall be inserted
  3545. into the current line before the cursor, and each line of the buffer
  3546. other than the first and last shall become a new line in the edit
  3547. buffer. A
  3548. .IR count
  3549. shall cause the buffer text to be appended
  3550. .IR count
  3551. \-1 more times to the end of the already added text, each time
  3552. starting after the last added character.
  3553. .P
  3554. .IR "Current line" :
  3555. Unchanged.
  3556. .P
  3557. .IR "Current column" :
  3558. If the buffer text is in line mode:
  3559. .IP " 1." 4
  3560. If there is a non-\c
  3561. <blank>
  3562. in the first line of the buffer, set to the last column on which any
  3563. portion of that character is displayed.
  3564. .IP " 2." 4
  3565. If there is no non-\c
  3566. <blank>
  3567. in the first line of the buffer, set to the last column on which any
  3568. portion of the last non-\c
  3569. <newline>
  3570. in the first line of the buffer is displayed.
  3571. .P
  3572. If the buffer text is in character mode:
  3573. .IP " 1." 4
  3574. If the text in the buffer is from more than a single line, then set to
  3575. the last column on which any portion of the first character from the
  3576. buffer is displayed.
  3577. .IP " 2." 4
  3578. Otherwise, if the buffer is the unnamed buffer, set to the last column
  3579. on which any portion of the last character from the buffer is displayed.
  3580. .IP " 3." 4
  3581. Otherwise, set to the first column on which any portion of the first
  3582. character from the buffer is displayed.
  3583. .SS "Enter ex Mode"
  3584. .IP "\fISynopsis\fR:" 10
  3585. .sp -1v
  3586. .RS 10 
  3587. .sp
  3588. .RS 4
  3589. .nf
  3591. Q
  3592. .fi
  3593. .P
  3594. .RE
  3595. .RE
  3596. .P
  3597. Leave visual or open mode and enter
  3598. .IR ex
  3599. command mode.
  3600. .P
  3601. .IR "Current line" :
  3602. Unchanged.
  3603. .P
  3604. .IR "Current column" :
  3605. Unchanged.
  3606. .SS "Replace Character"
  3607. .IP "\fISynopsis\fR:" 10
  3608. .sp -1v
  3609. .RS 10 
  3610. .sp
  3611. .RS 4
  3612. .nf
  3614. \fB[\fIcount\fB]\fR r \fIcharacter\fR
  3615. .fi
  3616. .P
  3617. .RE
  3618. .RE
  3619. .P
  3620. Replace the
  3621. .IR count
  3622. characters at and after the cursor with the specified character. If
  3623. there are less than
  3624. .IR count
  3625. non-\c
  3626. <newline>
  3627. characters at and after the cursor on the line, it shall be an error.
  3628. .P
  3629. If character is
  3630. <control>\(hyV,
  3631. any next character other than the
  3632. <newline>
  3633. shall be stripped of any special meaning and used as a literal
  3634. character.
  3635. .P
  3636. If character is
  3637. <ESC>,
  3638. no replacement shall be made and the current line and current column
  3639. shall be unchanged.
  3640. .P
  3641. If character is
  3642. <carriage-return>
  3643. or
  3644. <newline>,
  3645. .IR count
  3646. new lines shall be appended to the current line. All but the last of
  3647. these lines shall be empty.
  3648. .IR count
  3649. characters at and after the cursor shall be discarded, and any
  3650. remaining characters after the cursor in the current line shall be
  3651. moved to the last of the new lines. If the
  3652. .BR autoindent
  3653. edit option is set, they shall be preceded by the same number of
  3654. .BR autoindent
  3655. characters found on the line from which the command was executed.
  3656. .P
  3657. .IR "Current line" :
  3658. Unchanged unless the replacement character is a
  3659. <carriage-return>
  3660. or
  3661. <newline>,
  3662. in which case it shall be set to line +
  3663. .IR count .
  3664. .P
  3665. .IR "Current column" :
  3666. Set to the last column position on which a portion of the last replaced
  3667. character is displayed, or if the replacement character caused new
  3668. lines to be created, set to non-\c
  3669. <blank>.
  3670. .SS "Replace Characters"
  3671. .IP "\fISynopsis\fR:" 10
  3672. .sp -1v
  3673. .RS 10 
  3674. .sp
  3675. .RS 4
  3676. .nf
  3678. R
  3679. .fi
  3680. .P
  3681. .RE
  3682. .RE
  3683. .P
  3684. Enter text input mode at the current cursor position possibly
  3685. replacing text on the current line. A
  3686. .IR count
  3687. shall cause the input text to be appended
  3688. .IR count
  3689. \-1 more times to the end of the input.
  3690. .P
  3691. .IR "Current line/column" :
  3692. As specified for the text input commands (see
  3693. .IR "Input Mode Commands in vi").
  3694. .SS "Substitute Character"
  3695. .IP "\fISynopsis\fR:" 10
  3696. .sp -1v
  3697. .RS 10 
  3698. .sp
  3699. .RS 4
  3700. .nf
  3702. \fB[\fIbuffer\fB][\fIcount\fB]\fR s
  3703. .fi
  3704. .P
  3705. .RE
  3706. .RE
  3707. .P
  3708. This command shall be equivalent to the
  3709. .IR vi
  3710. command:
  3711. .sp
  3712. .RS 4
  3713. .nf
  3715. \fB[\fIbuffer\fB][\fIcount\fB]\fR c<space>
  3716. .fi
  3717. .P
  3718. .RE
  3719. .SS "Substitute Lines"
  3720. .IP "\fISynopsis\fR:" 10
  3721. .sp -1v
  3722. .RS 10 
  3723. .sp
  3724. .RS 4
  3725. .nf
  3727. \fB[\fIbuffer\fB][\fIcount\fB]\fR S
  3728. .fi
  3729. .P
  3730. .RE
  3731. .RE
  3732. .P
  3733. This command shall be equivalent to the
  3734. .IR vi
  3735. command:
  3736. .sp
  3737. .RS 4
  3738. .nf
  3740. \fB[\fIbuffer\fB][\fIcount\fB]\fR c_
  3741. .fi
  3742. .P
  3743. .RE
  3744. .SS "Move Cursor to Before Character (Forward)"
  3745. .IP "\fISynopsis\fR:" 10
  3746. .sp -1v
  3747. .RS 10 
  3748. .sp
  3749. .RS 4
  3750. .nf
  3752. \fB[\fIcount\fB]\fR t \fIcharacter\fR
  3753. .fi
  3754. .P
  3755. .RE
  3756. .RE
  3757. .P
  3758. It shall be an error if
  3759. .IR count
  3760. occurrences of the character do not occur after the cursor in the
  3761. line.
  3762. .P
  3763. If used as a motion command:
  3764. .IP " 1." 4
  3765. The text region shall be from the cursor up to but not including the
  3766. .IR count th
  3767. occurrence of the specified character after the cursor.
  3768. .IP " 2." 4
  3769. Any text copied to a buffer shall be in character mode.
  3770. .P
  3771. If not used as a motion command:
  3772. .P
  3773. .IR "Current line" :
  3774. Unchanged.
  3775. .P
  3776. .IR "Current column" :
  3777. Set to the last column in which any portion of the character before the
  3778. .IR count th
  3779. occurrence of the specified character after the cursor appears in the
  3780. line.
  3781. .SS "Move Cursor to After Character (Reverse)"
  3782. .IP "\fISynopsis\fR:" 10
  3783. .sp -1v
  3784. .RS 10 
  3785. .sp
  3786. .RS 4
  3787. .nf
  3789. \fB[\fIcount\fB]\fR T \fIcharacter\fR
  3790. .fi
  3791. .P
  3792. .RE
  3793. .RE
  3794. .P
  3795. It shall be an error if
  3796. .IR count
  3797. occurrences of the character do not occur before the cursor in the
  3798. line.
  3799. .P
  3800. If used as a motion command:
  3801. .IP " 1." 4
  3802. If the character before the cursor is the specified character, it shall
  3803. be an error.
  3804. .IP " 2." 4
  3805. The text region shall be from the character before the cursor up to but
  3806. not including the
  3807. .IR count th
  3808. occurrence of the specified character before the cursor.
  3809. .IP " 3." 4
  3810. Any text copied to a buffer shall be in character mode.
  3811. .P
  3812. If not used as a motion command:
  3813. .P
  3814. .IR "Current line" :
  3815. Unchanged.
  3816. .P
  3817. .IR "Current column" :
  3818. Set to the last column in which any portion of the character after the
  3819. .IR count th
  3820. occurrence of the specified character before the cursor appears in the
  3821. line.
  3822. .SS "Undo"
  3823. .IP "\fISynopsis\fR:" 10
  3824. .sp -1v
  3825. .RS 10 
  3826. .sp
  3827. .RS 4
  3828. .nf
  3830. u
  3831. .fi
  3832. .P
  3833. .RE
  3834. .RE
  3835. .P
  3836. This command shall be equivalent to the
  3837. .IR ex
  3838. .BR undo
  3839. command except that the current line and current column shall be set as
  3840. follows:
  3841. .P
  3842. .IR "Current line" :
  3843. Set to the first line added or changed if any; otherwise, move to the
  3844. line preceding any deleted text if one exists; otherwise, move to line 1.
  3845. .P
  3846. .IR "Current column" :
  3847. If undoing an
  3848. .IR ex
  3849. command, set to the first non-\c
  3850. <blank>.
  3851. .P
  3852. Otherwise, if undoing a text input command:
  3853. .IP " 1." 4
  3854. If the command was a
  3855. .BR C ,
  3856. .BR c ,
  3857. .BR O ,
  3858. .BR o ,
  3859. .BR R ,
  3860. .BR S ,
  3861. or
  3862. .BR s
  3863. command, the current column shall be set to the value it held when the
  3864. text input command was entered.
  3865. .IP " 2." 4
  3866. Otherwise, set to the last column in which any portion of the first
  3867. character after the deleted text is displayed, or, if no non-\c
  3868. <newline>
  3869. characters follow the text deleted from this line, set to the last column
  3870. in which any portion of the last non-\c
  3871. <newline>
  3872. in the line is displayed, or 1 if the line is empty.
  3873. .P
  3874. Otherwise, if a single line was modified (that is, not added or
  3875. deleted) by the
  3876. .BR u
  3877. command:
  3878. .IP " 1." 4
  3879. If text was added or changed, set to the last column in which any
  3880. portion of the first character added or changed is displayed.
  3881. .IP " 2." 4
  3882. If text was deleted, set to the last column in which any portion of the
  3883. first character after the deleted text is displayed, or, if no non-\c
  3884. <newline>
  3885. characters follow the deleted text, set to the last column in which any
  3886. portion of the last non-\c
  3887. <newline>
  3888. in the line is displayed, or 1 if the line is empty.
  3889. .P
  3890. Otherwise, set to non-\c
  3891. <blank>.
  3892. .SS "Undo Current Line"
  3893. .IP "\fISynopsis\fR:" 10
  3894. .sp -1v
  3895. .RS 10 
  3896. .sp
  3897. .RS 4
  3898. .nf
  3900. U
  3901. .fi
  3902. .P
  3903. .RE
  3904. .RE
  3905. .P
  3906. Restore the current line to its state immediately before the most
  3907. recent time that it became the current line.
  3908. .P
  3909. .IR "Current line" :
  3910. Unchanged.
  3911. .P
  3912. .IR "Current column" :
  3913. Set to the first column in the line in which any portion of the first
  3914. character in the line is displayed.
  3915. .SS "Move to Beginning of Word"
  3916. .IP "\fISynopsis\fR:" 10
  3917. .sp -1v
  3918. .RS 10 
  3919. .sp
  3920. .RS 4
  3921. .nf
  3923. \fB[\fIcount\fB]\fR w
  3924. .fi
  3925. .P
  3926. .RE
  3927. .RE
  3928. .P
  3929. With the exception that words are used as the delimiter instead of
  3930. bigwords, this command shall be equivalent to the
  3931. .BR W
  3932. command.
  3933. .SS "Move to Beginning of Bigword"
  3934. .IP "\fISynopsis\fR:" 10
  3935. .sp -1v
  3936. .RS 10 
  3937. .sp
  3938. .RS 4
  3939. .nf
  3941. \fB[\fIcount\fB]\fR W
  3942. .fi
  3943. .P
  3944. .RE
  3945. .RE
  3946. .P
  3947. If the edit buffer is empty, it shall be an error. If there are less
  3948. than
  3949. .IR count
  3950. bigwords between the cursor and the end of the edit buffer,
  3951. .IR count
  3952. shall be adjusted to move the cursor to the last bigword in the edit
  3953. buffer.
