redland(3)


NAME

   redland - Resource Description Framework (RDF) Library

VERSION

   1.0.16

SYNOPSIS

    #include <redland.h>

DESCRIPTION

   redland is a library providing support for the Resource Description
   Framework (RDF) written in ANSI C with APIs in several other languages.

   This manual page lists most of the redland public API functions but
   does not claim to be a complete summary of the entire API.  For the
   complete API with full details of the function interface, see the HTML
   API documentation either on the Redland web site at
   <http://librdf.org/> or with the software release in the docs/api
   directory.

FUNCTIONS

   The functions defined by redland are all defined with the "librdf_"
   prefix

   class world
   librdf_world* librdf_new_world(void)
   void librdf_free_world(librdf_world* world)
   void librdf_world_open(librdf_world* world)
   void librdf_world_set_error(librdf_world* world, void* user_data, void
   (*error_fn)(void* user_data, const char* msg, ...))
   void librdf_world_set_warning(librdf_world* world, void* user_data,
   void (*warning_fn)(void* user_data, const char* msg, ...))
   void librdf_world_set_digest(librdf_world*, const char* name)
   void librdf_world_set_uris_hash(librdf_world* world, librdf_hash*
   uris_hash)
   const char* librdf_world_get_feature(librdf_world* world, librdf_uri*
   feature)
   int librdf_world_set_feature(librdf_world* world, librdf_uri* feature,
   const char* value)

   class iterator
   librdf_iterator* librdf_new_iterator(librdf_world* world, void*
   context, int (*is_end)(void*), void* (*get_next)(void*), void
   (*finished)(void*))
   void librdf_free_iterator(librdf_iterator*)
   int librdf_iterator_end(librdf_iterator* iterator)
   int librdf_iterator_finished(librdf_iterator* iterator)
   int librdf_iterator_next(librdf_iterator* iterator)
   void* librdf_iterator_get_object(librdf_iterator* iterator)
   void* librdf_iterator_get_context(librdf_iterator* iterator)
   void* librdf_iterator_get_key(librdf_iterator* iterator)
   void* librdf_iterator_get_value(librdf_iterator* iterator)
   int librdf_iterator_add_map(librdf_iterator* iterator, void*
   (*fn)(void* context, void* item), void* context)
   void* librdf_iterator_map_remove_duplicate_nodes(void* item, void*
   user_data)

   class digest
   void librdf_digest_register_factory(librdf_world* world, const char*
   name, void (*factory) (librdf_digest_factory*))
   librdf_digest_factory* librdf_get_digest_factory(librdf_world* world,
   const char* name)
   librdf_digest* librdf_new_digest(librdf_world* world, char* name)
   librdf_digest* librdf_new_digest_from_factory(librdf_world* world,
   librdf_digest_factory* factory)
   void librdf_free_digest(librdf_digest* digest)
   void librdf_digest_init(librdf_digest* digest)
   void librdf_digest_update(librdf_digest* digest, unsigned char* buf,
   size_t length)
   void librdf_digest_final(librdf_digest* digest)
   void* librdf_digest_get_digest(librdf_digest* digest)
   char* librdf_digest_to_string(librdf_digest* digest)
   void librdf_digest_print(librdf_digest* digest, FILE* fh)

   class uri
   librdf_uri* librdf_new_uri(librdf_world* world, const unsigned char *
   string)
   librdf_uri* librdf_new_uri_from_uri(librdf_uri* uri)
   librdf_uri* librdf_new_uri_from_uri_local_name(librdf_uri* uri, const
   unsigned char* local_name)
   void librdf_free_uri(librdf_uri* uri)
   unsigned char* librdf_uri_as_string(librdf_uri* uri)
   unsigned char* librdf_uri_as_counted_string(librdf_uri* uri, size_t*
   len_p)
   librdf_digest* librdf_uri_get_digest(librdf_uri* uri)
   void librdf_uri_print>(librdf_uri* uri, FILE* fh)
   unsigned char* librdf_uri_to_string(librdf_uri* uri)
   unsigned char* librdf_uri_to_counted_string(librdf_uri* uri, size_t*
   len_p)
   int librdf_uri_equals(librdf_uri* first_uri, librdf_uri* second_uri)
   int librdf_uri_is_file_uri(librdf_uri* uri)
   const char* librdf_uri_to_filename(librdf_uri* uri)
   librdf_uri* librdf_new_uri_normalised_to_base(const unsigned char*
   uri_string, librdf_uri* source_uri, librdf_uri* base_uri)
   librdf_uri* librdf_new_uri_relative_to_base(librdf_uri* base_uri, const
   unsigned char* uri_string)
   librdf_uri* librdf_new_uri_from_filename(librdf_world* world, const
   char* filename)

