Thread: Loading a File into a linked list

Hi guys. I'm not really understanding how to do linked lists. I'm attempting to load a file into a linked list but I'm getting confused with the different pointers. Am I on the right track? What lines should I look over and change?

Code:

struct transaction
 {
    char itemName[20];
    int itemNumber, itemAmount;
    float itemPrice;
    struct transaction *nextPtr;
};
typedef struct transaction Item;

/*function LoadFile*/
Item* LoadFile(char*inputFile)
{
    int i;
    Item* tempPtr;
    Item* prevPtr;
    Item* currentPtr;
    File *fPtr = fopen(inputFile, "r");
while (!feof(fPtr))
    {
        printf("File has been loaded\n");
        scanf(fPtr, "%d", &itemNumber);

        currentPtr = NULL;
        prevPtr = NULL;
            for (i = 0; i<itemNumber; i++)
                {
                    fscanf(fPtr, "%d", &(temp->itemNumber));
                    fscanf(fPtr, "%s", temp->itemName);
                    fscanf(fPtr, "%d", &(temp->itemAmount));
                    fscanf(fPtr, "%d", &(temp->itemPrice));

                            if(currentPtr == NULL)
                            {
                                currentPtr = temp;
                            }
                            if(prevPtr != NULL)
                            {
                                prevPtr->nextPtr = tempPtr;
                            }
                                   tempPtr = tempPtr->nextPtr;
                }
fclose(fPtr)
}

There are some problems. for example:
itemNumber is a class member, the line

Code:

scanf(fPtr, "%d", &itemNumber);

is wrong.
you need to allocate memory for one Item and then use its data to put stuff in.
e.g.

Code:

Item * tempPtr = (Item * )malloc (sizeof(Item));
if (tempPtr == NULL){
   // do some error;
}

and then when you want to use you should do:

Code:

scanf(fPtr, "%d", &(tempPtr->itemNumber));

Also, you assume a lot about the file content structure, be careful..