Back in the good old days when we were using a S/36, we had occasion to use some CRT files in our RPG II programs. Not often, but sometimes. At times, we would allow the program to put out a few lines on the screen and then prompt via a KEYBORD file, and sometimes we would let the data run up the screen until end-of-file condition was reached.

In migrating one of these programs to the AS/400, we encountered a strange problem: the data was appearing only on the bottom line of the screen, instead of filling up the whole screen. The two programs (one running in S/36E on the AS/400 and the other running on a S/36) were identical. I checked the IBM manual S/36 Compatible RPG User's Guide and Reference and found its three-page section, "Using a CRT File," was virtually identical to the chapter in the original S/36 manual. There was no clue that a change had been made.

Regarding column 18 of the O-specs (line after), both manuals say that it "can contain a number from 0 to 3" without saying what happens if you leave that column blank. A blank in that column on the S/36 is interpreted as meaning "1" and the data rolls up the screen nicely. A blank in the same column in the S/36E of the AS/400 means "0" and the data sits on the bottom of the screen, without moving.

Why didn't IBM inform us of this difference?