Investigate usage of vtkSocket API to send and receive messages asynchronously.
Build
$ export RXCPP_DIR=/path/to/rxcpp/source
$ export VTK_DIR=/path/to/vtk/build
$ mkdir build && cd build && cmake -GNinja -S ../ -B .
$ ninja
Run
Launch in server mode.
$ ./main -s 1234
Launch in client mode and connect to the server we created above.
$ ./main -c localhost 1234 -n20
Here, the -n argument specifies no. of remote commands to issue.
In server mode, three services are emulated: a data, render and io service that simply print the commands. A client picks a message at random and sends it to a random destination service on the server.
Sample output (server):
$ ./main -s 1234
( 0.000s) [main thread ] main.cxx:233 INFO| => Waiting for connection: localhost:1234
( 2.528s) [main thread ] main.cxx:236 INFO| => Client connected!
( 2.528s) [main thread ] main.cxx:187 INFO| => Registered services.data:14752253762927134915
( 2.528s) [main thread ] main.cxx:187 INFO| => Registered services.render:15335038379579459937
( 2.528s) [main thread ] main.cxx:187 INFO| => Registered services.io:15497323717503977043
( 2.528s) [main thread ] main.cxx:252 INFO| => Advertise service registry
( 2.539s) [services.render ] main.cxx:170 INFO| render-4
( 2.539s) [services.io ] main.cxx:170 INFO| write-2
( 2.539s) [services.render ] main.cxx:170 INFO| render-3
( 2.539s) [services.render ] main.cxx:170 INFO| render-3
( 2.539s) [services.data ] main.cxx:170 INFO| object-delete
( 2.539s) [services.io ] main.cxx:170 INFO| read
( 2.539s) [services.render ] main.cxx:170 INFO| render
( 2.539s) [services.data ] main.cxx:170 INFO| update-state
( 2.539s) [services.data ] main.cxx:170 INFO| object-delete
( 2.539s) [services.render ] main.cxx:170 INFO| render-4
( 2.539s) [services.data ] main.cxx:170 INFO| object-delete
( 2.539s) [services.data ] main.cxx:170 INFO| object-delete
( 2.539s) [services.render ] main.cxx:170 INFO| render-4
( 2.539s) [services.render ] main.cxx:170 INFO| render
( 2.539s) [services.render ] main.cxx:170 INFO| render-2
( 2.539s) [services.render ] main.cxx:170 INFO| render
( 2.539s) [services.io ] main.cxx:170 INFO| read-2
( 2.539s) [services.data ] main.cxx:170 INFO| update-state
( 2.539s) [services.render ] main.cxx:170 INFO| render-2
( 2.539s) [services.io ] main.cxx:170 INFO| write-2
( 3.539s) [main thread ] main.cxx:343 INFO| => Shutdown services
( 3.539s) [services.io ] main.cxx:176 INFO| exit
( 3.539s) [services.data ] main.cxx:176 INFO| exit
( 3.539s) [services.render ] main.cxx:176 INFO| exit
( 3.539s) [main thread ] main.cxx:349 INFO| => Shutdown comm
( 3.539s) [comm.send ] main.cxx:96 INFO| exit
( 3.539s) [comm.recv ] main.cxx:141 INFO| exit
( 3.539s) [main thread ] main.cxx:357 INFO| Wait for client to disconnect
( 3.640s) [main thread ] main.cxx:361 INFO| => Shutdown server
Sample output (client):
$ ./main -c localhost 1234 -n20
( 0.000s) [main thread ] main.cxx:242 INFO| => Connected to localhost:1234
( 0.000s) [main thread ] main.cxx:265 INFO| => Receiving service registry
( 0.000s) [main thread ] main.cxx:279 INFO| => services.data:14752253762927134915
( 0.000s) [main thread ] main.cxx:279 INFO| => services.io:15497323717503977043
( 0.000s) [main thread ] main.cxx:279 INFO| => services.render:15335038379579459937
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render-4
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: write-2
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render-3
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render-3
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: object-delete
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: read
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: update-state
( 0.010s) [main thread ] main.cxx:73 INFO| => Enqueue msg: object-delete
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render-4
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: object-delete
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: object-delete
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render-4
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render-2
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: read-2
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: update-state
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: render-2
( 0.011s) [main thread ] main.cxx:73 INFO| => Enqueue msg: write-2
( 1.011s) [main thread ] main.cxx:343 INFO| => Shutdown services
( 1.011s) [main thread ] main.cxx:349 INFO| => Shutdown comm
( 1.011s) [comm.send ] main.cxx:96 INFO| exit
( 1.012s) [comm.recv ] main.cxx:141 INFO| exit
( 1.012s) [main thread ] main.cxx:364 INFO| => Shutdown client