Function encode_poll_reply 

pub fn encode_poll_reply(
    out: &mut [u8],
    callsign: &Callsign,
    reflector_callsign: &Callsign,
) -> Result<usize, EncodeError>

Encode a 17-byte poll (keepalive) reply.

Identical to encode_poll_request — the server side of the poll is byte-for-byte symmetric in this codec (matching xlxd’s 17-byte keepalive shape).

Errors

Returns EncodeError::BufferTooSmall if out.len() < 17.