X-Git-Url: http://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=man%2Fcurs_add_wch.3x;h=01fd9225e0217f5baf7b6a931fe71c2c60c17133;hp=fae59ae0b6cdeac3142dc6471dbe5e1077c29ab0;hb=HEAD;hpb=46722468f47c2b77b3987729b4bcf2321cccfd01 diff --git a/man/curs_add_wch.3x b/man/curs_add_wch.3x index fae59ae0..502425af 100644 --- a/man/curs_add_wch.3x +++ b/man/curs_add_wch.3x @@ -1,5 +1,7 @@ +'\" t .\"*************************************************************************** -.\" Copyright (c) 2001,2002 Free Software Foundation, Inc. * +.\" Copyright 2019-2023,2024 Thomas E. Dickey * +.\" Copyright 2001-2015,2017 Free Software Foundation, Inc. * .\" * .\" Permission is hereby granted, free of charge, to any person obtaining a * .\" copy of this software and associated documentation files (the * @@ -26,109 +28,514 @@ .\" authorization. * .\"*************************************************************************** .\" -.\" $Id: curs_add_wch.3x,v 1.4 2002/02/16 22:28:43 tom Exp $ -.TH curs_add_wch 3X "" +.\" $Id: curs_add_wch.3x,v 1.63 2024/05/11 21:31:45 tom Exp $ +.TH curs_add_wch 3X 2024-05-11 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "Library calls" +.ie \n(.g \{\ +.ds `` \(lq +.ds '' \(rq +.\} +.el \{\ +.ie t .ds `` `` +.el .ds `` "" +.ie t .ds '' '' +.el .ds '' "" +.\} +. +.de bP +.ie n .IP \(bu 4 +.el .IP \(bu 2 +.. .SH NAME -\fBadd_wch\fP, -\fBwadd_wch\fP, -\fBmvadd_wch\fP, -\fBmvwadd_wch\fP, -\fBecho_wchar\fP, -\fBwecho_wchar\fP - add a complex character and rendition to a \fBcurses\fR window, then advance the cursor +\fB\%add_wch\fP, +\fB\%wadd_wch\fP, +\fB\%mvadd_wch\fP, +\fB\%mvwadd_wch\fP, +\fB\%echo_wchar\fP, +\fB\%wecho_wchar\fP \- +add a \fIcurses\fR complex character to a window, possibly advancing the cursor .SH SYNOPSIS +.nf +\fB#include .PP -\fB#include \fP -.sp -.B "int add_wch( const cchar_t *\fIwch\fB );" -.br -.B "int wadd_wch( WINDOW *\fIwin\fP, const cchar_t *\fIwch\fB );" -.br -.B "int mvadd_wch( int \fIy\fP, int \fIx\fP, const cchar_t *\fIwch\fB );" -.br -.B "int mvwadd_wch( WINDOW *\fIwin\fP, int \fIy\fP, int \fIx\fP, const cchar_t *\fIwch\fB );" -.br -.B "int echo_wchar( const cchar_t *\fIwch\fB );" -.br -.B "int wecho_wchar( WINDOW *\fIwin\fP, const cchar_t *\fIwch\fB );" -.br +\fBint add_wch(const cchar_t *\fIwch\fP); +\fBint wadd_wch(WINDOW *\fIwin\fP, const cchar_t *\fIwch\fP); +\fBint mvadd_wch(int \fIy\fP, int \fIx\fP, const cchar_t *\fIwch\fP); +\fBint mvwadd_wch(WINDOW *\fIwin\fP, int \fIy\fP, int \fIx\fP, const cchar_t *\fIwch\fP); +.PP +\fBint echo_wchar(const cchar_t *\fIwch\fP); +\fBint wecho_wchar(WINDOW *\fIwin\fP, const cchar_t *\fIwch\fP); +.fi .SH DESCRIPTION +.SS wadd_wch +.B \%wadd_wch +writes the complex character +.I wch +to the window +.IR win "," +then may advance the cursor position, +analogously to the standard C library's \fI\%putwchar\fP(3). +\fB\%ncurses\fP(3X) describes the variants of this function. .PP -The -\fBadd_wch\fP, -\fBwadd_wch\fP, -\fBmvadd_wch\fP, and -\fBmvwadd_wch\fP -functions put the complex character \fIwch\fP into the given -window at its current position, -which is then advanced. -These functions perform -wrapping and special-character processing as follows: -.TP 5 -- -If \fIwch\fP refers to a spacing character, -then any previous character at that location is removed. -A new character specified by \fIwch\fP is -placed at that location with rendition specified by \fIwch\fP. -The cursor then advances to -the next spacing character on the screen. -.TP 5 -- -If \fIwch\fP refers to a non-spacing character, -all previous