Importing some special C functions

[Alex <jrz_dont_want@spam.free.fr>]

Hello,

I'm under windows, and I'm using GNAT 3.15p.

I'd like to access serial links, but without using Win32 Bindings.

so, I have to import C functions like read, write, open, and select.
For most of them, I did not encounter problem.
I suppose the linker uses the C functions it has in the gnat C library.
But it fails for the select function : the linker can't find it.
So, I suppose there is no select function in the C library of Gnat.

That's why I'm asking help about how to do that ? I mean, how making
Gnat importing C functions ?

I've got Cygwin installed, so I guess I could use its C library. But no
idea how to do it.

If someone could help, it would be great.

Thanks in advance,

-- 
Alex