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diff --git a/doc/html/man/curs_addch.3x.html b/doc/html/man/curs_addch.3x.html index ba13e2a725a3..0a0622e39af3 100644 --- a/doc/html/man/curs_addch.3x.html +++ b/doc/html/man/curs_addch.3x.html @@ -1,7 +1,7 @@ -<!-- +<!-- * t **************************************************************************** - * Copyright 2018-2019,2020 Thomas E. Dickey * + * Copyright 2018-2023,2024 Thomas E. Dickey * * Copyright 1998-2015,2017 Free Software Foundation, Inc. * * * * Permission is hereby granted, free of charge, to any person obtaining a * @@ -28,28 +28,28 @@ * sale, use or other dealings in this Software without prior written * * authorization. * **************************************************************************** - * @Id: curs_addch.3x,v 1.55 2020/10/24 09:12:31 tom Exp @ + * @Id: curs_addch.3x,v 1.85 2024/04/20 19:03:47 tom Exp @ --> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"> <HTML> <HEAD> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <meta name="generator" content="Manpage converted by man2html - see https://invisible-island.net/scripts/readme.html#others_scripts"> -<TITLE>curs_addch 3x</TITLE> +<TITLE>curs_addch 3x 2024-04-20 ncurses 6.5 Library calls</TITLE> <link rel="author" href="mailto:bug-ncurses@gnu.org"> -<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> + </HEAD> <BODY> -<H1 class="no-header">curs_addch 3x</H1> +<H1 class="no-header">curs_addch 3x 2024-04-20 ncurses 6.5 Library calls</H1> <PRE> -<STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG> <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG> +<STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG> Library calls <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG> </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE> - <STRONG>addch</STRONG>, <STRONG>waddch</STRONG>, <STRONG>mvaddch</STRONG>, <STRONG>mvwaddch</STRONG>, <STRONG>echochar</STRONG>, <STRONG>wechochar</STRONG> - add a character - (with attributes) to a <STRONG>curses</STRONG> window, then advance the cursor + <STRONG>addch</STRONG>, <STRONG>waddch</STRONG>, <STRONG>mvaddch</STRONG>, <STRONG>mvwaddch</STRONG>, <STRONG>echochar</STRONG>, <STRONG>wechochar</STRONG> - add a <EM>curses</EM> + character to a window and advance the cursor </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE> @@ -66,239 +66,241 @@ </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE> -</PRE><H3><a name="h3-Adding-characters">Adding characters</a></H3><PRE> - The <STRONG>addch</STRONG>, <STRONG>waddch</STRONG>, <STRONG>mvaddch</STRONG> and <STRONG>mvwaddch</STRONG> routines put the character <EM>ch</EM> - into the given window at its current window position, which is then - advanced. They are analogous to <STRONG>putchar(3)</STRONG> in <STRONG>stdio(3)</STRONG>. If the - advance is at the right margin: +</PRE><H3><a name="h3-Adding-Characters">Adding Characters</a></H3><PRE> + <STRONG>waddch</STRONG> puts the character <EM>ch</EM> at the cursor position of window <EM>win</EM>, then + advances the cursor position, analogously to the standard C library's + <STRONG>putchar(3)</STRONG>. <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG> describes the variants of this function. - <STRONG>o</STRONG> The cursor automatically wraps to the beginning of the next line. + If advancement occurs at the right margin, - <STRONG>o</STRONG> At the bottom of the current scrolling region, and if <STRONG>scrollok</STRONG> is - enabled, the scrolling region is scrolled up one line. + <STRONG>o</STRONG> the cursor automatically wraps to the beginning of the next line; + and - <STRONG>o</STRONG> If <STRONG>scrollok</STRONG> is not enabled, writing a character at the lower right - margin succeeds. However, an error is returned because it is not - possible to wrap to a new line + <STRONG>o</STRONG> at the