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diff --git a/gcc-4.4.3/libstdc++-v3/doc/html/manual/auto_ptr.html b/gcc-4.4.3/libstdc++-v3/doc/html/manual/auto_ptr.html deleted file mode 100644 index 9da480093..000000000 --- a/gcc-4.4.3/libstdc++-v3/doc/html/manual/auto_ptr.html +++ /dev/null @@ -1,90 +0,0 @@ -<?xml version="1.0" encoding="UTF-8" standalone="no"?> -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> -<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>auto_ptr</title><meta name="generator" content="DocBook XSL Stylesheets V1.74.0" /><meta name="keywords" content=" ISO C++ , auto_ptr " /><meta name="keywords" content=" ISO C++ , library " /><link rel="home" href="../spine.html" title="The GNU C++ Library Documentation" /><link rel="up" href="memory.html" title="Chapter 11. Memory" /><link rel="prev" href="memory.html" title="Chapter 11. Memory" /><link rel="next" href="shared_ptr.html" title="shared_ptr" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">auto_ptr</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="memory.html">Prev</a> </td><th width="60%" align="center">Chapter 11. Memory</th><td width="20%" align="right"> <a accesskey="n" href="shared_ptr.html">Next</a></td></tr></table><hr /></div><div class="sect1" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.util.memory.auto_ptr"></a>auto_ptr</h2></div></div></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="auto_ptr.limitations"></a>Limitations</h3></div></div></div><p>Explaining all of the fun and delicious things that can - happen with misuse of the <code class="classname">auto_ptr</code> class - template (called <acronym class="acronym">AP</acronym> here) would take some - time. Suffice it to say that the use of <acronym class="acronym">AP</acronym> - safely in the presence of copying has some subtleties. - </p><p> - The AP class is a really - nifty idea for a smart pointer, but it is one of the dumbest of - all the smart pointers -- and that's fine. - </p><p> - AP is not meant to be a supersmart solution to all resource - leaks everywhere. Neither is it meant to be an effective form - of garbage collection (although it can help, a little bit). - And it can <span class="emphasis"><em>not</em></span>be used for arrays! - </p><p> - <acronym class="acronym">AP</acronym> is meant to prevent nasty leaks in the - presence of exceptions. That's <span class="emphasis"><em>all</em></span>. This - code is AP-friendly: - </p><pre class="programlisting"> - // Not a recommend naming scheme, but good for web-based FAQs. - typedef std::auto_ptr<MyClass> APMC; - - extern function_taking_MyClass_pointer (MyClass*); - extern some_throwable_function (); - - void func (int data) - { - APMC ap (new MyClass(data)); - - some_throwable_function(); // this will throw an exception - - function_taking_MyClass_pointer (ap.get()); - } - </pre><p>When an exception gets thrown, the instance of MyClass that's - been created on the heap will be <code class="function">delete</code>'d as the stack is - unwound past <code class="function">func()</code>. - </p><p>Changing that code as follows is not <acronym class="acronym">AP</acronym>-friendly: - </p><pre class="programlisting"> - APMC ap (new MyClass[22]); - </pre><p>You will get the same problems as you would without the use - of <acronym class="acronym">AP</acronym>: - </p><pre class="programlisting"> - char* array = new char[10]; // array new... - ... - delete array; // ...but single-object delete - </pre><p> - AP cannot tell whether the pointer you've passed at creation points - to one or many things. If it points to many things, you are about - to die. AP is trivial to write, however, so you could write your - own <code class="code">auto_array_ptr</code> for that situation (in fact, this has - been done many times; check the mailing lists, Usenet, Boost, etc). - </p></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="auto_ptr.using"></a>Use in Containers</h3></div></div></div><p> - </p><p>All of the <a class="ulink" href="../23_containers/howto.html" target="_top">containers</a> - described in the standard library require their contained types - to have, among other things, a copy constructor like this: - </p><pre class="programlisting"> - struct My_Type - { - My_Type (My_Type const&); - }; - </pre><p> - Note the const keyword; the object being copied shouldn't change. - The template class <code class="code">auto_ptr</code> (called AP here) does not - meet this requirement. Creating a new AP by copying an existing - one transfers ownership of the pointed-to object, which means that - the AP being copied must change, which in turn means that the - copy ctors of AP do not take const objects. - </p><p> - The resulting rule is simple: <span class="emphasis"><em>Never ever use a - container of auto_ptr objects</em></span>. The standard says that - “<span class="quote">undefined</span>” behavior is the result, but it is - guaranteed to be messy. - </p><p> - To prevent you from doing this to yourself, the - <a class="ulink" href="../19_diagnostics/howto.html#3" target="_top">concept checks</a> built - in to this implementation will issue an error if you try to - compile code like this: - </p><pre class="programlisting"> - #include <vector> - #include <memory> - - void f() - { - std::vector< std::auto_ptr<int> > vec_ap_int; - } - </pre><p> -Should you try this with the checks enabled, you will see an error. - </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="memory.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="memory.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="shared_ptr.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 11. 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