characters at that location are preserved. -The non-spacing characters of \fIwch\fP -are added to the spacing complex character, -and the rendition specified by \fIwch\fP is ignored. -.TP 5 -- -If the character part of \fIwch\fP is -a tab, newline, backspace or other control character, -the window is updated and the cursor moves as if \fBaddch\fR(3X) were called. -.PP -The \fBecho_wchar\fP -function is functionally equivalent to a call to -\fBadd_wch\fP -followed by a call to -\fBrefresh\fP. -Similarly, the -\fBwecho_wchar\fP -is functionally equivalent to a call to -\fBwadd_wch\fP -followed by a call to -\fBwrefresh\fP. -The knowledge -that only a single character is being output is taken into consideration and, -for non-control characters, a considerable performance gain might be seen -by using the *\fBecho\fP* functions instead of their equivalents. -.SH RETURN VALUES -.PP -All routines return the integer \fBERR\fR upon failure and \fBOK\fR on success. -.SH NOTES +Much behavior depends on whether the wide characters in +.I wch +are spacing or non-spacing; +see subsection \*(``Complex Characters\*('' below. +.bP +If +.I wch +contains a spacing character, +then any character at the cursor is first removed. +The complex character +.IR wch "," +with its attributes and color pair identifier, +becomes the +.I base +of the +.IR "active complex character" "." +.bP +If +.I wch +contains only non-spacing characters, +.\" XXX: see wadd_wch_literal (the beginning of the array may be nonspacing) +they are combined with the active complex character. +.I curses +ignores its attributes and color pair identifier, +and does not advance the cursor. +.PP +Further non-spacing characters added with +.B \%wadd_wch +are not written at the new cursor position but combine with the active +complex character until another spacing character is written to the +window or the cursor is moved. +.PP +If advancement occurs at the right margin, +.bP +the cursor automatically wraps to the beginning of the next line, +then, +.bP +if it was at the bottom of the scrolling region, +and if \fB\%scrollok\fP(3X) is enabled for +.IR win , +the scrolling region scrolls up one line. +.PP +If +.I wch +is a +backspace, +carriage return, +line feed, +or +tab, +the cursor moves appropriately within the window. +.bP +Backspace moves the cursor one character left; +at the left margin of a window, +it does nothing. +.bP +Carriage return moves the cursor to the left margin on the current line +of the window. +.bP +Line feed does a \fB\%clrtoeol\fP(3X), +then advances as if from the right margin. +.bP +Tab advances the cursor to the next tab stop +(possibly on the next line); +these are placed at every eighth column by default. +Alter the tab interval with the +.B \%TABSIZE +extension; +see \fB\%curs_variables\fP(3X). +.PP +If +.I wch +is any other nonprintable character, +it is drawn in printable form using the same convention as +\fB\%wunctrl\fP(3X). +.PP +Calling \fB\%win_wch\fP(3X) on the location of a nonprintable character +does not return the character itself, +but its \fB\%wunctrl\fP(3X) representation. +.SS wecho_wchar +.B \%echo_wchar +and +.B \%wecho_wchar +are equivalent to calling +.RB \%( w ) add_wch +followed by +.RB \%( w ) refresh . +.I curses +interprets these functions as a hint that only a single (complex) +character is being output; +for non-control characters, +a considerable performance gain may be enjoyed by employing them. +.\" TODO: Combine the following with the "Line Drawing" subsection of +.