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3.3.3.5 byte Extended Attributes
Section 3.2.1 describes how the value for this field is set. For file systems using a
VAT, the function of the LVHD UniqueID field in the LVID is taken over by the
VAT File Entry UniqueID field, see 3.2.1.1.
NOTE: For UDF 2.00 and higher, the Unique ID value used in the UDF Unique
ID Mapping Data is taken from the File Identifier Descriptor rather than from the
File Entry.
3.3.3.5 byte ExtendedAttributes[]
Certain extended attributes should be recorded in this field of the FileEntry for
performance reasons. Other extended attributes should be recorded in an ICB
pointed to by the field ExtendedAttributeICB. In the section on Extended
Attributes it will be specified which extended attributes should be recorded in this
field.
3.3.4 Extended Attributes
In order to handle some of the longer Extended Attributes (EAs) that may vary in
length, the following rules apply to the EA space.
1. All EAs with an attribute length greater than or equal to a logical block shall
be block aligned by starting and ending on a logical block boundary. The one
and only exception to this rule is the start of the first ECMA 167 EA.
2. Smaller EAs shall be constrained to an attribute length that is a multiple of 4
bytes.
3. Each Extended Attributes Space shall appear as a single contiguous logical
space constructed as follows:
ECMA 167 EAs
Non block aligned Implementation Use EAs
Block aligned Implementation Use EAs
Application Use EAs
NOTE: There may exist 2 Extended Attributes Spaces per file, one embeded in
the File Entry or Extended File Entry and the other as a separate space referenced
by the Extended Attribute ICB address in the File Entry or Extended File Entry.
Each Extended Attributes Space, if present, must have its own Extended Attribute
Header Descriptor (see the next section).
UDF 2.01
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