https://invisible-island.net/ncurses/man/
curs_border(3x) Library calls curs_border(3x)
border, wborder, box, hline, whline, vline, wvline, mvhline, mvwhline,
mvvline, mvwvline - draw borders and lines in a curses window of
characters
#include <curses.h>
int border(chtype ls, chtype rs, chtype ts, chtype bs,
chtype tl, chtype tr, chtype bl, chtype br);
int wborder(WINDOW *win, chtype ls, chtype rs,
chtype ts, chtype bs, chtype tl, chtype tr,
chtype bl, chtype br);
int box(WINDOW *win, chtype verch, chtype horch);
int hline(chtype ch, int n);
int whline(WINDOW *win, chtype ch, int n);
int mvhline(int y, int x, chtype ch, int n);
int mvwhline(WINDOW *win, int y, int x, chtype ch, int n);
int vline(chtype ch, int n);
int wvline(WINDOW *win, chtype ch, int n);
int mvvline(int y, int x, chtype ch, int n);
int mvwvline(WINDOW *win, int y, int x, chtype ch, int n);
wborder and border draw a box at the edges of the specified window or
stdscr, respectively. Each chtype argument corresponds to a geometric
component of the border as follows:
ls - left side,
rs - right side,
ts - top side,
bs - bottom side,
tl - top left-hand corner,
tr - top right-hand corner,
bl - bottom left-hand corner, and
br - bottom right-hand corner.
If any chtype argument is 0, then curses uses forms-drawing characters
(see addch(3x)) in the following correspondence:
ACS_VLINE,
ACS_VLINE,
ACS_HLINE,
ACS_HLINE,
ACS_ULCORNER,
ACS_URCORNER,
ACS_LLCORNER, and
ACS_LRCORNER.
box(win, verch, horch) is shorthand for "wborder(win, verch, horch, 0,
0, 0, 0)".
whline draws a horizontal line of ch from left to right, and wvline a
vertical one from top to bottom, stopping once n characters have been
drawn or upon reaching the boundary of win. These functions do not
update the cursor position (beyond any motion directed by their "mv"
variants). ncurses(3x) describes the variants of these functions.
These functions return OK on success and ERR on failure.
In ncurses,
o these functions fail if the screen is not initialized; and
o functions taking a WINDOW pointer argument fail if win is a null
pointer.
Functions prefixed with "mv" first perform cursor movement and fail if
the position (y, x) is outside the window boundaries.
Unusually, there is no wbox function; box behaves as one would expect
wbox to, accepting a WINDOW pointer argument.
border, box, hline, mvhline, mvwhline, vline, mvvline, and mvwvline may
be implemented as macros.
Borders drawn by these functions are interior borders.
These functions are described in X/Open Curses Issue 4. It specifies
no error conditions for them.
SVr4 documentation says that these functions return OK "or a non-
negative integer if immedok() is set", referring to the return value
from wrefresh, which in SVr4 returns a count of characters written to
the window if its immedok property is set; in ncurses, it does not.
BSD curses drew boxes with horch in every character cell of the top and
bottom lines of the window, whereas SVr3.1 and later curses, because
its box wrapped wborder, used the default corner characters.
4BSD (1980) introduced box, defining it as a function.
SVr3.1 (1987) added whline and wvline and their variants, as well as
border and wborder, redefining box as a macro wrapping the latter.
curses(3x), curs_outopts(3x)
ncurses 6.5 2025-02-01 curs_border(3x)