- library
- semweb
- rdf_db.pl -- Core RDF database
 - rdf_cache.pl -- Cache RDF triples
 - rdfs.pl -- RDFS handling
 - rdf_persistency.pl -- RDF persistency plugin
 - rdf_litindex.pl -- Search literals
 - rdf_ntriples.pl -- Process files in the RDF N-Triples format
 - rdf11.pl -- RDF 1.1 API
 - sparql_client.pl -- SPARQL client library
 - turtle.pl -- Turtle: Terse RDF Triple Language
 - rdf_turtle_write.pl -- Turtle - Terse RDF Triple Language writer
 - rdf_http_plugin.pl -- RDF HTTP Plugin
 - rdf_library.pl -- RDF Library Manager
 - rdf_sandbox.pl -- Declare RDF API sandbox-safe
 - rdf_zlib_plugin.pl -- RDF compressed-data plugin
 
 
 - semweb
 
- rdf_db:rdf_open_hook(+Scheme, +URL, +HaveModified, -Stream, -Cleanup, -Modified, -Format, +Options) is semidet[multifile, library(semweb/rdf_http_plugin)]
 - Load hook implementation for HTTP(S) URLs.
- Arguments:
 - 
HaveModified - is bound to a timestamp (number) if we already have a copy and that copy was modified at HaveModified. Modified - is bound to unknown,not_modifiedor a timestamp.