LRECL for GDG model

Arun Raj · Posted: Sat Mar 08, 2008 10:57 am

Hi,

I have a GDG model defined with the following attributes.

Organization : PS
Record format : U
Record length : 0
Block size : 0
1st extent tracks : 0
Secondary tracks : 0

When I am trying to create a new generatiion specifying this GDG model
in DCB without giving the LRECL, it is assuming the record length from the FD statement.

Could anybody explain how this is happening?

Thanks,
Arun

expat · Posted: Sat Mar 08, 2008 1:13 pm

You do not need a GDG model if your DFSMS configuration is set up correctly. If you can run without one, then do so, it just cuts aout another area for confusion.

Arun Raj · Posted: Sat Mar 08, 2008 1:59 pm

Hi Expat,

Yes it is good to see that I can execute any program by providing the GDG model and not any other DCB parameters.

But my doubt is , how it is getting linked with the record length given in the program?

Thanks,
Arun

enrico-sorichetti · Posted: Sat Mar 08, 2008 2:03 pm

You got it the other way around

in a[n] SMS environment the model dcb is not needed !

the issue of getting the lrecl from Your cobol FD is not GDG related

for any dataset opened in output mode if the dcb info is not specified for the dataset when allocating it ,
than that info will be taken from the program FD

Arun Raj · Posted: Sat Mar 08, 2008 3:27 pm

Thanks for the info. Yes, even if I omit the DCB, it is taking from the COBOL program FD as ours is an SMS environment. Does it work the same way for an eazytrieve program?

Can you please provide any link so that I could read more details on this.

Thanks,
Arun

enrico-sorichetti · Posted: Sat Mar 08, 2008 4:53 pm

let' s make a general point..
whenever a dataset is allocated without the dcb info,
the missing information will be taken from the DCB used to open that dataset
if input will be used and that' all,
if output that info will be stored in the VTOC entry for the dataset for further use

so the language used for the program is ... irrelevant
it could be cobol, pl/i, assembler, anything which opens the dataset with the correct dcb info

it does not matter whether the dataset is sms managed or not
whether the dataset is a GDG generation or not

the issue about model dscb is related only to GDG' s in a non SMS environment

expat · Posted: Sat Mar 08, 2008 5:07 pm

Arun Raj · Posted: Sun Mar 09, 2008 6:57 am

Enrico/expat

Thanks a lot for your response.

Could you please provide me any manual having all these information.

Thanks,
Arun

enrico-sorichetti · Posted: Sun Mar 09, 2008 10:02 pm

http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/DGT1D411/CCONTENTS?SHELF=DGT1BK33&DN=SC26-7339-01&DT=20001014144419

and then

http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/dgt1d411/3.2.2.1?ACTION=MATCHES&REQUEST=dcb&TYPE=FUZZY&SHELF=DGT1BK33&DT=20001014144419&CASE=&searchTopic=TOPIC&searchText=TEXT&searchIndex=INDEX&rank=RANK&ScrollTOP=FIRSTHIT#FIRSTHIT