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CDBR(3)                    Library Functions Manual                    CDBR(3)

     cdbr, cdbr_open, cdbr_open_mem, cdbr_entries, cdbr_get, cdbr_find,
     cdbr_close - constant database access methods

     #include <cdbr.h>

     struct cdbr *
     cdbr_open(const char *path, int flags);

     struct cdbr *
     cdbr_open_mem(void *base, size_t size, int flags,
         void (*unmap)(void *, void *, size_t), void *cookie);

     cdbr_entries(struct cdbr *cdbr);

     cdbr_get(struct cdbr *cdbr, uint32_t index, const void **data,
         size_t *datalen);

     cdbr_find(struct cdbr *cdbr, const void *key, size_t keylen,
         const void **data, size_t *datalen);

     cdbr_close(struct cdbr *cdbr);

     The cdbr library provides a space efficient (key,value) database based on
     perfect hashing.

     A cdb database is opened for reading by calling cdbr_open().  The only
     supported value for flags is CDBR_DEFAULT.  The function returns a handle
     to pass to the other functions.  The database is closed by invoking
     cdbr_close().  All resources associated with the handle are freed and the
     memory returned by cdbr_get() and cdbr_find() is invalidated.
     cdbr_open_mem() works like cdbr_open(), but takes a memory reference to
     the content of the database file.  If unmap is not NULL, it is called by
     cdbr_close() with cookie, base and size as arguments.  It is not called
     by cdbr_open_mem() on error.

     The number of records in the database can be obtained by calling
     cdbr_entries().  Records can be obtained by record number using
     cdbr_get() or by key using cdbr_find().  Both functions return 0 on
     success and update data and datalen accordingly.  The location *data
     remains valid until cdbr_close() is called.  It is the responsibility of
     the caller of cdbr_find() to ensure that the key matches the returned
     data.  The function returns the only possible match, but the database
     doesn't store the keys to minimize overhead.

     nbperf(1), cdbw(3), db(3), cdb(5)

     Support for the cdb format first appeared in NetBSD 6.0.

     The cdbr and cdbw functions have been written by Joerg Sonnenberger

NetBSD 10.99                   December 1, 2018                   NetBSD 10.99