On Mon, May 18, 2020 at 8:05 AM Tony Finch <
dot@dotat.at> wrote:
BCPL and B were also word-based languages.
Yes, that was the style of the systems language. IIRC PL/360 worked the same way too.
The PDP-7 was a word-addressed machine.
If I understand the history correctly, the move to NB then C was
partly to make better use of the byte-addressed PDP11.
I never used NB, so you'll have to ask someone like Ken or Doug, as to when the language became 'different enough' that Dennis felt it was time to rename it. From conversations years ago with dmr, I was under the impression the original additions were considered 'syntactic sugar ' at first -- hints to help him generate better code for the PDP-11 (like 'register'). I think Steve was at Waterloo and still using B and when he returned to MH, C had appeared, but he might be able to shed some light on the transition.
Clearly the byte address behavior of the 11 had a heavy influence in C. As I said in my earlier email, I've some times wonder what would have happened to the language if the data units had been: byte, word, ptr only [or if DEC marketing had not screwed up with how BLISS was released - another story for COFF I suspect].
Clem