\" terminfo(5) and replace this with a cross reference there. +.SS "Forms-Drawing Characters" +.I curses +defines macros starting with +.B \%WACS_ +that can be used with +.B \%wadd_wch +to write line-drawing and other special characters to the screen. +.I \%ncurses +terms these +.I "forms-drawing characters." +The ACS default listed below is used if the +.B \%acs_chars +.RB ( \%acsc ) +.I \%term\%info +capability does not define a terminal-specific replacement for it, +or if the terminal and locale configuration requires Unicode to access +these characters but the library is unable to use Unicode. +The \*(``acsc char\*('' column corresponds to how the characters are +specified in the +.B \%acs_chars +.RB ( \%acsc ) +string capability, +and the characters in it may appear on the screen if the terminal type's +database entry incorrectly advertises ACS support. +The name \*(``ACS\*('' originates in the Alternate Character Set feature +of the DEC VT100 terminal. +.PP +.TS +Lb Lb Lb Lb Lb +Lb Lb Lb Lb Lb +Lb L L L Lx. +\& Unicode ACS acsc \& +Symbol Default Default char Glyph Name +_ +WACS_BLOCK 0x25ae # 0 T{ +solid square block +T} +WACS_BOARD 0x2592 # h board of squares +WACS_BTEE 0x2534 + v bottom tee +WACS_BULLET 0x00b7 o ~ bullet +WACS_CKBOARD 0x2592 : a T{ +checker board (stipple) +T} +WACS_DARROW 0x2193 v . T{ +arrow pointing down +T} +WACS_DEGREE 0x00b0 ' f degree symbol +WACS_DIAMOND 0x25c6 + \(ga diamond +WACS_GEQUAL 0x2265 > > T{ +greater-than-or-equal-to +T} +WACS_HLINE 0x2500 \- q horizontal line +WACS_LANTERN 0x2603 # i lantern symbol +WACS_LARROW 0x2190 < , T{ +arrow pointing left +T} +WACS_LEQUAL 0x2264 < y T{ +less-than-or-equal-to +T} +WACS_LLCORNER 0x2514 + m T{ +lower left-hand corner +T} +WACS_LRCORNER 0x2518 + j T{ +lower right-hand corner +T} +WACS_LTEE 0x2524 + t left tee +WACS_NEQUAL 0x2260 ! | not-equal +WACS_PI 0x03c0 * { greek pi +WACS_PLMINUS 0x00b1 # g plus/minus +WACS_PLUS 0x253c + n plus +WACS_RARROW 0x2192 > + T{ +arrow pointing right +T} +WACS_RTEE 0x251c + u right tee +WACS_S1 0x23ba \- o scan line 1 +WACS_S3 0x23bb \- p scan line 3 +WACS_S7 0x23bc \- r scan line 7 +WACS_S9 0x23bd \&_ s scan line 9 +WACS_STERLING 0x00a3 f } T{ +pound-sterling symbol +T} +WACS_TTEE 0x252c + w top tee +WACS_UARROW 0x2191 ^ \- T{ +arrow pointing up +T} +WACS_ULCORNER 0x250c + l T{ +upper left-hand corner +T} +WACS_URCORNER 0x2510 + k T{ +upper right-hand corner +T} +WACS_VLINE 0x2502 | x vertical line +.TE +.PP +The wide-character configuration of \fI\%ncurses\fP also defines symbols +for thick lines (\fBacsc\fP \*(``J\*('' to \*(``V\*(''): +.PP +.TS +Lb Lb Lb Lb Lb +Lb Lb Lb Lb Lb +Lb L L L Lx. +\& Unicode ASCII acsc \& +ACS Name Default Default Char Glyph Name +_ +WACS_T_BTEE 0x253b + V T{ +thick tee pointing up +T} +WACS_T_HLINE 0x2501 - Q T{ +thick horizontal line +T} +WACS_T_LLCORNER 0x2517 + M T{ +thick lower left corner +T} +WACS_T_LRCORNER 0x251b + J T{ +thick lower right corner +T} +WACS_T_LTEE 0x252b + T T{ +thick tee pointing right +T} +WACS_T_PLUS 0x254b + N T{ +thick large plus +T} +WACS_T_RTEE 0x2523 + U T{ +thick tee pointing left +T} +WACS_T_TTEE 0x2533 + W T{ +thick tee pointing down +T} +WACS_T_ULCORNER 0x250f + L T{ +thick upper left corner +T} +WACS_T_URCORNER 0x2513 + K T{ +thick upper right corner +T} +WACS_T_VLINE 0x2503 | X T{ +thick vertical line +T} +.TE .PP -Note that -\fBadd_wch\fP, -\fBmvadd_wch\fP, -\fBmvwadd_wch\fP, and -\fBecho_wchar\fP -may be macros. +and for double-lines (\fBacsc\fP \*(``A\*('' to \*(``I\*(''): +.PP +.TS +Lb Lb Lb Lb Lb +Lb Lb Lb Lb Lb +Lb L L L Lx. +\& Unicode ASCII acsc \& +ACS Name