Data set header section

Offsets		Name	Length	Format	Description
0	0	S42DSNXT	4	binary	Offset to the next data set header section (0 if the last data set).
4	4	S42DSN	44	EBCDIC	Data set name.
48	30	S42DSTYP	1	binary	Data set type. Value Meaning 0 Other 1 Physical sequential 2 PDS 3 PDSE 4 Direct access 5 ISAM 6 EXCP 7 Extended physical sequential data set 10 HFS 16 KSDS data component 17 KSDS index component 18 Variable RRDS data component 19 Variable RRDS index component 20 Fixed length RRDS 21 Linear data set 22 ESDS
49	31	S42DSCOD S42FIRST *	1	binary	Entry descriptor flag Bit Meaning 1... .... First data set entry since Open. .xxx xxxx Reserved.
50	32	S42DSFL1 S42DSGSR S42DSLSR S42DSRLS S42DSNSR S42DSEXC S42DSFXD S42DSPL S42DSEF S42DSEFC	1	binary	Data set descriptor flags Bit Meaning 11xx xxxx VSAM buffer flags 11.. .... GSR 10.. .... LSR 01.. .... RLS 00.. .... NSR ..x. .... Reserved ....1 .... Open for EXCP processing ..... 1... Non-VSAM fixed length records ..... .1.. Program library ..... ..1. Extended format ..... ...1 Compressed format
51	33	*	1	EBCDIC	Reserved.
52	34	S42DSIOO	4	binary	Offset to data set I/O statistics section.
56	38	S42DSAMO	4	binary	Offset to access method statistics section.
60	3C	S42DSVOL	6	EBCDIC	Volume serial number.
66	42	S42DSDEV	2	binary	Device number.
68	44	S42DSSC	8	EBCDIC	Storage class name.
76	4C	S42DSBSZ	4	binary	Block size. For concatenated data sets, this data is taken from the first data set.
80	50	S42DSTRP	2	binary	Number of stripes
82	52	*	6	EBCDIC	Reserved.