mode (get | set) "set">
<!ATTLIST param name NMTOKEN #REQUIRED
type CDATA #REQUIRED
+ client_only (true | false) "false"
count NMTOKEN #IMPLIED
counter (true | false) "false"
count_scale NMTOKEN "1"
param:
name - name of the parameter
type - fully qualified type (e.g., with "const", etc.)
+ client_only - boolean flag set on parameters which are interpreted only
+ by the client and are not present in the protocol encoding (e.g.,
+ the stride parameters to Map1f, etc.)
count - for counted arrays (e.g., the 'lists' parameter to glCallLists),
the parameter or literal that represents the count. For functions
like glVertex3fv it will be a litteral, for others it will be one of