[Info-vax] VAX VMS going forward

[John Reagan]

On Thursday, July 30, 2020 at 8:42:09 PM UTC-4, Stephen Hoffman wrote:
> On 2020-07-30 21:18:29 +0000, Mark Berryman said:
> 
> > On 7/30/20 2:39 PM, Stephen Hoffman wrote:
> >> On 2020-07-30 20:13:36 +0000, Mark Berryman said:
> >> 
> >>> In conclusion, while there is certainly still some work to be done, I 
> >>> don't think it is that onerous to write a 64-bit app in current VMS.
> >> 
> >> That's 32-bit/P0 code (technically ~30-bit) with 64-bit/P2 data. Which 
> >> wasn't too bad to create, as was mentioned. This if you have all of 
> >> your dependencies capable of 64-bit/P2 references.
> > 
> > Flashback to my RSX days when I could run/write "really big programs" 
> > because all of the system libraries were mapped in supervisor space...
> > 
> > Let's see, 30 bits is 1G, right?  I don't have executables on my 
> > systems that are anywhere near that size, but that doesn't include any 
> > sharable libraries they may link to.  Where are these loaded in current 
> > VMS?  Are they limited to P0 space?  If so, then yes, I can see 
> > situations where that could become a limiting factor.
> 
> It all has to fit in P0 space; the executable code.
> 

You can put code in P2 on Itanium from day-1.  You don't have to recompile or anything.  (Itanium C++ needs to be compiled with /POINTER=64).

$ HELP LINK /SEGMENT Qualifier
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