acks</i></dt>
<dd>A completed <a href="ov_callbacks.html">ov_callbacks</a> struct which indicates desired custom file manipulation routines.  vorbisfile.h defines several preprovided callback sets; see <a href="ov_callbacks.html">ov_callbacks</a> for details.</dd>
</dl>


<h3>Return Values</h3>
<blockquote>
<li>0 for success</li>
<li>less than zero for failure:</li>
<ul>
<li>OV_EREAD - A read from media returned an error.</li>
<li>OV_ENOTVORBIS - Bitstream does not contain any Vorbis data.</li>
<li>OV_EVERS