title: sizeof a struct member
body: <p>How can I get the size of a member in a struct in C?</p>
  
  <pre><code>struct A
  {
          char arr[64];
  };
  </code></pre>
  
  <p>i need something like that:</p>
  
  <p>sizeof(A::arr)</p>
  
  <p>thanks</p>