MSX-DOS (1) uses FCBs and a single root directory
MSX-DOS (2) also uses file handles and supports subdirectories
MSX-DOS (both versions) build on a low-level driver which controls the floppy/hard drive. This came in ROM and included higher-level disk handling (file operations, Disk-BASIC etc). The "DOS" part came on a floppy (MSX-DOS.SYS/COMMAND.COM or MSX-DOS2.SYS/COMMAND2.COM).Yes Microsoft was involved here too. Note that MSX-DOS offered some CP/M compatibility: some programs pulled straight from CP/M (Z80 flavour) could run under it. Some functions deal with CP/M-derived 128-byte "records" (from CP/M floppy formats' sector sizes) rather than byte sizes. But no CP/M disk formats were supported afaik.
Other than that, MSX-DOS2 offered some memory management functions for MSX2's memory mapper. Not sure if equivalent functionality was included in MS-DOS 2?
https://github.com/microsoft/MS-DOS/blob/main/v2.0/source/CO...
The problem with changing / to - was, that under MS-DOS command line parsing was left completely to a a loaded program, which then would had to know how to find out this change and act accordingly. And if not only MS-DOS std. utilities behaved properly and others not so much. Thus causing confusion which perhaps then lead to dropping that feature 3.0 onwards.
I think it was also before 2.0 or at least what delivered with Apricot PC (UK made PC) 1.25 which I tinkered with few days as we had it on display from Finnish importer ARAIC Rautakirja Oy (Finnish railways VR magazines and other related travel reading importer, also keeper of the R-kiosks). A very nicely built non IBM PC compatible PC with good graphics and then uncommon 3.5" 70kb disk drives before Apple Macintosh made the more popular.
https://www.homecomputermuseum.nl/en/collectie/act-computers...
e: Now did it change also path separator from \ to / ? It may have done it also. I bit later work more with Xenix and can't remember for sure. Starting from 286 versions SvR2.x, 386 SvR3.x up till SCO UNIX SVR4 early 90's and less with MS-DOS besides maintaining couple of TSR's I had written and just checked every MS-DOS release that those still did work.
s/ARAIC/AFAIC/g s/70kb/720kB/g
And in the many decades and OS rewrites since, they have long since corrected this mistake... right?
It was then COMMAND.COM ie. Dos command line did not do that. And there were alternatives like something called 4DOS which I did never use, but those could have done it. Or did they?
I have't used Windows for quite long time. And I do not know if CMD.EXE or PowerShell whatever its name are any better. Maybe someone knowing would like to comment this.
Powershell is a completely different model where native commands run in-process, you can import commands and invoke APIs from arbitrary .NET assemblies, and then the PS runtime handles all argument parsing (and many other things). But it also lets you invoke and interop with arbitrary command-line executables and then those do their own parsing like they always have.
So is that CreateProcess much different from nix execve() which passes just a pointer to string of executable first followed by pointers to arguments *argv[], and process environment same way *envp[]?
Thus it is the shell which responsibility is to expand all wildcards before passing to that executable arguments nix systems, which do not expand any wildcards itself before passing to executed program.
I'm no Windows programmer so, genuinely what's the difference from point of executed program and just that Windows any shells do not expand wildcards etc. ?
My previous post when I did mention that alternative c0.obj (not lib, sorry) that I for example had about 36 years ago from somewhere was a nifty modified trick which took that plain dumb MS-DOS COMMAND.COM passed string and instead just making it a char *argv[] array first expanded wildcards before your main() got control. It did work very well and saved quite bit of effort when I ported some tools to MS-DOS and I think there was another version of it for OS/2 (1.something) that I used also.
I did not have to add ported software from unix any command line expanding code myself because that alternative startup c0.obj did it for me. Shame I do not remember where I got it and who did it, but it was really good. Now thinking of it perhaps it was from Compu$erve some forum or WSMR-SIMTEL20 archive.
