wechochar - Cheap VPS LLC

curs_addch


Section: Miscellaneous Library Functions (3X)
Updated:
Index
Return to Main Contents

 

NAME

addch, waddch, mvaddch, mvwaddch,
echochar,
wechochar – add a character (with attributes) to a curses window, then advance the cursor
 

SYNOPSIS

#include <curses.h>

int addch(const chtype ch);

int waddch(WINDOW *win, const chtype ch);

int mvaddch(int y, int x, const chtype ch);

int mvwaddch(WINDOW *win, int y, int x, const chtype ch);

int echochar(const chtype ch);

int wechochar(WINDOW *win, const chtype ch);

 

DESCRIPTION

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 putchar in stdio(3).
If the advance is at the right margin, the cursor automatically wraps to the
beginning of the next line. At the bottom of the current scrolling region, if
scrollok is enabled, the scrolling region is scrolled up one line.

If ch is a tab, newline, or backspace,
the cursor is moved appropriately within the window.
Backspace moves the cursor one character left; at the left
edge of a window it does nothing.
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.
Tabs are considered to be at every eighth column.
The 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 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 into the character.
(Thus, text, including attributes, can be copied from one place to another
using inch and addch.) See the curs_attr(3X) page for
values of predefined 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 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.
 

Line Graphics

The following variables may be used to add line drawing characters to the
screen with routines of the addch family. 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 nomenclature.



































NameDefaultDescription



ACS_BOARD#board of squares
ACS_BTEE+bottom tee
ACS_BULLETobullet
ACS_CKBOARD:checker board (stipple)
ACS_DARROWvarrow pointing down
ACS_DEGREEdegree symbol
ACS_DIAMOND+diamond
ACS_GEQUAL>greater-than-or-equal-to
ACS_HLINE-horizontal line
ACS_LANTERN#lantern symbol
ACS_LARROW<arrow pointing left
ACS_LEQUAL<less-than-or-equal-to
ACS_LLCORNER+lower left-hand corner
ACS_LRCORNER+lower right-hand corner
ACS_LTEE+left tee
ACS_NEQUAL!not-equal
ACS_PI*greek pi
ACS_PLMINUS#plus/minus
ACS_PLUS+plus
ACS_RARROW>arrow pointing right
ACS_RTEE+right tee
ACS_S1-scan line 1
ACS_S3-scan line 3
ACS_S7-scan line 7
ACS_S9_scan line 9
ACS_STERLINGfpound-sterling symbol
ACS_TTEE+top tee
ACS_UARROW^arrow pointing up
ACS_ULCORNER+upper left-hand corner
ACS_URCORNER+upper right-hand corner
ACS_VLINE|vertical line

 

RETURN VALUE

All routines return the integer ERR upon failure and OK on success
(the SVr4 manuals specify only "an integer value other than ERR") upon
successful completion, unless otherwise noted in the preceding routine
descriptions.
 

NOTES

Note that addch, mvaddch, mvwaddch, and
echochar may be macros.
 

PORTABILITY

All these functions are described in the XSI Curses standard, Issue 4.
The defaults specified for forms-drawing characters apply in the POSIX locale.

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 TABSIZE variable is implemented in some versions of curses,
but is not part of X/Open curses.

If ch 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.
 

SEE ALSO

curses(3X),
curs_attr(3X),
curs_clear(3X),
curs_inch(3X),
curs_outopts(3X),
curs_refresh(3X),
putc(3).

Comparable functions in the wide-character (ncursesw) library are
described in
curs_add_wch(3X).



 

Index



NAME

SYNOPSIS

DESCRIPTION


Line Graphics


RETURN VALUE

NOTES

PORTABILITY

SEE ALSO



Back to Top

PayPal Logo┬ęCheap VPS LLC - Leader of affordable VPS Hosting Services