|
I don't think I can do much better than Mark's great explanation Jack.
The only thing I might mention is that the S/38 - IBM i paradigm of
interactive programming relies on an underlying OS feature - namely that
there is only ever one copy of the program instructions in memory and the
system always automagically handles _all_ of the memory for a user and
associates it with the program when needed. So state information (including
current file cursor positions etc.) is retained with _zero_ effort on the
part of the programmer.
S/34/36 MRT programmers had to actually decide which variables (including
of course current file positions) needed to be retained between messages
and on receipt of a new message they had to "page in" the appropriate set
of variables, reposition file cursors, etc. CICS is much the same except
that there is some built-in functionality to assist in the storage etc. of
state information. In both cases this programming had to be done without
the assistance of pinter-based dynamic memory - so making decisions about
which variables were to be retained was a major effort.
Jon P
On Aug 11, 2023, at 2:21 PM, Jack Woehr via MIDRANGE-L <midrange-l@xxxxxxxxxxxxxxxxxx> wrote:
wrote:
It might be interesting if you would expand on those remarks.
On Fri, Aug 11, 2023 at 12:19 PM Jon Paris <jon.paris@xxxxxxxxxxxxxx>
to
For anyone who has ever done S/36 MRT programming CICS is pretty simple.
For those who grew up on the S/38 / AS/400 with the "why should I have
waysworry about state information?) mentality it is much harder. In some
difficultyit is the same reason that programmers with that background have
thegetting their heads around web programming. S/36 MRT programmers find
listweb a breeze!
--
*JACK WOEHR, IBM Champion 2021-2023
<https://www.credly.com/users/jack-woehr/badges>*
*SENIOR IBM i ENGINEER*
303.847.8442
jwoehr@xxxxxxxxxxxxxxxxxxxxxxxx
<https://www.linkedin.com/in/jackwoehr/> stay connected
<https://www.linkedin.com/company/absolute-performance-inc./>
<https://www.absolute-performance.com/>
http://www.absolute-performance.com/
NON-DISCLOSURE NOTICE: This communication including any and all
attachments is for the intended recipient(s) only and may contain
confidential and privileged information. If you are not the intended
recipient of this communication, any disclosure, copying further
distribution or use of this communication is prohibited. If you received
this communication in error, please contact the sender and
delete/destroy all copies of this communication immediately.
--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing
To post a message email: MIDRANGE-L@xxxxxxxxxxxxxxxxxxrelated questions.
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
--
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.
--
As an Amazon Associate we earn from qualifying purchases.
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.