> How does one correctly initialise a color pair so as only to set the
> foreground color?  (thus preserving the terminal's background)
> 
> Right now I'm using (on -CURRENT, as 1.6.1 doesn't support
> use_default_colors) the following:
> 
>         init_pair(1, COLOR_YELLOW, -1);
> 
> which works, but there's no mentioning of this (the -1) in the manpages
> of -CURRENT, and there are absolutely no checks in the code of curses on
> what to do with -1, it seems (or I'm missing them).

Your code is correct.  The only manual page that mentions colour -1 is the
curses_default_colors(3) page.  I'll add the list of colours and mention
colour -1 on the curses_color(3) page too.  Thanks for pointing this out.

The code that allows colour -1 to be set is in the functions init_pair()
and assume_default_colors() in lib/libcurses/color.c.  The code that parses
the values (and handles colour -1) is in the internal function __set_color()
(which is called from the internal screen refresh function makech() in
refresh.c).

> But later they are saying it does not have to be -1 necessarily, but
> can be any negative value:

We only accept -1.  As we are emulating an ncurses interface, we should
accept any negative number here.  I'll change init_pair() to treat any
negative number as -1.  I think ncurses should really have defined (say)
COLOR_DEFAULT here, for consistency with other curses definitions.

> And I've observed that 0 also works as background color in NetBSD
> curses, but negative values other than -1 don't work, while in ncurses
> they do.

0 is COLOR_BLACK (/usr/include/curses.h), which might be the colour of your
terminal background.  Also, note that changing colour pair 0 has no affect
and that we deviate from the ncurses implementation by allowing colour -1
to be set even if use_default_colors() has not been called.

> Does this mean our curses implementation is flawed, or the documentation
> is incomplete, or both?

A bit of both.

J

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