  3954. .P
  3955. If used as a motion command:
  3956. .IP " 1." 4
  3957. If the associated command is
  3958. .BR c ,
  3959. .IR count
  3960. is 1, and the cursor is on a
  3961. <blank>,
  3962. the region of text shall be the current character and no further action
  3963. shall be taken.
  3964. .IP " 2." 4
  3965. If there are less than
  3966. .IR count
  3967. bigwords between the cursor and the end of the edit buffer, then the
  3968. command shall succeed, and the region of text shall include the last
  3969. character of the edit buffer.
  3970. .IP " 3." 4
  3971. If there are
  3972. <blank>
  3973. characters or an end-of-line that precede the
  3974. .IR count th
  3975. bigword, and the associated command is
  3976. .BR c ,
  3977. the region of text shall be up to and including the last character
  3978. before the preceding
  3979. <blank>
  3980. characters or end-of-line.
  3981. .IP " 4." 4
  3982. If there are
  3983. <blank>
  3984. characters or an end-of-line that precede the bigword, and the associated
  3985. command is
  3986. .BR d
  3987. or
  3988. .BR y ,
  3989. the region of text shall be up to and including the last
  3990. <blank>
  3991. before the start of the bigword or end-of-line.
  3992. .IP " 5." 4
  3993. Any text copied to a buffer shall be in character mode.
  3994. .P
  3995. If not used as a motion command:
  3996. .IP " 1." 4
  3997. If the cursor is on the last character of the edit buffer, it shall be
  3998. an error.
  3999. .P
  4000. .IR "Current line" :
  4001. Set to the line containing the current column.
  4002. .P
  4003. .IR "Current column" :
  4004. Set to the last column in which any part of the first character of the
  4005. .IR count th
  4006. next bigword is displayed.
  4007. .SS "Delete Character at Cursor"
  4008. .IP "\fISynopsis\fR:" 10
  4009. .sp -1v
  4010. .RS 10 
  4011. .sp
  4012. .RS 4
  4013. .nf
  4015. \fB[\fIbuffer\fB][\fIcount\fB]\fR x
  4016. .fi
  4017. .P
  4018. .RE
  4019. .RE
  4020. .P
  4021. Delete the
  4022. .IR count
  4023. characters at and after the current character into
  4024. .IR buffer ,
  4025. if specified, and into the unnamed buffer.
  4026. .P
  4027. If the line is empty, it shall be an error. If there are less than
  4028. .IR count
  4029. non-\c
  4030. <newline>
  4031. characters at and after the cursor on the current line,
  4032. .IR count
  4033. shall be adjusted to the number of non-\c
  4034. <newline>
  4035. characters at and after the cursor.
  4036. .P
  4037. .IR "Current line" :
  4038. Unchanged.
  4039. .P
  4040. .IR "Current column" :
  4041. If the line is empty, set to column position 1. Otherwise, if there
  4042. were
  4043. .IR count
  4044. or less non-\c
  4045. <newline>
  4046. characters at and after the cursor on the current line, set to the last
  4047. column that displays any part of the last non-\c
  4048. <newline>
  4049. of the line. Otherwise, unchanged.
  4050. .SS "Delete Character Before Cursor"
  4051. .IP "\fISynopsis\fR:" 10
  4052. .sp -1v
  4053. .RS 10 
  4054. .sp
  4055. .RS 4
  4056. .nf
  4058. \fB[\fIbuffer\fB][\fIcount\fB]\fR X
  4059. .fi
  4060. .P
  4061. .RE
  4062. .RE
  4063. .P
  4064. Delete the
  4065. .IR count
  4066. characters before the current character into
  4067. .IR buffer ,
  4068. if specified, and into the unnamed buffer.
  4069. .P
  4070. If there are no characters before the current character on the current
  4071. line, it shall be an error. If there are less than
  4072. .IR count
  4073. previous characters on the current line,
  4074. .IR count
  4075. shall be adjusted to the number of previous characters on the line.
  4076. .P
  4077. .IR "Current line" :
  4078. Unchanged.
  4079. .P
  4080. .IR "Current column" :
  4081. Set to (current column \- the width of the deleted characters).
  4082. .SS "Yank"
  4083. .IP "\fISynopsis\fR:" 10
  4084. .sp -1v
  4085. .RS 10 
  4086. .sp
  4087. .RS 4
  4088. .nf
  4090. \fB[\fIbuffer\fB][\fIcount\fB]\fR y \fImotion\fR
  4091. .fi
  4092. .P
  4093. .RE
  4094. .RE
  4095. .P
  4096. Copy (yank) the region of text into
  4097. .IR buffer ,
  4098. if specified, and into the unnamed buffer.
  4099. .P
  4100. If the motion command is the
  4101. .BR y
  4102. command repeated:
  4103. .IP " 1." 4
  4104. The buffer shall be in line mode.
  4105. .IP " 2." 4
  4106. If there are less than
  4107. .IR count
  4108. \-1 lines after the current line in the edit buffer, it shall be an
  4109. error.
  4110. .IP " 3." 4
  4111. The text region shall be from the current line up to and including the
  4112. next
  4113. .IR count
  4114. \-1 lines.
  4115. .P
  4116. Otherwise, the buffer text mode and text region shall be as specified
  4117. by the motion command.
  4118. .P
  4119. .IR "Current line" :
  4120. If the motion was from the current cursor position toward the end of
  4121. the edit buffer, unchanged. Otherwise, set to the first line in the
  4122. edit buffer that is part of the text region specified by the
  4123. motion command.
  4124. .P
  4125. .IR "Current column" :
  4126. .IP " 1." 4
  4127. If the motion was from the current cursor position toward the end of
  4128. the edit buffer, unchanged.
  4129. .IP " 2." 4
  4130. Otherwise, if the current line is empty, set to column position 1.
  4131. .IP " 3." 4
  4132. Otherwise, set to the last column that displays any part of the first
  4133. character in the file that is part of the text region specified by the
  4134. motion command.
  4135. .SS "Yank Current Line"
  4136. .IP "\fISynopsis\fR:" 10
  4137. .sp -1v
  4138. .RS 10 
  4139. .sp
  4140. .RS 4
  4141. .nf
  4143. \fB[\fIbuffer\fB][\fIcount\fB]\fR Y
  4144. .fi
  4145. .P
  4146. .RE
  4147. .RE
  4148. .P
  4149. This command shall be equivalent to the
  4150. .IR vi
  4151. command:
  4152. .sp
  4153. .RS 4
  4154. .nf
  4156. \fB[\fIbuffer\fB][\fIcount\fB]\fR y_
  4157. .fi
  4158. .P
  4159. .RE
  4160. .SS "Redraw Window"
  4161. .P
  4162. If in open mode, the
  4163. .BR z
  4164. command shall have the Synopsis:
  4165. .IP "\fISynopsis\fR:" 10
  4166. .sp -1v
  4167. .RS 10 
  4168. .sp
  4169. .RS 4
  4170. .nf
  4172. \fB[\fIcount\fB]\fR z
  4173. .fi
  4174. .P
  4175. .RE
  4176. .RE
  4177. .P
  4178. If
  4179. .IR count
  4180. is not specified, it shall default to the
  4181. .BR window
  4182. edit option \-1. The
  4183. .BR z
  4184. command shall be equivalent to the
  4185. .IR ex
  4186. .BR z
  4187. command, with a type character of
  4188. .BR =
  4189. and a
  4190. .IR count
  4191. of
  4192. .IR count
  4193. \-2, except that the current line and current column shall be set as
  4194. follows, and the
  4195. .BR window
  4196. edit option shall not be affected. If the calculation for the
  4197. .IR count
  4198. argument would result in a negative number, the
  4199. .IR count
  4200. argument to the
  4201. .IR ex
  4202. .BR z
  4203. command shall be zero. A blank line shall be written after the last
  4204. line is written.
  4205. .P
  4206. .IR "Current line" :
  4207. Unchanged.
  4208. .P
  4209. .IR "Current column" :
  4210. Unchanged.
  4211. .P
  4212. If not in open mode, the
  4213. .BR z
  4214. command shall have the following Synopsis:
  4215. .IP "\fISynopsis\fR:" 10
  4216. .sp -1v
  4217. .RS 10 
  4218. .sp
  4219. .RS 4
  4220. .nf
  4222. \fB[\fIline\fB]\fR z \fB[\fIcount\fB] \fIcharacter\fR
  4223. .fi
  4224. .P
  4225. .RE
  4226. .RE
  4227. .P
  4228. If
  4229. .IR line
  4230. is not specified, it shall default to the current line. If
  4231. .IR line
  4232. is specified, but is greater than the number of lines in the edit
  4233. buffer, it shall default to the number of lines in the edit buffer.
  4234. .P
  4235. If
  4236. .IR count
  4237. is specified, the value of the
  4238. .BR window
  4239. edit option shall be set to
  4240. .IR count
  4241. (as described in the
  4242. .IR ex
  4243. .BR window
  4244. command), and the screen shall be redrawn.
  4245. .P
  4246. .IR line
  4247. shall be placed as specified by the following characters:
  4248. .IP "<newline>,\ <carriage-return>" 6
  4249. .br
  4250. Place the beginning of the line on the first line of the display.
  4251. .IP "\fR.\fP" 6
  4252. Place the beginning of the line in the center of the display. The
  4253. middle line of the display shall be calculated as described for the
  4254. .BR M
  4255. command.
  4256. .IP "\fR\-\fP" 6
  4257. Place an unspecified portion of the line on the last line of the
  4258. display.
  4259. .IP "\fR+\fP" 6
  4260. If
  4261. .IR line
  4262. was specified, equivalent to the
  4263. <newline>
  4264. case. If
  4265. .IR line
  4266. was not specified, display a screen where the first line of the display
  4267. shall be (current last line) +1. If there are no lines after the last
  4268. line in the display, it shall be an error.
  4269. .IP "\fR^\fP" 6
  4270. If
  4271. .IR line
  4272. was specified, display a screen where the last line of the display
  4273. shall contain an unspecified portion of the first line of a display
  4274. that had an unspecified portion of the specified line on the last line
  4275. of the display. If this calculation results in a line before the
  4276. beginning of the edit buffer, display the first screen of the edit
  4277. buffer.
  4278. .RS 6 
  4279. .P
  4280. Otherwise, display a screen where the last line of the display shall
  4281. contain an unspecified portion of (current first line \-1). If this
  4282. calculation results in a line before the beginning of the edit buffer,
  4283. it shall be an error.
  4284. .RE
  4285. .br
  4286. .P
  4287. .IR "Current line" :
  4288. If
  4289. .IR line
  4290. and the
  4291. .BR '\(ha' 
  4292. character were specified:
  4293. .IP " 1." 4
  4294. If the first screen was displayed as a result of the command attempting
  4295. to display lines before the beginning of the edit buffer: if the first
  4296. screen was already displayed, unchanged; otherwise, set to (current
  4297. first line \-1).
  4298. .IP " 2." 4
  4299. Otherwise, set to the last line of the display.
  4300. .P
  4301. If
  4302. .IR line
  4303. and the
  4304. .BR '\(pl' 
  4305. character were specified, set to the first line of the display.
  4306. .P
  4307. Otherwise, if
  4308. .IR line
  4309. was specified, set to
  4310. .IR line .
  4311. .P
  4312. Otherwise, unchanged.
  4313. .P
  4314. .IR "Current column" :
  4315. Set to non-\c
  4316. <blank>.
  4317. .SS "Exit"
  4318. .IP "\fISynopsis\fR:" 10
  4319. .sp -1v
  4320. .RS 10 
  4321. .sp
  4322. .RS 4
  4323. .nf
  4325. ZZ
  4326. .fi
  4327. .P
  4328. .RE
  4329. .RE
  4330. .P
  4331. This command shall be equivalent to the
  4332. .IR ex
  4333. .BR xit
  4334. command with no addresses, trailing
  4335. .BR ! ,
  4336. or filename (see the
  4337. .IR ex
  4338. .BR xit
  4339. command).
  4340. .SS "Input Mode Commands in vi"
  4341. .P
  4342. In text input mode, the current line shall consist of zero or more of
  4343. the following categories, plus the terminating
  4344. <newline>:
  4345. .IP " 1." 4
  4346. Characters preceding the text input entry point
  4347. .RS 4 
  4348. .P
  4349. Characters in this category shall not be modified during text input
  4350. mode.
