Data set control information—DFHDCT TYPE=SDSCI

This macro defines the data control block (DCB) for an extrapartition transient data destination.

You must also code a DFHDCT TYPE=EXTRA macro, to define the destination.

Extrapartition data sets can be blocked or unblocked, of fixed or variable length.

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>>-DFHDCT--TYPE=SDSCI--,DSCNAME=name--+-----------------+------->
                                      '-,BLKSIZE=length-'   

>--+---------------------+--+----------------------+------------>
   |          .-1------. |  |           .-IGNORE-. |   
   '-,BUFNO=--+--------+-'  '-,ERROPT=--+--------+-'   
              '-number-'                '-SKIP---'     

>--+------------------------+--+-----------------+-------------->
   '-,RECFORM=--+-FIXUNB--+-'  '-,RECSIZE=length-'   
                +-FIXUNBA-+                          
                +-FIXUNBM-+                          
                +-FIXBLK--+                          
                +-FIXBLKA-+                          
                +-FIXBLKM-+                          
                +-VARBLK--+                          
                +-VARBLKA-+                          
                +-VARBLKM-+                          
                +-VARUNB--+                          
                +-VARUNBA-+                          
                '-VARUNBM-'                          

>--+----------------------+--+-----------------------+---------><
   '-,REWIND=--+-LEAVE--+-'  |            .-INPUT--. |   
               '-REREAD-'    '-,TYPEFLE=--+--------+-'   
                                          +-OUTPUT-+     
                                          '-RDBACK-'     

TYPE=SDSCI
Indicates that this DCT entry contains data set control information.
BLKSIZE=length
Code this with the length of the block, in bytes.

For V format data sets, each block consists of a block descriptor word followed by one or more logical records. The value coded for BLKSIZE must include 4 bytes for the block descriptor word, and also make allowance for the largest possible logical record (which itself includes 4 bytes of record descriptor word).

If the data set already exists, BLKSIZE can be omitted. However, if BLKSIZE is coded for an input data set it should match the data set BLKSIZE.

BUFNO={1∨number}
Code this with the number of buffers to be provided. Any number up to 255 may be coded.
DSCNAME=name
Code this with the 1-to 8-character data set control name. This name must be the same as that coded in the DSCNAME operand of any associated DFHDCT TYPE=EXTRA macro.

The name used for DSCNAME must be used as the ddname on the DD statement, and is also used as the name for the DCB that is created.

The name must not start with the letters “DFH”, which are reserved for use by CICS®, unless it is describing one of the standard destinations. Use of the prefix “DFH” may cause assembly errors and future compatibility problems, because the DSCNAME parameter becomes an externally-specified name.

ERROPT={IGNORE∨SKIP}
Code this with the error option to be performed if an I/O error occurs.
IGNORE
The block that caused the error is accepted.
SKIP
The block that caused the error is skipped.
RECFORM={FIXUNB∨FIXUNBA∨FIXUNBM∨FIXBLK∨FIXBLKA∨ FIXBLKM∨VARBLK∨VARBLKA∨VARBLKM∨VARUNB∨VARUNBA∨ VARUNBM}
Code this with the record format of the data set.
FIXUNB
Fixed unblocked records
FIXBLK
Fixed blocked records
VARBLK
Variable blocked records
VARUNB
Variable unblocked records
FIXUNBA,FIXBLKA,VARBLKA,VARUNBA
Fixed unblocked, fixed blocked, variable blocked, or variable unblocked records respectively, together with ASA control characters
FIXUNBM,FIXBLKM,VARBLKM,VARUNBM
Fixed unblocked, fixed blocked, variable blocked, or variable unblocked records respectively, together with machine control characters.
RECSIZE=length
Code this with the length of the record, in bytes.

For V format data sets, each logical record consists of a record descriptor word followed by a data record. The value coded for RECSIZE must include 4 bytes for the record descriptor word (or LLBB), and also make allowance for the largest possible data record.

RECSIZE=length need be coded only for RECFM=FIXBLK.

REWIND={LEAVE∨REREAD}
Code this with the disposition of a tape data set.
LEAVE
The current tape is positioned to the logical end of the data set.
REREAD
The current tape is positioned to reprocess the data set.
TYPEFLE={INPUT∨OUTPUT∨RDBACK}
Code this with the type of data set.
INPUT
An input data set
OUTPUT
An output data set
RDBACK
An input data set that is to be read backward.
Note: This is appropriate only when the data set has been defined on magnetic tape.

An extrapartition SDSCI can be either input or output, but not both.

For more information on the above operands, see MVS/ESA Data Administration: Macro Instruction Reference.