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 vline(chtype ch, int n);
int wvline(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 mvvline(int y, int x, chtype ch, int n);
int mvwvline(WINDOW *win, int y, int x, chtype ch, int n);
The border, wborder and box routines draw a box around the edges of a
window. Other than the window, each argument is a character with
attributes:
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 of these arguments is zero, then the corresponding default
values (defined in curses.h) are used instead:
ACS_VLINE,
ACS_VLINE,
ACS_HLINE,
ACS_HLINE,
ACS_ULCORNER,
ACS_URCORNER,
ACS_LLCORNER,
ACS_LRCORNER.
box(win, verch, horch) is a shorthand for the following call:
wborder(win, verch, verch, horch, horch, 0, 0, 0, 0).
The hline and whline functions draw a horizontal (left to right) line
using ch starting at the current cursor position in the window. The
current cursor position is not changed. The line is at most n
characters long, or as many as fit into the window.
The vline and wvline functions draw a vertical (top to bottom) line
using ch starting at the current cursor position in the window. The
current cursor position is not changed. The line is at most n
characters long, or as many as fit into the window.
All routines return the integer OK.
This implementation returns ERR if the window pointer is null.
Functions prefixed with "mv" first perform cursor movement and fail if
the position (y, x) is outside the window boundaries.
border and box may be implemented as macros.
The borders generated by these functions are inside borders (this is
also true of SVr4 curses, though the fact is not documented).
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.
curses(3x), curs_outopts(3x)
ncurses 6.5 2025-01-18 curs_border(3x)