I remember that also Fabrice Bellards lzexe and something spawnsq() (not sure about exact name any more) library also was in use. The latter swapped (saved out file) out running most of MS-DOS program before executing like execve() and freed a lot more memory to run that other program then loading it back when called program was done. I think it used something like 8k memory while resident when other called was running. Which was often enough and no need do any horrible .BAT rewrite tricks to able to accomplish same functionality.
Linked post is quite good and had forgotten completely XEDOS mentioned Byte article.
try making an AUX directory, or CON file, or PRN
I never did any CP/M programming, so the whole FCB-based file manipulation API in MS-dos just seemed like strange old cruft to me. Had I been exposed to CP/M the Unix inspiration behind the handle-based API would have been a lot more apparent. (I got in about the MS-DOS 3.3 timeframe...)
What a strange world it would have been in MSFT got IBM to buy into the Unix path separator.
Using the backslash: one of those incredibly idiotic things that caused untold misery and time waste further down the road. Future generations cursed the day.
https://www.os2museum.com/wp/why-does-windows-really-use-bac...
The Future of Xenix, Bill Gates Interview on Unix World, back in 1985
Having learnt UNIX on Xenix, I know how expensive it was, we had a single tower that the teacher carried on into class, while we in groups of 2 students had about 15 minutes time slots to try out our applications that we prepared on MS-DOS ahead of time with Turbo C 2.0.
And that approximate doubling, in RAM requirements, year by year (compare to Moore's Law for hardware!) for Microsoft's OS'es, has got us, fellow students of computer history, to where we are today -- with Microsoft OS'es being the size that they are and requiring the RAM that they do!
And it all started with upgrading (or "upgrading", take your pick of term!) an 8KB OS to a 20KB OS! :-)
-- Martin Reiser, quoted by Niklaus Wirth
Interesting. At my old job I got my hands on Wang IN/ix around 1985, a 16 bit UNIX.
It ran on an 8086 but needed 512k memory. It ran fine. I wonder if memory was the main issue ? But seems the issue was probably memory for IBM and MS
Here is one, https://github.com/RetroBSD/retrobsd. This is for the pic32, so I may be wrong about the 16-bit thing.
I don't know if anyone has done it but it looks like it could fit, perhaps not on a original 8086 PC, but perhaps a 286 with 640K.
I could get the extra 48KB memory for less than IBM charged. More importantly, double sided floppy drives were already on the market but you couldn't get them from IBM at any price.
So I went to a local component supplier and got a pair of double sided drives. They worked "out of the box" in DOS, but unsurprisingly, only side 1 of each drive showed up as A: and B: drives.
So I wrote a TSR to add C: and D: drive letterss which were side 2 of each drive.
It was super easy.
Later I heard about a fancier TSR that combined side 1 and 2 of each drive into a single drive letter with twice the capacity.
But that was a much more complicated task, and I was happy enough with my four-drive-letter solution.
I had one of these in mid 1982 to late https://en.wikipedia.org/wiki/IBM_Personal_Computer
But only the first 256 KB was on the motherboard, you needed a memory expansion card for the extra 384 KB, and I don't think they really existed in 1982.
Actually, you could somewhat break the 640KB limit in the early days (not that most people could afford that much RAM) days. Until EGA came along in 1984, there was free address space upto 704KB that you could use as conventional memory without much issue (or 736KB if you limited yourself to CGA).
And later we had the mess of EMS, which would work on the original 5150 with the right expansion card (and the right software to take advantage of it, like Lotus 123)
Some clone makers quickly found out ways take advantage of that space adding more RAM there. Then bit later it came area where you could even map over 1MB placed memory blocks there with a config.sys loaded driver.
Nevertheless, writing system code in assembly was probably going to cause a lot of insomnia and other side effects, especially when Microsoft was far from the domination force on IBM PC.
Gotta find some time to read some of the code to chill.
Fortran 77 manual for UNIX, https://www.unix.com/man_page/v7/1/f77
You can find plenty of other examples, when doing digital archaeology.
