[Info-vax] VAX VMS going forward

[Stephen Hoffman]

On 2020-08-01 16:49:00 +0000, John Dallman said:

> In article <rg3s7l$jrl$1 at dont-email.me>, craigberry at nospam.mac.com (Craig
> A. Berry) wrote:
> 
>> You have to control the pointer size of the relevant sections of code 
>> with #pragma pointer_size.  Documentation appears to be  scattered 
>> among the compiler docs, the CRTL docs, the programming  concepts 
>> manual, and the guide to 64-bit addressing.  Here's an old Digital 
>> Technical Journal article with some of the background:

Ayup. The current 64-bit doc is definitely chaotic.  Whole swathes are 
just missing entirely, particularly around security and networking and 
authentication, past the era the security manual was written for.

> OK, I understand better now. There's an important detail of #pragma 
> pointer_size, in that it affects declarations made in its scope, and 
> the effects persist when the pragma is out of scope. Many compilers use 
> pragmas for more direct effects on code generation, and the 
> higher-level effect of this one confused me at first.

SDL can generate some example pragmas, or have a look at the system 
pragmas (many of which are SDL-generated).

There's a save (push) and restore (pop) pragma block around most 
includes, for instance.

This both akin to what #import is used for on some platforms, and to 
isolate the local usage.


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