1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 2<HTML> 3<HEAD> 4 <TITLE>Function Template tee</TITLE> 5 <LINK REL="stylesheet" HREF="../../../../boost.css"> 6 <LINK REL="stylesheet" HREF="../theme/iostreams.css"> 7</HEAD> 8<BODY> 9 10<!-- Begin Banner --> 11 12 <H1 CLASS="title">Function Template <CODE>tee</CODE></H1> 13 <HR CLASS="banner"> 14 15<!-- End Banner --> 16 17<DL class="page-index"> 18 <DT><A href="#description">Description</A></DT> 19 <DT><A href="#headers">Headers</A></DT> 20 <DT><A href="#reference">Reference</A></DT> 21</DL> 22 23<HR> 24 25<A NAME="description"></A> 26<H2>Description</H2> 27 28<P> 29 The class templates <CODE>tee_filter</CODE> and <CODE>tee_device</CODE> provide two ways to split an output sequence so that all data is directed simultaneously to two different locations. A <CODE>tee_filter</CODE> is an <A HREF="../concepts/output_filter.html">OutputFilter</A> which copies all data to a <A HREF="../concepts/sink.html">Sink</A> specified at construction in addition to passing it downstream unmodified. A <CODE>tee_device</CODE> is a <A HREF="../concepts/sink.html">Sink</A> which copies all data to two Sinks specified at construction. 30</P> 31 32<P> 33 The overloaded function template <A HREF='#tee'><CODE>tee</CODE></A> is an <A HREF='http://www.boost.org/more/generic_programming.html#object_generator' TARGET='_top'>object generator</A> which given a Sink or a pair of Sinks returns an appropriate specialization of <CODE>tee_filter</CODE> or <CODE>tee_device</CODE>. 34</P> 35 36<A NAME="headers"></A> 37<H2>Headers</H2> 38 39<DL class="page-index"> 40 <DT><A CLASS="header" HREF="../../../../boost/iostreams/tee.hpp"><CODE><boost/iostreams/tee.hpp></CODE></A></DT> 41</DL> 42 43<A NAME="reference"></A> 44<H2>Reference</H2> 45 46<A NAME="synopsis"></A> 47<H4>Synopsis</H4> 48 49<PRE CLASS="broken_ie"><SPAN CLASS="keyword">namespace</SPAN> boost { <SPAN CLASS="keyword">namespace</SPAN> iostreams { 50 51<SPAN CLASS='keyword'>template</SPAN><<SPAN CLASS='keyword'>typename</SPAN> <A CLASS='documented' HREF='#tee_filter_template_params'>Sink</A>> 52<SPAN CLASS='keyword'>class</SPAN> <A CLASS='documented' HREF='#tee_filter'>tee_filter</A> { 53<SPAN CLASS='keyword'>public:</SPAN> 54 <SPAN CLASS='keyword'>typedef</SPAN> <SPAN CLASS='keyword'>typename</SPAN> char_type_of<Sink>::type char_type; 55 <SPAN CLASS='keyword'>typedef</SPAN> <SPAN CLASS='omitted'>[implementation-defined]</SPAN> category; 56 57 <SPAN CLASS='keyword'>explicit</SPAN> <A CLASS='documented' HREF='#tee_filter_ctor'>tee_filter</A>([<SPAN CLASS='keyword'>const</SPAN>] Sink& snk); 58 59 <SPAN CLASS='comment'>// OutputFilter member functions</SPAN> 60}; 61 62<SPAN CLASS='keyword'>template</SPAN><<SPAN CLASS='keyword'>typename</SPAN> <A CLASS='documented' HREF='#tee_device_template_params'>Sink1</A>, <SPAN CLASS='keyword'>typename</SPAN> <A CLASS='documented' HREF='#tee_device_template_params'>Sink2</A>> 63<SPAN CLASS='keyword'>class</SPAN> <A CLASS='documented' HREF='#tee_device'>tee_device</A> { 64<SPAN CLASS='keyword'>public:</SPAN> 65 <SPAN CLASS='keyword'>typedef</SPAN> <SPAN CLASS='keyword'>typename</SPAN> char_type_of<Sink1>::type char_type; 66 <SPAN CLASS='keyword'>typedef</SPAN> <SPAN CLASS='omitted'>[implementation-defined]</SPAN> category; 67 68 <A CLASS='documented' HREF='#tee_device_ctor'>tee_device</A>([<SPAN