Making a MS Windows compatible OS, is it legal?

[K.J.]

Okay, here's something that I've been wondering,

Is making a MS Windows compatible OS legal? ???

What I mean is, is it legal to make an OS that can run Windows apps and use Windows drivers. Both of these would mean making a Win32 compatible API. So, is the API copyrighted/patented or can it be?

If not, then would the Windows emulator for Linux(yeah I know, it's not actually an emulator), WINE( http://www.winehq.org ) be legal?

K.J.

[Kernel Panic]

Take a look at http://www.lindows.com. They've been recently sued by MS, but not due to supporting windows apps (because of name similarity, IIRC). I guess API could be copyrighted, but am sure MS will never do this.

[Tim]

As I see it (and I'm not a lawyer), Microsoft can copyright Windows, but they can't copyright the Windows API specification. They could try to patent the Win32 API, but it would be very unlikely to go through because it is so similar (in concept) to most other operating system APIs. So you couldn't gain Windows compatibility by copying KERNEL32.DLL etc. from Windows, but AFAIK there's nothing to stop you writing a KERNEL32.DLL which supported the same API.