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I agree that Unix was fundamentally different in many ways, but CP/M wasn't a copy of Unix either; if anything, RT-11 was slightly more Unix-like than CP/M was.
by kragen 2y ago
I agree that Unix was fundamentally different in many ways, but CP/M wasn't a copy of Unix either; if anything, RT-11 was slightly more Unix-like than CP/M was. Because CP/M was evidently worse than RT-11 in many apparently unnecessary ways, I suspect that it was drawing from some other source.
I didn't suspect any nefarious intent, but if I didn't tell you it had happened, you would never have known. My apologies if it sounded like I was blaming you for it.
- WalterBright 2y agoI don't see any heritage of unix in CP/M, but I do see a heritage from DEC. Not an exact copy, of course. > if I didn't tell you it had happened, you would never have known That's right, and now I know. Thanks! > My apologies if it sounded like I was blaming you for it. Thank you. Apology accepted!
- kragen 2y agoDo you have any clues about which DEC system it might be drawing these other elements from? I mean specifically: - FCBs. - A command interpreter prompt ending in ">" rather than "*" or ".". - 8-character filenames (rather than 6). - ASCII filenames (rather than RADIX-50). - Drive letters. - PIP switches in square brackets rather than introduced by slashes. (Some TENEX programs evidently enclosed their switches in parentheses, but the ones I've seen so far don't use square brackets.) - Launching programs from the command interpreter with command-line arguments, like Unix. Maybe Kildall thought all these things up himself, but I suspect some previous DEC OS was their origin. But it isn't RT-11, TENEX, the DEC 10/50 monitor, TOPS-20, or VMS. I want to emphasize I'm not claiming that these are advances or innovations. I'm just saying that they suggest some other influence.