-<!ELEMENT OpenGLAPI (category+)>
+<!ELEMENT OpenGLAPI (category?, xi:include?, OpenGLAPI?)+>
<!ELEMENT category (type*, enum*, function*)*>
<!ELEMENT type EMPTY>
<!ELEMENT enum (size*)>
<!ELEMENT return EMPTY>
<!ELEMENT glx EMPTY>
+<!ELEMENT xi:include (xi:fallback)?>
+<!ATTLIST xi:include
+ xmlns:xi CDATA #FIXED "http://www.w3.org/2001/XInclude"
+ href CDATA #REQUIRED
+ parse (xml|text) "xml"
+ encoding CDATA #IMPLIED>
+<!ELEMENT xi:fallback ANY>
+<!ATTLIST xi:fallback
+ xmlns:xi CDATA #FIXED "http://www.w3.org/2001/XInclude">
+
+
<!ATTLIST category name NMTOKEN #REQUIRED
- number NMTOKEN #IMPLIED>
+ number NMTOKEN #IMPLIED
+ window_system NMTOKEN #IMPLIED>
<!ATTLIST type name NMTOKEN #REQUIRED
size NMTOKEN #REQUIRED
+ float (true | false) "false"
+ unsigned (true | false) "false"
glx_name NMTOKEN #IMPLIED>
<!ATTLIST enum name NMTOKEN #REQUIRED
count CDATA #IMPLIED