Capture console output of a Python script from CAPL

Question

I am trying this Vector CANoe knowledge base article. I want to call a function from a Python module from inside a CAPL test module. But before that I want to run a simple Python script and capture console output of its execution.

Using sysExec and TestWaitForSyscall CAPL APIs I am able to execute the Python script. The test case also passes but I am not able to capture console output on Write window (basically "Hello World"). The APIs are only able to check the exit codes but I also want to be able to capture the console output as well.

Here is the example CAPL code that executes the Python script as a separate program and gets the result in form of exit code.

void MainTest ()
{
  CTC_CallPyScript();
}

testcase CTC_CallPyScript()
{
  long res;
  char absPath[256];
  
  getAbsFilePath("", absPath, elcount(absPath));
  write(absPath);
  res=testWaitForSyscall(absPath, "py HelloWorld.py", 0, 5000);
  if(res==1)
    testStepPass("Pass.");
  else
    testStepFail("Fail.");

}

I tried outputting into a text file like so but I don't see any file getting generated. Also I want to avoid this approach since file I/O is costly when making such calls frequently.

  res=testWaitForSyscall(absPath, "py HelloWorld.py > output.txt", 0, 5000);