   class node
   librdf_node* librdf_new_node(librdf_world* world)
   librdf_node* librdf_new_node_from_uri_string(librdf_world* world, const
   char* string)
   librdf_node* librdf_new_node_from_uri(librdf_world* world, librdf_uri*
   uri)
   librdf_node* librdf_new_node_from_uri_local_name(librdf_world* world,
   librdf_uri* uri, const char* local_name)
   librdf_node* librdf_new_node_from_normalised_uri_string(librdf_world*
   world, const char* uri_string, librdf_uri* source_uri, librdf_uri*
   base_uri)
   librdf_node* librdf_new_node_from_literal(librdf_world* world, const
   char* string, const char* xml_language, int xml_space, int is_wf_xml)
   librdf_node* librdf_new_node_from_typed_literal(librdf_world* world,
   const unsigned char* string, const char* xml_language, librdf_uri*
   datatype_uri)
   librdf_node* librdf_new_node_from_blank_identifier(librdf_world* world,
   const unsigned char* identifier)
   librdf_node* librdf_new_node_from_node(librdf_node* node)
   void librdf_node_init(librdf_world* world, librdf_node* node)
   void librdf_free_node(librdf_node* r)
   librdf_uri* librdf_node_get_uri(librdf_node* node)
   librdf_node_type librdf_node_get_type(librdf_node* node)
   unsigned char* librdf_node_get_literal_value(librdf_node* node)
   unsigned char*
   librdf_node_get_literal_value_as_counted_string(librdf_node* node,
   size_t* len_p)
   char* librdf_node_get_literal_value_as_latin1(librdf_node* node)
   char* librdf_node_get_literal_value_language(librdf_node* node)
   int librdf_node_get_literal_value_is_wf_xml(librdf_node* node)
   librdf_uri* librdf_node_get_literal_value_datatype_uri(librdf_node*
   node)
   int librdf_node_get_li_ordinal(librdf_node* node)
   unsigned char* librdf_node_get_blank_identifier(librdf_node* node)
   int librdf_node_is_resource(librdf_node* node)
   int librdf_node_is_literal(librdf_node* node)
   int librdf_node_is_blank(librdf_node* node)
   librdf_digest* librdf_node_get_digest(librdf_node* node)
   size_t librdf_node_encode(librdf_node* node, unsigned char* buffer,
   size_t length)
   size_t librdf_node_decode(librdf_node* node, unsigned char* buffer,
   size_t length)
   unsigned char* librdf_node_to_string(librdf_node* node)
   unsigned char* librdf_node_to_counted_string(librdf_node* node, size_t*
   len_p)
   void librdf_node_print(librdf_node* node, FILE* fh)
   int librdf_node_equals(librdf_node* first_node, librdf_node*
   second_node)

   class concepts
   The library provides macros for all of the RDF and RDFS concepts -
   nodes and URIs.  For example, "LIBRDF_MS_Alt" for the librdf_node for
   the rdf:Alt concept and "LIBRDF_MS_Alt_URI" for the librdf_uri for the
   URI reference of rdf:Alt.

   "LIBRDF_URI_RDF_MS" and "LIBRDF_URI_RDF_SCHEMA" provide the librdf_uri
   objects for the RDF and RDFS namespace URIs.  They must be copied using
   librdf_new_uri_from_uri to be shared correctly.

   void librdf_get_concept_by_name(librdf_world* world, int is_ms, const
   char* name, librdf_uri **uri_p, librdf_node **node_p)

