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<H1 class="no-header">curs_addch 3x 2025-11-11 ncurses 6.6 Library calls</H1>
<PRE>
<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 <EM>curses</EM>
character to a window and advance the cursor
</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
<STRONG>int</STRONG> <STRONG>addch(const</STRONG> <STRONG>chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>waddch(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>mvaddch(int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>mvwaddch(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>echochar(const</STRONG> <STRONG>chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>wechochar(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG>
<EM>/*</EM> <EM>(integer)</EM> <EM>constants</EM> <EM>*/</EM>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_BLOCK;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_BOARD;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_BTEE;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_BULLET;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_CKBOARD;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_DARROW;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_DEGREE;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_DIAMOND;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_HLINE;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_LANTERN;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_LARROW;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_LLCORNER;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_LRCORNER;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_LTEE;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_PLMINUS;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_PLUS;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_RARROW;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_RTEE;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_S1;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_S9;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_TTEE;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_UARROW;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_ULCORNER;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_URCORNER;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_VLINE;</STRONG>
<EM>/*</EM> <EM>extensions</EM> <EM>*/</EM>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_GEQUAL;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_LEQUAL;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_NEQUAL;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_PI;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_S3;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_S7;</STRONG>
/* <EM>...</EM> <EM>*/</EM> <STRONG>ACS_STERLING;</STRONG>
</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
</PRE><H3><a name="h3-waddch">waddch</a></H3><PRE>
<STRONG>waddch</STRONG> writes the <EM>curses</EM> character <EM>ch</EM> to the 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.
Construct a <EM>curses</EM> character from a <EM>char</EM> by assignment or typecast.
Subsection "Video Attributes" of <STRONG><A HREF="curs_attr.3x.html">attron(3x)</A></STRONG> describes how to manipulate
its attributes and color pair. (A color pair selection is not honored
unless initialized; see <STRONG><A HREF="curs_color.3x.html">start_color(3x)</A></STRONG>.)
The object or expression <EM>ch</EM> may contain attributes and/or a color pair
identifier. (A <EM>chtype</EM> can be copied from place to place using
<STRONG><A HREF="curs_inch.3x.html">winch(3x)</A></STRONG> and <STRONG>waddch</STRONG>.) <EM>curses</EM> defines constants to aid the
manipulation of character attributes; see <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>. A <EM>ch</EM> whose
character component is a space, and whose only attribute is <STRONG>A_NORMAL</STRONG>,
is a <EM>blank</EM> <EM>character</EM>, and therefore combines with the window's
background character; see <STRONG><A HREF="curs_bkgd.3x.html">curs_bkgd(3x)</A></STRONG>.
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 margin
of a window, it does nothing.
<STRONG>o</STRONG> Carriage return moves the cursor to the left margin on the same
line of the window.
<STRONG>o</STRONG> Line feed does a <STRONG><A HREF="curs_clear.3x.html">clrtoeol(3x)</A></STRONG>, then advances as if from the right
margin.
<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, <EM>curses</EM> draws it in printable
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.
Adding printable characters with <STRONG>waddch</STRONG> causes it to wrap at the right
margin of the window:
<STRONG>o</STRONG> If the cursor is not at the bottom of the scrolling region and
advancement occurs at the right margin, the cursor automatically
wraps to the beginning of the next line.
<STRONG>o</STRONG> If the cursor is at the bottom of the scrolling region when
advancement occurs at the right margin, and <STRONG><A HREF="scrollok.3x.html">scrollok(3x)</A></STRONG> is enabled
for <EM>win</EM>, the scrolling region scrolls up one line and the cursor
wraps as above. Otherwise, advancement and scrolling do not occur,
and <STRONG>waddch</STRONG> returns <STRONG>ERR</STRONG>.
A window's margins may coincide with the screen boundaries. This may
be a problem when <EM>ncurses</EM> updates the screen to match the curses
window. When their right and bottom margins coincide, <EM>ncurses</EM> uses
different strategies to handle the variations of scrolling and wrapping
at the lower-right corner by depending on the terminal capabilities:
<STRONG>o</STRONG> If the terminal does not automatically wrap as characters are added
at the right margin (i.e., auto right margins), <EM>ncurses</EM> writes the
character directly.
<STRONG>o</STRONG> If the terminal has auto right margins, but also has capabilities
for turning auto margins off and on, <EM>ncurses</EM> turns the auto margin
feature off temporarily when writing to the lower-right corner.
<STRONG>o</STRONG> If the terminal has an insertion mode which can be turned off and
on, <EM>ncurses</EM> writes the character just before the lower-right
corner, and then inserts a character to push the update into the
corner.
