__bt_open
DB *__bt_open(const char *, int, mode_t, const BTREEINFO *, int);
return (__bt_open(fname, flags & USE_OPEN_FLAGS,
dbp = __bt_open(openinfo->bfname,
dbp = __bt_open(NULL, O_RDWR, S_IRUSR | S_IWUSR, NULL, dflags);