d>
</dl>
<dl><dt><b>Return values:</b></dt><dd>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td valign="top"></td><td valign="top"><em>TH_EFAULT</em>&nbsp;</td><td><em>_dec_ctx</em> or <em>_buf</em> is <code>NULL</code>. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>TH_EINVAL</em>&nbsp;</td><td><em>_buf_sz</em> is not <code>sizeof(int)</code>, or the post-processing level is out of bounds. The maximum post-processing level may be implementation-specific, and can be obtained 