UDF 2.00 - OSTA - Optical Storage Technology Association

2.3.8 Space Bitmap Descriptor
struct SpaceBitmap { /* ECMA 167 4/14.11 */
struct Tag DescriptorTag;
Uint32 NumberOfBits;
Uint32 NumberOfBytes;
byte
Bitmap[];
}
2.3.8.1 struct Tag DescriptorTag
The calculation and maintenance of the DescriptorCRC field of the Descriptor Tag
for the SpaceBitmap descriptor is optional. If the CRC is not maintained then both
the DescriptorCRC and DescriptorCRCLength fields shall be ZERO.
2.3.9 Partition Integrity Entry
struct PartitionIntegrityEntry { /* ECMA 167 4/14.13 */
struct tag DescriptorTag;
struct icbtag ICBTag;
struct timestamp RecordingTime;
Uint8
IntegrityType;
byte
Reserved[175];
struct EntityID ImplementationIdentifier;
byte
ImplementationUse[256];
}
With the functionality of the Logical Volume Integrity Descriptor this descriptor is
not needed, therefore this descriptor shall not be recorded.
2.3.10 Allocation Descriptors
When constructing the data area of a file an implementation has several types of allocation
descriptors from which to choose. The following guidelines shall be followed in choosing
the proper allocation descriptor to be used:
Short Allocation Descriptor - For a Logical Volume that resides on a single
Volume with no intent to expand the Logical Volume beyond the single volume
Short Allocation Descriptors should be used. For example a Logical Volume
created for a stand alone drive.
NOTE: Refer to section 2.2.2.2 on the MaximumInterchangeLevel.
Long Allocation Descriptor - For a Logical Volume that resides on a single
Logical Volume with intent to later expand the Logical Volume beyond the single
volume, or a Logical Volume that resides on multiple Volumes Long Allocation
Descriptors should be used. For example a Logical Volume created for a jukebox.
UDF 2.00 April 3, 1998
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