</PRE><H3><a name="h3-wechochar">wechochar</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> on <STRONG>stdscr</STRONG> or the specified window. <EM>curses</EM> interprets these
functions as a hint to its optimizer that only a single character cell
in the window is being altered between refreshes; 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 symbols to the screen. <EM>ncurses</EM> terms
these <EM>forms-drawing</EM> <EM>characters.</EM> <EM>curses</EM> uses the ACS default listed
below if the terminal type lacks the <STRONG>acs_chars</STRONG> (<STRONG>acsc</STRONG>) capability; that
capability does not define a replacement for the character; or if the
terminal type and locale configuration require 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>
(<STRONG>acsc</STRONG>) 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.
<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>
These functions return <STRONG>OK</STRONG> on success and <STRONG>ERR</STRONG> on failure.
In <EM>ncurses</EM>, these functions fail if
<STRONG>o</STRONG> the <EM>curses</EM> screen has not been initialized,
<STRONG>o</STRONG> (for functions taking a <EM>WINDOW</EM> pointer argument) <EM>win</EM> is a null
pointer,
<STRONG>o</STRONG> wrapping to a new line is impossible because <STRONG><A HREF="scrollok.3x.html">scrollok(3x)</A></STRONG> has not
been called on <EM>win</EM> (or <STRONG>stdscr</STRONG>, as applicable) when a write to its
bottom right location is attempted, or
<STRONG>o</STRONG> it is not possible to add a complete character at the cursor
position.
The last may be due to different causes:
<STRONG>o</STRONG> conversion of a wide character to a multibyte character sequence
can fail, or
<STRONG>o</STRONG> at least one of the bytes resulting from wide character conversion
to a multibyte character sequence cannot be added to the window.
See section "PORTABILITY" below regarding the use of <STRONG>waddch</STRONG> with
wide characters.
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>
<STRONG>addch</STRONG>, <STRONG>mvaddch</STRONG>, <STRONG>mvwaddch</STRONG>, and <STRONG>echochar</STRONG> may be implemented as macros.
</PRE><H2><a name="h2-EXTENSIONS">EXTENSIONS</a></H2><PRE>
The symbols <EM>ACS</EM><STRONG>_</STRONG><EM>S3</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>S7</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>LEQUAL</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>GEQUAL</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>PI</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>NEQUAL</EM>,
and <EM>ACS</EM><STRONG>_</STRONG><EM>STERLING</EM> were not documented in any publicly released System V
and are not standard. However, many publicly available <EM>terminfo</EM>
entries include <STRONG>acs_chars</STRONG> (<STRONG>acsc</STRONG>) capabilities in which their key
characters (<STRONG>pryz{|}</STRONG>) are embedded, and a second-hand list of their
character descriptions has come to light, which identifies them as
VT100 special characters.
The DEC Special Character and Line Drawing Set (VT100) is indexed by an
ASCII character in the range 96 (`) to 126 (~). That index character
is part of the definition for the curses <STRONG>ACS_</STRONG> symbols. The VT100
special characters can be categorized in three groups:
<STRONG>o</STRONG> useful graphic symbols with a standard <STRONG>ACS_</STRONG> symbol, (e.g., the
line-drawing symbols),
<STRONG>o</STRONG> possibly useful characters (these non-standard symbols),
<STRONG>o</STRONG> representations of control characters (e.g., newline and vertical
tabulation).
A few <STRONG>ACS_</STRONG> symbols do not fit into DEC's VT100 scheme. The AT&T
Teletype 5410v1 arrow symbols and <STRONG>ACS_BLOCK</STRONG> use indices outside the
range 96 to 126. Two of the Teletype symbols use indices in that
range, with different meaning versus the VT100:
<STRONG>o</STRONG> <STRONG>ACS_BOARD</STRONG> corresponds to the VT100 symbol for newline
<STRONG>o</STRONG> <STRONG>ACS_LANTERN</STRONG> corresponds to the VT100 symbol for vertical tabulation
AT&T defined <STRONG>ACS_</STRONG> names for the most useful graphic symbols, as well as
for its own. Its header file commented:
/*
* Standard alternate character set. The current ACS world is
* evolving, so we support only a widely available subset: the
* line drawing characters from the VT100, plus a few from the
* Teletype 5410v1. Eventually there may be support of more
* sophisticated ACS line drawing, such as that in the Teletype
* 5410, the HP line drawing set, and the like. There may be
* support for some non line oriented characters as well.
*
* Line drawing ACS names are of the form ACS_trbl, where t is
* the top, r is the right, b is the bottom, and l is the left.
* t, r, b, and l might be B (blank), S (single), D (double), or
* T (thick). The subset defined here only uses B and S.
