In the EEROS library you will find a directory with examples. For this example see SubSystemTest.cpp.
Open a shell in the build directory of your EEROS library and run
$ sudo ./examples/system/subSystemTest
You have to run a program using real time threads with root privileges. We do not use the simulator in this example, hence there is no need to set the library path.
The example shows how a few blocks are packed into a subsystem which is used by a control system also using other blocks.