[Info-vax] Hard links on VMS ODS5 disks

[Phil Howell]

On Wednesday, 23 August 2023 at 10:35:40 pm UTC+10, Simon Clubley wrote:
> On 2023-08-22, Arne Vajhøj <ar... at vajhoej.dk> wrote: 
> > 
> > VAX + VMS Eclipse MV + AOS/VS 
> > --------- ------------------- 
> > 
> > CISC CISC 
> > 32 bit virtual byte addresses 31 bit virtual word addresses 
> > 4 GB address space 4 GB address space 
> > 512 byte pages 2 KB pages 
> > 16 bit compatibility mode 16 bit compatibility mode 
> > 4 modes: 8 modes: 
> > K (0) - VMS 0 - kernel 
> > E (1) - RMS & Rdb 1 - virtual adress translation 
> > S (2) - DCL 2 - unused 
> > U (3) - application 3 - IO buffering & compatibility 
> > 4 - DG database 
> > 5 - Oracle database 
> > 6 - available for large 
> > applications 
> > 7 - applications 
> > memory organized: memory organized in 512 MB 
> > segments one per mode 
> > P0 - heap 
> > P1 - stack 
> > S0 - OS 
> > S1 - unused (early VMS) 
> > processes processes + threads (called tasks) 
> > kernel in Macro-32 or Bliss kernel in assembler 
> > utilities in Macro-32 or Bliss or HLL utilities in Algol dialect 
> >
> Based purely on what you write above, the use of an Algol dialect for 
> writing their userland code is a _massive_ win over the DEC approach 
> and _far_ superior to the way DEC did things. 
> 
> Wish DEC had done the same.
> Simon.

Off topic a bit, but we had already left the original topic.
 
I used to work for NCR in the 1970s on their I-series machines,
these were minis that would compete with the VAX when it came out (1977)
as well as with Burroughs Univac and IBM and some others (DG HP)
All the OS and utilities were written in a block structured ALGOL-like language,
When a machine was installed at a customer site, one of the first things to do
was to run a sysgen, which compiled and linked all this to build a system image to run,
this was then saved to disk for subsequent use.
This in-house language  was strictly for use only by systems programmers in
head office, and not released (AFAIK), but the resultant systems proved very reliable.
But then DEC in the 1980s was way more successful than NCR or DG anyway...

Phil