returning a string - random unit testing [duplicate]

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• Can a local variable's memory be accessed outside its scope? 18 answers

I am creating a unit test harness for my program and I want the harness to test randomly each run.

The PROBLEM:

I am having trouble returning a string. This is a school assignment as well. I'm looking for some advice and guidance.

The function "stringOptions" is not able to return a string correctly to pass through into the "assessGrade" function.

Here's some code snipits:

int main (void)
{
  int testNumber = 1; // forcing it to choose the first option for testing purposes
  char* stringPtr = NULL;
  double finalGrade = 0;

  stringPtr = stringOptions(testNumber);
  finalGrade = assessGrade(stringGrade); // assesGrade takes a string and returns a double as the result
  studentGradeCondition(finalGrade); // prints out the student's resulting grade


  return 0;
}


char * stringOptions (int randomNum)
{
  char incomplete[2] = "I";
  if (randomNum == 1)
  {
    return incomplete;
  }
}

I have a random number generator creating different number and normally "stringOptions" will have all the different type of string that could be tested.