How do I reverse a string using pointer and recursion, C Programming ?

int ReverseString(char *, int, int);
int main(void){
  char string[10] = "abcdefghi";
  ReverseString(string, 0, strlen(string)-1);
  printf("%s\n",string);
  return 0;
}

int ReverseString(char *str, int front, int end){
  if(front > end)
    return 1;
  else{
    char temp;
    temp = str[front];
    str[front] = str[end];
    str[end] = temp;
    front++;
    end--;
    ReverseString(str, front, end);
  }
}