[Info-vax] CRTL and RMS vs SSIO

[Dave Froble]

On 10/8/2021 10:51 AM, Stephen Hoffman wrote:
> On 2021-10-07 21:03:53 +0000, Dave Froble said:
>
>> On 10/7/2021 1:01 PM, Stephen Hoffman wrote:
>>> On 2021-10-07 16:18:28 +0000, Dave Froble said:
>>>
>>>> I'm aware of how useful something like SSIO would be.  I'm just
>>>> appalled by the design and implementation.  As mentioned, it seems
>>>> aimed at just a few current uses, and totally ignores how useful it
>>>> would be for many more future uses.  This is rather consistent with
>>>> the long time apathy with which VMS has been treated.  It's more a
>>>> patch than an enhancement.   This is what I lament.
>>>
>>> Alas, there's no other outcome when upward-compatibility is an
>>> overarching goal for the platform.
>>
>> Now I''m just a dumb polock, wandered down out of the woods.  But I
>> just don't see where upward compatibility has anything to do with
>> enhancements to the DLM.  If existing calls continue to work as
>> before, and only when an optional extra parameter would enable new
>> capabilities, then upward compatibility just cannot be an issue.  At
>> least for this.
>
> I was building on the "long term apathy" and "more patch than
> enhancement" comments, with the increasing difficulties even making
> comparatively minor or isolated changes and updates.
>
> Larger changes can be Really Difficult with ~40 years of accumunated
> dependencies around, assuming the developers and schedule and funding
> are all available. (q.v. Hyrum's Law.)

Hyrum's Law and such points to the need of good software architecture. 
(I always have to use the spell checker on that word.)

If intelligent and structured use of something like VMS if followed, 
enhancements should not be much of an issue.  It is when people do 
things they really should not the problems arise.  Compatibility with 
well designed tools should not be an issue.  Going off on one's own, and 
making assumptions about things, which are not guaranteed to remain 
as-is is where such problems occur, for the most part.

As a simple example:

If Stat% and 1%

vs

If Stat% and SS$_NORMAL

That causes a problem, if the VMS developers decide that "1" is no 
longer what it used to be.  The problem is not compatibility, the 
problem is not using the approved constant.

Now while breaking customers code can be bad for business, the dumb 
polock can say "fuck 'em, enhance the product and break their erroneous 
code".

:-)

-- 
David Froble                       Tel: 724-529-0450
Dave Froble Enterprises, Inc.      E-Mail: davef at tsoft-inc.com
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