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

[David Froble]

Simon Clubley wrote:
> On 2017-07-11, mcleanjoh at gmail.com <mcleanjoh at gmail.com> wrote:
>> I don't see it as an either-or situation.  I just see structures and copies
>> of multiple contiguous items out of their internal data structures as being
>> helpful to users and to VMS.
>>
> 
> And breaking binary compatibility for any existing images in the process
> whenever any minor change takes place unless you keep _all_ the previous
> versions of this internal structure around.
> 
> Simon.
> 

Which can also be a problem.  Say you're still using the old stuff to get, say, 
Username, and VSI increases the size of the Username data.  You can't get it 
without using the new access method.

Just bust the compatibility, in such cases, which can be rather rare.