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Interfacing with UDP on localhost

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Interfacing with UDP on localhost

Postby mmyers7 » Thu Jul 04, 2019 2:30 pm

Hi All,

I'm working on a little project in which I am using the generic protocol to interface with and controlling FlightGear over UDP on the localhost network. Recently I have run into issues sending data from FlightGear. Listening with Wireshark and short python script I don't see an open connection like I used to.

A little more background, I am using the localhost IP for input and output with different port numbers for each. I vaguely remember reading on the Forum that you need different IP addresses and port numbers for each (not sure if that is true). I've tried several things with my XML file. I used to get an output with only one property in my XML, but no longer. The last thing I have tried is grabbing the exact XML from the Generic Protocol wiki page, but still no dice. Things starting going downhill when I was prototyping the input side. To rule that out I have removed all input capabilities.

Any thoughts on where I have gone wrong or things to try would be greatly appreciated.
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Re: Interfacing with UDP on localhost

Postby wkitty42 » Thu Jul 04, 2019 3:37 pm

AIUI you only need different port numbers for input and output but that depends on the application... you would use the same IP number or host name either way... that's all i can offer at the moment...
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Re: Interfacing with UDP on localhost

Postby SurferTim » Sun Jul 07, 2019 10:14 am

wkitty42 is correct. You can use the same IP but you must use separate ports. Bind won't let you use a port twice. I use this for testing all the time.
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