RE: Moving to RPGIV

Pete, the first thing I did was to use CVTRPGSRC to convert RPG-III apps I
had written and was fairly familiar with.  The biggest hurdle for me was the
D-specs, and I've been known to code a snippet of I-specs in RPG-III and
convert that just to see the equivalent in RPG-IV.  But note that many of
the newer advanced features of D-specs are not utilized by the converter
(OVERLAY comes to mind).

There isn't much that doesn't convert and these are typically some arcane
opcodes that no one uses anyway.

The conversion also does not change "X   ADD   Y    Z" statements to the
"Eval   z = x + y".  And there are some rules regarding overflow that cause
these otherwise identical statements to behave differently that you need to
learn about.  Today, none of my programs use MOVEx, Z-ADD, ADD, SUB, MULT,
DIV, Z-SUB opcodes.

Anyway, after you convert some programs, you'll see that there's really no
learning curve (especially since you're proficient in Java and C++), and
you'll see how the syntax between III and IV are different.

Moving ahead from just converting source, you'll find good information on
advanced -IV topics on this mailing list, and on several tech newsletters
(Club Tech comes to mind, there are others).  I keep the online IBM RPG-IV
Reference handy, as well as the "Who Knew You Could Do That With RPG-IV?"
redbook.  Bob Cozzi's book is, I think, considered the gold standard for a
commercial reference, but I have only browsed through others' copies.  You
should remember to use the archives as well.

Good luck, and welcome aboard!  ;-)

db