  4351. .RE
  4352. .IP " 2." 4
  4353. .BR autoindent
  4354. characters
  4355. .RS 4 
  4356. .P
  4357. .BR autoindent
  4358. characters shall be automatically inserted into each line that is
  4359. created in text input mode, either as a result of entering a
  4360. <newline>
  4361. or
  4362. <carriage-return>
  4363. while in text input mode, or as an effect of the command itself; for
  4364. example,
  4365. .BR O
  4366. or
  4367. .BR o
  4368. (see the
  4369. .IR ex
  4370. .BR autoindent
  4371. command), as if entered by the user.
  4372. .P
  4373. It shall be possible to erase
  4374. .BR autoindent
  4375. characters with the
  4376. <control>\(hyD
  4377. command; it is unspecified whether they can be erased by
  4378. <control>\(hyH,
  4379. <control>\(hyU,
  4380. and
  4381. <control>\(hyW
  4382. characters. Erasing any
  4383. .BR autoindent
  4384. character turns the glyph into erase-columns and deletes the character
  4385. from the edit buffer, but does not change its representation on the
  4386. screen.
  4387. .RE
  4388. .IP " 3." 4
  4389. Text input characters
  4390. .RS 4 
  4391. .P
  4392. Text input characters are the characters entered by the user. Erasing
  4393. any text input character turns the glyph into erase-columns and deletes
  4394. the character from the edit buffer, but does not change its
  4395. representation on the screen.
  4396. .P
  4397. Each text input character entered by the user (that does not have a
  4398. special meaning) shall be treated as follows:
  4399. .IP " a." 4
  4400. The text input character shall be appended to the last character in the
  4401. edit buffer from the first, second, or third categories.
  4402. .IP " b." 4
  4403. If there are no erase-columns on the screen, the text input command was
  4404. the
  4405. .BR R
  4406. command, and characters in the fifth category from the original line
  4407. follow the cursor, the next such character shall be deleted from the
  4408. edit buffer. If the
  4409. .BR slowopen
  4410. edit option is not set, the corresponding glyph on the screen shall
  4411. become erase-columns.
  4412. .IP " c." 4
  4413. If there are erase-columns on the screen, as many columns as they
  4414. occupy, or as are necessary, shall be overwritten to display the text
  4415. input character. (If only part of a multi-column glyph is overwritten,
  4416. the remainder shall be left on the screen, and continue to be treated
  4417. as erase-columns; it is unspecified whether the remainder of the glyph
  4418. is modified in any way.)
  4419. .IP " d." 4
  4420. If additional display line columns are needed to display the text input
  4421. character:
  4422. .RS 4 
  4423. .IP " i." 5
  4424. If the
  4425. .BR slowopen
  4426. edit option is set, the text input characters shall be displayed on
  4427. subsequent display line columns, overwriting any characters displayed
  4428. in those columns.
  4429. .IP ii. 5
  4430. Otherwise, any characters currently displayed on or after the column on
  4431. the display line where the text input character is to be displayed
  4432. shall be pushed ahead the number of display line columns necessary to
  4433. display the rest of the text input character.
  4434. .RE
  4435. .RE
  4436. .IP " 4." 4
  4437. Erase-columns
  4438. .RS 4 
  4439. .P
  4440. Erase-columns are not logically part of the edit buffer, appearing only
  4441. on the screen, and may be overwritten on the screen by subsequent text
  4442. input characters. When text input mode ends, all erase-columns shall no
  4443. longer appear on the screen.
  4444. .P
  4445. Erase-columns are initially the region of text specified by the
  4446. .BR c
  4447. command (see
  4448. .IR "Change");
  4449. however, erasing
  4450. .BR autoindent
  4451. or text input characters causes the glyphs of the erased characters to
  4452. be treated as erase-columns.
  4453. .RE
  4454. .IP " 5." 4
  4455. Characters following the text region for the
  4456. .BR c
  4457. command, or the text input entry point for all other commands
  4458. .RS 4 
  4459. .P
  4460. Characters in this category shall not be modified during text input
  4461. mode, except as specified in category 3.b. for the
  4462. .BR R
  4463. text input command, or as
  4464. <blank>
  4465. characters deleted when a
  4466. <newline>
  4467. or
  4468. <carriage-return>
  4469. is entered.
  4470. .RE
  4471. .P
  4472. It is unspecified whether it is an error to attempt to erase past the
  4473. beginning of a line that was created by the entry of a
  4474. <newline>
  4475. or
  4476. <carriage-return>
  4477. during text input mode. If it is not an error, the editor shall behave
  4478. as if the erasing character was entered immediately after the last text
  4479. input character entered on the previous line, and all of the non-\c
  4480. <newline>
  4481. characters on the current line shall be treated as erase-columns.
  4482. .P
  4483. When text input mode is entered, or after a text input mode character
  4484. is entered (except as specified for the special characters below), the
  4485. cursor shall be positioned as follows:
  4486. .IP " 1." 4
  4487. On the first column that displays any part of the first erase-column,
  4488. if one exists
  4489. .IP " 2." 4
  4490. Otherwise, if the
  4491. .BR slowopen
  4492. edit option is set, on the first display line column after the last
  4493. character in the first, second, or third categories, if one exists
  4494. .IP " 3." 4
  4495. Otherwise, the first column that displays any part of the first
  4496. character in the fifth category, if one exists
  4497. .IP " 4." 4
  4498. Otherwise, the display line column after the last character in the
  4499. first, second, or third categories, if one exists
  4500. .IP " 5." 4
  4501. Otherwise, on column position 1
  4502. .P
  4503. The characters that are updated on the screen during text input mode
  4504. are unspecified, other than that the last text input character shall
  4505. always be updated, and, if the
  4506. .BR slowopen
  4507. edit option is not set, the current cursor character shall always be
  4508. updated.
  4509. .P
  4510. The following specifications are for command characters entered during
  4511. text input mode.
  4512. .SS "NUL"
  4513. .IP "\fISynopsis\fR:" 10
  4514. .sp -1v
  4515. .RS 10 
  4516. .sp
  4517. .RS 4
  4518. .nf
  4520. NUL
  4521. .fi
  4522. .P
  4523. .RE
  4524. .RE
  4525. .P
  4526. If the first character of the text input is a NUL, the most recently
  4527. input text shall be input as if entered by the user, and then text
  4528. input mode shall be exited. The text shall be input literally; that is,
  4529. characters are neither macro or abbreviation expanded, nor are any
  4530. characters interpreted in any special manner. It is unspecified whether
  4531. implementations shall support more than 256 bytes of remembered input
  4532. text.
  4533. .SS "<control>-D"
  4534. .IP "\fISynopsis\fR:" 10
  4535. .sp -1v
  4536. .RS 10 
  4537. .sp
  4538. .RS 4
  4539. .nf
  4541. <control>-D
  4542. .fi
  4543. .P
  4544. .RE
  4545. .RE
  4546. .P
  4547. The
  4548. <control>\(hyD
  4549. character shall have no special meaning when in text input
  4550. mode for a line-oriented command (see
  4551. .IR "Command Descriptions in vi").
  4552. .P
  4553. This command need not be supported on block-mode terminals.
  4554. .P
  4555. If the cursor does not follow an
  4556. .BR autoindent
  4557. character, or an
  4558. .BR autoindent
  4559. character and a
  4560. .BR '0' 
  4561. or
  4562. .BR '\(ha' 
  4563. character:
  4564. .IP " 1." 4
  4565. If the cursor is in column position 1, the
  4566. <control>\(hyD
  4567. character shall be discarded and no further action taken.
  4568. .IP " 2." 4
  4569. Otherwise, the
  4570. <control>\(hyD
  4571. character shall have no special meaning.
  4572. .P
  4573. If the last input character was a
  4574. .BR '0' ,
  4575. the cursor shall be moved to column position 1.
  4576. .P
  4577. Otherwise, if the last input character was a
  4578. .BR '\(ha' ,
  4579. the cursor shall be moved to column position 1. In addition, the
  4580. .BR autoindent
  4581. level for the next input line shall be derived from the same line from
  4582. which the
  4583. .BR autoindent
  4584. level for the current input line was derived.
  4585. .P
  4586. Otherwise, the cursor shall be moved back to the column after the
  4587. previous shiftwidth (see the
  4588. .IR ex
  4589. .BR shiftwidth
  4590. command) boundary.
  4591. .P
  4592. All of the glyphs on columns between the starting cursor position and
  4593. (inclusively) the ending cursor position shall become erase-columns as
  4594. described in
  4595. .IR "Input Mode Commands in vi".
  4596. .P
  4597. .IR "Current line" :
  4598. Unchanged.
  4599. .P
  4600. .IR "Current column" :
  4601. Set to 1 if the
  4602. <control>\(hyD
  4603. was preceded by a
  4604. .BR '\(ha' 
  4605. or
  4606. .BR '0' ;
  4607. otherwise, set to (column \-1) \-((column \-2) %
  4608. .BR shiftwidth ).
  4609. .SS "<control>-H"
  4610. .IP "\fISynopsis\fR:" 10
  4611. .sp -1v
  4612. .RS 10 
  4613. .sp
  4614. .RS 4
  4615. .nf
  4617. <control>-H
  4618. .fi
  4619. .P
  4620. .RE
  4621. .RE
  4622. .P
  4623. If in text input mode for a line-oriented command, and there are no
  4624. characters to erase, text input mode shall be terminated, no further
  4625. action shall be done for this command, and the current line and column
  4626. shall be unchanged.
  4627. .P
  4628. If there are characters other than
  4629. .BR autoindent
  4630. characters that have been input on the current line before the cursor,
  4631. the cursor shall move back one character.
  4632. .P
  4633. Otherwise, if there are
  4634. .BR autoindent
  4635. characters on the current line before the cursor, it is
  4636. implementation-defined whether the
  4637. <control>\(hyH
  4638. command is an error or if the cursor moves back one
  4639. .BR autoindent
  4640. character.
  4641. .P
  4642. Otherwise, if the cursor is in column position 1 and there are previous
  4643. lines that have been input, it is implementation-defined whether the
  4644. <control>\(hyH
  4645. command is an error or if it is equivalent to entering
  4646. <control>\(hyH
  4647. after the last input character on the previous input line.
  4648. .P
  4649. Otherwise, it shall be an error.
  4650. .P
  4651. All of the glyphs on columns between the starting cursor position and
  4652. (inclusively) the ending cursor position shall become erase-columns as
  4653. described in
  4654. .IR "Input Mode Commands in vi".
  4655. .P
  4656. The current erase character (see
  4657. .IR stty )
  4658. shall cause an equivalent action to the
  4659. <control>\(hyH
  4660. command, unless the previously inserted character was a
  4661. <backslash>,
  4662. in which case it shall be as if the literal current erase character had
  4663. been inserted instead of the
  4664. <backslash>.
  4665. .P
  4666. .IR "Current line" :
  4667. Unchanged, unless previously input lines are erased, in which case it
  4668. shall be set to line \-1.
  4669. .P
  4670. .IR "Current column" :
  4671. Set to the first column that displays any portion of the character
  4672. backed up over.
  4673. .SS "<newline>"
  4674. .IP "\fISynopsis\fR:" 10
  4675. .sp -1v
  4676. .RS 10 
  4677. .sp
  4678. .RS 4
  4679. .nf
  4681. <newline>
  4682. .br
  4683. <carriage-return>
  4684. .br
  4685. <control>-J
  4686. .br
  4687. <control>-M
  4688. .fi
  4689. .P
  4690. .RE
  4691. .RE
  4692. .P
  4693. If input was part of a line-oriented command, text input mode shall be
  4694. terminated and the command shall continue execution with the input
  4695. provided.
  4696. .P
  4697. Otherwise, terminate the current line. If there are no characters other
  4698. than
  4699. .BR autoindent
  4700. characters on the line, all characters on the line shall be discarded.
  4701. Otherwise, it is unspecified whether the
  4702. .BR autoindent
  4703. characters in the line are modified by entering these characters.
  4704. .P
  4705. Continue text input mode on a new line appended after the current line.
  4706. If the
  4707. .BR slowopen
  4708. edit option is set, the lines on the screen below the current line
  4709. shall not be pushed down, but the first of them shall be cleared and
  4710. shall appear to be overwritten. Otherwise, the lines of the screen
  4711. below the current line shall be pushed down.
  4712. .P
  4713. If the
  4714. .BR autoindent
  4715. edit option is set, an appropriate number of
  4716. .BR autoindent
  4717. characters shall be added as a prefix to the line as described by the
  4718. .IR ex
  4719. .BR autoindent
  4720. edit option.
  4721. .P
  4722. All columns after the cursor that are erase-columns (as described in
  4723. .IR "Input Mode Commands in vi")
  4724. shall be discarded.
