
Introduction Specifying the DD Statement
6-2 User Reference
Specifying the DD Statement
Introduction
All DD statements follow the same format. The identifying characters are '* //', which must be
specified in columns 1-4. These are followed immediately by the DD name.
* //
ddname
DD
parameter-expressions
ddname performs the same function as the DTF name (filename). It specifies the
program's logical name for the dataset. It must begin in column 5.
If you use a DD statement for a DTF that your program defines as a unit record DTF (DTFCD
or DTFPR), ddname is the SYS number that is specified in that DTF. A unit record DTF is
generated for COBOL programs when the SELECT statement contains an assignment name
that specifies the class UR.
Do not use ddname in continuation statements or in the second and following statements of a
concatenation.
Some DTF names are invalid for DD statements. Some have special meanings. See 6-5 in
this manual for more information.
DD specifies the DD operation. Place at least one blank immediately before and after it. Do
not repeat the DD operation in continuation statements.
You can specify many MVS-compatible parameters to define your datasets. The parameters
that follow the DD operation specify the type of processing to be done for the dataset. Some
parameters are different for:
•
Tape and disk datasets (including GDIUR datasets)
• Standard system datasets
•
SYSIPT data
• Dummy datasets
Not all MVS DD parameters are supported by the BIM-EPIC DD facility. BIM-EPIC ignores
unsupported and unrecognized parameters and subparameters. Supported parameters are
discussed in the following sections.
DD Statement
Identifier (* //)
Format
DD Name
DD (operation)
Additional
Parameters
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