Re: Program design to minimize record locks

You need to read it INTO the DS:

Free-Form Syntax: READ{(EN)} name {data-structure}

Michael Kirkpatrick
Western Dental Services, Inc.
Information Systems / System i Development
(
Phone:
(714) 571.3582
(
Toll free:
(800) 471.4444
7
Fax:
(714) 480.3001
*
Email:
mkirkpatrick@xxxxxxxxxxxxxxxxx
8
Web:
http://www.westerndental.com/





Pete Helgren <Pete@xxxxxxxxxx>
Sent by: rpg400-l-bounces@xxxxxxxxxxxx
07/19/2007 01:34 PM
Please respond to
RPG programming on the AS400 / iSeries <rpg400-l@xxxxxxxxxxxx>


To
RPG programming on the AS400 / iSeries <rpg400-l@xxxxxxxxxxxx>
cc

Subject
Re: Program design to minimize record locks






If I am not careful, I'll start chasing my tail.....

After your original suggestion Booth, I had the following:

F spec:
FPMYFILE UF A E K DISK RENAME(FMYFILE:FILE01)

D Spec:
DFileNameDS E ds extname(FILE01)

And remember my original concern that the RENAME in the F spec might
bugger things but was needed since the /Copy "generic" I/O piece used
FILE01 as the reference so in order for this model/template program to
work, I needed to leave the name FILE01 alone in the /Copy member.

That wouldn't compile and Scott suggested that it wouldn't work because
the file name FILE01 really isn't an external physical file it is a
"placeholder" name used in the /Copy member. Scott suggested that I use
LikeRec which I DID use and it would compile. However, the data
structure FileNameDS contains no data after a read on the physical file
as I expected. So I may be stuck here.

Extname won't compile. Likerec compiles but I end up with no data in
the data structure.

Ideas?

Pete


Booth Martin wrote:

hmmmm.... I wonder if changing the LIKEREC back to EXTNAME might work?
You do need the "e" - I'd forgotten that in the example.

Pete Helgren wrote:

OK! So the compile works but the I am not getting what I expected

(maybe

this IS harder than I thought).

Based on the prior posts from Booth, I thought I understood that the D
spec for the data structure would hold a copy of the data read from the

file "automagically". He said "The FileNameDS does in fact always have

the most recently read data values, whether from the original read(n),
the screen exfmt, or the locking read." So either I misunderstood or I

am doing something wrong (that wouldn't surprise me).

Booth suggested the following:

D FileNameDS ds extname(Filename)
D OrigData s like(FileNameDS)
D NewData s like(FileNameDS)



This wouldn't compile until I changed the extname to likerec (and I had

to add an "e" for externally described). I assumed that a read on
Filename would automatically populate FileNameDS but that isn't the
case. A read on Filename puts no data into FileNameDS. So I
misunderstood or did it wrong.

Pete


Pete Helgren wrote:

Got it! I appreciate the clarification. It compiles now.

Thanks,

Pete


Scott Klement wrote:

Pete Helgren wrote:

A little wrinkle here:
The compiler seems unhappy with the fact that I have the RENAME

File spec has:

FPMYFILE UF A E K DISK RENAME(FMYFILE:FILE01)
DFileNameDS E ds extname(FILE01)

Did you mean to use LIKEREC?

A data structure defined with EXTNAME has absolutely no relationship
with the F-spec. Instead, you tell EXTNAME the external name of a

file,

and it looks for it on disk to get the fields. Since the argument

for

EXTNAME is a FILE NAME (not a record format name) and it's looking
directly at the file (not at the F-spec) I wonder if you really meant

to

use LIKEREC?

LIKEREC defines a structure to be like a record format that you've
defined on an F-spec. So you could say

DFileNameDs ds likerec(FILE01:*input)

And that would work, because it's argument is the RECORD FORMAT NAME
(which is what you renamed) and it's looking at your F-spec rather

than

directly looking at the file.