[Info-vax] Creating an open source version of VMS, was: Re: OpenVMS Hobbyist Notification

[Simon Clubley]

On 2020-03-12, Arne Vajhøj <arne at vajhoej.dk> wrote:
> On 3/12/2020 7:14 PM, Simon Clubley wrote:
>> 
>> The problems are not language specific and the problems are equally
>> the same on VMS regardless of language, including in C.
>> 
>> You can no more switch to using RMS in some transparent 64-bit mode
>> in C or Fortran than you can in Macro-32.
>
> Of course you can't.
>
> You can't on Unix either.
>

Oh yes you can.

> If you call Unix code compiled with 32 bit pointers with
> a 64 bit pointer or code compiled with 64 bit pointers with
> a 32 bit pointer then it will fail.
>
> The pointer size is part of the binary API.
>

And this kind of thing is taken care of for you automatically by
Unix (at least it is on Linux).

Calls to fread() (for example) work just fine from both 32-bit mode
and 64-bit mode without any source code changes required, unlike
with RMS.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
Walking destinations on a map are further away than they appear.