Re: The integral type 'byte' (was Re: Suggested method for returning a string from a C program?)

On 27/03/2025 03:24, Janis Papanagnou wrote:

On 27.03.2025 00:21, bart wrote:

On 26/03/2025 18:09, Janis Papanagnou wrote:

[...]

>
I had no interest whatsover in operating systems. I did fine without one
to start with, while CP/M (our rip-off of it) and DOS provided a file
system and a way to launch programs; what else was there?
>

languages like BASIC

>
What language would you have advocated that could fit into a few KB, and
that could run without a proper file system?

 The first that comes to mind was (for example) Pascal. It actually
became available on several platforms. But it was not comparable
to the omnipresent [lousy] BASIC that was inherent part of the OS
in the ROM. (Well, or on a 8" floppy; e.g. in case of the Olivetti
P6060.) There were other languages available; someone (maybe David)
mentioned some upthread. Myself I bought a Simula compiler for my
Atari ST. Simula is a powerful and comparably huge language, so your
"few KB" excuse is not convincing.
 

Many of the BASIC's on home computers were quite sophisticated - the BBC Micro (and later Archimedes) versions were famously advanced.  Of course versions for things like the ZX80 - with 4 KB rom, and 1 KB ram (for screen memory, OS data, interpreter data, BASIC program, and BASIC data) were very limited.
Pascal would have been hopeless on such systems.  A compiled - or even byte-compiled (such as P-code) - language would be totally out of the question.  A minimal Pascal implementation, such as existed for the BBC Micros and the ZX Spectrum, needed more in the range of 16 K rom / program and the same again of ram for source code, compiled / byte-compiled code, and program data.
Remember, these systems did not have the resources you are talking about.  The Atari ST was a monster compared to the popular home computers - 512 KB ram on the cheapest version, compared to more typical 16 KB - 32 KB ranges.  And it had a price to match, way out of reach of most home users.
There are only two high level languages that have had any kind of success on such small systems - BASIC (or variants thereof, as there is no single standard "BASIC" language) and Forth.

I think it was a professor at the university who meant that anyone
who started with BASIC would be incapable of ever doing real CS.

It was Dijkstra who said that.  As usual, his comments were entertainingly exaggerated when made, and then taken out of context.

This is of course nonsense! (And such arguments say more about the
person formulating such non-arguments. - I recall a similar nonsense
mentioned here by someone some months ago concerning OO and Simula
and all other OO languages that took their OO concepts from Simula.)
 The point with BASIC is that if all you know is BASIC without knowing
anything else you probably won't be able to understand the problems
with it. I know you have a broader language repertoire, so I presume
you know BASIC's deficiencies (or at least the deficiencies of those
BASIC dialects that were around until around 1980).
 

That was not Dijstra's point at all - it was the "trial and error" attitude to programming that you got from interpreted languages that he disliked.  However, your point /is/ still valid - people who are only familiar with one programming language will have difficulty understanding its limitations or seeing the benefits of other languages, and tend to look at problems from a perspective limited by their own language.

>
But also at that time - early 80s when Spectrums etc were popular -
there were some wonderful new 16/32-bit processors such as 68000,
Z8000/0 and NS32032, of which only the first survived.

 I've had contact with a couple CPUs back these days; 6502 (6510),
68000, 8080 (Z80), another Intel thing where I forgot the number,
SC 61860, TMS 320 C25. And I read about (but not programmed) a
couple more (the SPARC, one from National Semiconductors) where
I forgot the model numbers.
 The 68000, specifically, is a great example for an inferior CPU
architecture. (Your mileage obviously varies if you think it was
even "wonderful".)

What do you think is "inferior" about the 68k architecture?  At the time, the main business-world competitor, the 8086, was 8-bit with some 16-bit features, and built with a view towards backwards compatibility rather than the future.  The 68k had a 32-bit ISA with a 16-bit ALU - looking towards the 32-bit future while accepting that it had to be cost-effective.

 CPU architectures that I found to be more interesting were SPARC,
the National Semiconductor thing (NS 32016 maybe? nor sure), and
the TMS DSP (where I spent quite some time with), for example.
 

SPARC certainly had some interesting features and concepts.  (I never used it, but read a fair bit about it, and briefly used the Altera NIOS soft core that had some similarities.)  The TMS320C24x DSPs I used were utterly horrible.

But that all was long ago and is meaningless today. Personally
I've occasionally programmed in assembler around 1980-1990, and
you can imagine that I don't care much about that topic anymore.
 

>
Their architecture is not that different from current machines.

 That would be bad news. And I have my doubts that this is true.
(But as said, I don't care much anymore.)
 It's interesting to still see advocates of inferior IT justifying
bad paragons, though. The situation has not changed. - Have fun!
 

There are plenty of things I find disappointingly similar between most cpu architectures.  It's hard for novel ideas to break through.  Part of the blame for that, of course, is the success of C - a cpu design tends to be successful if and only if it is efficient for the C model of programming, other than for a few specialised areas (like graphics work or some highly SIMD-friendly algorithms).  I'd like to see cpu designs with multiple stacks, multiple register banks for fast task switching, hardware support for multi-tasking, locks, atomic accesses, transactional memory, CSP-style message passing, memory allocation, buffer management, etc.  There are countless bits and pieces that could make processors much faster and much more secure for a lot of work.
The XMOS devices are one of the few architectures to come up with really new ideas and have some market success.