*/
Although these less-useful graphic symbols were not given names, they
were used in <EM>terminfo</EM> entries. The <EM>ncurses</EM> developers invented ACS-
prefixed names for them.
</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
Applications employing <EM>ncurses</EM> extensions should condition their use on
the visibility of the <STRONG>NCURSES_VERSION</STRONG> preprocessor macro.
X/Open Curses Issue 4 describes these functions. It specifies no error
conditions for them.
SVr4 describes a successful return value only as "an integer value
other than <EM>ERR</EM>".
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 <EM>char</EM> constants.
Some implementations are problematic.
<STRONG>o</STRONG> Solaris <EM>curses</EM>, for example, defines the ACS symbols as constants;
others define them as elements of an array.
SVr4 used an array, <EM>acs</EM><STRONG>_</STRONG><EM>map</EM>, as does <EM>ncurses</EM>. NetBSD <EM>curses</EM> also
uses an array, actually named <STRONG>_</STRONG><EM>acs</EM><STRONG>_</STRONG><EM>char</EM>, with a "#define" for
compatibility.
<STRONG>o</STRONG> HP-UX <EM>curses</EM> 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 (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 <EM>ACS</EM><STRONG>_</STRONG><EM>LANTERN</EM> 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 (in its <EM>terminfo</EM> entry for <STRONG>screen(1)</STRONG>,
apparently based on the X/Open documentation around 1995). On the
other hand, its <STRONG>gs6300</STRONG> (AT&T PC6300 with EMOTS Terminal Emulator)
description uses lowercase i.
The <EM>displayed</EM> values of <EM>ACS</EM><STRONG>_</STRONG> constants depend on
<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 locale uses UTF-8 encoding.
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 <EM>waddch</EM> contains a
single character. That character may have been more than eight bits
wide in an SVr3 or SVr4 implementation, but X/Open Curses leaves the
width of a non-wide character code unspecified. The standard further
does not specify the internal structure of a <EM>chtype</EM>, though the use of
bitwise operators to combine the character code with attributes and a
color pair identifier into a <EM>chtype</EM> for passage to <EM>waddch</EM> is common. A
portable application uses only the macros discussed in <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG> to
manipulate a <EM>chtype</EM>.
In <EM>ncurses</EM>, <EM>chtype</EM> holds an eight-bit character, but the library allows
a multibyte character sequence to be passed via a succession of calls
to <EM>waddch</EM>. Other implementations do not; a <EM>waddch</EM> call transmits
exactly one character, which may be rendered in one or more screen
locations depending on whether it is printable (see <STRONG><A HREF="unctrl.3x.html">unctrl(3x)</A></STRONG>).
Depending on the locale, <EM>ncurses</EM> inspects the byte passed in each
<EM>waddch</EM> call and checks whether the latest call continues a multibyte
character. 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 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 the
foregoing behavior. Check whether a character can be represented as a
single byte in the current locale.
<STRONG>o</STRONG> If it can, call either <EM>waddch</EM> or <EM>wadd</EM><STRONG>_</STRONG><EM>wch</EM>.
<STRONG>o</STRONG> If it cannot, use only <EM>wadd</EM><STRONG>_</STRONG><EM>wch</EM>.
</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE>
4BSD (1980) introduced <EM>waddch</EM> and its variants.
SVr3 (1987) added the <EM>echochar</EM> and <EM>wechochar</EM> functions and most of the
<EM>ACS</EM><STRONG>_</STRONG> constants, except for <EM>ACS</EM><STRONG>_</STRONG><EM>GEQUAL</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>LEQUAL</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>NEQUAL</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>PI</EM>,
<EM>ACS</EM><STRONG>_</STRONG><EM>S3</EM>, <EM>ACS</EM><STRONG>_</STRONG><EM>S7</EM>, and <EM>ACS</EM><STRONG>_</STRONG><EM>STERLING</EM>.
<EM>ncurses</EM> 1.9.6 (1995) furnished the remaining <EM>ACS</EM><STRONG>_</STRONG> constants.
</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
<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>).
<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_bkgd.3x.html">curs_bkgd(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>
ncurses 6.6 2025-11-11 <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
<li><a href="#h3-waddch">waddch</a></li>
<li><a href="#h3-wechochar">wechochar</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>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-EXTENSIONS">EXTENSIONS</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a>
<ul>
<li><a href="#h3-ACS-Symbols">ACS Symbols</a></li>
<li><a href="#h3-Character-Set">Character Set</a></li>
</ul>
</li>
<li><a href="#h2-HISTORY">HISTORY</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
</ul>
</div>
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