Thread: scanf a null charactor

I am trying to update a file the user is asked to enter the new reorder level (integer) if they do not require to update this field they press enter. The code below is what i am using, it works if the customer enters a number, if they enter through the program fails at the scanf. Is there a way to get around this.


printf("\nWhat is the reorder level?");
fflush(stdin);
scanf("%d", &temp_s.reorderLevel);
if(temp_s.reorderLevel != NULL)
(*new_s).reorderLevel = temp_s.reorderLevel;

scanf("%d", &temp_s.reorderLevel);
if(temp_s.reorderLevel != NULL)
(*new_s).reorderLevel = temp_s.reorderLevel;

What is temp%s.reorderLevel?
If it's a pointer, then the scanf won't work(you try to save an integer %d to adress of pointer temp_s.reorderLevel,
and if it's an integer, then temp_s.reorderLevel != NULL is very queer compararison..

I think I didn't solve your problem because in my opinion you want this: if user press Enter, the default value will be used(e.g. last setting of reorderLevel). Maybe you can read a char, not an int, if user press Enter twice, you will get '\n' character so you know that user hit Enter. And if you get a digit, you can read the rest of the digits from input and then use a function like atoi().
It's complicated, so if someone know better solution, please post it here, it's quite interisting problem..