Examples of the DCB parameter

Example 1

//DD1   DD    DSNAME=ALP,DISP=(,KEEP),VOLUME=SER=44321,
//            UNIT=3400-6,DCB=(RECFM=FB,LRECL=240,BLKSIZE=960,
//            DEN=1,TRTCH=C)

DD statement DD1 defines a new data set named ALP. The DCB parameter contains the information necessary to complete the data control block.

Example 2

//DD1A  DD    DSNAME=EVER,DISP=(NEW,KEEP),UNIT=3380,
//            DCB=(RECFM=FB,LRECL=326,BLKSIZE=23472),
//            SPACE=(23472,(200,40))

DD statement DD1A defines a new data set named EVER on a 3380. The DCB parameter contains the information necessary to complete the data control block.

//DD1B  DD    DSNAME=EVER,DISP=(NEW,KEEP),UNIT=3380,
//            RECFM=FB,LRECL=326,
//            SPACE=(23472,(200,40))

DD statement DD1B is the same as the DD1A statement except that it shows the alternate syntax for the DCB keyword subparameters. Also, because BLKSIZE is omitted, the system will select an optimum block size for the data.

Example 3

//DD2   DD    DSNAME=BAL,DISP=OLD,DCB=(RECFM=F,LRECL=80,
//            BLKSIZE=80)
//DD3   DD    DSNAME=CNANN,DISP=(,CATLG,DELETE),UNIT=3400-6,
//            LABEL=(,NL),VOLUME=SER=663488,DCB=*.DD2

DD statement DD3 defines a new data set named CNANN and requests that the system copy the DCB subparameters from DD statement DD2, which is in the same job step.

Example 4

//DD4   DD    DSNAME=JST,DISP=(NEW,KEEP),UNIT=SYSDA,
//            SPACE=(CYL,(12,2)),DCB=(A.B.C,KEYLEN=8)

DD statement DD4 defines a new data set named JST and requests that the system copy the DCB information from the data set label of the cataloged data set named A.B.C. If the data set label contains a key length specification, it is overridden by the KEYLEN coded on this DD statement.

Example 5

//DD5   DD    DSNAME=SMAE,DISP=OLD,
//            DCB=(*.STEP1.PROCSTP5.DD8,BUFNO=5)

DD statement DD5 defines an existing, cataloged data set named SMAE and requests that the system copy DCB subparameters from DD statement DD8, which is contained in the procedure step named PROCSTP5. The cataloged procedure is called by EXEC statement STEP1. Any of the DCB subparameters coded on DD statement DD8 are ignored if they are specified in the program. If the DCB BUFNO subparameter is not specified in the program, five buffers are assigned.