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Re: Question on sending data over UDP endpoints
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Re: Question on sending data over UDP endpoints

At 0:00 +0400 1/7/04, Igor garnov wrote:
My Carbon CFM application uses Open Transport and works with endpoints in asynchronous mode, installing a notifier routine.

Is this running on traditional Mac OS, or Mac OS X? The OT implementations are quite different.

if I use "OTSndUData" to send some data to a foreign host, should I also install an OT timer that fires in, say, 5 seconds if no reply is given, or will my notifier routine be called with "T_UDERR" code to indicate that the foreign host is down / is not listening on the port specified? Will I actually receive an ICMP message, which will consequently trigger "T_UDERR" event?

You can't rely on getting the ICMP error packet. Many hosts will send you an ICMP error if the UDP packet wasn't delivered, but other hosts will ignore you. [Various sites on the Internet have taken to swallowing ICMP packets, which is dumb, but there you go.] If your machine does get the ICMP packet, OT will deliver it to you at a T_UDERR. It will also deliver it to any other endpoint that's listening for ICMP messages.

Should I call OTRcvUDErr before calling OTCloseProvider?

This should not be necessary.

After 5 seconds my timer fires and I call OTCloseProvider on the endpooint,
after which my application freezes.

Which sounds like a serious problem. This shouldn't happen. I'd offer you some debugging hints, but they vary depending on what OS you're running. If you can follow-up with some details, I can make further suggestions.

S+E
--
Quinn "The Eskimo!" <http://www.apple.com/developer/>
Apple Developer Technical Support * Networking, Communications, Hardware
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References: 
 >Question on sending data over UDP endpoints (From: Igor garnov <email@hidden>)



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