Default Default Char Glyph Name +_ +WACS_D_BTEE 0x2569 + H T{ +double tee pointing up +T} +WACS_D_HLINE 0x2550 - R T{ +double horizontal line +T} +WACS_D_LLCORNER 0x255a + D T{ +double lower left corner +T} +WACS_D_LRCORNER 0x255d + A T{ +double lower right corner +T} +WACS_D_LTEE 0x2560 + F T{ +double tee pointing right +T} +WACS_D_PLUS 0x256c + E T{ +double large plus +T} +WACS_D_RTEE 0x2563 + G T{ +double tee pointing left +T} +WACS_D_TTEE 0x2566 + I T{ +double tee pointing down +T} +WACS_D_ULCORNER 0x2554 + C T{ +double upper left corner +T} +WACS_D_URCORNER 0x2557 + B T{ +double upper right corner +T} +WACS_D_VLINE 0x2551 | Y T{ +double vertical line +T} +.TE +.PP +Unicode's descriptions for these characters differs slightly from +\fI\%ncurses\fP, +by introducing the term \*(``light\*('' (along with less important details). +Here are its descriptions for the normal, thick, and double horizontal lines: +.bP +U+2500 BOX DRAWINGS LIGHT HORIZONTAL +.bP +U+2501 BOX DRAWINGS HEAVY HORIZONTAL +.bP +U+2550 BOX DRAWINGS DOUBLE HORIZONTAL +.SH RETURN VALUE +These functions return +.B OK +on success and +.B ERR +on failure. +In +.IR \%ncurses , +.B \%wadd_wch +returns +.B ERR +if +.bP +.I win +is +.BR NULL "," +.bP +wrapping to a new line is impossible because \fB\%scrollok\fP(3X) has +not been called on +.I win +when writing to its bottom right location is attempted, +or +.bP +it is not possible to add a complete character at the cursor position. +.PP +Functions prefixed with \*(``mv\*('' first perform cursor movement and +fail if the position +.RI ( y , +.IR x ) +is outside the window boundaries. +.SH NOTES +.BR add_wch "," +.BR mvadd_wch "," +.BR mvwadd_wch "," +and +.B echo_wchar +may be implemented as macros. +.SH EXTENSIONS +.SS TABSIZE +The +.B TABSIZE +variable is implemented in SVr4 and other versions of +.IR curses , +but is not specified by X/Open Curses +(see \fBcurs_variables\fP(3X)). .SH PORTABILITY +These functions are described in X/Open Curses, Issue 4. +It specifies no error conditions for them. +.PP +SVr4 +.I curses +describes a successful return value only as +\*(``an integer value other than +.BR ERR \*(''. +.PP +The defaults specified for forms-drawing characters apply in the POSIX +locale. +X/Open Curses makes it clear that the WACS_ symbols should be defined as +a pointer to \fBcchar_t\fP data, e.g., in the discussion of \fBborder_set\fP. +A few implementations are problematic: +.bP +NetBSD curses defines the symbols as a \fBwchar_t\fP within a \fBcchar_t\fP. +.bP +HP-UX curses equates some of the \fBACS_\fP symbols +to the analogous \fBWACS_\fP symbols as if the \fBACS_\fP symbols were +wide characters. +The misdefined symbols are the arrows +and other symbols which are not used for line-drawing. +.PP +X/Open Curses does not specify symbols for thick- or double-lines. +SVr4 curses implementations defined their line-drawing symbols in +terms of intermediate symbols. +This implementation extends those symbols, providing new definitions +which are not in the SVr4 implementations. +.PP +Not all Unicode-capable terminals provide support for VT100-style +alternate character sets (i.e., the \fBacsc\fP capability), +with their corresponding line-drawing characters. +X/Open Curses did not address the aspect of integrating Unicode with +line-drawing characters. +Existing implementations of Unix curses (AIX, HP-UX, Solaris) +use only the \fBacsc\fP character-mapping to provide this feature. +As a result, those implementations can only use single-byte line-drawing +characters. +\fI\%ncurses\fP 