Object oriented style:
class XMLWriter {Procedural style:
bool xmlwriter_start_dtd ( resource xmlwriter, string qualifiedName [, string publicId [, string systemId]] )Starts a DTD.
xmlwriter
Only for procedural calls. The XMLWriter resource that is being modified. This resource comes from a call to xmlwriter_open_uri() or xmlwriter_open_memory().
qualifiedName
The qualified name of the document type to create.
publicId
The external subset public identifier.
systemId
The external subset system identifier.