[TUHS] Hypothetical: Could MULTICS have been written in C, if available?

[Douglas McIlroy via TUHS]

> Multics was written in PL/1 which is equally capable and was more
mainstream than C.

IBM hoped it would become mainstream, but when Multics adopted PL/I, it was
only a
draft spec. It had some radical features, e.g. pointers, that broke away
from the
mainstream of the time.

> Trying to squeeze a full PL/1 compiler onto a PDP-7 would have been
> akin to putting ten pounds of nuts into a five pound bag

Amusingly, IBM's goal of compatibility across the whole 360 spectrum forced
them to do just that. The compiler came in  various memory sizes. I heard
that the version for the smallest 360/20s ran as some 60 overlays.

> There's also a matter of taste.  I don't know, but I never got the
> impression that PL/1 was a _popular_ language with the Unix folks
> after Multics. Perhaps Doug or Ken can comment?

True. As I told Steve Jenkin, my PL/I oeuvre comprises exactly
one working program, despite the fact that I helped design the language.
Other Unix people had even less motivation to jump on the PL/I bandwagon.

Doug