Re: is there a version of unix written in Ada

[Andreas ZEURCHER <ZUERCHER_Andreas@outlook.com>]

On Friday, July 24, 2020 at 5:11:49 PM UTC-5, gdo...@gmail.com wrote:
> is there a unix like OS written completely in Ada?

In 1981, there in fact was one that had 2 public releases with work in progress on Version 3:  iMAX-432, depending on how puritanical one wishes to be about what is or is not Unix-like.  (iMAX-432 was far more Unix-like than, say, MVS-like or CP/M-like.)

If anyone has an inside negotiating track at Intel (or the contracting firm that Intel hired to develop it), perhaps they would be willing open-source the old iMAX432 operating system that was released for the iAPX432 processor that was designed from the ground up to have an Ada-centric instruction set.  Although it was more Multics-esque than Unix-esque* and although it was written specifically for the iAPX432 (and thus had much iAPX432-only assembly language), it should be relatively easily transliterable into other ISAs because the iAPX432 ISA more closely resembles Java bytecode, LLVM bitcode, and C# CIL/MSIL than other rudimentary machine codes of that era, due to being object-based/OO-lite in the hardware's machine code (which is what doomed the iAPX432 in the early 1980s:  it was so complex that it required 3 separate IC dies in 3 separate ceramic packages, and it ran relatively hot).

* Conversely, both Multics & our modern Unix are nowadays birds of the same feather despite the multi-decade dislocation in time from each other, due to both having:
1) multiple threads per address space;
2) multiple DLLs per address-space;
3) multiple memory-mapped files (i.e., mmap(2) in Unixes versus snapping segment-files in Multics);
4) IPC based on multiple threads or multiple processes pending on a single message-queue;
5) soft real-time thread scheduling priorities in addition to time-sharing scheduling priorities;
and
6) a GNU-esque long-form whole-words and short-form abbreviated-letters of each hyphenated command-line flag
are birds of much the same feather, as opposed to 1970s-era spartan Unix that abhorred all of these multiplicities, hence AT&T's uni-based name in AT&T's 1970-divorce-from-MIT's/GE's/AT&T's/Honeywell's-Project-MAC in defiance of Project MAC's multi-based name, because the tongue-in-cheek humor of Unix's name as eunuchs is Multics castrated.  Eschewing singleton this and singleton that, Unix nowadays is no longer a castrated eunuch, due to reintroducing a cousin-like variant of nearly every multiplicity feature of Multics other than the multiple rings (unless one counts VM hypervisors nowadays as reintroducing a cousin of that one too).

https://en.wikipedia.org/wiki/IMAX_432