ceph/src/boost/libs/iostreams/doc/functions/tee.html

   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>&lt;boost/iostreams/tee.hpp&gt;</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>&lt;<SPAN CLASS='keyword'>typename</SPAN> <A CLASS='documented' HREF='#tee_filter_template_params'>Sink</A>&gt;
  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&lt;Sink&gt;::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&amp; snk);
  58
  59     <SPAN CLASS='comment'>// OutputFilter member functions</SPAN>
  60 };
  61
  62 <SPAN CLASS='keyword'>template</SPAN>&lt;<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>&gt;
  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&lt;Sink1&gt;::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>&amp; sink1, [<SPAN CLASS='keyword'>const</SPAN>] Sink2&amp; sink2);
  69
  70     <SPAN CLASS='comment'>// Sink member functions</SPAN>
  71 };
  72
  73 <SPAN CLASS='keyword'>template</SPAN>&lt;<SPAN CLASS='keyword'>typename</SPAN> <A CLASS='documented' HREF='#tee_unary_template_params'>Sink</A>&gt;
  74 <A CLASS='documented' HREF='#tee_filter'>tee_filter</A>&lt;Sink&gt; <A CLASS='documented' HREF='#tee_unary'>tee</A>([<SPAN CLASS='keyword'>const</SPAN>] Sink&amp; snk);
  75
  76 <SPAN CLASS='keyword'>template</SPAN>&lt;<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>&gt;
  77 <A CLASS='documented' HREF='#tee_device'>tee_device</A>&lt;Sink1, Sink2&gt; <A CLASS='documented' HREF='#tee_binary'>tee</A>([<SPAN CLASS='keyword'>const</SPAN>] Sink1&amp; sink1, [<SPAN CLASS='keyword'>const</SPAN>] Sink2&amp; 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&amp; 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>&amp; sink1, [<SPAN CLASS='keyword'>const</SPAN>] Sink2&amp; 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>&lt;<SPAN CLASS='keyword'>typename</SPAN> Sink&gt;
 145 tee_filter&lt;Sink&gt; tee([<SPAN CLASS='keyword'>const</SPAN>] Sink&amp; 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>&lt;<SPAN CLASS='keyword'>typename</SPAN> Sink1, <SPAN CLASS='keyword'>typename</SPAN> Sink2&gt;
 163 tee_device&lt;Sink1, Sink2&gt; tee([<SPAN CLASS='keyword'>const</SPAN>] Sink1&amp; sink1, [<SPAN CLASS='keyword'>const</SPAN>] Sink2&amp; 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">&copy; Copyright 2008 <a href="http://www.coderage.com/" target="_top">CodeRage, LLC</a><br/>&copy; Copyright 2004-2007 <a href="http://www.coderage.com/turkanis/" 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>