title: Portably include GLib headers in autoconf/automake
body: <p>I need to include the <a href="http://en.wikipedia.org/wiki/GLib" rel="nofollow noreferrer">GLib</a> headers for a project that is built with an autoconf-based system for portability.</p>
  
  <p>How can I safely import the GLib headers in a portable manner? I know about <a href="http://en.wikipedia.org/wiki/Pkg-config" rel="nofollow noreferrer">pkg-config</a>, but that is not entirely portable (since some systems don't have it and I would prefer to only rely on autoconf for configuration).</p>