   class statement
   librdf_statement* librdf_new_statement(librdf_world* world)
   librdf_statement* librdf_new_statement_from_statement(librdf_statement*
   statement)
   librdf_statement* librdf_new_statement_from_nodes(librdf_world* world,
   librdf_node* subject, librdf_node* predicate, librdf_node* object)
   void librdf_statement_init(librdf_world* world, librdf_statement*
   statement)
   void librdf_statement_clear(librdf_statement* statement)
   void librdf_free_statement(librdf_statement* statement)
   librdf_node* librdf_statement_get_subject(librdf_statement* statement)
   void librdf_statement_set_subject(librdf_statement* statement,
   librdf_node* subject)
   librdf_node* librdf_statement_get_predicate(librdf_statement*
   statement)
   void librdf_statement_set_predicate(librdf_statement* statement,
   librdf_node* predicate)
   librdf_node* librdf_statement_get_object(librdf_statement* statement)
   void librdf_statement_set_object(librdf_statement* statement,
   librdf_node* object)
   int librdf_statement_is_complete(librdf_statement* statement)
   char* librdf_statement_to_string(librdf_statement* statement)
   void librdf_statement_print(librdf_statement* statement, FILE* fh)
   int librdf_statement_equals(librdf_statement* statement1,
   librdf_statement* statement2)
   int librdf_statement_match(librdf_statement* statement,
   librdf_statement* partial_statement)
   size_t librdf_statement_encode(librdf_statement* statement, unsigned
   char* buffer, size_t length)
   size_t librdf_statement_encode_parts(librdf_statement* statement,
   unsigned char* buffer, size_t length, librdf_statement_part fields)
   size_t librdf_statement_decode(librdf_statement* statement, unsigned
   char* buffer, size_t length)
   size_t librdf_statement_decode_parts(librdf_statement* statement,
   librdf_node** context_node, unsigned char* buffer, size_t length)

   class model
   librdf_model* librdf_new_model(librdf_world* world, librdf_storage*
   storage, char* options_string)
   librdf_model* librdf_new_model_with_options(librdf_world* world,
   librdf_storage* storage, librdf_hash* options)
   librdf_model* librdf_new_model_from_model(librdf_model* model)
   void librdf_free_model(librdf_model* model)
   int librdf_model_size(librdf_model* model)
   int librdf_model_add(librdf_model* model, librdf_node* subject,
   librdf_node* predicate, librdf_node* object)
   int librdf_model_add_string_literal_statement(librdf_model* model,
   librdf_node* subject, librdf_node* predicate, char* string, char*
   xml_language, int xml_space, int is_wf_xml)
   int librdf_model_add_typed_literal_statement(librdf_model* model,
   librdf_node* subject, librdf_node* predicate, const unsigned char*
   string, char* xml_language, librdf_uri* datatype_uri)
   int librdf_model_add_statement(librdf_model* model, librdf_statement*
   statement)
   int librdf_model_add_statements(librdf_model* model, librdf_stream*
   statement_stream)
   int librdf_model_remove_statement(librdf_model* model,
   librdf_statement* statement)
   int librdf_model_contains_statement(librdf_model* model,
   librdf_statement* statement)
   int librdf_model_has_arc_in(librdf_model* model, librdf_node* node,
   librdf_node* property)
   int librdf_model_has_arc_out(librdf_model* model, librdf_node* node,
   librdf_node* property)
   librdf_stream* librdf_model_as_stream(librdf_model* model)
   librdf_stream* librdf_model_find_statements(librdf_model* model,
   librdf_statement* statement)
   librdf_stream* librdf_model_find_statements_in_context(librdf_model*
   model, librdf_statement* statement, librdf_node* context_node)
   librdf_stream* librdf_model_find_statements_with_options(librdf_model*
   model, librdf_statement* statement, librdf_node* context_node,
   librdf_hash* options)
   librdf_iterator* librdf_model_get_contexts(librdf_model* model)
   librdf_iterator* librdf_model_get_sources(librdf_model* model,
   librdf_node* arc, librdf_node* target)
   librdf_iterator* librdf_model_get_arcs(librdf_model* model,
   librdf_node* source, librdf_node* target)
   librdf_iterator* librdf_model_get_targets(librdf_model* model,
   librdf_node* source, librdf_node* arc)
   librdf_node* librdf_model_get_source(librdf_model* model, librdf_node*
   arc, librdf_node* target)
   librdf_node* librdf_model_get_arc(librdf_model* model, librdf_node*
   source, librdf_node* target)
   librdf_node* librdf_model_get_target(librdf_model* model, librdf_node*
   source, librdf_node* arc)
   librdf_iterator* librdf_model_get_arcs_in(librdf_model* model,
   librdf_node* node)
   librdf_iterator* librdf_model_get_arcs_out(librdf_model* model,
   librdf_node* node)
   int librdf_model_add_submodel(librdf_model* model, librdf_model*
   sub_model)
   int librdf_model_remove_submodel(librdf_model* model, librdf_model*
   sub_model)
   void librdf_model_print(librdf_model* model, FILE* fh)
   int librdf_model_context_add_statement(librdf_model* model,
   librdf_node* context, librdf_statement* statement)
   int librdf_model_context_add_statements(librdf_model* model,
   librdf_node* context, librdf_stream* stream)
   int librdf_model_context_remove_statement(librdf_model* model,
   librdf_node* context, librdf_statement* statement)
   int librdf_model_context_remove_statements(librdf_model* model,
   librdf_node* context)
   librdf_stream* librdf_model_context_as_stream(librdf_model* model,
   librdf_node* context)
   librdf_stream* librdf_model_query(librdf_model* model, librdf_query*
   query)
   librdf_stream* librdf_model_query_string(librdf_model* model, const
   char* name, librdf_uri* uri, const unsigned char* query_string)
   void librdf_model_sync(librdf_model* model)
   librdf_storage* librdf_model_get_storage(librdf_model* model)
   librdf_node* librdf_model_get_feature(librdf_model* model, librdf_uri*
   feature) =item int librdf_model_set_feature(librdf_model* model,
   librdf_uri* feature, librdf_node* value)

