The meaning of the first three optional parameters is exactly the same as in the Allow command.
When processing a document with the URL
matching pattern, indexer
(similar to CheckMP3) downloads only
a little part of the document and tries to find
MP3 tags.
On success, indexer parses MP3 tags. In case when no MP3 tags are found,
indexer does NOT download the rest of the document
and word information about this document is not put into the database.
Indexing MP3 files is explained in details in the Section called Creating an MP3 search engine in Chapter 6.