On 9/14/2022 7:31 AM, Bob Gezelter wrote:
> On Tuesday, September 13, 2022 at 8:32:16 PM UTC-4, Arne Vajhøj
> wrote:
>> On 9/13/2022 3:58 AM, Marc Van Dyck wrote:
>>> 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$SYSTEM is of course not good practice, but
>>> desiging applications to use their own table(s), use rights ids
>>> to grant access to them, and connect automatically to the right
>>> tables at login time works perfectly for me. We also use such
>>> mechanisms for our development environment, so that each version
>>> of each application gets its own set of tables.
>> I am sure that it works.
>>
>> But it is very customized solution.
>>
>> It requires changes to users login.com if I understand it
>> correctly.
>>
>> And I don't think it makes things easily searchable (unless there
>> are a number of conventions everybody need to know).
>
> Separate per-product logical name tables are quite feasible, see my
> OpenVMS Technical Journal paper on Hierarchical Logical Names,
> "Inheritance Based Environments in Stand-alone OpenVMS Systems and
> OpenVMS Clusters (February 2004)" at
> http://www.rlgsc.com/publications/vmstechjournal/inheritance.html.
>
> As to LOGIN.COM, Marc's suggestion of SYS$MANAGER:SYLOGIN.COM works
> for global definitions. If one desires a more precision approach to
> manage individually authorized applications, or different versions of
> the same application, or for that matter, some mixture of both, one
> can straightforwardly implement a group-wide login.com, as described
> in "Group-wide LOGIN Profiles Lower Risk, Decrease Cost", the
> September 30, 2010 installment of The OpenVMS Consultant,
> http://www.rlgsc.com/blog/openvms-consultant/group-wide-login.html.
>
> When I used the rights identified approach at a client, I was dealing
> with a large collection of applications, and a far larger workforce,
> each with an individual login. Individuals had to be checked out on
> each application by a supervisor, and then granted access when a work
> order required them to use the application. In effect, their captive
> account screen menu would only show the applications they were
> cleared to work on that particular shift. Granting/revoking these
> identifiers was delegated to the section supervisors, who similarly
> had an application (DCL-implemented) to check-in/check-out batches of
> work. Tens of operators per shift; worked smoothly for years.
Sounds like some people are doing some pretty advanced stuff
with logicals.

:-)

Arne

On Wednesday, September 14, 2022 at 5:32:40 PM UTC-4, Jonathan wrote:
> ! The reason for the separate queue entry and buffer logicals:
> ! 1) The upper limit on a logical value is 255 bytes.
> ! 2) Buffers need to be larger than 255 bytes. The required
> ! larger buffers are implemented as logical arrays (search lists.)
> ! 3) Creating a logical array is not an atomic operation. A reader
> ! may see a partial array.

As far as I can tell from the ISD, replacing a logical name is an
atomic operation. A single LNMB is created with all the LNMX
blocks for the equivalence names embedded within it. Then
IPL is raised and the block is inserted in the table, possibly
deleting an existing block.

Usually the trouble you have is reading the name since you don't
know the max index ahead of time, creating a race condition
from multiple $TRNLNM calls.

In article <60a6807f-fbb7-400a-9f6a-fe452c3c5fc8n@googlegroups.com>,
"alanfe...@gmail.com" <alanfeldman48@gmail.com> writes:

> Greetings.
>
> 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.
>
> Just askin'.

I use logical names for many things, also I/O redirection, but that is
relatively minor. They really come into their own with cluster-wide
logical names. In particular, one can have, say, a logical name table
with access for a group but, due to the parent table, available
cluster-wide.

In article <4f5300c2-b306-43be-bf63-ece6052e3578n@googlegroups.com>,
abrsvc <dansabrservices@yahoo.com> writes:

> I have used them for creating separate environments for clients. Modifying
> the search order and adding application specific tables, using group level
> tables to create a complete environment separate from others, etc.

Yes, another great example.

In article <54860c09-5d3c-463a-bf92-860704d9700dn@googlegroups.com>,
"alanfe...@gmail.com" <alanfeldman48@gmail.com> writes:

> You can use logical names for recipients! I don't know if this is a true
> story, but someone did a=20
> $ DEFINE MORON <user-address>
> And when the person received it, it should that it was sent to MORON!

