Initializing Var with Scanf()

Question

Why is this not working:

long int input = scanf("%ld",&input);

Is it forbidden to define a var this way?!

Answer 1

scanf("%ld", &input); is fine, but long int input = scanf("%ld", &input); makes you get an value you don't expect.
You can do:
long int input = 0;
scanf("ld", &input);

Answer 2

I am not sure about this, but I reckon that you can’t use the word input as a variable name. probably a reserved name.
several languages have this

Answer 3

@Brave Tea Nope - thats not the case

Answer 4

Yep, i know. The question is: why?