Gpl question: OS libraries

[Sina Bahram]

Hi all,

I was wondering, in GPL 2.0, we have a clause permitting the exception of
needing to provide source for called libraries, if they are part of the OS.

In Linux this probably isn't too much of a problem, but how does one go
about defining, part of the operating system, on other platforms? For
example, in Windows .... Is something like SAPI or DirectX, quote part of
the OS quote?

Thanks for any articles, clarifications, or other pointers as well.

I'm still googling and emailing other contacts, but I feel a lot better
hearing something like this from an actual person as opposed to someone's
blog, *grin*.

Take care,
Sina