XML Companion, The, Third Edition

External entity declarations

A base definition has no effect on external entity references that use a relative reference. This is due to the fact that these declarations occur outside of the root element, so are not in the scope of that element (or of any other element).

In the following example, the DTD file 'coll.dtd' will not be sought in the 'Orwell' directory, and neither will the document '1984.xml':

                      <!-- NOT AFFECTED -->
<!DOCTYPE collection SYSTEM "coll.dtd"
[ ...
  ...                <!-- NOT AFFECTED -->
  <!ENTITY book1984 SYSTEM "1984.xml">
  ...
]>
<collection xml:base="file:///d:/colls/Orwell/">
  ...
  &book1984;
  ...
</collection>