t be used to manipulate the face.</p>
<p>&lsquo;value&rsquo; is a void pointer because the values returned can be of various types.</p>
<p>If either &lsquo;value&rsquo; is NULL or &lsquo;value_len&rsquo; is too small, just the required memory size for the requested entry is returned.</p>
<p>The &lsquo;idx&rsquo; parameter is used, not only to retrieve elements of, for example, the FontMatrix or FontBBox, but also to retrieve name keys from the CharStrings dictionary, and the charstrings themselves. It is ig