  4725. .P
  4726. If the
  4727. .BR autoindent
  4728. edit option is set, all
  4729. <blank>
  4730. characters immediately following the cursor shall be discarded.
  4731. .P
  4732. All remaining characters after the cursor shall be transferred to the
  4733. new line, positioned after any
  4734. .BR autoindent
  4735. characters.
  4736. .P
  4737. .IR "Current line" :
  4738. Set to current line +1.
  4739. .P
  4740. .IR "Current column" :
  4741. Set to the first column that displays any portion of the first
  4742. character after the
  4743. .BR autoindent
  4744. characters on the new line, if any, or the first column position after
  4745. the last
  4746. .BR autoindent
  4747. character, if any, or column position 1.
  4748. .SS "<control>-T"
  4749. .IP "\fISynopsis\fR:" 10
  4750. .sp -1v
  4751. .RS 10 
  4752. .sp
  4753. .RS 4
  4754. .nf
  4756. <control>-T
  4757. .fi
  4758. .P
  4759. .RE
  4760. .RE
  4761. .P
  4762. The
  4763. <control>\(hyT
  4764. character shall have no special meaning when in text input mode for a
  4765. line-oriented command (see
  4766. .IR "Command Descriptions in vi").
  4767. .P
  4768. This command need not be supported on block-mode terminals.
  4769. .P
  4770. Behave as if the user entered the minimum number of
  4771. <blank>
  4772. characters necessary to move the cursor forward to the column position
  4773. after the next
  4774. .BR shiftwidth
  4775. (see the
  4776. .IR ex
  4777. .BR shiftwidth
  4778. command) boundary.
  4779. .P
  4780. .IR "Current line" :
  4781. Unchanged.
  4782. .P
  4783. .IR "Current column" :
  4784. Set to
  4785. .IR column
  4786. +
  4787. .BR shiftwidth
  4788. \- ((column \-1) %
  4789. .BR shiftwidth ).
  4790. .SS "<control>-U"
  4791. .IP "\fISynopsis\fR:" 10
  4792. .sp -1v
  4793. .RS 10 
  4794. .sp
  4795. .RS 4
  4796. .nf
  4798. <control>-U
  4799. .fi
  4800. .P
  4801. .RE
  4802. .RE
  4803. .P
  4804. If there are characters other than
  4805. .BR autoindent
  4806. characters that have been input on the current line before the cursor,
  4807. the cursor shall move to the first character input after the
  4808. .BR autoindent
  4809. characters.
  4810. .P
  4811. Otherwise, if there are
  4812. .BR autoindent
  4813. characters on the current line before the cursor, it is
  4814. implementation-defined whether the
  4815. <control>\(hyU
  4816. command is an error or if the cursor moves to the first column position
  4817. on the line.
  4818. .P
  4819. Otherwise, if the cursor is in column position 1 and there are previous
  4820. lines that have been input, it is implementation-defined whether the
  4821. <control>\(hyU
  4822. command is an error or if it is equivalent to entering
  4823. <control>\(hyU
  4824. after the last input character on the previous input line.
  4825. .P
  4826. Otherwise, it shall be an error.
  4827. .P
  4828. All of the glyphs on columns between the starting cursor position and
  4829. (inclusively) the ending cursor position shall become erase-columns as
  4830. described in
  4831. .IR "Input Mode Commands in vi".
  4832. .P
  4833. The current
  4834. .IR kill
  4835. character (see
  4836. .IR stty )
  4837. shall cause an equivalent action to the
  4838. <control>\(hyU
  4839. command, unless the previously inserted character was a
  4840. <backslash>,
  4841. in which case it shall be as if the literal current
  4842. .IR kill
  4843. character had been inserted instead of the
  4844. <backslash>.
  4845. .P
  4846. .IR "Current line" :
  4847. Unchanged, unless previously input lines are erased, in which case it
  4848. shall be set to line \-1.
  4849. .P
  4850. .IR "Current column" :
  4851. Set to the first column that displays any portion of the last character
  4852. backed up over.
  4853. .SS "<control>-V"
  4854. .IP "\fISynopsis\fR:" 10
  4855. .sp -1v
  4856. .RS 10 
  4857. .sp
  4858. .RS 4
  4859. .nf
  4861. <control>-V
  4862. .br
  4863. <control>-Q
  4864. .fi
  4865. .P
  4866. .RE
  4867. .RE
  4868. .P
  4869. Allow the entry of any subsequent character, other than
  4870. <control>\(hyJ
  4871. or the
  4872. <newline>,
  4873. as a literal character, removing any special meaning that it may have
  4874. to the editor in text input mode. If a
  4875. <control>\(hyV
  4876. or
  4877. <control>\(hyQ
  4878. is entered before a
  4879. <control>\(hyJ
  4880. or
  4881. <newline>,
  4882. the
  4883. <control>\(hyV
  4884. or
  4885. <control>\(hyQ
  4886. character shall be discarded, and the
  4887. <control>\(hyJ
  4888. or
  4889. <newline>
  4890. shall behave as described in the
  4891. <newline>
  4892. command character during input mode.
  4893. .P
  4894. For purposes of the display only, the editor shall behave as if a
  4895. .BR '\(ha' 
  4896. character was entered, and the cursor shall be positioned as if
  4897. overwriting the
  4898. .BR '\(ha' 
  4899. character. When a subsequent character is entered, the editor shall
  4900. behave as if that character was entered instead of the original
  4901. <control>\(hyV
  4902. or
  4903. <control>\(hyQ
  4904. character.
  4905. .P
  4906. .IR "Current line" :
  4907. Unchanged.
  4908. .P
  4909. .IR "Current column" :
  4910. Unchanged.
  4911. .SS "<control>-W"
  4912. .IP "\fISynopsis\fR:" 10
  4913. .sp -1v
  4914. .RS 10 
  4915. .sp
  4916. .RS 4
  4917. .nf
  4919. <control>-W
  4920. .fi
  4921. .P
  4922. .RE
  4923. .RE
  4924. .P
  4925. If there are characters other than
  4926. .BR autoindent
  4927. characters that have been input on the current line before the cursor,
  4928. the cursor shall move back over the last word preceding the cursor
  4929. (including any
  4930. <blank>
  4931. characters between the end of the last word and the current cursor); the
  4932. cursor shall not move to before the first character after the end of any
  4933. .BR autoindent
  4934. characters.
  4935. .P
  4936. Otherwise, if there are
  4937. .BR autoindent
  4938. characters on the current line before the cursor, it is
  4939. implementation-defined whether the
  4940. <control>\(hyW
  4941. command is an error or if the cursor moves to the first column position
  4942. on the line.
  4943. .P
  4944. Otherwise, if the cursor is in column position 1 and there are previous
  4945. lines that have been input, it is implementation-defined whether the
  4946. <control>\(hyW
  4947. command is an error or if it is equivalent to entering
  4948. <control>\(hyW
  4949. after the last input character on the previous input line.
  4950. .P
  4951. Otherwise, it shall be an error.
  4952. .P
  4953. All of the glyphs on columns between the starting cursor position and
  4954. (inclusively) the ending cursor position shall become erase-columns as
  4955. described in
  4956. .IR "Input Mode Commands in vi".
  4957. .P
  4958. .IR "Current line" :
  4959. Unchanged, unless previously input lines are erased, in which case it
  4960. shall be set to line \-1.
  4961. .P
  4962. .IR "Current column" :
  4963. Set to the first column that displays any portion of the last character
  4964. backed up over.
  4965. .SS "<ESC>"
  4966. .IP "\fISynopsis\fR:" 10
  4967. .sp -1v
  4968. .RS 10 
  4969. .sp
  4970. .RS 4
  4971. .nf
  4973. <ESC>
  4974. .fi
  4975. .P
  4976. .RE
  4977. .RE
  4978. .P
  4979. If input was part of a line-oriented command:
  4980. .IP " 1." 4
  4981. If
  4982. .IR interrupt
  4983. was entered, text input mode shall be terminated and the editor shall
  4984. return to command mode. The terminal shall be alerted.
  4985. .IP " 2." 4
  4986. If
  4987. <ESC>
  4988. was entered, text input mode shall be terminated and the command shall
  4989. continue execution with the input provided.
  4990. .P
  4991. Otherwise, terminate text input mode and return to command mode.
  4992. .P
  4993. Any
  4994. .BR autoindent
  4995. characters entered on newly created lines that have no other non-\c
  4996. <newline>
  4997. characters shall be deleted.
  4998. .P
  4999. Any leading
  5000. .BR autoindent
  5001. and
  5002. <blank>
  5003. characters on newly created lines shall be rewritten to be the minimum
  5004. number of
  5005. <blank>
  5006. characters possible.
  5007. .P
  5008. The screen shall be redisplayed as necessary to match the contents of
  5009. the edit buffer.
  5010. .P
  5011. .IR "Current line" :
  5012. Unchanged.
  5013. .br
  5014. .P
  5015. .IR "Current column" :
  5016. .IP " 1." 4
  5017. If there are text input characters on the current line, the column
  5018. shall be set to the last column where any portion of the last text
  5019. input character is displayed.
  5020. .IP " 2." 4
  5021. Otherwise, if a character is displayed in the current column,
  5022. unchanged.
  5023. .IP " 3." 4
  5024. Otherwise, set to column position 1.
  5025. .SH "EXIT STATUS"
  5026. The following exit values shall be returned:
  5027. .IP "\00" 6
  5028. Successful completion.
  5029. .IP >0 6
  5030. An error occurred.
  5031. .SH "CONSEQUENCES OF ERRORS"
  5032. When any error is encountered and the standard input is not a terminal
  5033. device file,
  5034. .IR vi
  5035. shall not write the file or return to command or text input mode, and
  5036. shall terminate with a non-zero exit status.
  5037. .P
  5038. Otherwise, when an unrecoverable error is encountered it shall be
  5039. equivalent to a SIGHUP asynchronous event.
  5040. .P
  5041. Otherwise, when an error is encountered, the editor shall behave as
  5042. specified in
  5043. .IR "Command Descriptions in vi".
  5044. .LP
  5045. .IR "The following sections are informative."
  5046. .SH "APPLICATION USAGE"
  5047. None.
  5048. .SH EXAMPLES
  5049. None.
  5050. .SH RATIONALE
  5051. See the RATIONALE for
  5052. .IR "\fIex\fR\^"
  5053. for more information on
  5054. .IR vi .
  5055. Major portions of the
  5056. .IR vi
  5057. utility specification point to
  5058. .IR ex
  5059. to avoid inadvertent divergence. While
  5060. .IR ex
  5061. and
  5062. .IR vi
  5063. have historically been implemented as a single utility, this is not
  5064. required by POSIX.1\(hy2008.
  5065. .P
  5066. It is recognized that portions of
  5067. .IR vi
  5068. would be difficult, if not impossible, to implement satisfactorily on a
  5069. block-mode terminal, or a terminal without any form of cursor
  5070. addressing, thus it is not a mandatory requirement that such features
  5071. should work on all terminals. It is the intention, however, that a
  5072. .IR vi
  5073. implementation should provide the full set of capabilities on all
  5074. terminals capable of supporting them.
  5075. .P
  5076. Historically,
  5077. .IR vi
  5078. exited immediately if the standard input was not a terminal. POSIX.1\(hy2008
  5079. permits, but does not require, this behavior. An end-of-file condition
  5080. is not equivalent to an end-of-file character. A common end-of-file
  5081. character,
  5082. <control>\(hyD,
  5083. is historically a
  5084. .IR vi
  5085. command.
  5086. .P
  5087. The text in the STDOUT section reflects the usage of the verb
  5088. .IR display
  5089. in this section; some implementations of
  5090. .IR vi
  5091. use standard output to write to the terminal, but POSIX.1\(hy2008 does not
  5092. require that to be the case.
  5093. .P
  5094. Historically, implementations reverted to open mode if the terminal was
  5095. incapable of supporting full visual mode. POSIX.1\(hy2008 requires this
  5096. behavior. Historically, the open mode of
  5097. .IR vi
  5098. behaved roughly equivalently to the visual mode, with the exception
  5099. that only a single line from the edit buffer (one ``buffer line'') was
  5100. kept current at any time. This line was normally displayed on the
  5101. next-to-last line of a terminal with cursor addressing (and the last
  5102. line performed its normal visual functions for line-oriented commands
  5103. and messages). In addition, some few commands behaved differently in
  5104. open mode than in visual mode. POSIX.1\(hy2008 requires conformance to historical
  5105. practice.
