title: Append byte to a byte buffer in golang
body: <p>I have a message byte Buffer and I would like to append a byte at the end of the Buffer</p>
  
  <p>I tried to append like this:</p>
  
  <pre><code>append(message.Buf, 0xff)
  first argument to append must be slice; have *bytes.Buffer
  
  append(0xff,message.Buf)
  first argument to append must be slice; have untyped number
  </code></pre>
  
  <p>How can I make the 0xff as a slice to append? </p>