re: "Essentials of Windows for UNIX developers" on-line course goes live!

Mo — Thu, 19 Feb 2004 07:55:00 GMT

Okay, I have a question - as a UNIX developer who does Windows (and WinCE) stuff too.

I originally posted this over at Raymond Chen's blog, but it turns out he doesn't know the answer, and some helpful soul pointed me here, which seems massively more appropriate.

Anyway, on with the question:

All of us good boys and girls who did our homework have known for years that NT's POSIX subsystem (and by association Interix/SFU) support fork().

The Win32 API (as far as I can tell by RTFMing, Googling, newsgrouping, and generally given up trying some time ago) doesn't contain any equivalent - not even a closely guarded one. If I'm wrong, stop me now :)

Assuming I'm on-base up until now, the question is this: POSIX/Interix/SFU all need to get some kind of help from the kernel at some point along the way in order to actually perform the fork. After all, they're subsystems (or a subsystem, depending on how you look at it), not kernel-mode drivers, so they don't have much more access to the MM than I do in my Win32 process. By what mechanism do they get this "help" -- and how POSIX-specific is the help that they get? Specifically, would it be at all possible to utilize this support code - assuming it exists - from within the Win32 subsystem in order to achieve the same thing?

[Unsuprisingly enough, the fact that POSIX apps run in a different subsystem means they can end up being really quite dull -- no "best of both worlds" for developers there]

So, if you know the answer to this, fantastic. If you don't...then apologies for blogspam :)