title: Two Equal Signs in One Line?
body: <p>Could someone please explain what this does and how it is legal C code?  I found this line in this code: <a href="http://code.google.com/p/compression-code/downloads/list" rel="noreferrer">http://code.google.com/p/compression-code/downloads/list</a>, which is a C implementation of the Vitter algorithm for <a href="http://en.wikipedia.org/wiki/Adaptive_Huffman_coding" rel="noreferrer">Adaptive Huffman Coding</a></p>
  
  <pre><code>ArcChar = ArcBit = 0;
  </code></pre>
  
  <p>From the function:</p>
  
  <pre><code>void arc_put1 (unsigned bit)
  {
      ArcChar &lt;&lt;= 1;
  
      if( bit )
          ArcChar |= 1;
  
      if( ++ArcBit &lt; 8 )
          return;
  
      putc (ArcChar, Out);
      ArcChar = ArcBit = 0;
  }
  </code></pre>
  
  <p>ArcChar is an <code>int</code> and ArcBit is an <code>unsigned char</code></p>