bottom of the current scrolling region, and if <STRONG><A HREF="scrollok.3x.html">scrollok(3x)</A></STRONG> + is enabled for <EM>win</EM>, the scrolling region scrolls up one line. - If <EM>ch</EM> is a tab, newline, carriage return or backspace, the cursor is - moved appropriately within the window: + If <EM>ch</EM> is a backspace, carriage return, line feed, or tab, the cursor + moves appropriately within the window. - <STRONG>o</STRONG> Backspace moves the cursor one character left; at the left edge of - a window it does nothing. + <STRONG>o</STRONG> Backspace moves the cursor one character left; at the left margin + of a window, it does nothing. - <STRONG>o</STRONG> Carriage return moves the cursor to the window left margin on the - current line. + <STRONG>o</STRONG> Carriage return moves the cursor to the left margin on the current + line of the window. - <STRONG>o</STRONG> Newline does a <STRONG>clrtoeol</STRONG>, then moves the cursor to the window left - margin on the next line, scrolling the window if on the last line. + <STRONG>o</STRONG> Line feed does a <STRONG><A HREF="curs_clear.3x.html">clrtoeol(3x)</A></STRONG>, then moves the cursor to the left + margin on the next line of the window, and if <STRONG><A HREF="scrollok.3x.html">scrollok(3x)</A></STRONG> is + enabled for <EM>win</EM>, scrolls the window if the cursor was already on + the last line. - <STRONG>o</STRONG> Tabs are considered to be at every eighth column. The tab interval - may be altered by setting the <STRONG>TABSIZE</STRONG> variable. + <STRONG>o</STRONG> 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 <STRONG>TABSIZE</STRONG> extension; see + <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>. If <EM>ch</EM> is any other nonprintable character, it is drawn in printable - form, i.e., the <STRONG>^</STRONG><EM>X</EM> notation used by <STRONG><A HREF="unctrl.3x.html">unctrl(3x)</A></STRONG>. Calling <STRONG>winch</STRONG> after - adding a nonprintable character does not return the character itself, - but instead returns the printable representation of the character. - - Video attributes can be combined with a character argument passed to - <STRONG>addch</STRONG> or related functions by logical-ORing them into the character. - (Thus, text, including attributes, can be copied from one place to - another using <STRONG><A HREF="curs_inch.3x.html">inch(3x)</A></STRONG> and <STRONG>addch</STRONG>.) See the <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG> page for - values of predefined video attribute constants that can be usefully - OR'ed into characters. - - -</PRE><H3><a name="h3-Echoing-characters">Echoing characters</a></H3><PRE> - The <STRONG>echochar</STRONG> and <STRONG>wechochar</STRONG> routines are equivalent to a call to <STRONG>addch</STRONG> - followed by a call to <STRONG><A HREF="curs_refresh.3x.html">refresh(3x)</A></STRONG>, or a call to <STRONG>waddch</STRONG> followed by a - call to <STRONG>wrefresh</STRONG>. The knowledge that only a single character is being - output is used and, for non-control characters, a considerable - performance gain may be seen by using these routines instead of their - equivalents. - - -</PRE><H3><a name="h3-Line-Graphics">Line Graphics</a></H3><PRE> - The following variables may be used to add line drawing characters to - the screen with routines of the <STRONG>addch</STRONG> family. The default character - listed below is used if the <STRONG>acsc</STRONG> capability does not define a terminal- - specific replacement for it, or if the terminal and locale - configuration requires Unicode but the library is unable to use - Unicode. - - The names are taken from VT100 nomenclature. - - <STRONG>ACS</STRONG> <STRONG>ACS</STRONG> <STRONG>acsc</STRONG> <STRONG>Glyph</STRONG> - <STRONG>Name</STRONG> <STRONG>Default</STRONG> <STRONG>char</STRONG> <STRONG>Name</STRONG> - --------------------------------------------------------- - ACS_BLOCK # 0 solid square block - ACS_BOARD # h board of squares - ACS_BTEE + v bottom tee - ACS_BULLET o ~ bullet - ACS_CKBOARD : a checker board (stipple) - ACS_DARROW v . arrow pointing down - ACS_DEGREE ' f degree symbol - ACS_DIAMOND + ` diamond - ACS_GEQUAL > > greater-than-or-equal-to - ACS_HLINE - q horizontal line - ACS_LANTERN # i lantern symbol - ACS_LARROW < , arrow pointing left - ACS_LEQUAL < y less-than-or-equal-to - ACS_LLCORNER + m lower left-hand corner - ACS_LRCORNER + j lower right-hand corner - ACS_LTEE + t left tee - ACS_NEQUAL ! | not-equal - ACS_PI * { greek pi - ACS_PLMINUS # g plus/minus - ACS_PLUS + n plus - ACS_RARROW > + arrow pointing right - ACS_RTEE + u right tee - ACS_S1 - o scan line 1 - ACS_S3 - p scan line 3 - ACS_S7 - r scan line 7 - ACS_S9 _ s scan line 9 - ACS_STERLING f } pound-sterling symbol - ACS_TTEE + w top tee - ACS_UARROW ^ - arrow pointing up - ACS_ULCORNER + l upper left-hand corner - ACS_URCORNER + k upper right-hand corner - ACS_VLINE | x vertical line + form, using the same convention as <STRONG><A HREF="unctrl.3x.html">unctrl(3x)</A></STRONG>. + + Calling <STRONG><A HREF="curs_inch.3x.html">winch(3x)</A></STRONG> on the location of a nonprintable character does not + return the character itself, but its <STRONG><A HREF="unctrl.3x.html">unctrl(3x)</A></STRONG> representation. + + <EM>ch</EM> may contain rendering and/or color attributes, and others can be + combined with the parameter by logically "or"ing with it. (A character + with its attributes can be copied from place to place using <STRONG><A HREF="curs_inch.3x.html">winch(3x)</A></STRONG> + and <STRONG>waddch</STRONG>.) See <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG> for values of predefined video + attribute constants that can be usefully "or"ed with characters. + + +</PRE><H3><a name="h3-Echoing-Characters">Echoing Characters</a></H3><PRE> + <STRONG>echochar</STRONG> and <STRONG>wechochar</STRONG> are equivalent to calling (<STRONG>w</STRONG>)<STRONG>addch</STRONG> followed by + (<STRONG>w</STRONG>)<STRONG>refresh</STRONG>. <EM>curses</EM> interprets these functions as a hint that only a + single character is being output; for non-control characters, a + considerable performance gain may be enjoyed by employing them. + + +</PRE><H3><a name="h3-Forms-Drawing-Characters">Forms-Drawing Characters</a></H3><PRE> + <EM>curses</EM> defines macros starting with <STRONG>ACS_</STRONG> that can be used with <STRONG>waddch</STRONG> + to write line-drawing and other special characters to the screen. + <EM>ncurses</EM> terms these <EM>forms-drawing</EM> <EM>characters.</EM> The ACS default listed + below is used if the <STRONG>acs_chars</STRONG> (<STRONG>acsc</STRONG>) <EM>terminfo</EM> 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 <STRONG>acs_chars</STRONG> string + capability, and the characters in it may appear on the screen if the + terminal's database entry incorrectly advertises ACS support. The name + "ACS" originates in the Alternate Character Set feature of the DEC + VT100 terminal. + + <STRONG>ACS</STRONG> <STRONG>acsc</STRONG> + <STRONG>Symbol</STRONG> <STRONG>Default</STRONG> <STRONG>char</STRONG> <STRONG>Glyph</STRONG> <STRONG>Name</STRONG> + ------------------------------------------------------------------------ + <STRONG>ACS_BLOCK</STRONG> # 0 solid square block + <STRONG>ACS_BOARD</STRONG> # h board of squares + <STRONG>ACS_BTEE</STRONG> + v bottom tee + <STRONG>ACS_BULLET</STRONG> o ~ bullet + <STRONG>ACS_CKBOARD</STRONG> : a checker board (stipple) + <STRONG>ACS_DARROW</STRONG> v . arrow pointing down + <STRONG>ACS_DEGREE</STRONG> ' f degree symbol + <STRONG>ACS_DIAMOND</STRONG> + ` diamond + <STRONG>ACS_GEQUAL</STRONG> > > greater-than-or-equal-to + <STRONG>ACS_HLINE</STRONG> - q horizontal line + <STRONG>ACS_LANTERN</STRONG> # i lantern symbol + <STRONG>ACS_LARROW</STRONG> < , arrow pointing left + <STRONG>ACS_LEQUAL</STRONG> < y less-than-or-equal-to + <STRONG>ACS_LLCORNER</STRONG> + m lower left-hand corner + <STRONG>ACS_LRCORNER</STRONG> + j lower right-hand corner + <STRONG>ACS_LTEE</STRONG> + t left tee + <STRONG>ACS_NEQUAL</STRONG> ! | not-equal + <STRONG>ACS_PI</STRONG> * { greek pi + <STRONG>ACS_PLMINUS</STRONG> # g plus/minus + <STRONG>ACS_PLUS</STRONG> + n plus + <STRONG>ACS_RARROW</STRONG> > + arrow pointing right + <STRONG>ACS_RTEE</STRONG> + u right tee + <STRONG>ACS_S1</STRONG> - o scan line 1 + <STRONG>ACS_S3</STRONG> - p scan line 3 + <STRONG>ACS_S7</STRONG> - r scan line 7 + <STRONG>ACS_S9</STRONG> _ s scan line 9 + <STRONG>ACS_STERLING</STRONG> f } pound-sterling symbol + <STRONG>ACS_TTEE</STRONG> + w top tee + <STRONG>ACS_UARROW</STRONG> ^ - arrow pointing up + <STRONG>ACS_ULCORNER</STRONG> + l upper left-hand corner + <STRONG>ACS_URCORNER</STRONG> + k upper right-hand corner + <STRONG>ACS_VLINE</STRONG> | x vertical line </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE> - All routines return the integer <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> on success (the - SVr4 manuals specify only "an integer value other than <STRONG>ERR</STRONG>") upon - successful completion, unless otherwise noted in the preceding routine - descriptions. + These functions return <STRONG>OK</STRONG> on success and <STRONG>ERR</STRONG> on failure. - Functions with a "mv" prefix first perform a cursor movement using - <STRONG>wmove</STRONG>, and return an error if the position is outside the window, or if - the window pointer is null. + In <EM>ncurses</EM>, <STRONG>waddch</STRONG> returns <STRONG>ERR</STRONG> if it is not possible to add a complete + character at the cursor position, as when conversion of a multibyte + character to a byte sequence fails, or at least one of the resulting + bytes cannot be added to the window. See section "PORTABILITY" below + regarding the use of <STRONG>waddch</STRONG> with multibyte characters. - If it is not possible to add a complete character, an error is - returned: + <STRONG>waddch</STRONG> can successfully write a character at the bottom right location + of the window. However, <EM>ncurses</EM> returns <STRONG>ERR</STRONG> if <STRONG><A HREF="scrollok.3x.html">scrollok(3x)</A></STRONG> is not + enabled in that event, because it is not possible to wrap to a new + line. - <STRONG>o</STRONG> If <STRONG>scrollok</STRONG> is not enabled, writing a character at the lower right - margin succeeds. However, an error is returned because it is not - possible to wrap to a new line - - <STRONG>o</STRONG> If an error is detected when converting a multibyte character to a - sequence of bytes, or if it is not possible to add all of the - resulting bytes in the window, an error is returned. + Functions prefixed with "mv" first perform cursor movement and fail if + the position (<EM>y</EM>, <EM>x</EM>) is outside the window boundaries. </PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE> - Note that <STRONG>addch</STRONG>, <STRONG>mvaddch</STRONG>, <STRONG>mvwaddch</STRONG>, and <STRONG>echochar</STRONG> may be macros. + <STRONG>addch</STRONG>, <STRONG>mvaddch</STRONG>, <STRONG>mvwaddch</STRONG>, and <STRONG>echochar</STRONG> may be implemented as macros. </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE> - All these functions are described in the XSI Curses standard, Issue 4. - The defaults specified for forms-drawing characters apply in the POSIX + X/Open Curses, Issue 4 describes these functions. It specifies no + error conditions for them. + + SVr4 <EM>curses</EM> describes a successful return value only as "an integer + value other than <STRONG>ERR</STRONG>". + + The defaults specified for forms-drawing characters apply in the POSIX locale. </PRE><H3><a