1  struct foo {
       2  	int a;
       3  	int b;
       4  };
       5  
       6  int func(struct foo *foo, int a)
       7  {
       8  	if (foo->b == 0) {
       9  		int ret = foo->a = a;
      10  		if (a >= 0)
      11  			foo->a = a;
      12  		return (ret);
      13   	}
      14  	return (0);
      15  }