UDF 2.00 - OSTA - Optical Storage Technology Association

• The host shall perform read/modify/write to enable the apparent writing of single 2K
sectors.
• The packet length shall be set when the disc is formatted. The packet length shall be
32 sectors (64 KB).
• The host shall maintain a list of defects on the disc using a Non-Allocatable Space List
(see 3.3.7.1.2).
• Sparing shall be managed by the host via the sparable partition and a sparing table.
• Discs shall be formatted prior to use.
6.10.2.2 Formatting
Formatting shall consist of writing a lead-in, user data area, and lead-out. These areas
may be written in any order. This physical format may be followed by a verification pass.
Defects found during the verification pass shall be enumerated in the Non-Allocatable
Space list (see 3.3.7.1.2). Finally, file system root structures shall be recorded. These
mandatory file system and root structures include the Volume Recognition Sequence,
Anchor Volume Descriptor Pointers, a Volume Descriptor Sequence, a File Set
Descriptor and a Root Directory.
The Anchor Volume Descriptor Pointers shall be recorded at sectors 256 and N - 256,
where N is the Physical Address of the last addressable sector.
Allocation for sparing shall occur during the format process. The sparing allocation may
be zero in length.
The free space descriptors shall be recorded and shall reflect space allocated to defective
areas and sector sparing areas.
The format may include all available space on the medium. However, if requested by the
user, a subset may be formatted to save formatting time. That smaller format may be later
“grown” to the full available space.
UDF 2.00 April 3, 1998
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