28 May
2024
28 May
'24
2:49 p.m.
Paul, you said:/
/
/I'd say an OS is a software system that runs on bare metal (or
equivalent, like a VM) and offers a set of services intended to make
creating and running applications easier. In that sense, RT-11 SJ or
OS/360 PCP are operating systems, just as Linux is. QRQ is on the edge
(it's written for a single application). Similarly, I would not call
FIG-FORTH an OS, nor those other FORTH systems, though admittedly it's
also a bit fuzzy. /
If the file system and basic I/O functions drivers are in ROM what is the difference
between a BIOS and an Operating System.
Technically speaking, for some, the BIOS offers a hardware abstraction level to some more
generic software that runs on top. BIOS means Basic Input Output System. Is that
restricted to the console only? Some systems run their entire "Operating
System" out of ROM?
Let's take a very simple computer, the HP-41C Calculator. The internal 12K or ROM
handled all of the keypad I/O, display I/O, math functions and programming functions.
Each device added contained all of it's drivers in ROM. There was never an
"Operating System" to load but with additonal hardware/software modules even
reading and writing to floppy disks and mini data cassettes was supported. The 12K main
ROM and how the expansion hardware/ROM integrated into it was definitely an operating
system.
On the IBM-PC most boards (that were not just multi I/O or RAM boards) came with their own
drivers in ROM as well and were even called bios extensions. The big difference between
the PC and the HP-41C that the PC needed to load the file system handler (and others as
time when on) from disk to run. Whereas the HP-41C never needed to "bootstrap"
from some kind of media.
By your definition many BIOS's are really operating systems. And if I really want to
pick nits, what you defined as an Operating System is really an application that uses the
BIOS Operating System. Yes, I know, not all BIOS's have enough functionality to
qualify as an operating system.
To spark even further debate, does an operating system require file system capabilities.
Many do not. This furthers my supposition that the BIOS is really the operating system
and what you are calling an operating system is merely an application using the BIOS API
for the required services.🙂
My comments are not intended to inflame but rather to cause further discussion.
On 5/28/2024 2:38 PM, Paul Koning via cctalk wrote:
On May 28, 2024, at 3:24 PM, John via
cctalk<cctalk(a)classiccmp.org> wrote:
From: ben<bfranchuk(a)jetnet.ab.ca>
To:cctalk@classiccmp.org
Subject: [cctalk] Re: terminology [was: First Personal Computer]
Is RT-11 a "real operating system"? What about RT-11 SJ? I would
consider it to be one.
For that matter, what about OS/360 PCP? That's a single task OS, just like RT-11 SJ
only much less efficient.
Is FIG-FORTH an OS? What about POLYFORTH or ZeptoFORTH?
The picture gets particularly muddled when you look at RTOS. For example, it's well
known in hard real-time OS that using interrupts is not necessarily a good plan. A very
successful storage system I worked on ran on a dual core MIPS system. One core ran
NetBSD; the other ran a home-grown RTOS called QRQ that used a polling loop (and no
priorities) rather than interrupts. The benefit of such a design is that its time bounds
are easy to establish, unlike interrupt driven systems where that is certainly harder and
not always possible at all.
I'd say an OS is a software system that runs on bare metal (or equivalent, like a VM)
and offers a set of services intended to make creating and running applications easier.
In that sense, RT-11 SJ or OS/360 PCP are operating systems, just as Linux is. QRQ is on
the edge (it's written for a single application). Similarly, I would not call
FIG-FORTH an OS, nor those other FORTH systems, though admittedly it's also a bit
fuzzy.
paul
The third thing is a real OS. Nobody has one, as
a personal computer.
CP/M and MSDOS does not handle IRQ's. Unix for the PDP-11 is real
operating system but not personal as it requires a admin,and a
swapping media.
This an auld refrain among *nix partisans of the ESR type, but I've yet
to hear someone offer up a real defense of it. Even putting aside what
"handles IRQs" means here (yes, strictly speaking the IRQs on the IBM
PC are handled by the BIOS and/or add-on drivers/utilties, but DOS most
certainly makes use of the facilities provided,) why does that make it
"not a real OS?" What does PDP-11 Unix provide which MS-DOS doesn't to
make one "real" and the other not?
Certainly, nothing about a single-tasking single-user text-based
environment *requires* interrupt-based I/O, even if it may smooth out
performance in some aspects. ...
Or is it multi-tasking capability itself that makes the difference?
Can't see why that should be the case; it's definitely convenient, but
as one person can only be doing so much at any given time, it's also
hard to see that as a *requirement.*
So what, then, consitutes a Real Operating System, and why?