Re: RPG runtime

Seems to me that if there had been an EXIT opcode, it would still be there. But I just found an RPG II reference manual on bitsavers - the EXIT opcode is there, and, yes, it is for transferring control to an assembler language subroutine. System 34 days!

I'm glad I don't have to have THAT much fun these days!

Regards
Vern

On 4/19/2021 2:31 AM, Gad Miron wrote:

I vaguely remember that RPG II had an EXIT Op Code you could use to call

external
(Assembly?) Subroutines. used that for sorting or conversions me think.

Gad

date: Sun, 18 Apr 2021 10:32:24 +1000
from: Frank Kolmann <Frank.Kolmann@xxxxxxxxx>
subject: RPG runtime (was Upcoming spring 2021 RPG enhancements)

RPG evolved from a very simple language. I was stunned when I found in
RPG II one could add only 2 variables together in one line of cpde.
RPG II III IV never had a concept of functions that you could import
into your code.
There were no standard or other librarys one could access.
All I/O functions and op codes were built in for want of a better term ,
( is that? runtime?)
There was some ability to code SPECIAL routines defined on the F (file)
specs but hardly no one knew how to do that.
To compare RPG to C is not imo a comparison that makes sense.
With C one has capabilities to code compilers and operating systems.?
RPG never had that.
RPG was perfect for coding solutions to business requirements.
I found C was a bit like using a military tank to go to your local
shops, way to much overkill to solve business issues.
I found simply getting C code to compile was next to impossible.
I could not write C code like I wrote RPG.? I could code an entire RPG
program then use the compiler to flush out coding errors.
With C I needed to start with a very small bit of C code that compiled,
then add a line or two and compile that.
It was the only way I could construct a C program , I needed hundred or
even thousands of compilations.
Luckily todays C compilers are very fast so C coding in that manner was
feasible.
When you throw OOP into the ring RPG never had that.
Only relatively recently did RPG ILE even have a concept of functions.
It was only when I learnt C did I begin to understand what functions
were, what library functions were etc.
I am old and retired from coding but I wonder, do we really need to
convert RPG from a family car into a military tank.

Frank