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

[Stephen Hoffman]

On 2022-09-10 23:35:06 +0000, alanfe... at gmail.com said:

> I recall Hoff once lamenting about logical names. He said they are 
> mostly good for I/O redirection. And, IIRC, not liking using them to 
> store application data.
> 
> I was wondering how people here (esp. Hoff!) feel about their use in 
> batch queues and mail.

The use of logical names within batch and mail... for what?

The OpenVMS mail app, batch-print for process control and scheduling, 
and logical names as a volatile and exceedingly limited key-value 
store, sure, if you're in the previous millennium, or have never met a 
more modern app configuration data storage API.

There's no good alternative for I/O redirection on OpenVMS, which also 
happens with email addresses and mail, and with batch-print and such. 
Which where I'll usually use logical names.

There are better alternatives for app configuration data, and for 
key-value stores. Unfortunately, OpenVMS forces app developers to write 
their own here, past some DECwindows stuff and ilk, and probably tools 
in Perl, Python, and Java, etc.

Not great, but more workable, less disjoint, app-local, and decidedly 
less volatile: 
https://developer.apple.com/documentation/foundation/preferences

Look at the OpenVMS C and Java run-time configuration logical names for 
some of how storing configuration data becomes problematic.

Using and parsing logical names to read configuration data is something 
I've done... but really don't prefer doing.

Having your app settings and your redirections disjoint and scattered 
in files all over the place in a volatile and limited key-value store, 
and parsing user-provided input, just gets... tedious.

And there's no way to adapt to future changes compatibly with a bevy of 
logical names, given the lack of wildcards in the API. (This is a 
variation of how RMS files can grow in numbers. q.v. cluster 
configuration database. Which also uses logical names.)

OpenVMS lacks robust integration with LDAP and lacks robust app 
configuration data storage, and lacks robust process management and 
scheduling services, among other limits.

If you wanted a bad and volatile and file-disjoint ancestor of the 
Windows registry, or want to write lots of your own code, logical names 
absolutely do have you covered, of course.



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