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How can we Concatenate different generations of GDG

PostPosted: Sun Aug 01, 2010 5:42 pm
by maxcc
How can we Concatenate different generations of a GDG then copy it to a PS?

Re: How can we Concatenate different generations of GDG

PostPosted: Sun Aug 01, 2010 6:20 pm
by MrSpock
Not sure I follow. Concatenation is concatenation, it doesn't matter if they're GDG's or not. All that really matters is that they meet the system requirements for concatenation (if they're FB then they need to be of the same LRECL/BLKSIZE, if they're VB the largest LRECL has to be first).

Re: How can we Concatenate different generations of GDG

PostPosted: Sun Aug 01, 2010 9:01 pm
by NicC
Are your GDG datasets physical sequetial (PS) files or some other format?

Re: How can we Concatenate different generations of GDG

PostPosted: Wed Aug 04, 2010 11:53 pm
by maxcc
Physical Sequential(PS).

Re: How can we Concatenate different generations of GDG

PostPosted: Thu Aug 05, 2010 12:00 am
by MrSpock
Of course they're Physical Sequential, they're GDG's (they're either going to be PS or PO).

Once again, what's the real question? What's prompted this topic?

Re: How can we Concatenate different generations of GDG

PostPosted: Thu Aug 05, 2010 12:26 am
by NicC
I am not sure if, for example, an ADRDSSU dump would be regarded as PS? OK, it is not VSAM but does it have its own DSORG? I've really never tried to browse such a dataset in 35+ years.

Re: How can we Concatenate different generations of GDG

PostPosted: Thu Aug 05, 2010 12:35 am
by Robert Sample
Nic: ADRDSSU is its own animal. There are explicit warnings in the manual against using anything but the COPYDUMP verb of ADRDSSU to copy dump files. They mean it -- I needed to move one to another machine once and wound up having to ship the tape I made using COPYDUMP; nothing else I tried worked.

Re: How can we Concatenate different generations of GDG

PostPosted: Thu Aug 05, 2010 12:40 am
by NicC
So a GDG is not necessarily a PS file is the point. And I certainly would not try and copy a dump file although I believe that IEBGENER may work (but I would not trust it!).

Re: How can we Concatenate different generations of GDG

PostPosted: Thu Aug 05, 2010 6:27 am
by steve-myers
I've always been aware of the copy issue for DSS dumps, but I always assumed it's because the track images on the tapes can be greater than 32K bytes when the original DASD was a 3380 or a 3390. Mind you I don't know this to be a fact since I never really directly researched this matter, but this would cause problems for "normal" data set copies, but it would not be an issue for a custom written EXCP based COPYDUMP command in DSS itself or a custom written COPYDUMP utility.

Now here we've gone and "hijcked" another thread for something completely unrelated to the thread. Concatenating DSS dump GDGs seems to me to be the height of foolishness.

In theory you can have a PDS be a member of a GDG, but this seems to me to be kind of dumb. How would one specify a member of one in JCL? For that matter, will JCL accept something like this?
//NEWGDG   DD  DISP=(,CATLG),UNIT=SYSDA,SPACE=(TRK,(1,1,1)),
//             DCB=A.MODEL,DSN=GDGBASE(+1)
The explicit A.MODEL DSCB dataset is a PDS. I've never actually tried anything like this. I have to admit I'm too lazy to try it, but I'd be sort of curious to know if anyone actually does something like this!

Re: How can we Concatenate different generations of GDG

PostPosted: Thu Aug 05, 2010 12:11 pm
by smita257
Hi Maxcc,
Once, we had a requirement, to concatenate few files for our cobol program.
//STEP0010   EXEC  PGM=COBOL
//MORTGAGE DD DSN=.....FILE1,DISP=SHR
//                  DD DSN=.....FILE2,DISP=SHR
//                  DD DSN=.....FILE3,DISP=SHR

In this case, COBOL program READS mortgage file-file1,file2,file3 as one file.In sequential read, the first record will be from file1 and end-of-file condition will be arrived at the end of File3.
For your, GDG versions I think you can also use the same for concatenation.
//ddname  dd dsn=---.G0001V01,
//             dd dsn=---.G0002V02,
//             dd dsn=---.G0003V03

For Copying purpose, IEBGENER may help.
I just thought to share my idea, with my limited knowledge.You can just try, whether this works for ur requirement.Otherwise there are experts to help you.:-)
Thanks.