Multiple instances and DMX (Network Artnet Sender / Receiver)

[circuitb]

Hi,

just found this strange behaviour in a multi vvvv instances scenario:
something like you can only have DMX nodes in one instance!

open 1st vvvv instance
put a DMX (Network Artnet Sender or Receiver)
open 2nd vvvv instance (/allowmultiple)
try to add another DMX (Network Artnet Sender or Receiver)
nothing happen in the patch window!
but tty report

00:07:41 * : [MainLoop.TMMainLoop.DoTimer: error occured in Graph.TMBasicNode.PrepareGraphCB](MainLoop.TMMainLoop.DoTimer: error occured in Graph.TMBasicNode.PrepareGraphCB): Could not bind socket. Address and port are already in use.
00:07:41 - : To help us track this error down, enable the ExceptionDialog via the menu or starting vvvv with /showexceptions.

[bjoern]

Well this isn’t really a bug. Artnet is sent via UDP on port 6454 iirc. When this protocol/port is in use by an app e.g. vvvv instance A, it can no longer be used by another one (vvvv instance B) .

@wikipedia

Only one process may bind to a specific IP address and port combination using the same transport protocol. Common application failures, sometimes called port conflicts, occur when multiple programs attempt to bind to the same port numbers on the same IP address using the same protocol.

If you need to send artnet from different instances just send the values to one instance (via shared memory for example) and forward it from there.

[circuitb]

thanks for the explanation bjoern!

[sebl]

you can set the artnet-port for each instance with a commandline parameter