  5106. .P
  5107. Historically,
  5108. .IR ex
  5109. and
  5110. .IR vi
  5111. implementations have expected text to proceed in the usual
  5112. European/Latin order of left to right, top to bottom. There is no
  5113. requirement in POSIX.1\(hy2008 that this be the case. The specification was
  5114. deliberately written using words like ``before'', ``after'', ``first'',
  5115. and ``last'' in order to permit implementations to support the natural
  5116. text order of the language.
  5117. .P
  5118. Historically, lines past the end of the edit buffer were marked with
  5119. single
  5120. <tilde>
  5121. (\c
  5122. .BR '\(ti' )
  5123. characters; that is, if the one-based display was 20 lines in length,
  5124. and the last line of the file was on line one, then lines 2-20 would
  5125. contain only a single
  5126. .BR '\(ti' 
  5127. character.
  5128. .P
  5129. Historically, the
  5130. .IR vi
  5131. editor attempted to display only complete lines at the bottom of the
  5132. screen (it did display partial lines at the top of the screen). If a
  5133. line was too long to fit in its entirety at the bottom of the screen,
  5134. the screen lines where the line would have been displayed were
  5135. displayed as single
  5136. .BR '@' 
  5137. characters, instead of displaying part of the line. POSIX.1\(hy2008 permits, but
  5138. does not require, this behavior. Implementations are encouraged to
  5139. attempt always to display a complete line at the bottom of the screen
  5140. when doing scrolling or screen positioning by buffer lines.
  5141. .P
  5142. Historically, lines marked with
  5143. .BR '@' 
  5144. were also used to minimize output to dumb terminals over slow lines;
  5145. that is, changes local to the cursor were updated, but changes to lines
  5146. on the screen that were not close to the cursor were simply marked with
  5147. an
  5148. .BR '@' 
  5149. sign instead of being updated to match the current text. POSIX.1\(hy2008 permits,
  5150. but does not require this feature because it is used ever less
  5151. frequently as terminals become smarter and connections are faster.
  5152. .SS "Initialization in ex and vi"
  5153. .P
  5154. Historically,
  5155. .IR vi
  5156. always had a line in the edit buffer, even if the edit buffer was
  5157. ``empty''. For example:
  5158. .IP " 1." 4
  5159. The
  5160. .IR ex
  5161. command
  5162. .BR =
  5163. executed from visual mode wrote ``1'' when the buffer was empty.
  5164. .IP " 2." 4
  5165. Writes from visual mode of an empty edit buffer wrote files of a single
  5166. character (a
  5167. <newline>),
  5168. while writes from
  5169. .IR ex
  5170. mode of an empty edit buffer wrote empty files.
  5171. .IP " 3." 4
  5172. Put and read commands into an empty edit buffer left an empty line at
  5173. the top of the edit buffer.
  5174. .P
  5175. For consistency, POSIX.1\(hy2008 does not permit any of these behaviors.
  5176. .P
  5177. Historically,
  5178. .IR vi
  5179. did not always return the terminal to its original modes; for example,
  5180. ICRNL was modified if it was not originally set. POSIX.1\(hy2008 does not permit
  5181. this behavior.
  5182. .SS "Command Descriptions in vi"
  5183. .P
  5184. Motion commands are among the most complicated aspects of
  5185. .IR vi
  5186. to describe. With some exceptions, the text region and buffer type
  5187. effect of a motion command on a
  5188. .IR vi
  5189. command are described on a case-by-case basis. The descriptions of text
  5190. regions in POSIX.1\(hy2008 are not intended to imply direction; that is, an
  5191. inclusive region from line
  5192. .IR n
  5193. to line
  5194. .IR n +5
  5195. is identical to a region from line
  5196. .IR n +5
  5197. to line
  5198. .IR n .
  5199. This is of more than academic interest\(emmovements to marks can be in
  5200. either direction, and, if the
  5201. .BR wrapscan
  5202. option is set, so can movements to search points. Historically, lines
  5203. are always stored into buffers in text order; that is, from the start
  5204. of the edit buffer to the end. POSIX.1\(hy2008 requires conformance to historical
  5205. practice.
  5206. .P
  5207. Historically, command counts were applied to any associated motion, and
  5208. were multiplicative to any supplied motion count. For example,
  5209. .BR 2cw
  5210. is the same as
  5211. .BR c2w ,
  5212. and
  5213. .BR 2c3w
  5214. is the same as
  5215. .BR c6w .
  5216. POSIX.1\(hy2008 requires this behavior. Historically,
  5217. .IR vi
  5218. commands that used bigwords, words, paragraphs, and sentences as
  5219. objects treated groups of empty lines, or lines that contained only
  5220. <blank>
  5221. characters, inconsistently. Some commands treated them as a single entity,
  5222. while others treated each line separately. For example, the
  5223. .BR w ,
  5224. .BR W ,
  5225. and
  5226. .BR B
  5227. commands treated groups of empty lines as individual words; that is,
  5228. the command would move the cursor to each new empty line. The
  5229. .BR e
  5230. and
  5231. .BR E
  5232. commands treated groups of empty lines as a single word; that is, the
  5233. first use would move past the group of lines. The
  5234. .BR b
  5235. command would just beep at the user, or if done from the start of the
  5236. line as a motion command, fail in unexpected ways. If the lines
  5237. contained only (or ended with)
  5238. <blank>
  5239. characters, the
  5240. .BR w
  5241. and
  5242. .BR W
  5243. commands would just beep at the user, the
  5244. .BR E
  5245. and
  5246. .BR e
  5247. commands would treat the group as a single word, and the
  5248. .BR B
  5249. and
  5250. .BR b
  5251. commands would treat the lines as individual words. For consistency and
  5252. simplicity of specification, POSIX.1\(hy2008 requires that all
  5253. .IR vi
  5254. commands treat groups of empty or blank lines as a single entity, and
  5255. that movement through lines ending with
  5256. <blank>
  5257. characters be consistent with other movements.
  5258. .P
  5259. Historically,
  5260. .IR vi
  5261. documentation indicated that any number of double-quotes were skipped
  5262. after punctuation marks at sentence boundaries; however,
  5263. implementations only skipped single-quotes. POSIX.1\(hy2008 requires both to be
  5264. skipped.
  5265. .P
  5266. Historically, the first and last characters in the edit buffer were
  5267. word boundaries. This historical practice is required by POSIX.1\(hy2008.
  5268. .P
  5269. Historically,
  5270. .IR vi
  5271. attempted to update the minimum number of columns on the screen
  5272. possible, which could lead to misleading information being displayed.
  5273. POSIX.1\(hy2008 makes no requirements other than that the current character being
  5274. entered is displayed correctly, leaving all other decisions in this
  5275. area up to the implementation.
  5276. .P
  5277. Historically, lines were arbitrarily folded between columns of any
  5278. characters that required multiple column positions on the screen, with
  5279. the exception of tabs, which terminated at the right-hand margin. POSIX.1\(hy2008
  5280. permits the former and requires the latter. Implementations that do not
  5281. arbitrarily break lines between columns of characters that occupy
  5282. multiple column positions should not permit the cursor to rest on a
  5283. column that does not contain any part of a character.
  5284. .P
  5285. The historical
  5286. .IR vi
  5287. had a problem in that all movements were by buffer lines, not by
  5288. display or screen lines. This is often the right thing to do; for
  5289. example, single line movements, such as
  5290. .BR j
  5291. or
  5292. .BR k ,
  5293. should work on buffer lines. Commands like
  5294. .BR dj ,
  5295. or
  5296. .BR j. ,
  5297. where
  5298. .BR .
  5299. is a change command, only make sense for buffer lines. It is not,
  5300. however, the right thing to do for screen motion or scrolling commands
  5301. like
  5302. <control>\(hyD,
  5303. <control>\(hyF,
  5304. and
  5305. .BR H .
  5306. If the window is fairly small, using buffer lines in these cases can
  5307. result in completely random motion; for example,
  5308. .BR 1 \c
  5309. <control>\c
  5310. .BR \(hyD
  5311. can result in a completely changed screen, without any overlap. This is
  5312. clearly not what the user wanted. The problem is even worse in the case
  5313. of the
  5314. .BR H ,
  5315. .BR L ,
  5316. and
  5317. .BR M
  5318. commands\(emas they position the cursor at the first non-\c
  5319. <blank>
  5320. of the line, they may all refer to the same location in large lines,
  5321. and will result in no movement at all.
  5322. .P
  5323. In addition, if the line is larger than the screen, using buffer
  5324. lines can make it impossible to display parts of the line\(emthere are
  5325. not any commands that do not display the beginning of the line in
  5326. historical
  5327. .IR vi ,
  5328. and if both the beginning and end of the line cannot be on the screen
  5329. at the same time, the user suffers. Finally, the page and half-page
  5330. scrolling commands historically moved to the first non-\c
  5331. <blank>
  5332. in the new line. If the line is approximately the same size as the
  5333. screen, this is inadequate because the cursor before and after a
  5334. <control>\(hyD
  5335. command will refer to the same location on the screen.
  5336. .P
  5337. Implementations of
  5338. .IR ex
  5339. and
  5340. .IR vi
  5341. exist that do not have these problems because the relevant commands (\c
  5342. <control>\(hyB,
  5343. <control>\(hyD,
  5344. <control>\(hyF,
  5345. <control>\(hyU,
  5346. <control>\(hyY,
  5347. <control>\(hyE,
  5348. .BR H ,
  5349. .BR L ,
  5350. and
  5351. .BR M)
  5352. operate on display (screen) lines, not (edit) buffer lines.
  5353. .P
  5354. POSIX.1\(hy2008 does not permit this behavior by default because the standard
  5355. developers believed that users would find it too confusing. However,
  5356. historical practice has been relaxed. For example,
  5357. .IR ex
  5358. and
  5359. .IR vi
  5360. historically attempted, albeit sometimes unsuccessfully, to never put
  5361. part of a line on the last lines of a screen; for example, if a line
  5362. would not fit in its entirety, no part of the line was displayed, and
  5363. the screen lines corresponding to the line contained single
  5364. .BR '@' 
  5365. characters. This behavior is permitted, but not required by POSIX.1\(hy2008, so
  5366. that it is possible for implementations to support long lines in small
  5367. screens more reasonably without changing the commands to be oriented to
  5368. the display (instead of oriented to the buffer). POSIX.1\(hy2008 also permits
  5369. implementations to refuse to edit any edit buffer containing a line
  5370. that will not fit on the screen in its entirety.
  5371. .P
  5372. The display area (for example, the value of the
  5373. .BR window
  5374. edit option) has historically been ``grown'', or expanded, to display
  5375. new text when local movements are done in displays where the number of
  5376. lines displayed is less than the maximum possible. Expansion has
  5377. historically been the first choice, when the target line is less than
  5378. the maximum possible expansion value away. Scrolling has historically
  5379. been the next choice, done when the target line is less than half a
  5380. display away, and otherwise, the screen was redrawn. There were
  5381. exceptions, however, in that
  5382. .IR ex
  5383. commands generally always caused the screen to be redrawn. POSIX.1\(hy2008 does
  5384. not specify a standard behavior because there may be external issues,
  5385. such as connection speed, the number of characters necessary to redraw
  5386. as opposed to scroll, or terminal capabilities that implementations
  5387. will have to accommodate.
  5388. .P
  5389. The current line in POSIX.1\(hy2008 maps one-to-one to a buffer line in the
  5390. file. The current column does not. There are two different column
  5391. values that are described by POSIX.1\(hy2008. The first is the current column
  5392. value as set by many of the
  5393. .IR vi
  5394. commands. This value is remembered for the lifetime of the editor. The
  5395. second column value is the actual position on the screen where the
  5396. cursor rests. The two are not always the same. For example, when the
  5397. cursor is backed by a multi-column character, the actual cursor
  5398. position on the screen has historically been the last column of the
  5399. character in command mode, and the first column of the character in
  5400. input mode.
  5401. .P
  5402. Commands that set the current line, but that do not set the current
  5403. cursor value (for example,
  5404. .BR j
  5405. and
  5406. .BR k )
  5407. attempt to get as close as possible to the remembered column position,
  5408. so that the cursor tends to restrict itself to a vertical column as the
  5409. user moves around in the edit buffer. POSIX.1\(hy2008 requires conformance to
  5410. historical practice, requiring that the display location of the cursor
  5411. on the display line be adjusted from the current column value as
  5412. necessary to support this historical behavior.
  5413. .P
  5414. Historically, only a single line (and for some terminals, a single line
  5415. minus 1 column) of characters could be entered by the user for the
  5416. line-oriented commands; that is,
  5417. .BR : ,
  5418. .BR ! ,
  5419. .BR / ,
  5420. or
  5421. .BR ? .
