configure: add ncursesw detecting [try 2]

[Dmitry Timoshkov]

"Vitaly Lipatov" <lav at etersoft.ru> wrote:

> We try to rewrote code in universal manner, but old curses code 
> in wineconsole had many hacks and we are changed some parts 
> anywhere.
> I need to accept this patch for detecting ncursesw. Then we can 
> send next patches for unicoding.

Your patch introduces a lot of #ifdef's, that's not something
to be easily accepted. According to the info I quoted an old code
is source compatible with ncursesw, so you shouldn't need #ifdefs
at all, at least in theory.

> I do not know about function redefining, there are incompatible 
> function's arguments (cchar_t vs wchar_t) and it needs various 
> code...

Then existing code needs to be fixed to be compatible with old and
new (redefined) interfaces.

> As I see we need use libncursesw as the main curses library, and 
> have old curses support for compatibility with some old systems.

That's why fixing existing code is preferred to changing it and
potentially breaking compatibility with normal ncurses.

-- 
Dmitry.