процедуры манипулирования цветом curses (curses color manipulation routines)
Портативность (Portability)
This implementation satisfies XSI Curses's minimum maximums for
COLORS and COLOR_PAIRS.
The init_pair routine accepts negative values of foreground and
background color to support the use_default_colors(3X) extension,
but only if that routine has been first invoked.
The assumption that COLOR_BLACK is the default background color
for all terminals can be modified using the
assume_default_colors(3X) extension.
This implementation checks the pointers, e.g., for the values
returned by color_content and pair_content, and will treat those
as optional parameters when null.
X/Open Curses does not specify a limit for the number of colors
and color pairs which a terminal can support. However, in its
use of short for the parameters, it carries over SVr4's
implementation detail for the compiled terminfo database, which
uses signed 16-bit numbers. This implementation provides
extended versions of those functions which use short parameters,
allowing applications to use larger color- and pair-numbers.
The reset_color_pairs function is an extension of ncurses.
