Long ago, in a galaxy far away, I wrote tools for converting from
DOS to MVS.
One of the first tools I wrote, I did in COBOL so I could read
the ICCF backup tapes and I would scan the source looking for
problem code.... (and COBOL so who ever came behind me had a
chance to fix things...).
The data was actually in 80 byte format, but the ICCF backup, as
I recall, was "compressed".
Now, if a backup "tape" is available for this kind of thing the
REXX code would have to fit the LRECL=80 requirement, wouldn't
it? (Yes using an MVS concept while discussing DOS)
The question is, and I don't have any VSE manuals -- Did VSE ever
implement "DLM=" or some equivalent?
If not, your REXX code would have to start in CC=2 so you don't
confuse POWER (?). Or am I thoroughly lost?
If this is coming from CMS via a virtual card punch going to
"POWER", I think you will have to pre-process on the CMS side to
shift right 1 char, but then be sure you don't overflow or
truncate your code.
Similar thing if this is coming out of a library on the VSE system.
Regards,
Steve Thompson
On 12/14/2025 5:03 PM, David Clark wrote:
Note: I didn't use DTFDI because it restricts record length by device type
(80, in the case of SYSRDR/SYSIPT). REXX source lines can be longer than
80 so that is why I was using DTFCD.
Sincerely,
Dave Clark
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On Sun, Dec 14, 2025 at 4:57 PM David Clark <[email protected]> wrote:
Does DTFCP still exist?
I haven't heard of DTFCP. DTFDI gives device independence. The following
are all the DTFs I found on the system.
DTFCD
DTFCN
DTFDA
DTFDI
DTFDU
DTFIS
DTFMT
DTFPH
DTFPR
DTFSD
DTFSR
Sincerely,
Dave Clark
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int.ext: 91078
direct: (937) 531-6378
home: (937) 751-3300
Winsupply Group Services
3110 Kettering Boulevard
Dayton, Ohio 45439 USA
(937) 294-5331
On Fri, Dec 12, 2025 at 6:39 PM Charles Mills <[email protected]> wrote:
FWIW, Google AI sez
In IBM VSE, trying to read a sequential file (like a card reader input
stream) past the end-of-file (EOF) marker will result in an error or an
exception. You cannot "read past EOF" in the conventional sense of
retrieving more data, because no more data exists. The standard approach is
to detect the EOF condition and stop reading.
I recall doing something like this but it was literally 50 years ago.
The problem is complicated because there is no real card reader (I assume
:-/). When I did it there was a real 2540, but the program was actually
reading from POWER, not from the card reader. That ship had already sailed.
I have no experience with VSE in the post-card-reader era. How do you
submit the job? From CMS via a virtual card reader under VM?
Does DTFCP still exist? It was a badly-kept IBM secret that gave you DTF
device-independence, and more flexibility than any of the supported DTFxx
macros.
Charles
