title: weird c function syntax
body: <p>I know my C up to this point. I was looking at the source files of PHP I downloaded, and I saw this strange syntax:</p>
  
  <pre><code>PHPAPI int php_printf(const char *format, ...)
  {
      // code...
  }
  </code></pre>
  
  <p>What does the <code>PHPAPI</code> do before the return type <code>int</code>? I've tried searching all over and I can't understand what this means. Is it a second return type? It can't be because the function does return an int. Maybe it extends to some other struct declared in a header file?</p>