omplete</A>, <CODE>pop</CODE> causes each Filter and Device in the chain to be closed using the function <A HREF="../functions/close.html"><CODE>close</CODE></A>, unless the auto-close feature has been disabled using <A HREF='#set_auto_close'><CODE>set_auto_clos</CODE></A>.</P>

<A NAME="empty"></A>
<H4><CODE>chain::empty</CODE></H4>
<PRE CLASS="broken_ie">    <SPAN CLASS="keyword">bool</SPAN> empty() <SPAN CLASS="keyword">const</SPAN>;</PRE>

<P>Returns <CODE>true</CODE> if this chain contains no Filters o