[cctalk] Re: MS-DOS

I've always been pro MS-DOS - the earliest version I started with was about 3.20, IIRC. I don't ever recall seeing 86-DOS on shelves, or ever really hearing about it. But CP/M remained fairly popular to mid 1980s (I just mean I knew various friends who daily used CP/M then). A couple issues with CP/M: it never really "broke the 64K barrier", so I've wondered who "pioneered" the segment management needed to make the 1MB conventional RAM seem more contiguous than it really is? (I understand the 640K barrier was just arbitrarily picking 10 segments for end user, and 6 for essentially system reserve - and yes there is more details to that). Maybe it related to the difference between .COM (a 64KB binary sequence, but I think the first 100 bytes reserved for passing from the command line?), and .EXEs that could have enough code to span multiple segments (but does the credit for that go to the operating system, or the compiler writers? or a collaboration between both?). CP/M, as far as I can tell, never tackled "the 64KB barrier" (i.e. was a C compiler for CP/M available that could do x = malloc(100000) and use that as a contiguous allocation from a programmer perspective?). And, what about software interrupts? I recall those huge books detailing the MS-DOS interrupts, so I think one does have to give Microsoft credit towards providing developers with technical details (being somewhat reminiscent of IBM's SHARE groups, in a way-- in terms of advocating/training end users, and constant collaboration in developer conferences). In short, I've proposed QDOS may have truly been the better product at those pivotal months of 1980/1981. DR's 86-DOS was "in the works" and just too late (but years later, I did come to love DR DOS 3.40 over MS-DOS 4.xx, and stuck with DR-DOS up until MS-DOS 6.22). On Thu, Aug 8, 2024 at 12:31 AM maddox--- via cctalk <cctalk(a)classiccmp.org> wrote: