Key Definition Area

All unused or reserved areas must be initialized to binary zeros.

Offset	Type	Description of the Field
0	pic xx comp-x	Component count. For ordinary keys, the component count is 1. For split keys, the component count is the number of components making up the split key.
2	pic xx comp-x	Offset to first component definition area for this key. This offset is relative to the start of the global information area, starting at 0.
4	pic x comp-x	Key flags: Bit 7 - Reserved Bit 6 - Duplicates allowed Bit 5 - Reserved Bit 4 - Set to indicate that this is the prime key. If this is not set for any key, the File Handler assumes that the first key is the prime key. Bit 3 - Reserved Bit 2 - Reserved Bit 1 - Sparse key. See offset 6. Bit 0 - Reserved
5	pic x comp-x	Compression flags: Bits 7 - 4 Reserved Bit 3 - Compression of trailing nulls Bit 2 - Compression of trailing spaces Bit 1 - Compression of leading characters Bit 0 - Compression of duplicates
6	pic x comp-x	Sparse character. If bit 1 of the key flags (offset 4) is set, the key is suppressed if it is entirely made up of this character.
7	pic x(9) comp-x	Reserved