It tells me more about some people not being curious enough to read documents and explore environment they work than others apparently.
Assembler generating was long time a standard feature of compilers simply because writing the assembler code was easier than directly runnable or linkable object code. And for language designer and compiler programmer it was easier to read verifying correct code generating that way. Why bother writing assembly compiler, linker etc. when you usually already had them in the system that time.
Then later it changed bit as vendors did not any more ship any or just some crippled compliers to compile just a new kernel with the base system to curb their language competition. Which made third party compilers had to either provide with complete set their own creating executables or ask buyer also licensing system vendor compiler toolkit which they would not otherwise need. That then caused prospect third party compiler customer add that licensing fee top of offering and compared which option they would buy if any. That was time when developement toolkits started changing. Under MS-DOS there never was compiler shipped with it that was a situation all the time, but with the minis and larger systems more what described here above.
ps. I think you get much too wound up about C-language. For a long time there was no real alternative use to cross environments compatible way developing thing without major rewrite each platform. That what mattered more than anything else then and in some sense also to some these days also. And no language needs to be put on pedestal like you wrote message you already changed or deleted so that I did not get to answer.
It's easier to directly generate binary object code than assembly. It also makes for a way, way faster compiler. Also, one of the first programs I wrote when developing my compiler was an object file disassembler.
What irks me is this mystical selling point, have you ever tried to write portable C code in K&R C without it being full of #ifdefs?
As you point out, people are not curious enough for what is outside of their bubble and take the marketing message as is.
Even more so, when knowledge was spread via the local library and what magazines one could get their hands on.
Yes, mostly proprietary third party systems which abtracted complexities away from programmers placing their trust to that often not even sure your language vendor was not belly up or with good luck purchased by someone else who then told you we do not support it any more next year. And left you to deal with that. Not fun, not even close I may add. I know who weren't so lucky and had to gather pieces at least mostly rewriting things again new toolkit.
Software development invests in that written code and you learn to appreciate that when you got a lot of it understanding how large and costly task it would be to rewrite another language. Especially then it was that. Now LLM's, much better IDE's etc help a lot with that. Today standards thinking you do not make fair comparison what it was back then.
>...have you ever tried to write portable C code in K&R C without it being full of #ifdefs?
Yes I have done it, not just tried. It wasn't too bad after all when you knew how to do it. Most of systems dependent were hidden away by ourselves to .h files and some to libraries we did. That time it was common thing to teach even, and if not learn from others code how to do it.
That way we knew we had better chance easier to port it something even remotely close existing kind of platforms and OS's. Investment in written software as too great to ignore.
But, did you lately or when did last time write software without relying those abstractions being hidden away either device vendor language libraries or third parties modules?
While you think of it, let me tell you that this situation where we are now is so much much less diversity with our target systems and plenty of programming languages with multitude of good libraries and ready made modules do not compare at all to what situation was end of 80's. Comparing software development effort today's languages and tools by then doesn't make sense at all. Everything was so much slower and time consuming.
That area where C-language is still relevant is now much narrower, but there still are niches where I understand it fairly well. I also understand that you don't get it but that is not a my problem, it's more of a you problem if that irritates you from my point of viewing this matter.
But whatever written here for before above, I see no value continuing this argument with you any more. If you haven't this far understood what I tried conveying there is no hope with me you will eventually get what I try to explain.
So by that I'm wishing you a nice day, cheers.
I might also add that I was surprised that you lost an opportunity to advocate for D, which what I was actually hitting for with that remark alongside a smiley.
I used it as example, as I could have used any other compiled language, including D.
But when Turbo C with assembler (TASM) came out those were just great. And by that asm output generating feature it was often way faster way to write something first in C, translate to asm and go from there do what you wanted with that asm directly. I'm not sure which higher level compilers came with that feature, but once available it was many times just great thing to have for sure.
https://en.wikipedia.org/wiki/ST-506/ST-412
https://www.google.com/search?client=firefox-b-d&q=ST-212+ha...