limit: Int,
    ): Int =
      try {
        // Canonicalize the port string to skip '\n' etc.
        val portString = input.canonicalize(pos = pos, limit = limit, encodeSet = "")
        val i = portString.toInt()
        if (i in 1..65535) i else -1
      } catch (_: NumberFormatException) {
        -1 // Invalid port.
      }
  }

  companion object {

// gay : Registry Services, LLC
// https://www.iana.org/domains/root/db/gay.html
gay

// gbiz : Charleston Road Registry Inc.
// https://www.iana.org/domains/root/db/gbiz.html
gbiz

// gdn : Joint Stock Company "Navigation-information systems"
// https://www.iana.org/domains/root/db/gdn.html
gdn

// gea : GEA Group Aktiengesellschaft
// https://www.iana.org/domains/root/db/gea.html
gea