WNSEARCH(3) WordNet™ Library Functions WNSEARCH(3)NAME
findtheinfo, findtheinfo_ds, is_defined, in_wn, index_lookup,
parse_index, getindex, read_synset, parse_synset, free_syns,
free_synset, free_index, traceptrs_ds, do_trace - functions for search‐
ing the WordNet database
SYNOPSIS
#include "wn.h"
char *findtheinfo(char *searchstr, int pos, int ptr_type, int
sense_num);
SynsetPtr findtheinfo_ds(char *searchstr, int pos, int ptr_type, int
sense_num );
unsigned int is_defined(char *searchstr, int pos);
unsigned int in_wn(char *searchstr, int pos);
IndexPtr index_lookup(char *searchstr, int pos);
IndexPtr parse_index(long offset, int dabase, char *line);
IndexPtr getindex(char *searchstr, int pos);
SynsetPtr read_synset(int pos, long synset_offset, char *searchstr);
SynsetPtr parse_synset(FILE *fp, int pos, char *searchstr);
void free_syns(SynsetPtr synptr);
void free_synset(SynsetPtr synptr);
void free_index(IndexPtr idx);
SynsetPtr traceptrs_ds(SynsetPtr synptr, int ptr_type, int pos, int
depth);
char *do_trace(SynsetPtr synptr, int ptr_type, int pos, int depth);
DESCRIPTION
These functions are used for searching the WordNet database. They gen‐
erally fall into several categories: functions for reading and parsing
index file entries; functions for reading and parsing synsets in data
files; functions for tracing pointers and hierarchies; functions for
freeing space occupied by data structures allocated with malloc(3).
In the following function descriptions, pos is one of the following:
1 NOUN
2 VERB
3 ADJECTIVE
4 ADVERB
findtheinfo() is the primary search algorithm for use with database
interface applications. Search results are automatically formatted,
and a pointer to the text buffer is returned. All searches listed in
WNHOME/include/wn.h can be done by findtheinfo(). findtheinfo_ds() can
be used to perform most of the searches, with results returned in a
linked list data structure. This is for use with applications that
need to analyze the search results rather than just display them.
Both functions are passed the same arguments: searchstr is the word or
collocation to search for; pos indicates the syntactic category to
search in; ptr_type is one of the valid search types for searchstr in
pos. (Available searches can be obtained by calling is_defined()
described below.) sense_num should be ALLSENSES if the search is to be
done on all senses of searchstr in pos, or a positive integer indicat‐
ing which sense to search.
findtheinfo_ds() returns a linked list data structures representing
synsets. Senses are linked through the nextss field of a Synset data
structure. For each sense, synsets that match the search specified
with ptr_type are linked through the ptrlist field. See Synset Naviga‐
tion , below, for detailed information on the linked lists returned.
is_defined() sets a bit for each search type that is valid for search‐
str in pos, and returns the resulting unsigned integer. Each bit num‐
ber corresponds to a pointer type constant defined in
WNHOME/include/wn.h. For example, if bit 2 is set, the HYPERPTR search
is valid for searchstr. There are 29 possible searches.
in_wn() is used to find the syntactic categories in the WordNet data‐
base that contain one or more senses of searchstr. If pos is ALL_POS,
all syntactic categories are checked. Otherwise, only the part of
speech passed is checked. An unsigned integer is returned with a bit
set corresponding to each syntactic category containing searchstr. The
bit number matches the number for the part of speech. 0 is returned if
searchstr is not present in pos.
index_lookup() finds searchstr in the index file for pos and returns a
pointer to the parsed entry in an Index data structure. searchstr must
exactly match the form of the word (lower case only, hyphens and under‐
scores in the same places) in the index file. NULL is returned if a
match is not found.
parse_index() parses an entry from an index file and returns a pointer
to the parsed entry in an Index data structure. Passed the byte offset
and syntactic category, it reads the index entry at the desired loca‐
tion in the corresponding file. If passed line, line contains an index
file entry and the database index file is not consulted. However, off‐
set and dbase should still be passed so the information can be stored
in the Index structure.
getindex() is a "smart" search for searchstr in the index file corre‐
sponding to pos. It applies to searchstr an algorithm that replaces
underscores with hyphens, hyphens with underscores, removes hyphens and
underscores, and removes periods in an attempt to find a form of the
string that is an exact match for an entry in the index file corre‐
sponding to pos. index_lookup() is called on each transformed string
until a match is found or all the different strings have been tried.
