xtra UPnP
-- v0.2 (c) 2019 Valentin Schmidt

*UPnP_addPort integer port, integer protocol, string description, *ip
*UPnP_removePort integer port, integer protocol
*UPnP_listPorts


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UPnP_addPort (integer port, integer protocol, string description, * string ip) -> bool success
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Tries to add a new port-forwarding rule to the router settings.

Parameter 'protocol': 0 for UDP, 1 for TCP

If parameter 'ip' is omitted, the current PC's local LAN IP is used.

Returns TRUE if new port-forwarding was successfully added, otherwise FALSE.


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UPnP_removePort (integer port, integer protocol) -> bool success
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Tries to remove an existing port-forwarding rule from the router settings.

Parameter 'protocol': 0 for UDP, 1 for TCP

Returns TRUE if port-forwarding was successfully removed, otherwise FALSE.


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UPnP_listPorts () -> list portForwardings
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Returns all existing UPnP-based port-forwarding rules in the current router settings.

Each item in the returned list is a lingo list of this form:
[string ip, string description, string protocol ("UDP" or "TCP"), integer internalPort, integer externalPort]

If the router doesn't support UPnP, an empty list is returned.