<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE SystemDefinition [
 <!ELEMENT SystemDefinition (systemModel)>
 <!ATTLIST SystemDefinition
  name CDATA #REQUIRED
  schema CDATA #REQUIRED>
 <!ELEMENT systemModel (layer+)>
 <!ELEMENT layer (block*|collection*)*>
 <!ATTLIST layer
  name CDATA #REQUIRED
  long-name CDATA #IMPLIED
  levels NMTOKENS #IMPLIED
  span CDATA #IMPLIED>
 <!ELEMENT block (subblock*|collection*)*>
 <!ATTLIST block
  levels NMTOKENS #IMPLIED
  span CDATA #IMPLIED
  level NMTOKEN #IMPLIED
  name CDATA #REQUIRED
  long-name CDATA #IMPLIED>
 <!ELEMENT subblock (collection)*>
 <!ATTLIST subblock
  name CDATA #REQUIRED
  long-name CDATA #IMPLIED>
 <!ELEMENT collection (component)*>
 <!ATTLIST collection
  name CDATA #REQUIRED
  long-name CDATA #IMPLIED
  level NMTOKEN #IMPLIED>
 <!ELEMENT component (unit)*>
 <!ATTLIST component
  name CDATA #REQUIRED
  long-name CDATA #IMPLIED
  deprecated CDATA #IMPLIED
  introduced CDATA #IMPLIED
  contract CDATA #IMPLIED
  plugin (Y|N) 'N'
  filter CDATA #IMPLIED
  class NMTOKENS #IMPLIED
  supports CDATA #IMPLIED
  purpose (optional|mandatory|development) 'optional'>
 <!ELEMENT unit EMPTY>
 <!ATTLIST unit
  mrp CDATA #IMPLIED
  filter CDATA #IMPLIED
  bldFile CDATA #IMPLIED
  root CDATA #IMPLIED
  version NMTOKEN #IMPLIED
  prebuilt NMTOKEN #IMPLIED
  late (Y|N) #IMPLIED
  priority CDATA #IMPLIED>
]>
<SystemDefinition schema="2.0.1" name="Symbian^4">
 <systemModel>
  <layer name="app" long-name="Applications" levels="services apps">
   <block name="printing" level="services" long-name="Printing"/>
  </layer>
 </systemModel>
</SystemDefinition>