It returns a pointer to the parsed Index data structure for searchstr,
or NULL if a match is not found.
read_synset() is used to read a synset from a byte offset in a data
file. It performs an fseek(3) to synset_offset in the data file corre‐
sponding to pos, and calls parse_synset() to read and parse the synset.
A pointer to the Synset data structure containing the parsed synset is
returned.
parse_synset() reads the synset at the current offset in the file indi‐
cated by fp. pos is the syntactic category, and searchstr, if not
NULL, indicates the word in the synset that the caller is interested
in. An attempt is made to match searchstr to one of the words in the
synset. If an exact match is found, the whichword field in the Synset
structure is set to that word's number in the synset (beginning to
count from 1).
free_syns() is used to free a linked list of Synset structures allo‐
cated by findtheinfo_ds(). synptr is a pointer to the list to free.
free_synset() frees the Synset structure pointed to by synptr.
free_index() frees the Index structure pointed to by idx.
traceptrs_ds() is a recursive search algorithm that traces pointers
matching ptr_type starting with the synset pointed to by synptr. Set‐
ting depth to 1 when traceptrs_ds() is called indicates a recursive
search; 0 indicates a non-recursive call. synptr points to the data
structure representing the synset to search for a pointer of type
ptr_type. When a pointer type match is found, the synset pointed to is
read is linked onto the nextss chain. Levels of the tree generated by
a recursive search are linked via the ptrlist field structure until
NULL is found, indicating the top (or bottom) of the tree. This func‐
tion is usually called from findtheinfo_ds() for each sense of the
word. See Synset Navigation , below, for detailed information on the
linked lists returned.
do_trace() performs the search indicated by ptr_type on synset synptr
in syntactic category pos. depth is defined as above. do_trace()
returns the search results formatted in a text buffer.
Synset Navigation
Since the Synset structure is used to represent the synsets for both
word senses and pointers, the ptrlist and nextss fields have different
meanings depending on whether the structure is a word sense or pointer.
This can make navigation through the lists returned by findtheinfo_ds()
confusing.
Navigation through the returned list involves the following:
Following the nextss chain from the synset returned moves through the
various senses of searchstr. NULL indicates that end of the chain of
senses.
Following the ptrlist chain from a Synset structure representing a
sense traces the hierarchy of the search results for that sense. Sub‐
sequent links in the ptrlist chain indicate the next level (up or down,
depending on the search) in the hierarchy. NULL indicates the end of
the chain of search result synsets.
If a synset pointed to by ptrlist has a value in the nextss field, it
represents another pointer of the same type at that level in the hier‐
archy. For example, some noun synsets have two hypernyms. Following
this nextss pointer, and then the ptrlist chain from the Synset struc‐
ture pointed to, traces another, parallel, hierarchy, until the end is
indicated by NULL on that ptrlist chain. So, a synset representing a
pointer (versus a sense of searchstr) having a non-NULL value in nextss
has another chain of search results linked through the ptrlist chain of
the synset pointed to by nextss.
If searchstr contains more than one base form in WordNet (as in the
noun axes, which has base forms axe and axis), synsets representing the
search results for each base form are linked through the nextform
pointer of the Synset structure.
WordNet Searches
There is no extensive description of what each search type is or the
results returned. Using the WordNet interface, examining the source
code, and reading wndb(5) are the best ways to see what types of
searches are available and the data returned for each.
Listed below are the valid searches that can be passed as ptr_type to
findtheinfo(). Passing a negative value (when applicable) causes a
recursive, hierarchical search by setting depth to 1 when traceptrs()
is called.
