How to read a dynamically generated VOLSER as PARM

bvanilkumar · New User Joined: 23 Dec 2006 Posts: 10 Location: SYDNEY

Dear All,

I have a query related to VOLSER (Volume Serial) of a tape.

Situation : A dataset is archived to a tape where the VOLSER is dynamically generated. I need to retreive the VOLSER number and write into a VSAM file.

Questions:

1) How to define the 'VOLSER' parameter for dynamic allocation?
2) Is there any utility to get the VOLSER of a tape?
3) Can I pass the VOLSER to another step as PARM, so that a program can read the PARM and write into a VASM file.

Thank you
Regards

Anil

itzphaniz · New User Joined: 02 Sep 2005 Posts: 39

Buddy-

even i had similar requirement. Please go thru this link. hope it is of some help.

ibmmainframes.com/viewtopic.php?t=19300&highlight=

dick scherrer · Posted: Tue Apr 03, 2007 9:46 pm

Hello,

Is the archived file on a tape that is a collection of archives or is archived separately?

If it is archived separately, all you will need is to query the tape management system or do a LISTCAT to get the volser.

What will the entry in the vsam file be used for? Usually, volser info for an archive is not stored directly in an external file. What happens when the archive is rebuilt and the volser changes?

expat · Posted: Wed Apr 04, 2007 12:38 pm

What do you mean that the VOLSER is dynamically generated ? All that happens is that the job selects a scratch tape from the pool and uses that tape.

Do you know the DSN being generated by your job, and is it catalogued ? If so, you can easily get the VOLSER by a utility such as IDCAMS.

UmeySan · Posted: Wed Apr 04, 2007 1:40 pm

Hi bvanilkumar !

Just one hint to your Top-3

You could add a step with a little programm that only opens and closes this tape, you created one step before. This programm must be a little assembler-pgm which is using the RDJFCB macro for reading the internal JobFileControlBlock of the JCL. Then you can extract the actual informations for that file. Like DatasetName, VolSer and so on. By looking at IOJFCB-DSECT, you could see all the internal FieldDefinitions where the Informations are stored in and where you could get them from.

Regards, UmeySan

Example for coding. The infile here is declared and named KTONDCB and the DD in the JCL for that file is HUGO.

*
USING IOJFCB,R5
RDJFCB KTONDCB ...macro-call rdjfcb
*
L R5,=A(KTONFCB) ...INIT SYSTEM-BLOCK FCB
MVC KTONNAM(44),JFCBDSNM ...MOVE DATASET-NAME
MVC KTONMEM(08),JFCBELNM ...MOVE MEMBER-NAME

.... move the desired informations to a list-output ore store them
anywhere you want

DROP R5
*

File-Definition

SPACE
KTONDCB DCB DDNAME=HUGO,
DSORG=PS,MACRF=GL,EXLST=KTONLST
SPACE
SPACE
DS 0F
KTONNAM DC CL44' ' ...Area DATASET-NAME
KTONMEM DC CL08' ' ...Area MEMBER-NAME
KTONVLS DC CL01' ' ...Area Count of VOLUMES
KTONVOL DC CL30' ' ...Area VOUME-NUMBERS
SPACE
DS 0F
KTONLST DC X'87' ...EXLST FUER RDJFCB
DC AL3(KTONFCB) ...ADRESS FUER RDJFCB
SPACE
DS 0F
KTONFCB DS 176C ...RETURN-Area FUER RDJFCB
SPACE
PRINT ON,NOGEN

Definition for the RDJFCB

PRINT ON,GEN
SPACE
IOJFCB DSECT
IEFJFCBN LIST=YES
SPACE
PRINT ON,NOGEN

expat · Posted: Wed Apr 04, 2007 1:49 pm

UmeySan

Do you think it is a good idea for applications programmers to be chasing system control blocks, because I do not.

Don't forget that some applications programs need to be run from an APF authorised library. I shudder to think the damage a mis coded instruction may cause.

What is wrong with using the catalog structure to record the details of the tape and its use, from which the information can so easily be found and subsequently used.

UmeySan · Posted: Wed Apr 04, 2007 2:26 pm

Hi expat !

There's nothing wrong with your idea of using the catalog ore some other TapeManagementSystems.

But as a Systemprogrammer, i had been in some situations, where the using of a RDJCFB-call had been a suitable and neat solution for a problem. Also in former times, this was a standard practice for creating
legalized documents for the exchange of tapes beetween banks in europe.

But i agree with you, you have to be shure of what your'e doing.

Have a nice easter-weekend & regards,
UmeySan

expat · Posted: Wed Apr 04, 2007 2:33 pm

UmeySan · Posted: Wed Apr 04, 2007 3:17 pm

Yes Sir, expat !

From today 15hundred zulu time till 12/04/07 08hundred.
And in fact of information, the wether will become fine.
So i hope most of the girls would only be lightly dressed !!!

Prettige paasdagen & regards,
UmeySan (Frankfurt am Main / Germany)

mainframe_96 · New User Joined: 18 Dec 2006 Posts: 13 Location: usa

Hope this helps