pub unsafe extern "C" fn rocksdb_delete_range_cf(
    db: *mut rocksdb_t,
    options: *const rocksdb_writeoptions_t,
    column_family: *mut rocksdb_column_family_handle_t,
    start_key: *const c_char,
    start_key_len: usize,
    end_key: *const c_char,
    end_key_len: usize,
    errptr: *mut *mut c_char
)