In this example, a relative record cluster is defined.

//DEFCLU4  JOB   ...
//STEP1    EXEC  PGM=IDCAMS
//SYSPRINT DD    SYSOUT=A
//SYSIN    DD    *
     DEFINE CLUSTER -
           (NAME(EXAMPLE.RRDS1) -
           RECORDSIZE(100 100) -
           VOLUMES(VSER01) -
           TRACKS(10 5) -
           NUMBERED) -
         CATALOG(USERCAT)
/*

The DEFINE CLUSTER command builds a cluster entry and a data entry to define the relative record cluster EXAMPLE.RRDS1 in the user catalog. The DEFINE CLUSTER command allocates ten tracks for the cluster's use. The command's parameters are:

• NAME specifies that the cluster's name is EXAMPLE.RRDS1.
• RECORDSIZE specifies that the records are fixed-length, 100 byte records. Average and maximum record length must be equal for a fixed-length relative record data set, but not equal for a variable-length RRDS.
• VOLUMES specifies that the cluster is to reside on volume VSER01. This example assumes that the volume is already cataloged in the user catalog, USERCAT.
• TRACKS specifies that 10 tracks are allocated for the cluster. When the cluster is extended, it is to be extended in increments of 5 tracks.
• NUMBERED specifies that the cluster's data organization is to be relative record.
• CATALOG specifies the catalog name.