.
    </TR>
</TABLE>

<A NAME="optimal_buffer_size"></A>
<PRE CLASS="broken_ie"><SPAN CLASS="keyword">template</SPAN>&lt;<SPAN CLASS="keyword">typename</SPAN> T&gt;
std::streamsize optimal_buffer_size(T&amp; t);</PRE>

<P>The semantics of <CODE>optimal_buffer_size</CODE> depends on the <A HREF="../guide/traits.html#category">category</A> of <CODE>T</CODE> as follows:</P>

<TABLE STYLE="margin-left:2em;margin-bottom:2em" BORDER=1 CELLPADDING=4>
    <TR><TH><CODE>category_of&lt;T&gt;::type</CODE></TH><TH>sema