[Info-vax] DCL Syntax

[Arne Vajhøj]

On 8/30/2018 7:21 AM, Craig A. Berry wrote:
> On 8/29/18 9:04 PM, Arne Vajhøj wrote:
>> On 8/29/2018 9:54 PM, Craig A. Berry wrote:
>>> On 8/29/18 5:46 PM, Arne Vajhøj wrote:
>>>> On 8/29/2018 2:45 PM, Bill Gunshannon wrote:
>>>>> On 08/29/2018 02:33 PM, Stephen Hoffman wrote:
>>>>>> On 2018-08-28 18:54:54 +0000, John Reagan said:
>>>>>>> You need the /TREE qualifier for DELETE to match the behavior. 
>>>>>>> (Personally, it should have been /RECURSIVE and not /TREE but 
>>>>>>> nobody asked me)
>>>>>>
>>>>>> The use of /TREE was likely related to one of the more common 
>>>>>> tools used for this purpose: DELTREE.
>>>>>>
>>>>>> And yes, /RECURSIVE would likely have been a better and more 
>>>>>> obvious choice here.
>>>>>>
>>>>>> You and the other folks at VSI are also in a position to do 
>>>>>> something about that and about other DCL syntax, too.
>>>>>
>>>>> Yes, but considering the potential impact on existing already
>>>>> written procedures is it worth making little cosmetic changes
>>>>> like this when everyone (even me) understood the old meaning?
>>>>
>>>> Add /RECURSIVE, document /RECURSIVE, remove /TREE from documentation
>>>> but keep /TREE working.
>>>
>>> No one with any sense would use anything except MCR DFU DELETE/TREE for
>>> this purpose; it's massively faster than the DELETE/TREE implemented by
>>> HPE. Most likely the prior art of DFU and the rmtree() functions in
>>> Perl, Python and elsewhere influenced the choice of the /TREE qualifier.
>>> I for one would never have imagined or guessed /RECURSIVE, but I might
>>> have eventually read the documentation and eventually remembered that on
>>> VMS it's different just for the sake of being different. And then gone
>>> back to using the better, non-standard tools.
>>
>> Given that *nix uses -r or -R then I guess a few people would have
>> guessed.
> 
> But where *nix uses -r or -R, VMS just uses recursive filespecs. Where
> you would say grep -R on Unix, you don't say SEARCH/RECURSIVE on VMS --
> just SEARCH [...].

My guess is that <95% of VMS users also do multiple DELETE [...].

But somebody decided to add that qualifier at some point in time.

It may also be a matter of the users background.

Non IT-people may find tree much more natural than recursive
and may not know anything about *nix.

But IT people would know about recursive and they very
likely have some *nix exposure.

And I woudl expect most people using a DCL prompt today
to be in the second category.

Arne