The addch, waddch, mvaddch and mvwaddch routines put the
character ch into the given window at its current window
position, which is then advanced. They are analogous to
@@ -85,25 +84,27 @@
returned because it is not possible to wrap to a new
line
- If ch is a tab, newline, or backspace, the cursor is moved
- appropriately within the window:
+ If ch is a tab, newline, carriage return or backspace, the
+ cursor is moved appropriately within the window:
o Backspace moves the cursor one character left; at the
left edge of a window it does nothing.
- o Newline does a clrtoeol, then moves the cursor to the
- window left margin on the next line, scrolling the
+ o Carriage return moves the cursor to the window left
+ margin on the current line.
+
+ o Newline does a clrtoeol, then moves the cursor to the
+ window left margin on the next line, scrolling the
window if on the last line.
o Tabs are considered to be at every eighth column. The
- tab interval may be altered by setting the TABSIZE
+ tab interval may be altered by setting the TABSIZE
variable.
- If ch is any control character other than tab, newline, or
- backspace, it is drawn in ^X notation. Calling winch
- after adding a control character does not return the char-
- acter itself, but instead returns the ^-representation of
- the control character.
+ If ch is any other control character, it is drawn in ^X
+ notation. Calling winch after adding a control character
+ does not return the character itself, but instead returns
+ the ^-representation of the control character.
Video attributes can be combined with a character argument
passed to addch or related functions by logical-ORing them
@@ -113,6 +114,8 @@
fined video attribute constants that can be usefully OR'ed
into characters.
+
+
The echochar and wechochar routines are equivalent to a
call to addch followed by a call to refresh, or a call to
waddch followed by a call to wrefresh. The knowledge that
@@ -121,13 +124,17 @@
may be seen by using these routines instead of their
equivalents.
- LineGraphics
+
+
The following variables may be used to add line drawing
characters to the screen with routines of the addch fam-
ily. The default character listed below is used if the
acsc capability does not define a terminal-specific
- replacement for it. The names are taken from VT100 nomen-
- clature.
+ replacement for it, or if the terminal and locale configu-
+ ration requires Unicode but the library is unable to use
+ Unicode.
+
+ The names are taken from VT100 nomenclature.
NameDefaultDescription
--------------------------------------------------
@@ -165,44 +172,54 @@
ACS_VLINE | vertical line
-
All routines return the integer ERR upon failure and OK on
- success (the SVr4 manuals specify only "an integer value
+ success (the SVr4 manuals specify only "an integer value
other than ERR") upon successful completion, unless other-
wise noted in the preceding routine descriptions.
- Functions with a "mv" prefix first perform a cursor move-
- ment using wmove, and return an error if the position is
+ Functions with a "mv" prefix first perform a cursor move-
+ ment using wmove, and return an error if the position is
outside the window, or if the window pointer is null.
-
-
NOTES
- Note that addch, mvaddch, mvwaddch, and echochar may be
+
+ All these functions are described in the XSI Curses stan-
+ dard, Issue 4. The defaults specified for forms-drawing
characters apply in the POSIX locale.
- X/Open Curses states that the ACS_ definitions are char
- constants. For the wide-character implementation (see
+ X/Open Curses states that the ACS_ definitions are char
+ constants. For the wide-character implementation (see
curs_add_wch), there are analogous WACS_ definitions which
are cchar_t constants.
- 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 acsc 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
+ 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 acsc 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
ncurses(3x).
+ The displayed values for the ACS_ and WACS_ constants
+ depend on
+
+ o the library configuration, i.e., ncurses versus ncurs-
+ esw, where the latter is capable of displaying Unicode
+ while the former is not, and
+
+ o 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 discus-
+ sion of NCURSES_NO_UTF8_ACS in ncurses(3x)).
+
The TABSIZE variable is implemented in some versions of
curses, but is not part of X/Open curses.
@@ -211,8 +228,7 @@
of other implementations, but is not documented.
-