  5422. POSIX.1\(hy2008 permits, but does not require, this limitation.
  5423. .P
  5424. Historically, ``soft'' errors in
  5425. .IR vi
  5426. caused the terminal to be alerted, but no error message was displayed.
  5427. As a general rule, no error message was displayed for errors in command
  5428. execution in
  5429. .IR vi ,
  5430. when the error resulted from the user attempting an invalid or
  5431. impossible action, or when a searched-for object was not found.
  5432. Examples of soft errors included
  5433. .BR h
  5434. at the left margin,
  5435. <control>\(hyB
  5436. or
  5437. .BR [[
  5438. at the beginning of the file,
  5439. .BR 2G
  5440. at the end of the file, and so on. In addition, errors such as
  5441. .BR % ,
  5442. .BR ]] ,
  5443. .BR } ,
  5444. .BR ) ,
  5445. .BR N ,
  5446. .BR n ,
  5447. .BR f ,
  5448. .BR F ,
  5449. .BR t ,
  5450. and
  5451. .BR T
  5452. failing to find the searched-for object were soft as well. Less
  5453. consistently,
  5454. .BR /
  5455. and
  5456. .BR ?
  5457. displayed an error message if the pattern was not found,
  5458. .BR / ,
  5459. .BR ? ,
  5460. .BR N ,
  5461. and
  5462. .BR n
  5463. displayed an error message if no previous regular expression had been
  5464. specified, and
  5465. .BR ;
  5466. did not display an error message if no previous
  5467. .BR f ,
  5468. .BR F ,
  5469. .BR t ,
  5470. or
  5471. .BR T
  5472. command had occurred. Also, behavior in this area might reasonably be
  5473. based on a runtime evaluation of the speed of a network connection.
  5474. Finally, some implementations have provided error messages for soft
  5475. errors in order to assist naive users, based on the value of a verbose
  5476. edit option. POSIX.1\(hy2008 does not list specific errors for which an error
  5477. message shall be displayed. Implementations should conform to
  5478. historical practice in the absence of any strong reason to diverge.
  5479. .SS "Page Backwards"
  5480. .P
  5481. The
  5482. <control>\(hyB
  5483. and
  5484. <control>\(hyF
  5485. commands historically considered it an error to attempt to page past
  5486. the beginning or end of the file, whereas the
  5487. <control>\(hyD
  5488. and
  5489. <control>\(hyU
  5490. commands simply moved to the beginning or end of the file. For
  5491. consistency, POSIX.1\(hy2008 requires the latter behavior for all four commands.
  5492. All four commands still consider it an error if the current line is at
  5493. the beginning (\c
  5494. <control>\(hyB,
  5495. <control>\(hyU)
  5496. or end (\c
  5497. <control>\(hyF,
  5498. <control>\(hyD)
  5499. of the file. Historically, the
  5500. <control>\(hyB
  5501. and
  5502. <control>\(hyF
  5503. commands skip two lines in order to include overlapping lines when a
  5504. single command is entered. This makes less sense in the presence of a
  5505. .IR count ,
  5506. as there will be, by definition, no overlapping lines. The actual
  5507. calculation used by historical implementations of the
  5508. .IR vi
  5509. editor for
  5510. <control>\(hyB
  5511. was:
  5512. .sp
  5513. .RS 4
  5514. .nf
  5516. ((current first line) - count x (window edit option)) +2
  5517. .fi
  5518. .P
  5519. .RE
  5520. .P
  5521. and for
  5522. <control>\(hyF
  5523. was:
  5524. .sp
  5525. .RS 4
  5526. .nf
  5528. ((current first line) + count x (window edit option)) -2
  5529. .fi
  5530. .P
  5531. .RE
  5532. .P
  5533. This calculation does not work well when intermixing commands with and
  5534. without counts; for example,
  5535. .BR 3\c
  5536. <control>\(hyF
  5537. is not equivalent to entering the
  5538. <control>\(hyF
  5539. command three times, and is not reversible by entering the
  5540. <control>\(hyB
  5541. command three times. For consistency with other
  5542. .IR vi
  5543. commands that take counts, POSIX.1\(hy2008 requires a different calculation.
  5544. .SS "Scroll Forward"
  5545. .P
  5546. The 4BSD and System V implementations of
  5547. .IR vi
  5548. differed on the initial value used by the
  5549. .BR scroll
  5550. command. 4BSD used:
  5551. .sp
  5552. .RS 4
  5553. .nf
  5555. ((window edit option) +1) /2
  5556. .fi
  5557. .P
  5558. .RE
  5559. .P
  5560. while System V used the value of the
  5561. .BR scroll
  5562. edit option. The System V version is specified by POSIX.1\(hy2008 because the
  5563. standard developers believed that it was more intuitive and permitted
  5564. the user a method of setting the scroll value initially without also
  5565. setting the number of lines that are displayed.
  5566. .SS "Scroll Forward by Line"
  5567. .P
  5568. Historically, the
  5569. <control>\(hyE
  5570. and
  5571. <control>\(hyY
  5572. commands considered it an error if the last and first lines,
  5573. respectively, were already on the screen. POSIX.1\(hy2008 requires conformance to
  5574. historical practice. Historically, the
  5575. <control>\(hyE
  5576. and
  5577. <control>\(hyY
  5578. commands had no effect in open mode. For simplicity and consistency of
  5579. specification, POSIX.1\(hy2008 requires that they behave as usual, albeit with a
  5580. single line screen.
  5581. .SS "Clear and Redisplay"
  5582. .P
  5583. The historical
  5584. <control>\(hyL
  5585. command refreshed the screen exactly as it was supposed to be currently
  5586. displayed, replacing any
  5587. .BR '@' 
  5588. characters for lines that had been deleted but not updated on the
  5589. screen with refreshed
  5590. .BR '@' 
  5591. characters. The intent of the
  5592. <control>\(hyL
  5593. command is to refresh when the screen has been accidentally
  5594. overwritten; for example, by a
  5595. .BR write
  5596. command from another user, or modem noise.
  5597. .SS "Redraw Screen"
  5598. .P
  5599. The historical
  5600. <control>\(hyR
  5601. command redisplayed only when necessary to update lines that had been
  5602. deleted but not updated on the screen and that were flagged with
  5603. .BR '@' 
  5604. characters. There is no requirement that the screen be in any way
  5605. refreshed if no lines of this form are currently displayed. POSIX.1\(hy2008
  5606. permits implementations to extend this command to refresh lines on the
  5607. screen flagged with
  5608. .BR '@' 
  5609. characters because they are too long to be displayed in the current
  5610. framework; however, the current line and column need not be modified.
  5611. .SS "Search for tagstring"
  5612. .P
  5613. Historically, the first non-\c
  5614. <blank>
  5615. at or after the cursor was the first character, and all subsequent
  5616. characters that were word characters, up to the end of the line, were
  5617. included. For example, with the cursor on the leading
  5618. <space>
  5619. or on the
  5620. .BR '#' 
  5621. character in the text
  5622. .BR \(dq#bar@\(dq ,
  5623. the tag was
  5624. .BR \(dq#bar\(dq .
  5625. On the character
  5626. .BR 'b' 
  5627. it was
  5628. .BR \(dqbar\(dq ,
  5629. and on the
  5630. .BR 'a' 
  5631. it was
  5632. .BR \(dqar\(dq .
  5633. POSIX.1\(hy2008 requires this behavior.
  5634. .SS "Replace Text with Results from Shell Command"
  5635. .P
  5636. Historically, the
  5637. .BR < ,
  5638. .BR > ,
  5639. and
  5640. .BR !
  5641. commands considered most cursor motions other than line-oriented
  5642. motions an error; for example, the command
  5643. .BR ">/foo<CR>"
  5644. succeeded, while the command
  5645. .BR ">l"
  5646. failed, even though the text region described by the two commands might
  5647. be identical. For consistency, all three commands only consider entire
  5648. lines and not partial lines, and the region is defined as any line that
  5649. contains a character that was specified by the motion.
  5650. .SS "Move to Matching Character"
  5651. .P
  5652. Other matching characters have been left implementation-defined in
  5653. order to allow extensions such as matching
  5654. .BR '<' 
  5655. and
  5656. .BR '>' 
  5657. for searching HTML, or
  5658. .BR #ifdef ,
  5659. .BR #else ,
  5660. and
  5661. .BR #endif
  5662. for searching C source.
  5663. .SS "Repeat Substitution"
  5664. .P
  5665. POSIX.1\(hy2008 requires that any
  5666. .BR c
  5667. and
  5668. .BR g
  5669. flags specified to the previous substitute command be ignored; however,
  5670. the
  5671. .BR r
  5672. flag may still apply, if supported by the implementation.
  5673. .SS "Return to Previous (Context or Section)"
  5674. .P
  5675. The
  5676. .BR [[ ,
  5677. .BR ]] ,
  5678. .BR ( ,
  5679. .BR ) ,
  5680. .BR { ,
  5681. and
  5682. .BR }
  5683. commands are all affected by ``section boundaries'', but in some
  5684. historical implementations not all of the commands recognize the same
  5685. section boundaries. This is a bug, not a feature, and a unique
  5686. section-boundary algorithm was not described for each command. One
  5687. special case that is preserved is that the sentence command moves to
  5688. the end of the last line of the edit buffer while the other commands go
  5689. to the beginning, in order to preserve the traditional character cut
  5690. semantics of the sentence command. Historically,
  5691. .IR vi
  5692. section boundaries at the beginning and end of the edit buffer were the
  5693. first non-\c
  5694. <blank>
  5695. on the first and last lines of the edit buffer if one exists;
  5696. otherwise, the last character of the first and last lines of the edit
  5697. buffer if one exists. To increase consistency with other section
  5698. locations, this has been simplified by POSIX.1\(hy2008 to the first character of
  5699. the first and last lines of the edit buffer, or the first and the last
  5700. lines of the edit buffer if they are empty.
  5701. .P
  5702. Sentence boundaries were problematic in the historical
  5703. .IR vi .
  5704. They were not only the boundaries as defined for the section and
  5705. paragraph commands, but they were the first non-\c
  5706. <blank>
  5707. that occurred after those boundaries, as well. Historically, the
  5708. .IR vi
  5709. section commands were documented as taking an optional window size as a
  5710. .IR count
  5711. preceding the command. This was not implemented in historical versions,
  5712. so POSIX.1\(hy2008 requires that the
  5713. .IR count
  5714. repeat the command, for consistency with other
  5715. .IR vi
  5716. commands.
  5717. .SS "Repeat"
  5718. .P
  5719. Historically, mapped commands other than text input commands could not
  5720. be repeated using the
  5721. .BR period
  5722. command. POSIX.1\(hy2008 requires conformance to historical practice.
  5723. .P
  5724. The restrictions on the interpretation of special characters (for
  5725. example,
  5726. <control>\(hyH)
  5727. in the repetition of text input mode commands is intended to match
  5728. historical practice. For example, given the input sequence:
  5729. .sp
  5730. .RS 4
  5731. .nf
  5733. iab<control>-H<control>-H<control>-Hdef<escape>
  5734. .fi
  5735. .P
  5736. .RE
  5737. .P
  5738. the user should be informed of an error when the sequence is first
  5739. entered, but not during a command repetition. The character
  5740. <control>\(hyT
  5741. is specifically exempted from this restriction. Historical
  5742. implementations of
  5743. .IR vi
  5744. ignored
  5745. <control>\(hyT
  5746. characters that were input in the original command during command
  5747. repetition. POSIX.1\(hy2008 prohibits this behavior.
  5748. .SS "Find Regular Expression"
  5749. .P
  5750. Historically, commands did not affect the line searched to or from if
  5751. the motion command was a search (\c
  5752. .BR / ,
  5753. .BR ? ,
  5754. .BR N ,
  5755. .BR n )
  5756. and the final position was the start/end of the line. There were some
  5757. special cases and
  5758. .IR vi
  5759. was not consistent. POSIX.1\(hy2008 does not permit this behavior, for
  5760. consistency. Historical implementations permitted but were unable to
  5761. handle searches as motion commands that wrapped (that is, due to the
  5762. edit option
  5763. .BR wrapscan )
  5764. to the original location. POSIX.1\(hy2008 requires that this behavior be treated
  5765. as an error.
  5766. .P
  5767. Historically, the syntax
  5768. .BR \(dq/RE/0\(dq 
  5769. was used to force the command to cut text in line mode. POSIX.1\(hy2008 requires
  5770. conformance to historical practice.
