Microsoft open sources GWBASIC

Eric Smith spacewar at
Tue May 26 14:35:44 CDT 2020

On Fri, May 22, 2020 at 1:54 PM ben via cctalk <cctalk at>

> On 5/22/2020 1:38 PM, Rod Smallwood via cctalk wrote:
> > I remember sittig in the DEC Ealing (London) Office in 1975 watching a
> > programmer work on TOPS 10
> >
> > That was DEC's mainframe operating system.
> >
> > A foot high of printout all in assembler!!!
> But remember mainframes after 1960 (compared to the 50's)
> where a joy to use with assembly.
> Only afer 1975 came out did you have the extra memory
> (4K drams) and languages like C with structures did O/S's
> change.Ben.

"did O/S's change" in what way?

The IBM PL/I F compiler was available in 1966 and PL/I has structures. It
was usable on all "real" System/360 machines configured with 64KB or more
of memory, so even a 360/30 could be used, but not a 360/20, which isn't
actually a 360.

There was a PL/I D compiler that would run under DOS/360 with only 16KB of
memory, but it was a very restricted subset of PL/I; I dodn't know whether
it had structures.

ALGOL W also appeared in 1966 and had structures, known as records.

Of course, COBOL is even older and also had structures.

Most sensible people did not wait until 1975 to start using high-level
languages, unless they had either tiny machines or real-time requirements
that couldn't be met with a high-level language.

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