GDG file Access in REXX

Gay251319 · New User Joined: 17 Jun 2009 Posts: 57 Location: Kochi

Hi,

To Access the normal dataset we are using like

enrico-sorichetti · Posted: Fri Nov 25, 2011 6:34 pm

You are mixing up things...
the ALLOC and the DEFine

and You are also mixing up the EXECIO parameters

what has the QUEUED() have to do with the STEM construct
the two things are normally used separately !

start over and do one thing at the time

expat · Posted: Fri Nov 25, 2011 6:37 pm

Might help if you explained what you are trying to achieve

Gay251319 · New User Joined: 17 Jun 2009 Posts: 57 Location: Kochi

Hi,

I want to read the data from the dataset which is a GDG ..

Can you please help me for the same

Regards,
Gayathiri Ravi

dick scherrer · Posted: Mon Nov 28, 2011 11:24 am

Hello,

Gay251319 · New User Joined: 17 Jun 2009 Posts: 57 Location: Kochi

Hi,

To get the currrent version of the GDG I have tried this step ...

GDGDA = "****************************"
/*-- LIST ALL GDG ENTRIES FOR THIS DATASET. --*/
RECS= OUTTRAP(DATA.)
"LISTC ENT('"||GDGDA||"')"
RECS= OUTTRAP(OFF)

/*-- DETERMINE THE CURRENT GDG DATASET NAME --*/
TOT = DATA.0 -1
PARSE VAR DATA.TOT . . NAME
SAY 'DATASET==>' NAME

But to read the Datas from the current version of the GDG .. nomal read statement is not working,,, i.e ,,
"EXECIO * DISKR **** (STEM OUDATA. FINIS)"

So while serching thru some sites,, I get to know that I shld use QUEUE () parameter,,, As I am not having enough idea of the same,, Can anyone pls me for the same

expat · Posted: Mon Nov 28, 2011 1:12 pm

superk · Posted: Mon Nov 28, 2011 7:32 pm

Gayathiri, why aren't you just allocating the GDG as you normally would in your job that's using this REXX exec? Also, as an additional comment, reading the entire contents of a dataset into a stem variable is never a good idea unless you have some control over how much data is actually present.

Gay251319 · New User Joined: 17 Jun 2009 Posts: 57 Location: Kochi

Hi,

Thanks all for ur valuable help..

Hi Superk,

" why aren't you just allocating the GDG as you normally would in your job that's using this REXX exec"

Can you tell this more clearly as I couldnt get exactly what you are meaning..

I always want to read the contents the current version of the GDG and do some process,, How it is possible ??????????

superk · Posted: Wed Nov 30, 2011 10:16 am

Gayathiri, since I've been involved with this forum, there's been certain assumptions and standards applied here, which I know I've stated before. This forum is about REXX, not TSO or ISPF (there's a seperate forum for those). The assumption here is that the code is standard REXX and that it's running in batch or an environment outside of foreground TSO. If it's not, that fact needs to be clearly stated.

The REXX langauge, like most others, doesn't allocate the datasets. That function is left up to the operating system to manage. In that case, based on the basic assumptions of this forum, since you haven't stated otherwise, I have to presume that there is a job running your exec. In that job, you would use DD statements to refer to the Generation Data Set. That can be accomplished either by a relative definition:

//DDNAME DD DSN=TEST.GDG(0),DISP=SHR or something similar, which will give you the most current generation at that moment in time, or by using the explicit definition:

//DDNAME DD DSN=TEST.GDG.G0001V00,DISP=SHR or something similar.

For a process running outside of the batch environment, dealing with GDG's gets to be trickier. The TSO/E ALLOCATE command can only work with an explicit definition of a GDG. For these environments, if relative allocation of a GDG is required, then I've found that the BPXWDYN dynamic allocation routine can mamage these allocations. I created a topic on this:

www.ibmmainframes.com/viewtopic.php?t=24474

to describe my experience with this function.

Gay251319 · New User Joined: 17 Jun 2009 Posts: 57 Location: Kochi

Hi All,

Thanks a Lot for ur valuable solution

rohanthengal · Posted: Thu Dec 08, 2011 10:30 am

i have a similar problem:
i want to check the list of datasets if they are existing through REXX EXEC.
I am able to do this task for NON GDG datsets using below code:

Bill Woodger · Posted: Thu Dec 08, 2011 1:25 pm

So you should have started a new, similar, tiopic, with a link to this one if you felt the content is relevant (that's with the URL button).

expat · Posted: Thu Dec 08, 2011 1:30 pm

There is my code in the above post, Kevin has given a link to his code, and here you are asking how it's done