Subject: Re: MacOS X binary compatibility status
To: None <tech-kern@netbsd.org>
From: Christos Zoulas <christos@zoulas.com>
List: tech-kern
Date: 11/10/2002 23:42:50
In article <1flgb6t.a3glosl8o7wgM%xavier.humbert@xavhome.fr.eu.org>,
Xavier HUMBERT <xavier.humbert@xavhome.fr.eu.org> wrote:

It is always a good thing to check your facts for correctness before
making statements like this. From the kernel perspective MacOSX/Darwin
mostly resembles NeXT, which in turn is Mach based. As such, the
challenge is to implement the Mach traps which are mainly used to
do the process setup and dynamic linking. This could be the base
of other mach based emulations such as GNU/Hurd (no hurry there),
and Tru/64 (most programs don't use the traps, so it is not a big
win), NeXT itself.

>Since MacOSX/Darwin is already largely based on NetBSD, with a few adds
>from FreeBSD, is there an interest other than technical performance to
>have MacOSX on NetBSD ?

This is one of the questions that the emulation code wants to answer
and I am personally curious about. It could be the case, that due to
the nature of the Mach kernel and the overhead of executing Unix
traditional system calls on top of Mach, that the emulated code will
run significantly faster under NetBSD.

>Please, there is no offence, the answer "because it's fun" sounds
>perfectly reasonable to me, but is there another ?

It is always fun, and a learning experience.

christos