Function librocksdb_sys::rocksdb_key_may_exist

pub unsafe extern "C" fn rocksdb_key_may_exist(
    db: *mut rocksdb_t, 
    options: *const rocksdb_readoptions_t, 
    key: *const c_char, 
    key_len: usize, 
    value: *mut *mut c_char, 
    val_len: *mut usize, 
    timestamp: *const c_char, 
    timestamp_len: usize, 
    value_found: *mut c_uchar
) -> c_uchar