17 Jun
2023
17 Jun
'23
3:02 p.m.
On Fri, Jun 16, 2023 at 6:04 PM ben via cctalk <cctalk(a)classiccmp.org>
wrote:
On 2023-06-16 4:56 p.m., Chuck Guzis via cctalk
wrote:
The PDP-11 never had useful virtual memory, the 8k segment size was simply
too large to do anything other that interprocess protection and have a
separate address space per process. It never had a useful mmap, so it never
had useful shared libraries, it couldn't demand load binaries (they were
loaded entirely at startup), there was no copy-on-write sharing. Not sure
what 'proper memory management' meant, so can't comment on that....
AT&T PDP-11 unix never had TCP/IP from AT&T, though an early NCP version
existed and BBN's TCP stack made V7 and newer have TCP. The BSD side had
TCP/IP, running in a "separate" process from the kernel (it ran in
supervisor mode, to get more address space out of the PDP-11 architecture
while sharing the data segments). 2.9 had TCP/IP, but it wasn't until 2.10
or 2.11 that it was really stable.
How many OS's are complete in design that you don't need to bypass
On 6/16/23 12:48, ben via cctalk wrote:
Was that quote written for version #1.
At risk of being a troll, when did Unix (PDP 11) not have all the the
above. Other than TCP/IP networking, I don't see any of above features
desirable, as I feel a need for more real time operating systems.
What cpu?
Minix was 16 bit code only. I suspect 16 bit code here as well.
Remember 32 bit code is 2x the size of 16 bit stuff.
32-bit, I'm afraid. To quote:
WHAT IS LINUX?
Linux is a Unix clone for 386/486-based PCs written from scratch by
Linus Torvalds with assistance from a loosely-knit team of hackers
across the Net. It aims towards POSIX compliance.
It has all the features you would expect in a modern fully-fledged
Unix, including true multitasking, virtual memory, shared libraries,
demand loading, shared copy-on-write executables, proper memory
management and TCP/IP networking.
It is distributed under the GNU General Public License - see the
accompanying COPYING file for more details.
--Chuck
the OS like MS DOS.
I've evaluated several router products, years ago, that just used Lnux or
FreeBSD to load an application that took over the machine...
Warner