NAME¶
cdb_find - look up a key in a constant database
SYNTAX¶
#include <cdb.h>
#include <uint32.h>
int cdb_find(struct cdb *
c,char *
key,unsigned long int
keylen);
int cdb_datalen(struct cdb *
c);
int cdb_datapos(struct cdb *
c);
int cdb_findnext(struct cdb *
c,char *
key,unsigned long int
keylen);
DESCRIPTION¶
cdb_find looks for
key. If cdb_find returns 0, the database does
not contain that key; stop. If cdb_find returns -1, there was a read error;
abort.
cdb_datalen returns the length of the data associated with the
key. Use it to allocate a pointer
p with enough space to hold
the data.
cdb_datapos returns the position of the data inside the file. Use it as
argument to cdb_read to retrieve the data.
There may be several records under a single key. You can use
cdb_findnext
to find the next record under this key.
EXAMPLE¶
static struct c;
if (cdb_find(&c,key,strlen(key)>0) {
char *buf=alloca(cdb_datalen(&c));
cdb_read(&c,buf,cdb_datalen(&c),cdb_datapos(&c));
write(1,buf,cdb_datalen(&c));
}
SEE ALSO¶
cdb_read(3),
cdb_init(3),
cdb_free(3),
cdbmake(1)
