How to work with the output of another ECU

Question

I am new in CAPL (CANoe). I have 2 Nodes here; CAN_Portscanner that scans a vehicle and returns 47 ECUs and their services and a Diagnostic Tester that i want to develop. it has to recognize only a few ECUs from the Portscanner. When I find the service, I need to send a service request to an ECU and extend the ECU function with a response in CANoe to know that my request was successful.

I need to read a message from another .can file and work with it. I tried something like this:

includes
{
  #include "CAN_Portscanner.can"
}

variables
{
  int counter;
}

void MainTest()
{
  while(diagnose_request_msg.ID <= 0x7E1)
  {
    counter++;
  }
  write("Number of ECUs in the Tester: %d",counter);
}

I don't know if the #include is correct and why do i obtain a warning about MainTest.

Warning 2033 at (12,1): Use of function 'MainTest' seems to indicate that this file should be a test module or test unit. Diagnostic Tester.can