× The internal search function is temporarily non-functional. The current search engine is no longer viable and we are researching alternatives.
As a stop gap measure, we are using Google's custom search engine service.
If you know of an easy to use, open source, search engine ... please contact support@midrange.com.



In case your old program writes records, it will write blanks in the new
fields. That will cause problems for packed fields.

On Fri, Jan 29, 2021 at 10:38 AM Vernon Hamberg <vhamberg@xxxxxxxxxxxxxxx>
wrote:

Hi Dave

I'll jump in where angels fear to tread, perhaps.

Your program knows nothing about the new fields - it uses a buffer that
contains only the other fields it already knows about.

My understanding is, the data in the new fields is not brought into
memory in any meaningful way - your program won't change them even by
accident.

Now does the new program use those fields? Probably not. I think there
will be no ill effects.

Now although I generally support checking the format level, as we use
SQL more and more, that becomes less used - SQL functions know nothing
about format level checks.

Anyhow, I'm happy to be found incorrect. Learning happens every day, I
hope.

Cheers
Vern

On 1/29/2021 7:11 AM, Dave wrote:
Hi,



I was rather surprised to discover that in my current shop, it is a
regular
practice to use files in this way, thus avoiding (sometimes) the need to
recompile some of the programs sources where they are declared.

I’ve just modified such a file, placing a couple of new fields at the end
of the DDS. The program seems to function normally. But what happens
exactly when the program reads the file ? Surely, the memory pointing to
the new data somewhere is modified. Where is it and how can one be sure
there can be no ill effects ?



Thanks !

--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: https://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxxxxxxxx
Before posting, please take a moment to review the archives
at https://archive.midrange.com/midrange-l.

Please contact support@xxxxxxxxxxxxxxxxxxxx for any subscription related
questions.

Help support midrange.com by shopping at amazon.com with our affiliate
link: https://amazon.midrange.com


As an Amazon Associate we earn from qualifying purchases.

This thread ...

Follow-Ups:
Replies:

Follow On AppleNews
Return to Archive home page | Return to MIDRANGE.COM home page

This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact [javascript protected email address].

Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.