Re: Multiple Procedure during file read

[Barbara Morris <bmorris@xxxxxxxxxx>]

David Rittenberg wrote:
> ...,
> Also if you could please tell if what I am doing in the first place is
> right
> or wrong because I am executing
>
>              READ                                      filename
>
> in module M1 main procedure and accessing the file fields in the
> procedure P1 of module M2 by calling P1 immediately after the READ.
>

In RPG, doing a READ copies data from the input buffer to fields in the
module.  If you declare the file in another module, the fields in that
module won't be affected by the READ even if you have an override to
share the file.

If you want the results of the READ to be available to another module,
you have a couple of choices:

1. Pass each field as a parameter on your call to P1
2. Declare an externally-described data structure for your file in
module M1, and pass the data structure as a single parameter to P1.
(Declaring an externally-described DS causes the READ to copy the data
into the DS subfields.)

I would use #2:

Module M1:

Fmyfile  if   e      disk
D myfileData  e ds       extname(myfile)
 * If you use PREFIX on your F spec, be sure to use
 * the same PREFIX on your E-DS.
c         read    myfile
c         callp   p1 (myfileData)

Module M2:

P p1            b       export
D p1            pi
D  dataParm              like(fileData)
D fileData    e ds       extname(myfile)
D                        based(pFileData)
c        eval   pFileData = %addr(dataParm)
... now you can use the fields in the DS/file
P p1            e

If you are on V5R1, you can avoid the pointer stuff by using LIKEDS:

D fileData    e ds       extname(myfile)
P p1            b       export
D p1            pi
D  fileData              likeds(fileData)
... now you can use the fields in the DS/file
... by coding fileData.fld1 etc
c         if fileData.fld1 <> *blanks
P p1            e