title: How to define NULL using #define
body: <p>I want to redefine NULL in my program such as </p>
  
  <pre><code>#define MYNULL ((void*)0)
  </code></pre>
  
  <p>But this definition is not working in the following statement:</p>
  
  <pre><code>char *ch = MYNULL;
  </code></pre>
  
  <blockquote>
    <blockquote>
      <p>Error : can not convert from void* to char *</p>
    </blockquote>
  </blockquote>
  
  <p>What would be the best way to define NULL?</p>