name="h3-ACS-Symbols">ACS Symbols</a></H3><PRE> - X/Open Curses states that the <EM>ACS</EM><STRONG>_</STRONG> definitions are <STRONG>char</STRONG> constants. For - the wide-character implementation (see <STRONG>curs_add_wch</STRONG>), there are - analogous <EM>WACS</EM><STRONG>_</STRONG> definitions which are <STRONG>cchar_t</STRONG> constants. Some - implementations are problematic: + X/Open Curses states that the <STRONG>ACS_</STRONG> definitions are <EM>char</EM> constants. + + Some implementations are problematic. - <STRONG>o</STRONG> Some implementations define the ACS symbols to a constant (such as - Solaris), while others define those to entries in an array. + <STRONG>o</STRONG> Solaris <EM>curses</EM>, for example, define the ACS symbols as constants; + others define them as elements of an array. - This implementation uses an array <STRONG>acs_map</STRONG>, as done in SVr4 curses. + This implementation uses an array, <STRONG>acs_map</STRONG>, as did SVr4 <EM>curses</EM>. NetBSD also uses an array, actually named <STRONG>_acs_char</STRONG>, with a <STRONG>#define</STRONG> for compatibility. - <STRONG>o</STRONG> HPUX curses equates some of the <EM>ACS</EM><STRONG>_</STRONG> symbols to the analogous <EM>WACS</EM><STRONG>_</STRONG> - symbols as if the <EM>ACS</EM><STRONG>_</STRONG> symbols were wide characters. The - misdefined symbols are the arrows and other symbols which are not - used for line-drawing. + <STRONG>o</STRONG> HP-UX <EM>curses</EM> equates some of the <STRONG>ACS_</STRONG> symbols to the analogous + <STRONG>WACS_</STRONG> symbols as if the <STRONG>ACS_</STRONG> symbols were wide characters (see + <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>). The misdefined symbols are the arrows and + others that are not used for line drawing. - <STRONG>o</STRONG> X/Open Curses (issues 2 through 7) has a typographical error for - the ACS_LANTERN symbol, equating its "VT100+ Character" to <STRONG>I</STRONG> - (capital I), while the header files for SVr4 curses and the various - implementations use <STRONG>i</STRONG> (lowercase). + <STRONG>o</STRONG> X/Open Curses (Issues 2 through 7) has a typographical error for + the <STRONG>ACS_LANTERN</STRONG> symbol, equating its "VT100+ Character" to "I" + (capital I), while the header files for SVr4 <EM>curses</EM> and other + implementations use "i" (small i). - None of the terminal descriptions on Unix platforms use uppercase- - I, except for Solaris (i.e., <EM>screen</EM>'s terminal description, + None of the terminal descriptions on Unix platforms use uppercase + I, except for Solaris (in its <EM>terminfo</EM> entry for <STRONG>screen(1)</STRONG>, apparently based on the X/Open documentation around 1995). On the - other hand, the terminal description <EM>gs6300</EM> (AT&T PC6300 with EMOTS - Terminal Emulator) uses lowercase-i. + other hand, its <STRONG>gs6300</STRONG> (AT&T PC6300 with EMOTS Terminal Emulator) + description uses lowercase i. - Some ACS symbols (ACS_S3, ACS_S7, ACS_LEQUAL, ACS_GEQUAL, ACS_PI, - ACS_NEQUAL, ACS_STERLING) were not documented in any publicly released - System V. However, many publicly available terminfos include <STRONG>acsc</STRONG> - strings in which their key characters (pryz{|}) are embedded, and a - second-hand list of their character descriptions has come to light. - The ACS-prefixed names for them were invented for <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>. + Some ACS symbols (<STRONG>ACS_S3</STRONG>, <STRONG>ACS_S7</STRONG>, <STRONG>ACS_LEQUAL</STRONG>, <STRONG>ACS_GEQUAL</STRONG>, <STRONG>ACS_PI</STRONG>, + <STRONG>ACS_NEQUAL</STRONG>, and <STRONG>ACS_STERLING</STRONG>) were not documented in any publicly + released System V. However, many publicly available <EM>terminfo</EM> entries + include <STRONG>acsc</STRONG> strings in which their key characters <STRONG>(</STRONG>pryz{|}<STRONG>)</STRONG> are + embedded, and a second-hand list of their character descriptions has + come to light. The <EM>ncurses</EM> developers invented ACS-prefixed names for + them. - The <EM>displayed</EM> values for the <EM>ACS</EM><STRONG>_</STRONG> and <EM>WACS</EM><STRONG>_</STRONG> constants depend on + The <EM>displayed</EM> values of <STRONG>ACS_</STRONG> constants depend on - <STRONG>o</STRONG> the library configuration, i.e., <STRONG>ncurses</STRONG> versus <STRONG>ncursesw</STRONG>, where the - latter is capable of displaying Unicode while the former is not, - and + <STRONG>o</STRONG> the <EM>ncurses</EM> ABI--for example, wide-character versus non-wide- + character configurations (the former is capable of displaying + Unicode while the latter is not), and - <STRONG>o</STRONG> whether the <EM>locale</EM> uses UTF-8 encoding. + <STRONG>o</STRONG> whether the locale uses UTF-8 encoding. - In certain cases, the terminal is unable to display line-drawing - characters except by using UTF-8 (see the discussion of - <STRONG>NCURSES_NO_UTF8_ACS</STRONG> in <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>). + In certain cases, the terminal is unable to display forms-drawing + characters <EM>except</EM> by using UTF-8; see the discussion of the + <EM>NCURSES</EM><STRONG>_</STRONG><EM>NO</EM><STRONG>_</STRONG><EM>UTF8</EM><STRONG>_</STRONG><EM>ACS</EM> environment variable in <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG>). </PRE><H3><a name="h3-Character-Set">Character Set</a></H3><PRE> - X/Open Curses assumes that the parameter passed to <STRONG>waddch</STRONG> contains a - single character. As discussed in <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>, that character may - have been more than eight bits in an SVr3 or SVr4 implementation, but - in the X/Open Curses model, the details are not given. The important - distinction between SVr4 curses and X/Open Curses is that the non- - character information (attributes and color) was separated from the - character information which is packed in a <STRONG>chtype</STRONG> to pass to <STRONG>waddch</STRONG>. - - In this implementation, <STRONG>chtype</STRONG> holds an eight-bit character. But - ncurses allows multibyte characters to be passed in a succession of - calls to <STRONG>waddch</STRONG>. The other implementations do not do this; a call to - <STRONG>waddch</STRONG> passes exactly one character which may be rendered as one or - more cells on the screen depending on whether it is printable. - - Depending on the locale settings, ncurses will inspect the byte passed - in each call to <STRONG>waddch</STRONG>, and check if the latest call will continue a - multibyte sequence. When a character is <EM>complete</EM>, ncurses displays the - character and moves to the next position in the screen. + X/Open Curses assumes that the parameter passed to <STRONG>waddch</STRONG> contains a + single character. As discussed in <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>, that character may + have been more than eight bits wide in an SVr3 or SVr4 implementation, + but in the X/Open Curses model, the details are not given. The + important distinction between SVr4 <EM>curses</EM> and X/Open Curses is that the + latter separates non-character information (attributes and color) from + the character code, which SVr4 packs into a <EM>chtype</EM> for passage to + <STRONG>waddch</STRONG>. + + In <EM>ncurses</EM>, <EM>chtype</EM> holds an eight-bit character. But the library + allows a multibyte character to be passed in a succession of calls to + <STRONG>waddch</STRONG>. Other implementations do not; a <STRONG>waddch</STRONG> call transmits exactly + one character, which may be rendered in one or more screen locations + depending on whether it is printable. + + Depending on the locale settings, <EM>ncurses</EM> inspects the byte passed in + each <STRONG>waddch</STRONG> call, and checks whether the latest call continues a + multibyte sequence. When a character is <EM>complete</EM>, <EM>ncurses</EM> displays the + character and advances the cursor. If the calling application interrupts the succession of bytes in a - multibyte character by moving the current location (e.g., using <STRONG>wmove</STRONG>), - ncurses discards the partially built character, starting over again. + multibyte character sequence by changing the current location--for + example, with <STRONG><A HREF="curs_move.3x.html">wmove(3x)</A></STRONG>--<EM>ncurses</EM> discards the incomplete character. For portability to other implementations, do not rely upon this - behavior: + behavior. Check whether a character can be represented as a single + byte in the current locale. - <STRONG>o</STRONG> check if a character can be represented as a single byte in the - current locale before attempting call <STRONG>waddch</STRONG>, and + <STRONG>o</STRONG> If it can, call either <STRONG>waddch</STRONG> or <STRONG><A HREF="curs_add_wch.3x.html">wadd_wch(3x)</A></STRONG>. - <STRONG>o</STRONG> call <STRONG>wadd_wch</STRONG> for characters which cannot be handled by <STRONG>waddch</STRONG>. + <STRONG>o</STRONG> If it cannot, use only <STRONG><A HREF="curs_add_wch.3x.html">wadd_wch(3x)</A></STRONG>. </PRE><H3><a name="h3-TABSIZE">TABSIZE</a></H3><PRE> - The <STRONG>TABSIZE</STRONG> variable is implemented in SVr4 and other versions of - curses, but is not part of X/Open curses (see <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG> for - more details). - - If <EM>ch</EM> is a carriage return, the cursor is moved to the beginning of the - current row of the window. This is true of other implementations, but - is not documented. + SVr4 and other versions of <EM>curses</EM> implement the <STRONG>TABSIZE</STRONG> variable, but + X/Open Curses does not specify it (see <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>). </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE> - <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>, <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>, <STRONG><A HREF="curs_inch.3x.html">curs_inch(3x)</A></STRONG>, - <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>, <STRONG>putc(3)</STRONG>. + <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG> describes comparable functions of the <EM>ncurses</EM> library + in its wide-character configuration (<EM>ncursesw</EM>). - Comparable functions in the wide-character (ncursesw) library are - described in <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>. + <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_addchstr.3x.html">curs_addchstr(3x)</A></STRONG>, <STRONG><A HREF="curs_addstr.3x.html">curs_addstr(3x)</A></STRONG>, <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>, + <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>, <STRONG><A HREF="curs_inch.3x.html">curs_inch(3x)</A></STRONG>, <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>, + <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>, <STRONG>putchar(3)</STRONG> - <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG> +ncurses 6.5 2024-04-20 <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG> </PRE> <div class="nav"> <ul> @@ -306,9 +308,9 @@ <li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li> <li><a href="#h2-DESCRIPTION">DESCRIPTION</a> <ul> -<li><a href="#h3-Adding-characters">Adding characters</a></li> -<li><a href="#h3-Echoing-characters">Echoing characters</a></li> -<li><a href="#h3-Line-Graphics">Line Graphics</a></li> +<li><a href="#h3-Adding-Characters">Adding Characters</a></li> +<li><a href="#h3-Echoing-Characters">Echoing Characters</a></li> +<li><a href="#h3-Forms-Drawing-Characters">Forms-Drawing Characters</a></li> </ul> </li> <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li> |