  5771. .P
  5772. Historically, in open mode, a
  5773. .BR z
  5774. specified to a search command redisplayed the current line instead of
  5775. displaying the current screen with the current line highlighted. For
  5776. consistency and simplicity of specification, POSIX.1\(hy2008 does not permit this
  5777. behavior.
  5778. .P
  5779. Historically, trailing
  5780. .BR z
  5781. commands were permitted and ignored if entered as part of a search used
  5782. as a motion command. For consistency and simplicity of specification,
  5783. POSIX.1\(hy2008 does not permit this behavior.
  5784. .SS "Execute an ex Command"
  5785. .P
  5786. Historically,
  5787. .IR vi
  5788. implementations restricted the commands that could be entered on the
  5789. colon command line (for example,
  5790. .BR append
  5791. and
  5792. .BR change ),
  5793. and some other commands were known to cause them to fail
  5794. catastrophically. For consistency, POSIX.1\(hy2008 does not permit these
  5795. restrictions. When executing an
  5796. .IR ex
  5797. command by entering
  5798. .BR : ,
  5799. it is not possible to enter a
  5800. <newline>
  5801. as part of the command because it is considered the end of the command.
  5802. A different approach is to enter
  5803. .IR ex
  5804. command mode by using the
  5805. .IR vi
  5806. .BR Q
  5807. command (and later resuming visual mode with the
  5808. .IR ex
  5809. .BR vi
  5810. command). In
  5811. .IR ex
  5812. command mode, the single-line limitation does not exist. So, for
  5813. example, the following is valid:
  5814. .sp
  5815. .RS 4
  5816. .nf
  5818. Q
  5819. s/break here/break\e
  5820. here/
  5821. vi
  5822. .fi
  5823. .P
  5824. .RE
  5825. .P
  5826. POSIX.1\(hy2008 requires that, if the
  5827. .IR ex
  5828. command overwrites any part of the screen that would be erased by a
  5829. refresh,
  5830. .IR vi
  5831. pauses for a character from the user. Historically, this character
  5832. could be any character; for example, a character input by the user
  5833. before the message appeared, or even a mapped character. This is
  5834. probably a bug, but implementations that have tried to be more rigorous
  5835. by requiring that the user enter a specific character, or that the user
  5836. enter a character after the message was displayed, have been forced by
  5837. user indignation back into historical behavior. POSIX.1\(hy2008 requires
  5838. conformance to historical practice.
  5839. .SS "Shift Left (Right)"
  5840. .P
  5841. Refer to the Rationale for the
  5842. .BR !
  5843. and
  5844. .BR /
  5845. commands. Historically, the
  5846. .BR <
  5847. and
  5848. .BR >
  5849. commands sometimes moved the cursor to the first non-\c
  5850. <blank>
  5851. (for example if the command was repeated or with
  5852. .BR _
  5853. as the motion command), and sometimes left it unchanged. POSIX.1\(hy2008 does not
  5854. permit this inconsistency, requiring instead that the cursor always
  5855. move to the first non-\c
  5856. <blank>.
  5857. Historically, the
  5858. .BR <
  5859. and
  5860. .BR >
  5861. commands did not support buffer arguments, although some
  5862. implementations allow the specification of an optional buffer. This
  5863. behavior is neither required nor disallowed by POSIX.1\(hy2008.
  5864. .SS "Execute"
  5865. .P
  5866. Historically, buffers could execute other buffers, and loops, infinite
  5867. and otherwise, were possible. POSIX.1\(hy2008 requires conformance to historical
  5868. practice. The *\c
  5869. .IR buffer
  5870. syntax of
  5871. .IR ex
  5872. is not required in
  5873. .IR vi ,
  5874. because it is not historical practice and has been used in some
  5875. .IR vi
  5876. implementations to support additional scripting languages.
  5877. .SS "Reverse Case"
  5878. .P
  5879. Historically, the
  5880. .BR ~
  5881. command ignored any associated
  5882. .IR count ,
  5883. and acted only on the characters in the current line. For consistency
  5884. with other
  5885. .IR vi
  5886. commands, POSIX.1\(hy2008 requires that an associated
  5887. .IR count
  5888. act on the next
  5889. .IR count
  5890. characters, and that the command move to subsequent lines if warranted
  5891. by
  5892. .IR count ,
  5893. to make it possible to modify large pieces of text in a reasonably
  5894. efficient manner. There exist
  5895. .IR vi
  5896. implementations that optionally require an associated motion command
  5897. for the
  5898. .BR ~
  5899. command. Implementations supporting this functionality are encouraged
  5900. to base it on the
  5901. .BR tildedop
  5902. edit option and handle the text regions and cursor positioning
  5903. identically to the
  5904. .BR yank
  5905. command.
  5906. .SS "Append"
  5907. .P
  5908. Historically,
  5909. .IR count s
  5910. specified to the
  5911. .BR A ,
  5912. .BR a ,
  5913. .BR I ,
  5914. and
  5915. .BR i
  5916. commands repeated the input of the first line
  5917. .IR count
  5918. times, and did not repeat the subsequent lines of the input text. POSIX.1\(hy2008
  5919. requires that the entire text input be repeated
  5920. .IR count
  5921. times.
  5922. .SS "Move Backward to Preceding Word"
  5923. .P
  5924. Historically,
  5925. .IR vi
  5926. became confused if word commands were used as motion commands in empty
  5927. files. POSIX.1\(hy2008 requires that this be an error. Historical implementations
  5928. of
  5929. .IR vi
  5930. had a large number of bugs in the word movement commands, and they
  5931. varied greatly in behavior in the presence of empty lines, ``words''
  5932. made up of a single character, and lines containing only
  5933. <blank>
  5934. characters. For consistency and simplicity of specification, POSIX.1\(hy2008 does
  5935. not permit this behavior.
  5936. .SS "Change to End-of-Line"
  5937. .P
  5938. Some historical implementations of the
  5939. .BR C
  5940. command did not behave as described by POSIX.1\(hy2008 when the
  5941. .BR $
  5942. key was remapped because they were implemented by pushing the
  5943. .BR $
  5944. key onto the input queue and reprocessing it. POSIX.1\(hy2008 does not permit
  5945. this behavior. Historically, the
  5946. .BR C ,
  5947. .BR S ,
  5948. and
  5949. .BR s
  5950. commands did not copy replaced text into the numeric buffers. For
  5951. consistency and simplicity of specification, POSIX.1\(hy2008 requires that they
  5952. behave like their respective
  5953. .BR c
  5954. commands in all respects.
  5955. .SS "Delete"
  5956. .P
  5957. Historically, lines in open mode that were deleted were scrolled up,
  5958. and an
  5959. .BR @
  5960. glyph written over the beginning of the line. In the case of terminals
  5961. that are incapable of the necessary cursor motions, the editor erased
  5962. the deleted line from the screen. POSIX.1\(hy2008 requires conformance to
  5963. historical practice; that is, if the terminal cannot display the
  5964. .BR '@' 
  5965. character, the line cannot remain on the screen.
  5966. .SS "Delete to End-of-Line"
  5967. .P
  5968. Some historical implementations of the
  5969. .BR D
  5970. command did not behave as described by POSIX.1\(hy2008 when the
  5971. .BR $
  5972. key was remapped because they were implemented by pushing the
  5973. .BR $
  5974. key onto the input queue and reprocessing it. POSIX.1\(hy2008 does not permit
  5975. this behavior.
  5976. .SS "Join"
  5977. .P
  5978. An historical oddity of
  5979. .IR vi
  5980. is that the commands
  5981. .BR J ,
  5982. .BR 1J ,
  5983. and
  5984. .BR 2J
  5985. are all equivalent. POSIX.1\(hy2008 requires conformance to historical practice.
  5986. The
  5987. .IR vi
  5988. .BR J
  5989. command is specified in terms of the
  5990. .IR ex
  5991. .BR join
  5992. command with an
  5993. .IR ex
  5994. command
  5995. .IR count
  5996. value. The address correction for a
  5997. .IR count
  5998. that is past the end of the edit buffer is necessary for historical
  5999. compatibility for both
  6000. .IR ex
  6001. and
  6002. .IR vi .
  6003. .SS "Mark Position"
  6004. .P
  6005. Historical practice is that only lowercase letters, plus backquote and
  6006. single-quote, could be used to mark a cursor position. POSIX.1\(hy2008 requires
  6007. conformance to historical practice, but encourages implementations to
  6008. support other characters as marks as well.
  6009. .SS "Repeat Regular Expression Find (Forward and Reverse)"
  6010. .P
  6011. Historically, the
  6012. .BR N
  6013. and
  6014. .BR n
  6015. commands could not be used as motion components for the
  6016. .BR c
  6017. command. With the exception of the
  6018. .BR cN
  6019. command, which worked if the search crossed a line boundary, the text
  6020. region would be discarded, and the user would not be in text input
  6021. mode. For consistency and simplicity of specification, POSIX.1\(hy2008 does not
  6022. permit this behavior.
  6023. .SS "Insert Empty Line (Below and Above)"
  6024. .P
  6025. Historically, counts to the
  6026. .BR O
  6027. and
  6028. .BR o
  6029. commands were used as the number of physical lines to open, if the
  6030. terminal was dumb and the
  6031. .BR slowopen
  6032. option was not set. This was intended to minimize traffic over slow
  6033. connections and repainting for dumb terminals. POSIX.1\(hy2008 does not permit
  6034. this behavior, requiring that a
  6035. .IR count
  6036. to the open command behave as for other text input commands. This
  6037. change to historical practice was made for consistency, and because a
  6038. superset of the functionality is provided by the
  6039. .BR slowopen
  6040. edit option.
  6041. .SS "Put from Buffer (Following and Before)"
  6042. .P
  6043. Historically,
  6044. .IR count s
  6045. to the
  6046. .BR p
  6047. and
  6048. .BR P
  6049. commands were ignored if the buffer was a line mode buffer, but were
  6050. (mostly) implemented as described in POSIX.1\(hy2008 if the buffer was a
  6051. character mode buffer. Because implementations exist that do not have
  6052. this limitation, and because pasting lines multiple times is generally
  6053. useful, POSIX.1\(hy2008 requires that
  6054. .IR count
  6055. be supported for all
  6056. .BR p
  6057. and
  6058. .BR P
  6059. commands.
  6060. .P
  6061. Historical implementations of
  6062. .IR vi
  6063. were widely known to have major problems in the
  6064. .BR p
  6065. and
  6066. .BR P
  6067. commands, particularly when unusual regions of text were copied into
  6068. the edit buffer. The standard developers viewed these as bugs, and they
  6069. are not permitted for consistency and simplicity of specification.
  6070. .P
  6071. Historically, a
  6072. .BR P
  6073. or
  6074. .BR p
  6075. command (or an
  6076. .IR ex
  6077. .BR put
  6078. command executed from open or visual mode) executed in an empty file,
  6079. left an empty line as the first line of the file. For consistency and
  6080. simplicity of specification, POSIX.1\(hy2008 does not permit this behavior.
  6081. .SS "Replace Character"
  6082. .P
  6083. Historically, the
  6084. .BR r
  6085. command did not correctly handle the
  6086. .IR erase
  6087. and
  6088. .IR "word erase"
  6089. characters as arguments, nor did it handle an associated
  6090. .IR count
  6091. greater than 1 with a
  6092. <carriage-return>
  6093. argument, for which it replaced
  6094. .IR count
  6095. characters with a single
  6096. <newline>.
  6097. POSIX.1\(hy2008 does not permit these inconsistencies.
  6098. .P
  6099. Historically, the
  6100. .BR r
  6101. command permitted the
  6102. <control>\(hyV
  6103. escaping of entered characters, such as
  6104. <ESC>
  6105. and the
  6106. <carriage-return>;
  6107. however, it required two leading
  6108. <control>\(hyV
  6109. characters instead of one. POSIX.1\(hy2008 requires that this be changed for
  6110. consistency with the other text input commands of
  6111. .IR vi .
  6112. .P
  6113. Historically, it is an error to enter the
  6114. .BR r
  6115. command if there are less than
  6116. .IR count
  6117. characters at or after the cursor in the line. While a reasonable and
  6118. unambiguous extension would be to permit the
  6119. .BR r
  6120. command on empty lines, it would require that too large a
  6121. .IR count
  6122. be adjusted to match the number of characters at or after the cursor
  6123. for consistency, which is sufficiently different from historical
  6124. practice to be avoided. POSIX.1\(hy2008 requires conformance to historical
  6125. practice.
