> As I remember, way back in the mists of 1990 when I first encountered a NeXT
> box, one of the principal reasons for selecting the Mach 2.x micro kernel was
> "mach messaging". This was a unified mechanism for almost all IPC both within
> one host or distributed over a network, where eg. sockets (netork or unix
> domain), pipes etc. were seen as abstractions of the core messaging function.
> This fitted very well with the general OO design philosophy of the company.
> If anyone has access to a copy of the socket(2) man page from any NeXTSTEP
> version, I dimly remember there being an informative paragraph about this
> point.
This is mostly true, but the Mach kernel they shipped definately wasn't
what I'd call a "micro kernel". It was based on the earlier CMU monolithic
4.3BSD Mach kernel. At the time, we had a source license for their
kernel (at least most of; not device drivers, feh!), and this was very
clear.
> Whilst Mach messaging was not commonly used directly in the Unix userland
> which was pretty much stock BSD 4.3, it was very important in the AppKit ---
> NeXT's real stock in trade.
In fact, the IPC between the appkik/user processes and the Display PostScript
server really made use of this, could result in very high performance
when moving large bitmapped images, etc.
I would love to have a UI available these days; it was worlds better than
X at the time, and frankly, still better than what we have today. The
afterstep and WindowMaker guys have made some progress emulating the
visual interface. But can you imagine trying to run GNOME or KDE on a
25Mhz 68030 today?
louie
To Unsubscribe: send mail to [EMAIL PROTECTED]
with "unsubscribe freebsd-hackers" in the body of the message