5.3 (2002) provided a table of Unicode values to solve +these problems. +NetBSD curses incorporated that table in 2010. +.PP +In this implementation, the Unicode values are used instead of the +terminal description's \fBacsc\fP mapping as discussed in +\fB\%ncurses\fP(3X) for the environment variable +\fINCURSES_NO_UTF8_ACS\fP. +In contrast, for the same cases, the line-drawing characters +described in \fB\%addch\fP(3X) will use only the ASCII default values. +.PP +Having Unicode available does not solve all of the problems with +line-drawing for curses: +.bP +The closest Unicode equivalents to the +VT100 graphics \fIS1\fP, \fIS3\fP, \fIS7\fP and \fIS9\fP +frequently are not displayed at +the regular intervals which the terminal used. +.bP +The \fIlantern\fP is a special case. +It originated with the AT&T 4410 terminal in the early 1980s. +There is no accessible documentation depicting the lantern symbol +on the AT&T terminal. +.IP +Lacking documentation, most readers assume that a \fIstorm lantern\fP +was intended. +But there are several possibilities, all with problems. +.IP +Unicode 6.0 (2010) does provide two lantern symbols: U+1F383 and U+1F3EE. +Those were not available in 2002, and are irrelevant since +they lie outside the BMP and as a result are not generally available +in terminals. +They are not storm lanterns, in any case. +.IP +Most \fIstorm lanterns\fP have a tapering glass chimney +(to guard against tipping); +some have a wire grid protecting the chimney. +.IP +For the tapering appearance, \[u2603] U+2603 was adequate. +In use on a terminal, no one can tell what the image represents. +Unicode calls it a snowman. +.IP +Others have suggested these alternatives: +\[sc] U+00A7 (section mark), +\[u0398] U+0398 (theta), +\[u03A6] U+03A6 (phi), +\[u03B4] U+03B4 (delta), +\[u2327] U+2327 (x in a rectangle), +\[u256C] U+256C (forms double vertical and horizontal), and +\[u2612] U+2612 (ballot box with x). +.SS "Complex Characters" +The complex character type +.I \%cchar_t +can store more than one wide character +.RI ( \%wchar_t ). +X/Open Curses does not mention this possibility, +specifying behavior only where +.I wch +is a single character, +either spacing or non-spacing. .PP -All these functions are described in the XSI Curses standard, Issue 4. -The defaults specified for forms-drawing characters apply in the POSIX locale. +.I \%ncurses +assumes that +.I wch +is constructed using \fB\%setcchar\fP(3X), +and in turn that the result +.bP +contains at most one spacing character at the beginning of its list of +wide characters, +and zero or more non-spacing characters, +or +.bP +holds one non-spacing character. .PP -XSI documents constants beginning with \fBWACS_\fP which are used for -line-drawing. -Those are not currently implemented in \fBncurses\fP. +In the latter case, +.I \%ncurses +adds the non-spacing character to the active complex character. .SH SEE ALSO +\fB\%curs_addch\fP(3X) describes comparable functions of the +.I \%ncurses +library in its non-wide-character configuration. .PP -\fBcurses\fR(3X), -\fBcurs_attr_get\fR(3X), -\fBcurs_clear\fR(3X), -\fBcurs_outopts\fR(3X), -\fBcurs_refresh\fR(3X), -\fBputwc\fR(3) -.\"# -.\"# The following sets edit modes for GNU EMACS -.\"# Local Variables: -.\"# mode:nroff -.\"# fill-column:79 -.\"# End: +\fB\%curses\fP(3X), +\fB\%curs_addwstr\fP(3X), +\fB\%curs_add_wchstr\fP(3X), +\fB\%curs_attr\fP(3X), +\fB\%curs_clear\fP(3X), +\fB\%curs_getcchar\fP(3X), +\fB\%curs_outopts\fP(3X), +\fB\%curs_refresh\fP(3X), +\fB\%curs_variables\fP(3X), +\fB\%putwc\fP(3)