SECTION G.6
1079
Up dating Example
with identifiers
8 0
and
9 0
have been deleted, as can be seen from the fact that
their entries in the cross-reference section end with the keyword
f
.
Example G.9
7 0 obj
[ 10 0 R
11 0 R
]
endobj
xref
0 1
0000000008
7 3
0000001978
0000000009
0000000000
65535 f
00000 n
00001 f
00001 f
trailer
<< /Size 12
/Root 1 0 R
/Prev 1855
>>
startxref
2027
%%EOF
The cross-reference section added at this stage contains four entries, representing
object number 0, the
Annots
array, and the two deleted text annotations.
•
The cross-reference entry for object number 0 is updated because it is the head
of the linked list of free entries and must now point to the entry for the newly
freed object number 8. The entry for object number 8 points to the entry for
object number 9 (the next free entry), while the entry for object number 9 is the
last free entry in the cross-reference table, indicated by the fact that it points
back to object number 0.
•
The entries for the two deleted text annotations are marked as free and as
having generation numbers of 1, which are used for any objects that reuse these
cross-reference entries. Keep in mind that, although the two objects have been
deleted, they are still present in the file. It is the cross-reference table that
records the fact that they have been deleted.