Thread: Crash on NULL

Hi, can someone explain to me why de following code does crash the program after it reached the NULL pointer????

the max value of Searchvalue = 5 but when i make it 6 it crashes my program.

Code:

struct parkinglot* FindParkingLot (struct parkinglot* StartPtr, int SearchValue)
{		                            // start at head of the list
     struct parkinglot* HuidigePtr = StartPtr;
     while (HuidigePtr != NULL && HuidigePtr->Vak != SearchValue)  {
            HuidigePtr = HuidigePtr->VolgendePtr;
     }
     if (HuidigePtr->Vak != SearchValue)
        return (NULL);
     else 
        return (HuidigePtr);
};

regards Fred

EDIT: Oops, wrong code. Perhaps tabstop's or anon's suggestion is better.

This should also work. After the loop HuidigePtr will either be NULL or point to the found node.

Code:

struct parkinglot* FindParkingLot (struct parkinglot* StartPtr, int SearchValue)
{		                            // start at head of the list
     struct parkinglot* HuidigePtr = StartPtr;
     while (HuidigePtr != NULL && HuidigePtr->Vak != SearchValue)  {
            HuidigePtr = HuidigePtr->VolgendePtr;
     }
     return (HuidigePtr);
};