Read bytes from a constant database
#include <cdb.h>
#include <uint32.h>
int cdb_read(struct cdb *c,char *buf,unsigned long int len,uint32 position);
cdb_read reads len bytes starting at position from c to buf. You can use cdb_datapos or cdb_keypos to get position and cdb_datalen and cdb_keylen to get len.
buf needs to point to a memory region large enough to hold len bytes.
cdb_read returns 0 if everything went well, or -1 on error (setting errno appropriately.