public static PooledBuffer HeaderAsBinary(HTTP2FrameHeaderAndPayload header) { // https://httpwg.org/specs/rfc7540.html#FrameHeader var buffer = BufferPool.Get(9, true); BufferHelper.SetUInt24(buffer, 0, header.PayloadLength); buffer[3] = (byte)header.Type; buffer[4] = header.Flags; BufferHelper.SetUInt31(buffer, 5, header.StreamId); return(new PooledBuffer { Data = buffer, Length = 9 }); }