External File Format

I have a dual format physical file without any DDS internal to the file.  I do 
have
two physical files with DDS that are the formats of the records inside the file.

Now, I want to open up my dual format physcial using the data structure in one
of the other physcial files with the data structure.

So far, I have figured out I need to do:

D File_DS                E DS       ExtName(ARFileCR)
D                                            Based(File_DS@)
D File_DS@                       *

Okay, so now I have a pointer, File_DS@ and a data structure associated with it.

Looking in the RPG manual I can't quite figure out though how to use it.

I am guessing I can open the file as a UP  F  (Update Primary, program 
described),
and be able to use the cycle.  But, how do I get my File_DS@ pointer to point 
to the
start of the record?

I tried this, and tried Eval  File_DS = %Addr(ARFile) but got a severity 20 
error,
RNF0341 The parameter for %ADDR is not valid; %ADDR is ignored.
and yet another error severity 40 this time stating I need input specs for my 
program
described file.

Do I have to open up the file as USROPEN?  Or can I use the cycle (which I would
prefer in this case, even knowing some people don't like it)?  Do I open up the 
file as
F for program described?

Please help, or point me to a URL that tells me how to do it, or source code.

Thanks In Advance,

Jim Langston

+---
| This is the RPG/400 Mailing List!
| To submit a new message, send your mail to RPG400-L@midrange.com.
| To subscribe to this list send email to RPG400-L-SUB@midrange.com.
| To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---