lass="parameter"><code>program</code></em> should have previously been the
	target of a call to
	<a class="citerefentry" href="glLinkProgram"><span class="citerefentry"><span class="refentrytitle">glLinkProgram</span></span></a>,
	but it is not necessary for it to have been linked
	successfully.</p><p>The size of the character buffer required to store the
	longest attribute variable name in
	<em class="parameter"><code>program</code></em> can be obtained by calling
	<a class="citerefentry" href="glGetProgra