Control Field Values for Fixed-Length Relative-Record Data Sets

In a fixed-length RRDS, the possible hexadecimal values in the control field of an RDF are:

X'04': The RDF at X'04' gives the length of an empty slot.
X'00': The RDF at X'00' gives the length of a slot that contains a record.

Every control interval in a fixed-length RRDS contains the same number of slots and the same number of RDFs; one for each slot. The first slot is described by the rightmost RDF. The second slot is described by the next RDF to the left, and so on.