> On May 6, 2025, at 11:32 PM, Steve Lewis via cctalk <[email protected]>
> wrote:
>
>>>> OS/360 TSO BASIC, pgm-nr 5734-RC2 round 1971
>
> Interesting - then I wonder why in 1974 they bothered to build a S/3
> emulator into the IBM 5100. They had already done the S/360 emulator and
> gotten APL working, so why not use this OS/360 version of BASIC?
I wonder if you might be making unwarranted assumptions about the extent of
what is encompassed by the emulation. It’s at least plausible that the state of
the emulation required for implementing the APL interpreter was missing some
non-trivial set of features required by the BASIC interpreter.
It’s also worth considering, as you point out, that perhaps the BASIC
inerpreter depended on some OS services. APL\360 had originally been its own
standalone timesharing environment. I’m unsure of whether that situation was
fully at an end by the time of APL\360 on DOS and MVT (1969ish) but I don’t
doubt the standalone code was likely still reasonably fresh by the time work
was underway on the 5100. The S/3 BASIC may have been in a more reasonable
state for adapting to standalone operation on the 5100. I haven’t kept up with
all the scholarship around the history of the 5100 but it’s also not exactly
implausible that there was some phase of the project where the thing had been
two separate products.
ok
bear.
