Making an int into a char* (string) Part 2

Well, I've got it.  Turns out what I had before isn't probably the best way to code a function for that, since C apparently doesn't like functions returning char* and will refuse to work right if you do.

So here we have a function that requires both the integer holding the number and the string that the number is to be inserted into as parameters. It will return 1 if it was successful and 0 if it wasn't.

int my_itoa(char* str, int num) {
  int i, digit, neg = 0, length = 1, x = 0;
 
  if(str != NULL) {
    if(num < 0) {
      neg = num;
      num = -num;
    }
    for(i = num / 10; i > 0 ; i /= 10) {
      length++;
    }
    for(i = length - 1; i >= 0; i--) {
      if(neg < 0) {
        str[0] = '-';
        neg = 1;
      }
      digit = num % 10;
      str[i + neg] = digit + '0';
      num /= 10;
    }
    str[length + neg] = '\0';
    x = 1;
  }
  return x;
}

 Because I didn't want the function to require any libraries, all it can really check for is if the char* pointer is actually pointing to something.