From owner-freebsd-hackers@FreeBSD.ORG Wed Apr 4 14:39:04 2007 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id A10EC16A403 for ; Wed, 4 Apr 2007 14:39:04 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [209.31.154.42]) by mx1.freebsd.org (Postfix) with ESMTP id 3A8D513C457 for ; Wed, 4 Apr 2007 14:39:04 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from fledge.watson.org (fledge.watson.org [209.31.154.41]) by cyrus.watson.org (Postfix) with ESMTP id 3AF30475C0; Wed, 4 Apr 2007 10:39:03 -0400 (EDT) Date: Wed, 4 Apr 2007 15:39:03 +0100 (BST) From: Robert Watson X-X-Sender: robert@fledge.watson.org To: Mike Meyer In-Reply-To: <17939.44784.420806.421633@bhuda.mired.org> Message-ID: <20070404153559.Y18288@fledge.watson.org> References: <20070404130249.GA41671@kukulies.org> <17939.44784.420806.421633@bhuda.mired.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: freebsd-hackers@freebsd.org Subject: Re: Mac OS underlying FreeBSD - does it run Linux emulation? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 04 Apr 2007 14:39:04 -0000 On Wed, 4 Apr 2007, Mike Meyer wrote: > In <20070404130249.GA41671@kukulies.org>, Christoph P. Kukulies typed: >> does anyone know whether one can run Linux applications under the underlying >> FreeBSD of the MAC OS (on an Intel Core Duo mini Mac)? > > No, you can't. The "underlying" FreeBSD is userland code; not kernel code. > The OSX kernel is based on Mach. While it's true you can't run Linux binaries on Mac OS X, it's not for the reason you're suggesting, and your statement regarding FreeBSD kernel code in Mac OS X is simply incorrect. The Mac OS X kernel, XNU, contains significant quantities of FreeBSD kernel source code, including a FreeBSD-derived VFS and network stack. Other parts of the kernel, such as the scheduler and VM system, are derived from Mach. While the FreeBSD-derived code has been significantly modified since it was originally forked, a lot of code moves backward and forward between the platforms: the FreeBSD audit subsystem is derived from the Mac OS X audit subsystem, and Mac OS X's smbfs and MAC Framework support are derived from FreeBSD. Robert N M Watson Computer Laboratory University of Cambridge