title: C , Error: Expression must be a modifiable lvalue
body: <p>i have the following code:</p>
  
  <pre><code>#define NULL ((void*)0)
  void* Globalptr = NULL;
  void func(ptrtype* input)
  {
   ((ptrtype*)Globalptr) = input;
  }
  </code></pre>
  
  <p>I get Error on line <code>((ptrtype*)Globalptr) = input;</code> says " expression must be a modifiable lvalue"</p>