   class storage
   void librdf_storage_register_factory(const char* name, void (*factory)
   (librdf_storage_factory*))
   librdf_storage* librdf_new_storage(librdf_world* world, char*
   storage_name, char* name, char* options_string)
   librdf_storage* librdf_new_storage_with_options(librdf_world* world,
   char* storage_name, char* name, librdf_hash* options)
   librdf_storage* librdf_new_storage_from_storage(librdf_storage*
   old_storage)
   librdf_storage* librdf_new_storage_from_factory(librdf_world* world,
   librdf_storage_factory* factory, char* name, librdf_hash* options)
   void librdf_free_storage(librdf_storage* storage)
   int librdf_storage_open(librdf_storage* storage, librdf_model* model)
   int librdf_storage_close(librdf_storage* storage)
   int librdf_storage_get(librdf_storage* storage, void* key, size_t
   key_len, void **value, size_t* value_len, unsigned int flags)
   int librdf_storage_size(librdf_storage* storage)
   int librdf_storage_add_statement(librdf_storage* storage,
   librdf_statement* statement)
   int librdf_storage_add_statements(librdf_storage* storage,
   librdf_stream* statement_stream)
   int librdf_storage_remove_statement(librdf_storage* storage,
   librdf_statement* statement)
   int librdf_storage_contains_statement(librdf_storage* storage,
   librdf_statement* statement)
   librdf_stream* librdf_storage_serialise(librdf_storage* storage)
   librdf_stream* librdf_storage_find_statements(librdf_storage* storage,
   librdf_statement* statement)
   librdf_iterator* librdf_storage_get_sources(librdf_storage* storage,
   librdf_node* arc, librdf_node* target)
   librdf_iterator* librdf_storage_get_arcs(librdf_storage* storage,
   librdf_node* source, librdf_node* target)
   librdf_iterator* librdf_storage_get_targets(librdf_storage* storage,
   librdf_node* source, librdf_node* arc)
   librdf_iterator* librdf_storage_get_arcs_in(librdf_storage* storage,
   librdf_node* node)
   librdf_iterator* librdf_storage_get_arcs_out(librdf_storage* storage,
   librdf_node* node)
   int librdf_storage_has_arc_in(librdf_storage* storage, librdf_node*
   node, librdf_node* property)
   int librdf_storage_has_arc_out(librdf_storage* storage, librdf_node*
   node, librdf_node* property)
   int librdf_storage_context_add_statement(librdf_storage* storage,
   librdf_node* context, librdf_statement* statement)
   int librdf_storage_context_add_statements(librdf_storage* storage,
   librdf_node* context, librdf_stream* stream)
   int librdf_storage_context_remove_statement(librdf_storage* storage,
   librdf_node* context, librdf_statement* statement)
   int librdf_storage_context_remove_statements(librdf_storage* storage,
   librdf_node* context)
   librdf_stream* librdf_storage_context_as_stream(librdf_storage*
   storage, librdf_node* context)
   int librdf_storage_supports_query(librdf_storage* storage,
   librdf_query* query)
   librdf_stream* librdf_storage_query(librdf_storage* storage,
   librdf_query* query)
   void librdf_storage_sync(librdf_storage* storage)

