1curs_addch(3X) curs_addch(3X)
2
6 addch, waddch, mvaddch, mvwaddch, echochar, wechochar - add a character
7 (with attributes) to a curses window, then advance the cursor
8
10 #include <curses.h>
11 int addch(const chtype ch);
13 int waddch(WINDOW *win, const chtype ch);
14 int mvaddch(int y, int x, const chtype ch);
15 int mvwaddch(WINDOW *win, int y, int x, const chtype ch);
16 int echochar(const chtype ch);
17 int wechochar(WINDOW *win, const chtype ch);
18
20 The addch, waddch, mvaddch and mvwaddch routines put the character ch
21 into the given window at its current window position, which is then
22 advanced. They are analogous to putchar in stdio(3). If the advance
23 is at the right margin, the cursor automatically wraps to the beginning
24 of the next line. At the bottom of the current scrolling region, if
25 scrollok is enabled, the scrolling region is scrolled up one line.
26 If ch is a tab, newline, or backspace, the cursor is moved appropri‐
28 ately within the window. Backspace moves the cursor one character
29 left; at the left edge of a window it does nothing. Newline does a
30 clrtoeol, then moves the cursor to the window left margin on the next
31 line, scrolling the window if on the last line. Tabs are considered to
32 be at every eighth column. The tab interval may be altered by setting
33 the TABSIZE variable.
34 If ch is any control character other than tab, newline, or backspace,
36 it is drawn in ^X notation. Calling winch after adding a control char‐
37 acter does not return the character itself, but instead returns the
38 ^-representation of the control character.
39 Video attributes can be combined with a character argument passed to
41 addch or related functions by logical-ORing them into the character.
42 (Thus, text, including attributes, can be copied from one place to
43 another using inch and addch.) See the curs_attr(3X) page for values
44 of predefined video attribute constants that can be usefully OR'ed into
45 characters.
46 The echochar and wechochar routines are equivalent to a call to addch
48 followed by a call to refresh, or a call to waddch followed by a call
49 to wrefresh. The knowledge that only a single character is being out‐
50 put is used and, for non-control characters, a considerable performance
51 gain may be seen by using these routines instead of their equivalents.
52 Line Graphics
54 The following variables may be used to add line drawing characters to
55 the screen with routines of the addch family. The default character
56 listed below is used if the acsc capability does not define a terminal-
57 specific replacement for it. The names are taken from VT100 nomencla‐
58 ture.
59 Name Default Description
61 ──────────────────────────────────────────────────
62 ACS_BLOCK # solid square block
63 ACS_BOARD # board of squares
64 ACS_BTEE + bottom tee
65 ACS_BULLET o bullet
66 ACS_CKBOARD : checker board (stipple)
68 ACS_DARROW v arrow pointing down
69 ACS_DEGREE ' degree symbol
70 ACS_DIAMOND + diamond
71 ACS_GEQUAL > greater-than-or-equal-to
72 ACS_HLINE - horizontal line
73 ACS_LANTERN # lantern symbol
74 ACS_LARROW < arrow pointing left
75 ACS_LEQUAL < less-than-or-equal-to
76 ACS_LLCORNER + lower left-hand corner
77 ACS_LRCORNER + lower right-hand corner
78 ACS_LTEE + left tee
79 ACS_NEQUAL ! not-equal
80 ACS_PI * greek pi
81 ACS_PLMINUS # plus/minus
82 ACS_PLUS + plus
83 ACS_RARROW > arrow pointing right
84 ACS_RTEE + right tee
85 ACS_S1 - scan line 1
86 ACS_S3 - scan line 3
87 ACS_S7 - scan line 7
88 ACS_S9 _ scan line 9
89 ACS_STERLING f pound-sterling symbol
90 ACS_TTEE + top tee
91 ACS_UARROW ^ arrow pointing up
92 ACS_ULCORNER + upper left-hand corner
93 ACS_URCORNER + upper right-hand corner
94 ACS_VLINE | vertical line
95
97 All routines return the integer ERR upon failure and OK on success (the
98 SVr4 manuals specify only "an integer value other than ERR") upon suc‐
99 cessful completion, unless otherwise noted in the preceding routine
100 descriptions.
101 Functions with a "mv" prefix first perform a cursor movement using
103 wmove, and return an error if the position is outside the window, or if
104 the window pointer is null.
105
107 Note that addch, mvaddch, mvwaddch, and echochar may be macros.
108
110 All these functions are described in the XSI Curses standard, Issue 4.
111 The defaults specified for forms-drawing characters apply in the POSIX
112 locale.
113 X/Open Curses states that the ACS_ definitions are char constants. For
115 the wide-character implementation (see curs_add_wch), there are analo‐
116 gous WACS_ definitions which are cchar_t constants.
117 Some ACS symbols (ACS_S3, ACS_S7, ACS_LEQUAL, ACS_GEQUAL, ACS_PI,
119 ACS_NEQUAL, ACS_STERLING) were not documented in any publicly released
120 System V. However, many publicly available terminfos include acsc
121 strings in which their key characters (pryz{|}) are embedded, and a
122 second-hand list of their character descriptions has come to light.
123 The ACS-prefixed names for them were invented for ncurses(3X).
124 The TABSIZE variable is implemented in some versions of curses, but is
126 not part of X/Open curses.
127 If ch is a carriage return, the cursor is moved to the beginning of the
129 current row of the window. This is true of other implementations, but
130 is not documented.
131
133 curses(3X), curs_attr(3X), curs_clear(3X), curs_inch(3X), curs_out‐
134 opts(3X), curs_refresh(3X), curs_variables(3X), putc(3).
135 Comparable functions in the wide-character (ncursesw) library are
137 described in curs_add_wch(3X).
138 curs_addch(3X)