Re: READE EOF Handling/Repositioning

Patric,

Use PLIST to allow multiple keys to be used on file IO

Set up a PLIST with all the keys you need to position the file

Use a different PLIST with only the keys required for the READE or READPE

You can set the individual key fields used in the PLIST to *HIVAL or
*LOVAL or specific values as required.

Cheers

Don





From: "Patrik Schindler" <poc@xxxxxxxxxx>
To: "RPG programming on IBM i" <rpg400-l@xxxxxxxxxxxxxxxxxx>
Date: 05/03/2020 02:45 AM
Subject: Re: READE EOF Handling/Repositioning
Sent by: "RPG400-L" <rpg400-l-bounces@xxxxxxxxxxxxxxxxxx>



Hello Nick,

Am 04.03.2020 um 17:09 schrieb Nick <nicola.brion@xxxxxxxxxxxx>:

Wait. If you need to read from a *Specific* point inside the key, you

have to use 2 keys, one for setgt and one for the readp (or a single key
specifiying number of filed to use). If you just need to read all record
that have that key, just use a single one.

A 'classic' example with orders row:

Setgt (OrdNum) OrdRow
Readpe (OrdNum) OrdRow

will read all order's row for the given order, while:

Setgt (OrdNum:100) OrdRow
Readpe (OrdNum) OrdRow

will read from highest row less or equal 100, and then down to lower

one.

I don't think that works with V4R5 RPG, since there's no "free" and I
can't remember to have additional arguments for SETGT allowed. Yes, really
classic. :-)

Aside, the goal is after READE sets EOF, I want to to a SETGT on the last
record, so I can properly READPE backwards. READ(P)E should be done with
just one key field to only pick out the needed records, and set BOF/EOF
when this subset of records is exhausted. But for repositioning at EOF, I
need *HIVAL for a second order key. SETLL with just the first order key
already places me at BOF (for the given record set).

Niels brought me on the right track. :-)

:wq! PoC

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