Works with rosrun but not with roslaunch

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Hello,

I have a video data being streamed into a local host (to a socket). When I run my executable using rosrun it works well, but when I use roslaunch to run the same node, it says the resource is temporarily unavailable (error from the socket).

The error message I get is this:

process[cmvideo_node-1]: started with pid [9553]
VDS: unknown host: __name:=cmvideo_node
Can't initialise vds client (returns -2, Resource temporarily unavailable)
terminate called after throwing an instance of 'class_loader::LibraryUnloadException'
  what():  Attempt to unload library that class_loader is unaware of.
[cmvideo_node-1] process has died [pid 9553, exit code -6, cmd /home/providentia/Documents/bridge_demo/workspace/cm_sim/devel/lib/cmvideo/cmvideo_node __name:=cmvideo_node __log:=/home/providentia/.ros/log/395ae26a-80d3-11e7-abe7-f48e38a43ac3/cmvideo_node-1.log].
log file: /home/providentia/.ros/log/395ae26a-80d3-11e7-abe7-f48e38a43ac3/cmvideo_node-1*.log
all processes on machine have died, roslaunch will exit
shutting down processing monitor...
... shutting down processing monitor complete
done

I use the following for rosrun: rosrun cmvideo cmvideo_node

And I use the following launch file: <node pkg = "cmvideo" type="cmvideo_node" name="cmvideo_node" ></node>

I know it's not a syntax problem, because the error message I get from the roslaunch is not from ros but from my executable file. Thank you for your help in advance!