* malformed.
   */
  @Throws(IOException::class)
  fun checkLowercase(name: ByteString): ByteString {
    for (i in 0 until name.size) {
      if (name[i] in 'A'.code.toByte()..'Z'.code.toByte()) {
        throw IOException("PROTOCOL_ERROR response malformed: mixed case name: ${name.utf8()}")
      }
    }
    return name
  }