CLASS='keyword'>const</SPAN>] <SPAN CLASS='keyword'>const</SPAN>& sink1, [<SPAN CLASS='keyword'>const</SPAN>] Sink2& sink2); 69 70 <SPAN CLASS='comment'>// Sink member functions</SPAN> 71}; 72 73<SPAN CLASS='keyword'>template</SPAN><<SPAN CLASS='keyword'>typename</SPAN> <A CLASS='documented' HREF='#tee_unary_template_params'>Sink</A>> 74<A CLASS='documented' HREF='#tee_filter'>tee_filter</A><Sink> <A CLASS='documented' HREF='#tee_unary'>tee</A>([<SPAN CLASS='keyword'>const</SPAN>] Sink& snk); 75 76<SPAN CLASS='keyword'>template</SPAN><<SPAN CLASS='keyword'>typename</SPAN> <A CLASS='documented' HREF='#tee_binary_template_params'>Sink1</A>, <SPAN CLASS='keyword'>typename</SPAN> <A CLASS='documented' HREF='#tee_binary_template_params'>Sink2</A>> 77<A CLASS='documented' HREF='#tee_device'>tee_device</A><Sink1, Sink2> <A CLASS='documented' HREF='#tee_binary'>tee</A>([<SPAN CLASS='keyword'>const</SPAN>] Sink1& sink1, [<SPAN CLASS='keyword'>const</SPAN>] Sink2& sink2); 78 79 80} } // End namespace boost::io</PRE> 81 82<A NAME="tee_filter"></A> 83<H2>Class Template <CODE>tee_filter</CODE></H2> 84 85<H4>Description</H4> 86 87<P>An <A HREF='../concepts/output_filter.html'>OutputFilter</A> which copies all data which passes through it to a <A HREF='../concepts/sink.html'>Sink</A> specified at construction. A <CODE>tee_filter</CODE> is <A HREF='../concepts/closable.html'>Closable</A>, <A HREF='../concepts/flushable.html'>Flushable</A>, <A HREF='../concepts/localizable.html'>Localizable</A> and <A HREF='../concepts/optimally_buffered.html'>OptimallyBuffered</A>.</P> 88 89<A NAME="tee_filter_template_params"></A> 90<H4>Template parameters</H4> 91 92<TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2> 93<TR> 94 <TR> 95 <TD VALIGN="top"><I>Sink</I></TD><TD WIDTH="2em" VALIGN="top">-</TD> 96 <TD>A <A HREF='../concepts/blocking.html'>Blocking</A> <A HREF='../concepts/sink.html'>Sink</A></TD> 97 </TR> 98</TABLE> 99 100<A NAME="tee_filter_ctor"></A> 101<H4><CODE>tee_filter::tee_filter</CODE></H4> 102 103<PRE CLASS="broken_ie"><SPAN CLASS='keyword'>explicit</SPAN> tee_filter([<SPAN CLASS='keyword'>const</SPAN>] Sink& sink);</PRE> 104 105<P> 106 Constructs an instance of <CODE>tee_filter</CODE> based on the given Sink. The function parameter is a non-<CODE>const</CODE> reference if <CODE>Sink</CODE> is a stream or stream buffer type, and a <CODE>const</CODE> reference otherwise. 107</P> 108 109<A NAME="tee_device"></A> 110<H2>Class Template <CODE>tee_device</CODE></H2> 111 112<H4>Description</H4> 113 114<P>A <A HREF='../concepts/sink.html'>Sink</A> which copies all data to each of two Sinks specified at construction. A <CODE>tee_device</CODE> is <A HREF='../concepts/closable.html'>Closable</A>, <A HREF='../concepts/flushable.html'>Flushable</A>, <A HREF='../concepts/localizable.html'>Localizable</A> and <A HREF='../concepts/optimally_buffered.html'>OptimallyBuffered</A>.