An Introduction to the Search/Retrieve URL Service (SRU)
SRW and SRU are "brother and sister" standardised Web Service-based protocols for accomplishing the task of querying Internet-accessible databases and returning search results. If index providers were to expose their services via SRW and/or SRU, then the content of the 'hidden Web' would become more accessible and there would be less of a need to constantly re-invent the interfaces to these indexes.
The author would like to thank the people on the ZNG mailing list for their assistance. They were in- valuable during the learning process. Special thanks goes to Ralph Levan of OCLC who helped clarify the meaning and purpose of XML packing.
The home page for SRW/U is http://www.loc.gov/z3950/agency/zing/srw/.
CQL is fully described at http://www.loc.gov/z3950/agency/zing/cql/.
The home page of MARC::Record is http://marc.sourceforge.net/.
Xsltproc is an application written against two C libraries called libxml and libxslt described at ht-
Swish-e is an indexer/search engine application with a C as well as a Perl interface. See: ht- tp://swish-e.org/.
The canonical URL of OCKHAM is http://ockham.org/.