c# - How can I handle when a UdpClient is listening on an address which is no longer available? -


i'm using udpclient, bound provided end point, listen incoming packets. code follows:

        ...          string myipaddress = "192.168.1.100";         int myport = 50000;          ipendpoint selfendpoint = new ipendpoint(ipaddress.parse(myipaddress), myport);         ipendpoint anysourceendpoint = new ipendpoint(ipaddress.any, 0);          udpclient receivingclient = new udpclient();         receivingclient.client.bind(selfendpoint); // can throw.          receivingclient.receive(ref anysourceendpoint);         ...

if interface ip address '192.168.1.100' not exist, throws socketexception` (as expected). in case such interface exists, udpclient binds , waits incoming packet. problem follows.

how can detect case blocking on receive , interface's address no longer available?

for example, application running , waiting incoming packets. user disables network interface on system. application still assumes can receive packets, though cannot.

the closes i've come setting receivetimeout on client , re-creating/binding udpclient when timeout occurs; i'm hoping alternative or other suggestions.

udp stateless. rule of thumb is: cannot rely on anything. not on sending, not on receiving, not on getting errors when goes wrong.

udp sits quietly , waits next packet. binding endpoint, merely tell discard not sent explicitly endpoint. if user disables network card, still waits packets sent bound endpoint, though became impossible packets arrive. , activate card again, , sends endpoint, udp client receive it, if nothing happened.

long story short: udpclient not choice of software find out if network card disabled. have find out other way , disable udpclient manually, if want handle case. instance, initialize tcp on other port. in fact produce error if disable network card.


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