From back when I was in college and we had a S/360-30 running
our own "spooler" program, as I recall, ALC students were told to
*NOT* use EXCP to read the card reader unless they had informed
the operator before submitting their JOB. We were allowed to do
EXCP with tape. We were not to do this with DISK.
Relative to Cards, seems that by not using DTFCD, one could
bypass the spooler program (in house developed) and one could
read the JOBs for production and they wouldn't be seen by the
spooler. So those jobs wouldn't get run.
Dunno if this would be possible with today's VSE, but I mention
it in the case one could use this, or, an exit point with Power
(which I haven't touched for well over 20 years now).
Thought this might trigger some workable ideas.
--
Regards,
Steve Thompson
On 12/13/2025 5:31 PM, Paul Gilmartin wrote:
On 12/12/25 16:39, Charles Mills 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.
...
This appears to be discussing in-band delimiters,
not out-of-band, such as the operator's pressing
a button on the reader or a reflective spot on
tape.
In-band delimiters impel a duty to provide an escape
convention so the delimiter, however unlikely,
can appear as ordinary data.
Allowing alternate delimiters is unsatisfactory
because it requires the user to search by trial-and-error
for a string absent from the data.
