Prompt User From a pgplsql Function

Greetings List,

I am working on converting a large set of code from a commercial 4gl known as
Progress to plpgsql. This code defines a rating system for a transportation
logistics package. In the Progress world, one is able to prompt the user for
input during the execution of a trigger or a function, right in the middle of
a transaction. During the rating process, I have a couple of situations where
I need to prompt the user for a value that lies within an acceptable range
defined in the rating matrix. The front end to this application is X-Windows
written in C. All this rating (termed AutoRating) desperately needs to be
accomplished in plpgsql due to the complexity of the record look up and
record inserts. Is there any way to gather input from a user while in the
middle of a transaction from a plpgsql function? I think the answer is no;
but, maybe some you wizards have worked this magic before, or maybe, I've
been working at this way too long and have missed the obvious.

Any input and/or advice would be greatly appreciated.

Thanks...
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