Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...


Describe the DD statement, its meaning, syntax and keywords?

Answers were Sorted based on User's Feedback



Describe the DD statement, its meaning, syntax and keywords?..

Answer / sunitha

Ans: The DD statement links the external dataset to the
ddname coded within the executing program. It links the
files within the program code to the filenames known to the
MVS Operating system. The syntax is:
//DDANAME DD DSN=NAME,
// DISP=(NEW,CATLG,DELETE),
// DCB=(DSORG=PS,RECFM=FB,LRECL=80,BLKSIZE=800),
// SPACE=(CYL,(20,5),RLSE),
// UNIT=SYSDA

DSN- Name of the dataset- separated by periods, each name 1
to 8 characters, total 44 chars including periods.
DISP- It specifies the disposition of the dataset.
DISP=(status,normal-disposition,abnormal-disposition)
Status – The statuses NEW,MOD,OLD,SHR are the status of the
dataset at the beginning of the step.
NEW is given to create a new dataset. It is the default if
anything is not coded.
OLD designates an existing dataset with exclusive control.
SHR designates an existing dataset without exclusive
control.
MOD is used to extend the dataset if it exists or to create
a new one if it does not exist.
Normal-disposition- It directs the system on the
disposition of the data set (pass, keep, catlg, uncatlg,
delete) when the step ends normally.
Abnormal-disposition- It directs the system on the
disposition of the data set (keep, catlg, uncatlg, delete)
when the step ends abnormally.
DCB- Physical characteristics of a Data Set are described
by DCB Parameters. These parameters must be coded for newly
created data set as well as for existing Datasets.
• LRECL=n (VALUE IN BYTES)
• RECFM=(F/FB/V/VB/U)
• BLKSIZE= multiple of LRECL
• DSORG=(PS/PO/DA)
PO: specifies a partitioned Organization, DA: specifies a
direct organization.
SPACE=(space units,
(primary,secondary,dir),RLSE,CONTIG,MXIG,ROUND)
space unit - TRK(tracks)/CYL(cylinders)/BLOCKSIZE in bytes.
In our above example it allocates 20 cycles primary and if
required allocates 5 secondary cycles.
RLSE- Request to release the space that is primarily
allocated if unused.
CONTIG- Request for contiguous space.
MXIG- Request for large area of contiguous space.
ROUND- Request for entire cylinder for storage of dataset.
UNIT parameter indicates the information about input or
output device that will be used
by the dataset. It specifies a group name, device type, or
device number that identifies the
device where the file resides. The Format of the UNIT
parameter is UNIT= groupname/
device-type/device number.
VOL parameter is primarily used for tapes. A volume is the
portion of the storage device served by one read/write
mechanism. To request specific volumes, we code
VOL=SER=volume for one volume or VOL=SER=(volume, volume…)
for multiple volumes. Volume serial numbers are one to six
characters.
SYSOUT parameter is used to route the output to a device.
// DDNAME DD SYSOUT=CLASS

Is This Answer Correct ?    6 Yes 1 No

Describe the DD statement, its meaning, syntax and keywords?..

Answer / guest

The DD statement links the external dataset name (DSN) to
the DDNAME coded within the executing program. It links the
file names within the program code to the file names know to
the MVS operating system. The syntax is // ddname DD
DSN=dataset name. Other keywords after DSN are DISP, DCB,
SPACE, etc.

Is This Answer Correct ?    3 Yes 0 No

Post New Answer

More JCL Interview Questions

How do you send the output of a COBOL program to a member of a PDS?

7 Answers  


We have an output dataset in job with disp parameter as SHR. Can we write data in that file dataset?

2 Answers   CTS, IBM,


which utility is used to update pds?

1 Answers   IBM,


can we maintain 2 generations with different Lengths in Same GDG ?

3 Answers   RBS,


What is Backward Referencing ?

3 Answers   HSBC,


what is a steplib

4 Answers   CGI,


How to concatenate different LRECL of files?

2 Answers   IBM,


Explain the purpose of the dd keylen parameter?

0 Answers  


What do you feel makes a good program?

1 Answers  


How can we increment subscript and index?

1 Answers   CTS, IBM,


using cursor how can you fetch more than one record into a variable

3 Answers   Syntel,


I have a dataset with record length 40 in production, due to some requirements it was changed to 80. Then how can we know the jobs which are effected by this change and how can we resolve it.

3 Answers   iGate,


Categories