I think that one can also do DEFINE USERNAME OTHER_USER so mail sent to
USERNAME will go to OTHER_USER.

On Saturday, September 10, 2022 at 7:49:21 PM UTC-4, abrsvc wrote:
> On Saturday, September 10, 2022 at 7:35:08 PM UTC-4, alanfe...@gmail.com wrote:
> > Greetings.
> >
> > 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.
> >
> > Just askin'.
> I have used them for creating separate environments for clients. Modifying the search order and adding application specific tables, using group level tables to create a complete environment separate from others, etc. Gave a talk about this at a bootcamp once.
>
> I have seen logical names used as status strings, application "switches" and other things too.
>
> Many uses, some good, some not so much.
>
> Dan

I did the same c. 1999! I set up a test database for export experiments.

On Monday, September 12, 2022 at 4:40:49 PM UTC-4, Stephen Hoffman wrote:
> On 2022-09-12 18:18:09 +0000, alanfe...@gmail.com said:
>
> > You can use logical names for recipients!

[...]

> > I don't know if this is a true story, but someone did a$ DEFINE MORON
> > <user-address>
> > And when the person received it, it should that it was sent to MORON!
> You can do that with pretty much any mail tool, or with DNS translations, etc.
> > I suppose that's harmless enough for personal use. I suppose one could
> > make "public" logical names for positions like systems administrator,
> > or HR Head, who might change from time to time.
> Easier to use a forwarding entry in the database for forwarding
> arriving OpenVMS MAIL to a fixed address (and SYSTEM, FIELD, etc., are
> routinely forwarded on systems I have administered), but there are
> limits. OpenVMS MAIL doesn't like multiple forwarders. Forwarding to a
> forwarding server does work, as a workaround.

The MORON bit was an unintentional thing. The sender didn't know it would appear as "To: MORON" to the recipient. The sender must have assumed that MAIL would show the recipient the translation, not the actual logical name.

>
> MAIL really doesn't work all that well by current standards. When open
> and unsecured network connections are still permissible, MAIL does
> provides a way to send logs and notifications. Though there are other
> and more secure paths for that. I've used php and other tools to make
> secure connections, where the target SMTP is operating with modern
> settings and where security exceptions are discouraged.

The only time I use VMS MAIL is on EISNER, and it's always initiating by the system manager. I'm just curious about how people here feel about logical names, other than I/O direction.

[...]
> Pure Personal Opinion | HoffmanLabs LLC

Alan

In article <a881a1ce-5ba7-46f8-b093-13701014565bn@googlegroups.com>,
"alanfe...@gmail.com" <alanfeldman48@gmail.com> writes:

> On Monday, September 12, 2022 at 4:40:49 PM UTC-4, Stephen Hoffman wrote:
> > On 2022-09-12 18:18:09 +0000, alanfe...@gmail.com said:
> >
> > > You can use logical names for recipients!
>
> [...]
>
> > > I don't know if this is a true story, but someone did a$ DEFINE MORON
> > > <user-address>
> > > And when the person received it, it should that it was sent to MORON!
> > You can do that with pretty much any mail tool, or with DNS translations, etc.
> > > I suppose that's harmless enough for personal use. I suppose one could
> > > make "public" logical names for positions like systems administrator,
> > > or HR Head, who might change from time to time.
> > Easier to use a forwarding entry in the database for forwarding
> > arriving OpenVMS MAIL to a fixed address (and SYSTEM, FIELD, etc., are
> > routinely forwarded on systems I have administered), but there are
> > limits. OpenVMS MAIL doesn't like multiple forwarders. Forwarding to a
> > forwarding server does work, as a workaround.
>
> The MORON bit was an unintentional thing. The sender didn't know it
> would appear as "To: MORON" to the recipient. The sender must have
> assumed that MAIL would show the recipient the translation, not the
> actual logical name.

So were you the sender or the recipient? :-)

> The only time I use VMS MAIL is on EISNER

I've been using VMS MAIL for 30 years.

> I'm just curious about how people here feel about logical names, other
> than I/O direction.

I use them for all kinds of things. With the modes, tables, parent
tables, search lists, concealed devices, etc., they are really powerful.
Often a topic in the "why can't linux do this?" discussions. :-)