  6126. .SS "Replace Characters"
  6127. .P
  6128. Historically, if there were
  6129. .BR autoindent
  6130. characters in the line on which the
  6131. .BR R
  6132. command was run, and
  6133. .BR autoindent
  6134. was set, the first
  6135. <newline>
  6136. would be properly indented and no characters would be replaced by the
  6137. <newline>.
  6138. Each additional
  6139. <newline>
  6140. would replace
  6141. .IR n
  6142. characters, where
  6143. .IR n
  6144. was the number of characters that were needed to indent the rest of the
  6145. line to the proper indentation level. This behavior is a bug and is not
  6146. permitted by POSIX.1\(hy2008.
  6147. .SS "Undo"
  6148. .P
  6149. Historical practice for cursor positioning after undoing commands was
  6150. mixed. In most cases, when undoing commands that affected a single
  6151. line, the cursor was moved to the start of added or changed text, or
  6152. immediately after deleted text. However, if the user had moved from the
  6153. line being changed, the column was either set to the first non-\c
  6154. <blank>,
  6155. returned to the origin of the command, or remained unchanged. When
  6156. undoing commands that affected multiple lines or entire lines, the
  6157. cursor was moved to the first character in the first line restored. As
  6158. an example of how inconsistent this was, a search, followed by an
  6159. .BR o
  6160. text input command, followed by an
  6161. .BR undo
  6162. would return the cursor to the location where the
  6163. .BR o
  6164. command was entered, but a
  6165. .BR cw
  6166. command followed by an
  6167. .BR o
  6168. command followed by an
  6169. .BR undo
  6170. would return the cursor to the first non-\c
  6171. <blank>
  6172. of the line. POSIX.1\(hy2008 requires the most useful of these behaviors, and
  6173. discards the least useful, in the interest of consistency and
  6174. simplicity of specification.
  6175. .SS "Yank"
  6176. .P
  6177. Historically, the
  6178. .BR yank
  6179. command did not move to the end of the motion if the motion was in the
  6180. forward direction. It moved to the end of the motion if the motion was
  6181. in the backward direction, except for the
  6182. .BR _
  6183. command, or for the
  6184. .BR G
  6185. and
  6186. .BR \(aq
  6187. commands when the end of the motion was on the current line. This was
  6188. further complicated by the fact that for a number of motion commands,
  6189. the
  6190. .BR yank
  6191. command moved the cursor but did not update the screen; for example, a
  6192. subsequent command would move the cursor from the end of the motion,
  6193. even though the cursor on the screen had not reflected the cursor
  6194. movement for the
  6195. .BR yank
  6196. command. POSIX.1\(hy2008 requires that all
  6197. .BR yank
  6198. commands associated with backward motions move the cursor to the end of
  6199. the motion for consistency, and specifically, to make
  6200. .BR \(aq
  6201. commands as motions consistent with search patterns as motions.
  6202. .SS "Yank Current Line"
  6203. .P
  6204. Some historical implementations of the
  6205. .BR Y
  6206. command did not behave as described by POSIX.1\(hy2008 when the
  6207. .BR '_' 
  6208. key was remapped because they were implemented by pushing the
  6209. .BR '_' 
  6210. key onto the input queue and reprocessing it. POSIX.1\(hy2008 does not permit
  6211. this behavior.
  6212. .SS "Redraw Window"
  6213. .P
  6214. Historically, the
  6215. .BR z
  6216. command always redrew the screen. This is permitted but not required by
  6217. POSIX.1\(hy2008, because of the frequent use of the
  6218. .BR z
  6219. command in macros such as
  6220. .BR "map n nz."
  6221. for screen positioning, instead of its use to change the screen size.
  6222. The standard developers believed that expanding or scrolling the screen
  6223. offered a better interface for users. The ability to redraw the screen
  6224. is preserved if the optional new window size is specified, and in the
  6225. <control>\(hyL
  6226. and
  6227. <control>\(hyR
  6228. commands.
  6229. .P
  6230. The semantics of
  6231. .BR z^
  6232. are confusing at best. Historical practice is that the screen before
  6233. the screen that ended with the specified line is displayed. POSIX.1\(hy2008
  6234. requires conformance to historical practice.
  6235. .P
  6236. Historically, the
  6237. .BR z
  6238. command would not display a partial line at the top or bottom of the
  6239. screen. If the partial line would normally have been displayed at the
  6240. bottom of the screen, the command worked, but the partial line was
  6241. replaced with
  6242. .BR '@' 
  6243. characters. If the partial line would normally have been displayed at
  6244. the top of the screen, the command would fail. For consistency and
  6245. simplicity of specification, POSIX.1\(hy2008 does not permit this behavior.
  6246. .P
  6247. Historically, the
  6248. .BR z
  6249. command with a line specification of 1 ignored the command. For
  6250. consistency and simplicity of specification, POSIX.1\(hy2008 does not permit this
  6251. behavior.
  6252. .P
  6253. Historically, the
  6254. .BR z
  6255. command did not set the cursor column to the first non-\c
  6256. <blank>
  6257. for the character if the first screen was to be displayed, and was
  6258. already displayed. For consistency and simplicity of specification,
  6259. POSIX.1\(hy2008 does not permit this behavior.
  6260. .SS "Input Mode Commands in vi"
  6261. .P
  6262. Historical implementations of
  6263. .IR vi
  6264. did not permit the user to erase more than a single line of input,
  6265. or to use normal erase characters such as
  6266. .IR "line erase" ,
  6267. .IR worderase ,
  6268. and
  6269. .IR erase
  6270. to erase
  6271. .BR autoindent
  6272. characters. As there exist implementations of
  6273. .IR vi
  6274. that do not have these limitations, both behaviors are permitted, but
  6275. only historical practice is required. In the case of these extensions,
  6276. .IR vi
  6277. is required to pause at the
  6278. .BR autoindent
  6279. and previous line boundaries.
  6280. .P
  6281. Historical implementations of
  6282. .IR vi
  6283. updated only the portion of the screen where the current cursor
  6284. character was displayed. For example, consider the
  6285. .IR vi
  6286. input keystrokes:
  6287. .sp
  6288. .RS 4
  6289. .nf
  6291. iabcd<escape>0C<tab>
  6292. .fi
  6293. .P
  6294. .RE
  6295. .P
  6296. Historically, the
  6297. <tab>
  6298. would overwrite the characters
  6299. .BR \(dqabcd\(dq 
  6300. when it was displayed. Other implementations replace only the
  6301. .BR 'a' 
  6302. character with the
  6303. <tab>,
  6304. and then push the rest of the characters ahead of the cursor. Both
  6305. implementations have problems. The historical implementation is
  6306. probably visually nicer for the above example; however, for the
  6307. keystrokes:
  6308. .sp
  6309. .RS 4
  6310. .nf
  6312. iabcd<ESC>0R<tab><ESC>
  6313. .fi
  6314. .P
  6315. .RE
  6316. .P
  6317. the historical implementation results in the string
  6318. .BR \(dqbcd\(dq 
  6319. disappearing and then magically reappearing when the
  6320. <ESC>
  6321. character is entered. POSIX.1\(hy2008 requires the former behavior when
  6322. overwriting erase-columns\(emthat is, overwriting characters that are no
  6323. longer logically part of the edit buffer\(emand the latter behavior
  6324. otherwise.
  6325. .P
  6326. Historical implementations of
  6327. .IR vi
  6328. discarded the
  6329. <control>\(hyD
  6330. and
  6331. <control>\(hyT
  6332. characters when they were entered at places where their command
  6333. functionality was not appropriate. POSIX.1\(hy2008 requires that the
  6334. <control>\(hyT
  6335. functionality always be available, and that
  6336. <control>\(hyD
  6337. be treated as any other key when not operating on
  6338. .BR autoindent
  6339. characters.
  6340. .SS "NUL"
  6341. .P
  6342. Some historical implementations of
  6343. .IR vi
  6344. limited the number of characters entered using the NUL input character
  6345. to 256 bytes. POSIX.1\(hy2008 permits this limitation; however, implementations
  6346. are encouraged to remove this limit.
  6347. .SS "<control>\(hyD"
  6348. .P
  6349. See also Rationale for the input mode command
  6350. <newline>.
  6351. The hidden assumptions in the
  6352. <control>\(hyD
  6353. command (and in the
  6354. .IR vi
  6355. .BR autoindent
  6356. specification in general) is that
  6357. <space>
  6358. characters take up a single column on the screen and that
  6359. <tab>
  6360. characters are comprised of an integral number of
  6361. <space>
  6362. characters.
  6363. .SS "<newline>"
  6364. .P
  6365. Implementations are permitted to rewrite
  6366. .BR autoindent
  6367. characters in the line when
  6368. <newline>,
  6369. <carriage-return>,
  6370. <control>\(hyD,
  6371. and
  6372. <control>\(hyT
  6373. are entered, or when the
  6374. .BR shift
  6375. commands are used, because historical implementations have both done so
  6376. and found it necessary to do so. For example, a
  6377. <control>\(hyD
  6378. when the cursor is preceded by a single
  6379. <tab>,
  6380. with
  6381. .BR tabstop
  6382. set to 8, and
  6383. .BR shiftwidth
  6384. set to 3, will result in the
  6385. <tab>
  6386. being replaced by several
  6387. <space>
  6388. characters.
  6389. .SS "<control>\(hyT"
  6390. .P
  6391. See also the Rationale for the input mode command
  6392. <newline>.
  6393. Historically,
  6394. <control>\(hyT
  6395. only worked if no non-\c
  6396. <blank>
  6397. characters had yet been input in the current input line. In addition,
  6398. the characters inserted by
  6399. <control>\(hyT
  6400. were treated as
  6401. .BR autoindent
  6402. characters, and could not be erased using normal user erase characters.
  6403. Because implementations exist that do not have these limitations, and
  6404. as moving to a column boundary is generally useful, POSIX.1\(hy2008 requires that
  6405. both limitations be removed.
  6406. .SS "<control>\(hyV"
  6407. .P
  6408. Historically,
  6409. .IR vi
  6410. used
  6411. .BR ^V ,
  6412. regardless of the value of the literal-next character of the terminal.
  6413. POSIX.1\(hy2008 requires conformance to historical practice.
  6414. .P
  6415. The uses described for
  6416. <control>\(hyV
  6417. can also be accomplished with
  6418. <control>\(hyQ,
  6419. which is useful on terminals that use
  6420. <control>\(hyV
  6421. for the down-arrow function. However, most historical implementations
  6422. use
  6423. <control>\(hyQ
  6424. for the
  6425. .IR termios
  6426. START character, so the editor will generally not receive the
  6427. <control>\(hyQ
  6428. unless
  6429. .BR "stty ixon"
  6430. mode is set to off. (In addition, some historical implementations of
  6431. .IR vi
  6432. explicitly set
  6433. .BR ixon
  6434. mode to on, so it was difficult for the user to set it to off.) Any of
  6435. the command characters described in POSIX.1\(hy2008 can be made ineffective by
  6436. their selection as
  6437. .IR termios
  6438. control characters, using the
  6439. .IR stty
  6440. utility or other methods described in the System Interfaces volume of POSIX.1\(hy2017.
  6441. .SS "<ESC>"
  6442. .P
  6443. Historically, SIGINT alerted the terminal when used to end input
  6444. mode. This behavior is permitted, but not required, by POSIX.1\(hy2008.
  6445. .SH "FUTURE DIRECTIONS"
  6446. None.
  6447. .SH "SEE ALSO"
  6448. .IR "\fIed\fR\^",
  6449. .IR "\fIex\fR\^",
  6450. .IR "\fIstty\fR\^"
  6451. .P
  6452. The Base Definitions volume of POSIX.1\(hy2017,
  6453. .IR "Section 12.2" ", " "Utility Syntax Guidelines"
  6454. .\"
  6455. .SH COPYRIGHT
  6456. Portions of this text are reprinted and reproduced in electronic form
  6457. from IEEE Std 1003.1-2017, Standard for Information Technology
  6458. -- Portable Operating System Interface (POSIX), The Open Group Base
  6459. Specifications Issue 7, 2018 Edition,
  6460. Copyright (C) 2018 by the Institute of
  6461. Electrical and Electronics Engineers, Inc and The Open Group.
  6462. In the event of any discrepancy between this version and the original IEEE and
  6463. The Open Group Standard, the original IEEE and The Open Group Standard
  6464. is the referee document. The original Standard can be obtained online at
  6465. http://www.opengroup.org/unix/online.html .
  6466. .PP
  6467. Any typographical or formatting errors that appear
  6468. in this page are most likely
  6469. to have been introduced during the conversion of the source files to
  6470. man page format. To report such errors, see
  6471. https://www.kernel.org/doc/man-pages/reporting_bugs.html .