Re: [User-mode-linux-devel] Portability

[Jeff D. <jd...@ka...>]

> > Posix compatibility is definitely not enough.  I think the 
> > biggest problem would be the ability to intercept and modify 
> > Linux system calls.  Nothing works without that.
>
> Ah, a light dawns.  I wondered (without wondering enough to learn the
> Linux and uml internals) how you virtualized the machine.  This
> combines with the comments about debugging yourself to explain the
> fundamentals... 

Actually, with an OS that maps reasonably well to Linux, it might not be hard 
to replace the top layer (the bit that intercepts system calls) with its 
equivalent.  It would run its own binaries and map those syscalls onto Linux 
syscalls.

Everything below that layer it Posix, I think.  Except maybe some of the 
mmaping that I do.

				Jeff