The structure of UDDF is made human readable and understandable. Nevertheless, processing of an UDDF file will normally be done via an XML parser (which is used by the application software to read the UDDF file). For this the UDDF structure is given in a document type definition (DTD).
The authors recommend to use validating XML parsers, which not only checks the syntactical correctness of the UDDF file, but also the logical structure. It is strongly recommended to check syntactic and logical correctness directly after generating (!!!) the UDDF file, to ensure that the UDDF file can unobjectionably be processed by other software.
UDDF XML XSD-Schema by Daniel Mohni (daniel at mohni dot net)
UDDF XML Schema by Boris Boesler (borisboesler at users dot sourceforge dot net)