Subject: Re: NetBSD without MMU ?
To: None <netbsd-ports@netbsd.org, tech-embed@netbsd.org, tech-ports@netbsd.org,>
From: Lennart Augustsson <lennart@augustsson.net>
List: tech-ports
Date: 04/12/2002 11:57:57
> : You don't _need_ an MMU to implement fork().... (eg. as in MINIX)
> However, you do have to do some really major evil and hack the compiler to
> make all code PIC-and-then-some (ensuring base register relative addressing
> for all data accesses).
Not at all. Original Unix implemented fork() without PIC. What you do
is that you copy all of the current process to swap space and then you
make that process the parent (well, I guess you could make it the child
if you want). Context switch will be somewhat slow since it will
require a swapping out and in.
Now, this particular solution may not apply if you don't have swap space. :)
-- Lennart