   class parser
   void librdf_parser_register_factory(librdf_world* world, const char*
   name, const char* mime_type, const char* uri_string, void (*factory)
   (librdf_parser_factory*))
   librdf_parser* librdf_new_parser(librdf_world* world, const char* name,
   const char* mime_type, librdf_uri* type_uri)
   librdf_parser* librdf_new_parser_from_factory(librdf_world* world,
   librdf_parser_factory* factory)
   void librdf_free_parser(librdf_parser* parser)
   librdf_stream* librdf_parser_parse_as_stream(librdf_parser* parser,
   librdf_uri* uri, librdf_uri* base_uri)
   int librdf_parser_parse_into_model(librdf_parser* parser, librdf_uri*
   uri, librdf_uri* base_uri, librdf_model* model)
   librdf_stream* librdf_parser_parse_string_as_stream(librdf_parser*
   parser, const unsigned char* string, librdf_uri* base_uri)
   int librdf_parser_parse_string_into_model(librdf_parser* parser, const
   unsigned char* string, librdf_uri* base_uri, librdf_model* model)
   void librdf_parser_set_error(librdf_parser* parser, void* user_data,
   void (*error_fn)(void* user_data, const char* msg, ...))
   void librdf_parser_set_warning(librdf_parser* parser, void* user_data,
   void (*warning_fn)(void* user_data, const char* msg, ...))
   librdf_node* librdf_parser_get_feature(librdf_parser* parser,
   librdf_uri* feature)
   int librdf_parser_set_feature(librdf_parser* parser, librdf_uri*
   feature, librdf_node* value)

   class serializer
   librdf_serializer* librdf_new_serializer(librdf_world* world, const
   char *name, const char *mime_type, librdf_uri *type_uri)
   librdf_serializer* librdf_new_serializer_from_factory(librdf_world*
   world, librdf_serializer_factory *factory)
   void librdf_free_serializer(librdf_serializer *serializer)
   int librdf_serializer_serialize_model(librdf_serializer* serializer,
   FILE* handle, librdf_uri* base_uri, librdf_model* model)
   int librdf_serializer_serialize_model_to_file(librdf_serializer*
   serializer, const char *name, librdf_uri* base_uri, librdf_model*
   model)
   void librdf_serializer_set_error(librdf_serializer* serializer, void
   *user_data, void (*error_fn)(void *user_data, const char *msg, ...))
   void librdf_serializer_set_warning(librdf_serializer* serializer, void
   *user_data, void (*warning_fn)(void *user_data, const char *msg, ...))
   librdf_node* librdf_serializer_get_feature(librdf_serializer*
   serializer, librdf_uri* feature)
   int librdf_serializer_set_feature(librdf_serializer* serializer,
   librdf_uri* feature, librdf_node* value)b
   int librdf_serializer_set_namespace(librdf_serializer* serializer,
   librdf_uri* uri, const char* prefix)

   class stream
   librdf_stream* librdf_new_stream(librdf_world* world, void* context,
   int (*end_of_stream)(void*), librdf_statement*
   (*next_statement)(void*), void (*finished)(void*))
   librdf_stream* librdf_new_stream_from_node_iterator(librdf_iterator*
   iterator, librdf_statement* statement, librdf_statement_part field)
   void librdf_free_stream(librdf_stream* stream)
   int librdf_stream_end(librdf_stream* stream)
   int librdf_stream_next(librdf_stream* stream)
   librdf_statement* librdf_stream_get_object(librdf_stream* stream)
   void* librdf_stream_get_context(librdf_stream* stream)
   void librdf_stream_set_map(librdf_stream* stream, librdf_statement*
   (*map)(void* context, librdf_statement* statement), void* map_context)
   void librdf_stream_print(librdf_stream* stream, FILE* fh)

EXAMPLES

     #include <redland.h>

     librdf_storage *storage;
     librdf_model* model;
     librdf_statement* statement;
     librdf_world* world

     world=librdf_new_world();

     librdf_world_open(world);

     storage=librdf_new_storage(world, "hashes", "test", "hash-type='bdb',dir='.'");
     model=librdf_new_model(world, storage, NULL);
     statement=librdf_new_statement_from_nodes(world, librdf_new_node_from_uri_string(world, "http://purl.org/net/dajobe/"), librdf_new_node_from_uri_string(world, "http://purl.org/dc/elements/1.1/creator"), librdf_new_node_from_literal(world, "Dave Beckett", NULL, 0));

     librdf_model_add_statement(model, statement);
     librdf_free_statement(statement);

     librdf_model_print(model, stdout);

     librdf_free_model(model);
     librdf_free_storage(storage);
     librdf_free_world(world);

SEE ALSO

   libraptor(3), libxml(4).

HISTORY

   The redland RDF library was created by Dave Beckett in June 2000.

AUTHOR

   Dave Beckett <http://purl.org/net/dajobe/>,





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Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.





Free Books


The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.


Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.





Education


Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.


Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.