Where does `getchar()` store the user input?

Question

I\'ve started reading \"The C Programming Language\" (K&R) and I have a doubt about the getchar() function.

For example this code:

#         


        

Answer 1

the code is functionally equivalent to

main(){
  int c;
  c = getchar();
  while(c != EOF) {
    putchar(c);
    c = getchar();
  }
}

you might find this version easier to understand. the only reason to put the assignment in the conditional is to avoid having to type 'c=getchar()' twice.