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diff --git a/doc/html/boost/interprocess/weak_ptr.html b/doc/html/boost/interprocess/weak_ptr.html new file mode 100755 index 0000000000..2891564022 --- /dev/null +++ b/doc/html/boost/interprocess/weak_ptr.html @@ -0,0 +1,144 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Class template weak_ptr</title> +<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.76.1"> +<link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> +<link rel="up" href="../../boost_interprocess_reference.html#header.boost.interprocess.smart_ptr.weak_ptr_hpp" title="Header <boost/interprocess/smart_ptr/weak_ptr.hpp>"> +<link rel="prev" href="make_managed_unique_ptr.html" title="Function template make_managed_unique_ptr"> +<link rel="next" href="managed_weak_ptr.html" title="Struct template managed_weak_ptr"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> +<table cellpadding="2" width="100%"><tr> +<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td> +<td align="center"><a href="../../../../index.html">Home</a></td> +<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td> +<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> +<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> +<td align="center"><a href="../../../../more/index.htm">More</a></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="make_managed_unique_ptr.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../boost_interprocess_reference.html#header.boost.interprocess.smart_ptr.weak_ptr_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="managed_weak_ptr.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="refentry"> +<a name="boost.interprocess.weak_ptr"></a><div class="titlepage"></div> +<div class="refnamediv"> +<h2><span class="refentrytitle">Class template weak_ptr</span></h2> +<p>boost::interprocess::weak_ptr</p> +</div> +<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> +<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../../boost_interprocess_reference.html#header.boost.interprocess.smart_ptr.weak_ptr_hpp" title="Header <boost/interprocess/smart_ptr/weak_ptr.hpp>">boost/interprocess/smart_ptr/weak_ptr.hpp</a>> + +</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">,</span> <span class="keyword">typename</span> A<span class="special">,</span> <span class="keyword">typename</span> D<span class="special">></span> +<span class="keyword">class</span> <a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a> <span class="special">{</span> +<span class="keyword">public</span><span class="special">:</span> + <span class="comment">// types</span> + <span class="keyword">typedef</span> <span class="identifier">T</span> <a name="boost.interprocess.weak_ptr.element_type"></a><span class="identifier">element_type</span><span class="special">;</span> + <span class="keyword">typedef</span> <span class="identifier">T</span> <a name="boost.interprocess.weak_ptr.value_type"></a><span class="identifier">value_type</span><span class="special">;</span> + + <span class="comment">// <a class="link" href="weak_ptr.html#boost.interprocess.weak_ptrconstruct-copy-destruct">construct/copy/destruct</a></span> + <a class="link" href="weak_ptr.html#id994801-bb"><span class="identifier">weak_ptr</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> + <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Y<span class="special">></span> <a class="link" href="weak_ptr.html#id994812-bb"><span class="identifier">weak_ptr</span></a><span class="special">(</span><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a><span class="special"><</span> <span class="identifier">Y</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> + <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Y<span class="special">></span> <a class="link" href="weak_ptr.html#id994852-bb"><span class="identifier">weak_ptr</span></a><span class="special">(</span><a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a><span class="special"><</span> <span class="identifier">Y</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> + <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Y<span class="special">></span> weak_ptr& <a class="link" href="weak_ptr.html#id994892-bb"><span class="keyword">operator</span><span class="special">=</span></a><span class="special">(</span><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a><span class="special"><</span> <span class="identifier">Y</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> + <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Y<span class="special">></span> weak_ptr& <a class="link" href="weak_ptr.html#id994919-bb"><span class="keyword">operator</span><span class="special">=</span></a><span class="special">(</span><a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a><span class="special"><</span> <span class="identifier">Y</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> + + <span class="comment">// <a class="link" href="weak_ptr.html#id994705-bb">public member functions</a></span> + <a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a><span class="special"><</span> <span class="identifier">T</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <a class="link" href="weak_ptr.html#id994708-bb"><span class="identifier">lock</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> + <span class="keyword">long</span> <a class="link" href="weak_ptr.html#id994725-bb"><span class="identifier">use_count</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> + <span class="keyword">bool</span> <a class="link" href="weak_ptr.html#id994751-bb"><span class="identifier">expired</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> + <span class="keyword">void</span> <a class="link" href="weak_ptr.html#id994768-bb"><span class="identifier">reset</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> + <span class="keyword">void</span> <a class="link" href="weak_ptr.html#id994780-bb"><span class="identifier">swap</span></a><span class="special">(</span><span class="identifier">this_type</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> +<span class="special">}</span><span class="special">;</span></pre></div> +<div class="refsect1"> +<a name="id1840948"></a><h2>Description</h2> +<p>The <a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a> class template stores a "weak reference" to an object that's already managed by a <a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a>. To access the object, a <a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a> can be converted to a <a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a> using the <a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a> constructor or the member function lock. When the last <a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a> to the object goes away and the object is deleted, the attempt to obtain a <a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a> from the <a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a> instances that refer to the deleted object will fail: the constructor will throw an exception of type bad_weak_ptr, and weak_ptr::lock will return an empty <a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a>.