[Info-vax] Access to _all_ VMS system services and library functions from DCL ?

[Jan-Erik Soderholm]

Den 2017-07-12 kl. 14:56, skrev Simon Clubley:
> On 2017-07-12, David Froble <davef at tsoft-inc.com> wrote:
>> Simon Clubley wrote:
>>> On 2017-07-11, David Froble <davef at tsoft-inc.com> wrote:
>>>> Simon Clubley wrote:
>>>>>>
>>>>> A single block of data which is directly accessed is too limiting and
>>>>> will cause massive maintainence problems as structures are changed and
>>>>> field sizes changed in the future.
>>>> Why?
>>>>
>>>
>>> Because existing binaries will now be looking at the wrong locations
>>> for the data items they need.
>>
>> Not if the system service rejects an improper data block.
>>
> 
> Erm, in your scheme, it's the _output_ from the system service which
> will have changed format, not the input.

And beside, in a strictly OO world, you would access the output
data using named keys, so the format of the returned data block
is of no importance. If we are (still) talking about DCL, the
actuall version of DCL used will follow the version of OpenVMS
anyway, so there is no incompatibility.