DSM/Tape Catalog Operator Interface (MEDIACOM) Manual

Tape Label Formats
DSM/Tape Catalog Operator Interface (MEDIACOM) Manual—429828-010
A-5
IBM-MVS Beginning-of-File-Section Labels
Table A-6. IBM-MVS HDR2 Label
Character
Position Field Name
Length
in Bytes Content
1 to 3 Label Identifier 3 HDR
4 Label Number 1 2
5 Record Format 1 F (fixed length)
U (undefined length)
6 to 10 Block Length 5 Number of bytes per block
11 to 15 Record Length 5 Number of bytes per record
16 Tape Density
(5180 Tape Drive only)
1 Value
0 (full function mode)
Space (not a 5180 device)
17 Data Set Position 1 0 (no tape switch has occurred)
1 (a tape switch previously occurred)
18 to 34 Job/Job Step Identification 17 Spaces
35 to 36 Tape Recording Technique 2 Spaces
37 Control Character 1 Space
38 Reserved for Future
Standardization
1Space
39 Block Attribute 1 B (records are blocked)
Space (records are not blocked)
40 to 42 Reserved for Future
Standardization
8Spaces
43 to 46 Serial Number (5180 Tape
Drive only)
4 NNNN (unit's serial number in
hexadecimal)
Spaces (not a 5180 device)
47 Device Address (5180 Tape
Drive only)
1 0 (5180 device)
Space (not a 5180 device)
48 Checkpoint Data Set
Identifier
1Space
49 to 80 Reserved for Future
Standardization
32 Spaces