</p> +<p>Every <a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a> meets the CopyConstructible and Assignable requirements of the C++ Standard Library, and so can be used in standard library containers. Comparison operators are supplied so that <a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a> works with the standard library's associative containers.</p> +<p><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a> operations never throw exceptions.</p> +<p>The class template is parameterized on T, the type of the object pointed to. </p> +<div class="refsect2"> +<a name="id1841061"></a><h3> +<a name="boost.interprocess.weak_ptrconstruct-copy-destruct"></a><code class="computeroutput">weak_ptr</code> + public + construct/copy/destruct</h3> +<div class="orderedlist"><ol class="orderedlist" type="1"> +<li class="listitem"> +<pre class="literallayout"><a name="id994801-bb"></a><span class="identifier">weak_ptr</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> +<p>Effects: Constructs an empty <code class="computeroutput"><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a></code>. Postconditions: use_count() == 0. </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Y<span class="special">></span> <a name="id994812-bb"></a><span class="identifier">weak_ptr</span><span class="special">(</span><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a><span class="special"><</span> <span class="identifier">Y</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <span class="keyword">const</span> <span class="special">&</span> r<span class="special">)</span><span class="special">;</span></pre> +<p>Effects: If r is empty, constructs an empty <code class="computeroutput"><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a></code>; otherwise, constructs a <code class="computeroutput"><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a></code> that shares ownership with r as if by storing a copy of the pointer stored in r.</p> +<p>Postconditions: use_count() == r.use_count().</p> +<p>Throws: nothing. </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Y<span class="special">></span> <a name="id994852-bb"></a><span class="identifier">weak_ptr</span><span class="special">(</span><a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a><span class="special"><</span> <span class="identifier">Y</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <span class="keyword">const</span> <span class="special">&</span> r<span class="special">)</span><span class="special">;</span></pre> +<p>Effects: If r is empty, constructs an empty <code class="computeroutput"><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a></code>; otherwise, constructs a <code class="computeroutput"><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a></code> that shares ownership with r as if by storing a copy of the pointer stored in r.</p> +<p>Postconditions: use_count() == r.use_count().</p> +<p>Throws: nothing. </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Y<span class="special">></span> weak_ptr& <a name="id994892-bb"></a><span class="keyword">operator</span><span class="special">=</span><span class="special">(</span><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a><span class="special"><</span> <span class="identifier">Y</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <span class="keyword">const</span> <span class="special">&</span> r<span class="special">)</span><span class="special">;</span></pre> +<p>Effects: Equivalent to weak_ptr(r).swap(*this).</p> +<p>Throws: nothing.</p> +<p>Notes: The implementation is free to meet the effects (and the implied guarantees) via different means, without creating a temporary. </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Y<span class="special">></span> weak_ptr& <a name="id994919-bb"></a><span class="keyword">operator</span><span class="special">=</span><span class="special">(</span><a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a><span class="special"><</span> <span class="identifier">Y</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <span class="keyword">const</span> <span class="special">&</span> r<span class="special">)</span><span class="special">;</span></pre> +<p>Effects: Equivalent to weak_ptr(r).swap(*this).</p> +<p>Throws: nothing.</p> +<p>Notes: The implementation is free to meet the effects (and the implied guarantees) via different means, without creating a temporary. </p> +</li> +</ol></div> +</div> +<div class="refsect2"> +<a name="id1841626"></a><h3> +<a name="id994705-bb"></a><code class="computeroutput">weak_ptr</code> public member functions</h3> +<div class="orderedlist"><ol class="orderedlist" type="1"> +<li class="listitem"> +<pre class="literallayout"><a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a><span class="special"><</span> <span class="identifier">T</span><span class="special">,</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">D</span> <span class="special">></span> <a name="id994708-bb"></a><span class="identifier">lock</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> +<p>Returns: expired()? shared_ptr<T>(): shared_ptr<T>(*this).</p> +<p>Throws: nothing. </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">long</span> <a name="id994725-bb"></a><span class="identifier">use_count</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> +<p>Returns: 0 if *this is empty; otherwise, the number of <code class="computeroutput"><a class="link" href="shared_ptr.html" title="Class template shared_ptr">shared_ptr</a></code> objects that share ownership with *this.</p> +<p>Throws: nothing.</p> +<p>Notes: use_count() is not necessarily efficient. Use only for debugging and testing purposes, not for production code. </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">bool</span> <a name="id994751-bb"></a><span class="identifier">expired</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> +<p>Returns: Returns: use_count() == 0.</p> +<p>Throws: nothing.</p> +<p>Notes: expired() may be faster than use_count(). </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">void</span> <a name="id994768-bb"></a><span class="identifier">reset</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> +<p>Effects: Equivalent to: weak_ptr().swap(*this). </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">void</span> <a name="id994780-bb"></a><span class="identifier">swap</span><span class="special">(</span><span class="identifier">this_type</span> <span class="special">&</span> other<span class="special">)</span><span class="special">;</span></pre> +<p>Effects: Exchanges the contents of the two smart pointers.</p> +<p>Throws: nothing. </p> +</li> +</ol></div> +</div> +</div> +</div> +<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> +<td align="left"></td> +<td align="right"><div class="copyright-footer">Copyright © 2005-2011 Ion Gaztanaga<p> + 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" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) + </p> +</div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="make_managed_unique_ptr.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../boost_interprocess_reference.html#header.boost.interprocess.smart_ptr.weak_ptr_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="managed_weak_ptr.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |