OSX

From: Brian Chase <vaxzilla_at_jarai.org>
Date: Thu May 29 14:20:00 2003

On Thu, 29 May 2003, Jay West wrote:

> Odd.... Apple hired Jordan Hubbard (lead developer for FreeBSD) to
> head up OSX development, and I was quite sure I saw an article where
> Jordan stated the kernel and underlying OS was in fact FreeBSD. I'll
> check into this...

NEXTSTEP was a effectively a NeXT customized CMU Mach microkernel with
lots of 4.3BSD mixed in with it. OS X is a revamped version of Mach
with FreeBSD (and other more modern BSDs) mixed into it. I'm sure
Jordan Hubbard was very instrumental in helping to update the OS to
benefit from FreeBSD's code, but OS X is definitely not FreeBSD at its
core. It's Mach. I mean, even the name of /kernel/ file is "mach" or
rather "/mach_kernel" under OS X.

Also, the OS X hostinfo command still reports the Mach version
information as was done on NEXTSTEP systems:

On my iMac:

  % hostinfo
  Mach kernel version:
           Darwin Kernel Version 6.6:
  Thu May 1 21:48:54 PDT 2003; root:xnu/xnu-344.34.obj~1/RELEASE_PPC


  Kernel configured for up to 2 processors.
  1 processor is physically available.
  Processor type: ppc7450 (PowerPC 7450)
  Processor active: 0
  Primary memory available: 256.00 megabytes.
  Default processor set: 70 tasks, 141 threads, 1 processors
  Load average: 0.52, Mach factor: 0.60

On my NeXT cube:

  % hostinfo
  Mach kernel version:
           NeXT Mach 3.3: Tue Jul 13 10:33:44 PDT 1999;
  root(rcbuilder):mk-171.14.obj~22/RC_m68k/RELEASE_M68K

  Kernel configured for a single processor only.
  1 processor is physically available.
  Processor type: MC680x0 (68040)
  Processor speed: 25 MHz
  Processor active: 0
  System type: 2
  Board revision: 0x0
  Primary memory available: 64.00 megabytes.
  Default processor set: 38 tasks, 66 threads, 1 processors
  Load average: 0.40, Mach factor: 0.83

The information about OS X being FreeBSD with a pretty Apple GUI on top
of it tends to come from some misguided slashdotters who lack historical
perspective. That's not to slight FreeBSD's contributions, but they're
better considered as "renovation work" to what had already been in place
for a decade.

-brian.
Received on Thu May 29 2003 - 14:20:00 BST