[Info-vax] Use of logical names other than I/O redirection

[Dave Froble]

On 9/13/2022 4:23 PM, Stephen Hoffman wrote:
> On 2022-09-13 07:58:46 +0000, Marc Van Dyck said:
>
>> Arne Vajhøj has brought this to us :
>>
>>> 3) Logical names does not scale well. 50 fine, 100 fine, 200 fine but 100000
>>> does not work. Windows registry is a fine example of something that has
>>> become so big that it is difficult to find things.
>>>
>> Not if you use separate, dedicated logical name tables. Putting everything in
>> LNM$SYSTEM is of course not good practice, but desiging applications to use
>> their own table(s), use rights ids to grant access to them, and connect
>> automatically to the right tables at login time works perfectly for me. We
>> also use such mechanisms for our development environment, so that each version
>> of each application gets its own set of tables.
>
> That's kinda the definition of not scaling well.
>
> But as you have a small and self-contained environment with simple requirements,
> by all means logical names can and should be used.
>
> Again, my belief that logical names are a bad solution for configuration data
> and are just complex and convoluted and volatile and disjoint does not mean
> y'all shouldn't use them.

On that point I agree completely.  Tools can always be misused, ie; hammer and 
screw, screwdriver as prybar, and such.

But I have to ask, isn't the app configuration an issue for the app, not the 
environment?  I fail to see any logic in expecting an environment to provide 
generic tools for such activity.  Nor am I a big fan of "generic" in general.

> Logical names are what they are, and the available OpenVMS alternatives for app
> and system configuration data storage are lacking. Which is why logical names
> continue to get used. Later, rinse, repeat.

With a few logical names I can run many copies of an application on a single 
system.  That has always been valuable to me, though much less so in this era of 
cheap hardware and systems dedicated to single applications.

> It's also why we get messes such as the DEC C logical name thicket, and a more
> recent favorite of mine, and the ever-popular defaults-to-an-open-relay-whoopsie
> SMTP server database.

To me that is a nightmare.  What does the apps do if the logicals aren't set as 
needed?  Scary.

> OpenVMS doesn't do this app-local and app-isolated stuff at all well (which
> tracks back to other issues and errors and limits), though it is feasible to
> create a DSL with lib$table_parse, and it is possible to use LDAP (though not so
> well nor so easily, strictly locally), and various languages do have
> language-specific configuration storage mechanisms.

Have to ask, just what is LOGIN.COM?  I'd suggest it is the place for some 
configuration information, at least enough to get to a place where more details 
are specified.  Consider it an "ini" file for a process instead of for a single 
executable.


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