Initialize IODF

This utility function initializes a defined VSAM DIV file into an IODF. Each IODF contains as first record a header record, called the IHR (IODF Header Record). This record contains, among other information, the size of the IODF, an optional description of up to 128 characters, as well as an option whether activity logging is enabled or disabled. HCD rejects any data set that does not contain such a header record.

The VSAM DIV file must be preallocated using DD name HCDIODFT. You can add an optional IODF description using DD name HCDCNTL.

This function is invoked by passing the following parameter string.

|--INITIODF--SIZE=nnnn--+------------------+--+--------+--------|
                        |          .-YES-. |  '-,FORCE-'
                        '-,ACTLOG=-+-NO--+-'
 

SIZE=nnnn

nnnn specifies the size of the IODF in 4K blocks. This value must not be greater than the number of records specified with the IDCAMS Define Cluster control statement. If SIZE=0 is specified, the number of allocated records of the VSAM data set is used. If an existing IODF is re-initialized, the specified size value must not be smaller than the number of allocated IODF blocks.

ACTLOG=(YES | NO)

specifies enabling of activity logging. If omitted, the default is YES.

FORCE

indicates that reinitialization of an existing IODF is allowed.

Batch invocation

A data set must be allocated to the following DD names when invoking the batch utility.

The following example shows the IDCAMS control statements necessary to define a VSAM DIV file.

DEFINE CLUSTER (NAME (SYS1.IODF01.CLUSTER) -
       LINEAR -
       RECORDS (1024) -
       VOLUMES (DATA02) -
       ) -
       DATA (NAME (SYS1.IODF01))

For an example see the batch job on page ***.