Re: Did anybody ever use halt indicators?

On Sat, 5 Dec 2020 at 07:44, Jerry Adams <midrange@xxxxxxxx> wrote:

That brought back memories, Buck - both good and traumatic.

I kept the front panel of the last System/3 that we owned.
It was being shipped to the scrapyard.

Part of the problem, as I remembered it, is that if you turned on, say, H1
in one cycle it did not rear its head until the beginning of the next
detailed part of the cycle. Maybe RPG IV is different so I wrote a very
simple program to find out.

Right. Halt indicators did not stop the program at the instant they
turned on; the program continued on until the end of the detail cycle
and then halted. It pretty much had to work that way, because that's
how the input cards ended in the output stacker :-) The machine would
halt and you would know what record(s) caused the error by looking at
the last cards in the stacker. One assumes that for reasons of
backward compatibility, this behaviour was never changed through all
the years and all the versions of the RPG language.

I think that the most ancient remnants of RPG are all related to the
cycle: Primary files :-), Matching Record (Primary and Secondary
files), and Halt indicators. Honourable mention: Field Record Relation
indicators.

--buck