</P> 115 116<A NAME="tee_device_template_params"></A> 117<H4>Template parameters</H4> 118 119<TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2> 120<TR> 121 <TR> 122 <TD VALIGN="top"><I>Sink1</I></TD><TD WIDTH="2em" VALIGN="top">-</TD> 123 <TD>A <A HREF='../concepts/blocking.html'>Blocking</A> <A HREF='../concepts/sink.html'>Sink</A></TD> 124 </TR> 125 <TR> 126 <TD VALIGN="top"><I>Sink2</I></TD><TD WIDTH="2em" VALIGN="top">-</TD> 127 <TD>A <A HREF='../concepts/blocking.html'>Blocking</A> <A HREF='../concepts/sink.html'>Sink</A> with the same <A HREF='../guide/traits.html#char_type'>character type</A> as <I>Sink1</I></TD> 128 </TR> 129</TABLE> 130 131<A NAME="tee_device_ctor"></A> 132<H4><CODE>tee_device::tee_device</CODE></H4> 133 134<PRE CLASS="broken_ie">tee_device([<SPAN CLASS='keyword'>const</SPAN>] <SPAN CLASS='keyword'>const</SPAN>& sink1, [<SPAN CLASS='keyword'>const</SPAN>] Sink2& sink2);</PRE> 135 136<P> 137 Constructs an instance of <CODE>tee_device</CODE> based on the given pair of Sinks. Each function parameter is a non-<CODE>const</CODE> reference if the corresponding template argument is a stream or stream buffer type, and a <CODE>const</CODE> reference otherwise. 138</P> 139 140<A NAME="tee"></A> 141<A NAME="tee_unary"></A> 142<H2>Function Template <CODE>tee</CODE></H2> 143 144<PRE CLASS="broken_ie"><SPAN CLASS='keyword'>template</SPAN><<SPAN CLASS='keyword'>typename</SPAN> Sink> 145tee_filter<Sink> tee([<SPAN CLASS='keyword'>const</SPAN>] Sink& snk);</PRE> 146 147<A NAME="tee_unary_template_params"></A> 148<H4>Template parameters</H4> 149<TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2> 150<TR> 151 <TR> 152 <TD VALIGN="top"><I>Sink</I></TD><TD WIDTH="2em" VALIGN="top">-</TD> 153 <TD>A <A HREF='../concepts/blocking.html'>Blocking</A> <A HREF='../concepts/sink.html'>Sink</A></TD> 154 </TR> 155</TABLE> 156 157<P> 158 Constructs an instance of an appropriate specialization of <CODE>tee_filter</CODE> based on the given Sink. The function parameter is a non-<CODE>const</CODE> reference if <CODE>Sink</CODE> is a stream or stream buffer type, and a <CODE>const</CODE> reference otherwise. 159</P> 160 161<A NAME="tee_binary"></A> 162<PRE CLASS="broken_ie"><SPAN CLASS='keyword'>template</SPAN><<SPAN CLASS='keyword'>typename</SPAN> Sink1, <SPAN CLASS='keyword'>typename</SPAN> Sink2> 163tee_device<Sink1, Sink2> tee([<SPAN CLASS='keyword'>const</SPAN>] Sink1& sink1, [<SPAN CLASS='keyword'>const</SPAN>] Sink2& sink2);</PRE> 164 165<A NAME="tee_binary_template_params"></A> 166<H4>Template parameters</H4> 167<TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2> 168<TR> 169 <TR> 170 <TD VALIGN="top"><I>Sink1</I></TD><TD WIDTH="2em" VALIGN="top">-</TD> 171 <TD>A <A HREF='../concepts/blocking.html'>Blocking</A> <A HREF='../concepts/sink.html'>Sink</A></TD> 172 </TR> 173 <TR> 174 <TD VALIGN="top"><I>Sink2</I></TD><TD WIDTH="2em" VALIGN="top">-</TD> 175 <TD>A <A HREF='../concepts/blocking.html'>Blocking</A> <A HREF='../concepts/sink.html'>Sink</A></TD> 176 </TR> 177</TABLE> 178 179<P> 180 Constructs an instance of an appropriate specialization of <CODE>tee_device</CODE> based on the given pair of Sinks. Each function parameter is a non-<CODE>const</CODE> reference if the corresponding template argument is a stream or stream buffer type, and a <CODE>const</CODE> reference otherwise. 181</P> 182 183<!-- Begin Footer --> 184 185<HR> 186 187<P CLASS="copyright">© Copyright 2008 <a href="http://www.coderage.com/" target="_top">CodeRage, LLC</a><br/>© Copyright 2004-2007 <a href="https://www.boost.org/users/people/jonathan_turkanis.html" target="_top">Jonathan Turkanis</a></P> 188<P CLASS="copyright"> 189 Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at <A HREF="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</A>) 190</P> 191 192<!-- End Footer --> 193 194</BODY> 195