Function nvme_read_key 

pub unsafe extern "C" fn nvme_read_key(
    keyring_id: c_long,
    key_id: c_long,
    len: *mut c_int,
) -> *mut c_uchar

nvme_read_key() - Read key raw data @keyring_id: Id of the keyring holding %key_id @key_id: Key id @len: Length of the returned data

Links the keyring specified by @keyring_id into the session keyring and reads the payload of the key specified by @key_id. @len holds the size of the returned buffer. If @keyring is 0 the default keyring ‘.nvme’ is used.

Return: Pointer to the payload on success, or NULL with errno set otherwise.