Re: [hackers-il] Re: More SchemeOS Brain Dumps
- On Tue, 23 May 2000, Gaal Yahas wrote:
> Sounds like you're getting non-preemtive multitasking here. How doesWell, since it's a user-level process, it's not for the kernel to know,
> the scheduler jump to a different procedure when the current one's
> time is up?
but it simply calls a stored continuation.
> What is your handle on a context anyway, if not a process?A continuation. A CONTINUATION. I've said it about 50 times in my last
post. For a good introduction on continuations, consult any advanced
> In what sense can you then say that p is not "really" a process?In the sense that it does not have a seperate address space.
> > That gives us primitives to implement both "processes" and "threads"You'll have a bug. But the system will not crash. Mutexes will be simply
> > inside Scheme, and because scheme is "safe" (as opposed to C), it is
> > possible to do so without ugly race conditions.
> Is it? What if I'm touching one global in two different procedures?
(set-timer #f). Of course, you might send-box set-timer away and have
a higer level mutex creation mechanism. But that's, again, a library
> I am certainly yet to understand everything you're planning to do,Whoever called the procudure. Don't think "processes", think "thunks"
> but it seems to me that problems of security (I'll leave IPC aside)
> still exist by another name. Who does decisions about a "process"'s
> Can a procedure that started with permissions to oneLoads of ways: e.g., you can replace the security model wihtout rebooting.
> set of symbols gain the right to access a different set? How? I
> imagine you have an idea of some protocol by which a called proc
> may talk with its caller and ask for these privileges: sure, but how
> is this essentially different from putting security in a kernel?
I'm trying to write an a good kernel which can be used reliably for a
number of things.
For one thing, sand-boxing procedures will allow me to have a good way to
deal with ILOVEYOU.
Moshe Zadka <moshez@...>
http://www.linux.org.il -- we put the penguin in .com