Thread: newb: help with bool functions

hey everyone i am working on a tic tac toe game were i randomly generate a board when the user inputs a non negative number. so first i have to validate that the user actaully inputed a number and not a letter or a negative number. so far i cant get the program to recognize if the input is negative. but it will recognize if the input is a letter though.
here is my code

Code:

#include <stdio.h>
#include <time.h>
#include <stdbool.h>
#include <ctype.h>
void input(int* num1);


int main(void)
{
   int num1;   
   input(&num1);    
  
    return 0;
}

void input(int* num1)
{
   bool success = false;
   int scanres;
      

   printf("\nPlease enter a non-negative number seed: ");
   scanres = scanf("%d", &num1);
  
   if(scanres < 0)
     printf("\nYou entered a negative number.");
   else if (scanres == 1) 
      success = true;
   else if (scanres == 0)
      printf("\nNon-int data.");
   else       
      printf("\nEnd of data stream.");
  

   return ;
}

even though i have the if(scanres < 0)
for some reason it wont recogive that its negative and any negative number passes as true.
please help...the project is due wensday

ya i tried that

i just tried that and it still doesnt recogize that num1 is negative.

num1 is not an int.

how do i fix

Every time you want to think of the address of your number, it's just "num1", and every time you want the value of your number, it's "*num1".

i am still confused

num1 is not a number. It is the address of where a number lives. You cannot use num1 as a number and expect it to work.