┌─────────────────┬───────┬─────────┬────────────────────────────────────────────┐
│ptr_type │ Value │ Pointer │ Search │
│ │ │ Symbol │ │
├─────────────────┼───────┼─────────┼────────────────────────────────────────────┤
│ANTPTR │ 1 │ ! │ Antonyms │
│HYPERPTR │ 2 │ @ │ Hypernyms │
│HYPOPTR │ 3 │ ∼ │ Hyponyms │
│ENTAILPTR │ 4 │ * │ Entailment │
│SIMPTR │ 5 │ & │ Similar │
│ISMEMBERPTR │ 6 │ #m │ Member meronym │
│ISSTUFFPTR │ 7 │ #s │ Substance meronym │
│ISPARTPTR │ 8 │ #p │ Part meronym │
│HASMEMBERPTR │ 9 │ %m │ Member holonym │
│HASSTUFFPTR │ 10 │ %s │ Substance holonym │
│HASPARTPTR │ 11 │ %p │ Part holonym │
│MERONYM │ 12 │ % │ All meronyms │
│HOLONYM │ 13 │ # │ All holonyms │
│CAUSETO │ 14 │ > │ Cause │
│PPLPTR │ 15 │ < │ Participle of verb │
│SEEALSOPTR │ 16 │ ^ │ Also see │
│PERTPTR │ 17 │ \ │ Pertains to noun or derived from adjective │
│ATTRIBUTE │ 18 │ \= │ Attribute │
│VERBGROUP │ 19 │ $ │ Verb group │
│DERIVATION │ 20 │ + │ Derivationally related form │
│CLASSIFICATION │ 21 │ ; │ Domain of synset │
│CLASS │ 22 │ - │ Member of this domain │
│SYNS │ 23 │ n/a │ Find synonyms │
│FREQ │ 24 │ n/a │ Polysemy │
│FRAMES │ 25 │ n/a │ Verb example sentences and generic frames │
│COORDS │ 26 │ n/a │ Noun coordinates │
│RELATIVES │ 27 │ n/a │ Group related senses │
│HMERONYM │ 28 │ n/a │ Hierarchical meronym search │
│HHOLONYM │ 29 │ n/a │ Hierarchical holonym search │
│WNGREP │ 30 │ n/a │ Find keywords by substring │
│OVERVIEW │ 31 │ n/a │ Show all synsets for word │
│CLASSIF_CATEGORY │ 32 │ ;c │ Show domain topic │
│CLASSIF_USAGE │ 33 │ ;u │ Show domain usage │
│CLASSIF_REGIONAL │ 34 │ ;r │ Show domain region │
│CLASS_CATEGORY │ 35 │ -c │ Show domain terms for topic │
│CLASS_USAGE │ 36 │ -u │ Show domain terms for usage │
│CLASS_REGIONAL │ 37 │ -r │ Show domain terms for region │
│INSTANCE │ 38 │ @i │ Instance of │
│INSTANCES │ 39 │ ∼i │ Show instances │
└─────────────────┴───────┴─────────┴────────────────────────────────────────────┘
findtheinfo_ds() cannot perform the following searches:
SEEALSOPTR
PERTPTR
VERBGROUP
FREQ
FRAMES
RELATIVES
WNGREP
OVERVIEW
NOTES
Applications that use WordNet and/or the morphological functions must
call wninit() at the start of the program. See wnutil(3) for more
information.
In all function calls, searchstr may be either a word or a collocation
formed by joining individual words with underscore characters (_).
The SearchResults structure defines fields in the wnresults global
variable that are set by the various search functions. This is a way
to get additional information, such as the number of senses the word
has, from the search functions. The searchds field is set by findthe‐
info_ds().
The pos passed to traceptrs_ds() is not used.
SEE ALSOwn(1), wnb(1), wnintro(3), binsrch(3), malloc(3), morph(3), wnutil(3),
wnintro(5).
WARNINGSparse_synset() must find an exact match between the searchstr passed
and a word in the synset to set whichword. No attempt is made to
translate hyphens and underscores, as is done in getindex().
The WordNet database and exception list files must be opened with
wninit prior to using any of the searching functions.
A large search may cause findtheinfo() to run out of buffer space. The
maximum buffer size is determined by computer platform. If the buffer
size is exceeded the following message is printed in the output buffer:
"Search too large. Narrow search and try again...".
Passing an invalid pos will probably result in a core dump.
WordNet 3.0 Dec 2006 WNSEARCH(3)
