1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>Parallel - Fork-Join -- EXPERIMENTAL</title> 6<link rel="stylesheet" href="../../../doc/src/boostbook.css" type="text/css"> 7<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 8<link rel="home" href="../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> 9<link rel="up" href="../thread.html" title="Chapter 39. Thread 4.8.0"> 10<link rel="prev" href="sds.html" title="Synchronized Data Structures"> 11<link rel="next" href="time.html" title="Time Requirements"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" width="100%"><tr> 15<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../boost.png"></td> 16<td align="center"><a href="../../../index.html">Home</a></td> 17<td align="center"><a href="../../../libs/libraries.htm">Libraries</a></td> 18<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 19<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 20<td align="center"><a href="../../../more/index.htm">More</a></td> 21</tr></table> 22<hr> 23<div class="spirit-nav"> 24<a accesskey="p" href="sds.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../thread.html"><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="time.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="section"> 27<div class="titlepage"><div><div><h2 class="title" style="clear: both"> 28<a name="thread.parallel"></a><a class="link" href="parallel.html" title="Parallel - Fork-Join -- EXPERIMENTAL">Parallel - Fork-Join -- EXPERIMENTAL</a> 29</h2></div></div></div> 30<div class="toc"><dl class="toc"> 31<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join">Fork-Join</a></span></dt> 32<dt><span class="section"><a href="parallel.html#thread.parallel.ref">Reference -- EXPERIMENTAL</a></span></dt> 33</dl></div> 34<div class="section"> 35<div class="titlepage"><div><div><h3 class="title"> 36<a name="thread.parallel.fork_join"></a><a class="link" href="parallel.html#thread.parallel.fork_join" title="Fork-Join">Fork-Join</a> 37</h3></div></div></div> 38<div class="toc"><dl class="toc"> 39<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join.introduction">Introduction</a></span></dt> 40<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join.tutorial">Tutorial</a></span></dt> 41<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join.examples">Examples</a></span></dt> 42<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join.rationale">Design Rationale</a></span></dt> 43</dl></div> 44<div class="warning"><table border="0" summary="Warning"> 45<tr> 46<td rowspan="2" align="center" valign="top" width="25"><img alt="[Warning]" src="../../../doc/src/images/warning.png"></td> 47<th align="left">Warning</th> 48</tr> 49<tr><td align="left" valign="top"><p> 50 These features are experimental and subject to change in future versions. 51 There are not too much tests yet, so it is possible that you can find out 52 some trivial bugs :( 53 </p></td></tr> 54</table></div> 55<div class="note"><table border="0" summary="Note"> 56<tr> 57<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../doc/src/images/note.png"></td> 58<th align="left">Note</th> 59</tr> 60<tr><td align="left" valign="top"><p> 61 These features are based on the <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4088.pdf" target="_top"><span class="bold"><strong>n4088 - Task Region R3</strong></span></a> C++1y proposal from 62 P. Halpern, A. Robison, A. Laksberg, H. Sutter, et al. The text that follows 63 has been adapted from this paper to show the differences. 64 </p></td></tr> 65</table></div> 66<p> 67 The major difference respect to the standard proposal is that we are able 68 to use a common executor for several task regions. 69 </p> 70<div class="note"><table border="0" summary="Note"> 71<tr> 72<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../doc/src/images/note.png"></td> 73<th align="left">Note</th> 74</tr> 75<tr><td align="left" valign="top"><p> 76 Up to now, Boost.Thread doesn't implement the parallel algorithms as defined 77 in <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4105.pdf" target="_top"><span class="bold"><strong>n4105 - Information technology – Programming languages, their 78 environments and system software interfaces – Technical Specification 79 for C++ Extensions for Parallelism</strong></span></a>. 80 </p></td></tr> 81</table></div> 82<div class="section"> 83<div class="titlepage"><div><div><h4 class="title"> 84<a name="thread.parallel.fork_join.introduction"></a><a class="link" href="parallel.html#thread.parallel.fork_join.introduction" title="Introduction">Introduction</a> 85</h4></div></div></div> 86<p> 87 This module introduces a C++11/c++14 library function template <code class="computeroutput"><span class="identifier">task_region</span></code> and a library class <code class="computeroutput"><span class="identifier">task_region_handle</span></code> with member functions 88 <code class="computeroutput"><span class="identifier">run</span></code> and <code class="computeroutput"><span class="identifier">wait</span></code> 89 that together enable developers to write expressive and portable fork-join 90 parallel code. 91 </p> 92<p> 93 The working draft for the Parallelism TS <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4105.pdf" target="_top"><span class="bold"><strong>N4105</strong></span></a> augments the STL algorithms with the 94 inclusion of parallel execution policies. Programmers use these as a basis 95 to write additional high-level algorithms that can be implemented in terms 96 of the provided parallel algorithms. However, the scope of n4105 does not 97 include lower-level mechanisms to express arbitrary fork-join parallelism 98 </p> 99<p> 100 The <code class="computeroutput"><span class="identifier">task_region</span></code>, <code class="computeroutput"><span class="identifier">run</span></code> and the <code class="computeroutput"><span class="identifier">wait</span></code> 101 functions provided by this library are based on the <code class="computeroutput"><span class="identifier">task_group</span></code> 102 concept that is a part of the common subset of the PPL and the TBB libraries. 103 </p> 104</div> 105<div class="section"> 106<div class="titlepage"><div><div><h4 class="title"> 107<a name="thread.parallel.fork_join.tutorial"></a><a class="link" href="parallel.html#thread.parallel.fork_join.tutorial" title="Tutorial">Tutorial</a> 108</h4></div></div></div> 109<p> 110 Consider an example of a parallel traversal of a tree, where a user-provided 111 function compute is applied to each node of the tree, returning the sum 112 of the results: 113 </p> 114<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Func</span><span class="special">></span> 115<span class="keyword">int</span> <span class="identifier">traverse</span><span class="special">(</span><span class="identifier">node</span> <span class="special">*</span><span class="identifier">n</span><span class="special">,</span> <span class="identifier">Func</span><span class="special">&&</span> <span class="identifier">compute</span><span class="special">)</span> 116<span class="special">{</span> 117 <span class="keyword">int</span> <span class="identifier">left</span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="identifier">right</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span> 118 <span class="identifier">task_region</span><span class="special">([&](</span><span class="identifier">task_region_handle</span><span class="special">&</span> <span class="identifier">tr</span><span class="special">)</span> <span class="special">{</span> 119 <span class="keyword">if</span> <span class="special">(</span><span class="identifier">n</span><span class="special">-></span><span class="identifier">left</span><span class="special">)</span> 120 <span class="identifier">tr</span><span class="special">.</span><span class="identifier">run</span><span class="special">([&]</span> <span class="special">{</span> <span class="identifier">left</span> <span class="special">=</span> <span class="identifier">traverse</span><span class="special">(</span><span class="identifier">n</span><span class="special">-></span><span class="identifier">left</span><span class="special">,</span> <span class="identifier">compute</span><span class="special">);</span> <span class="special">});</span> 121 <span class="keyword">if</span> <span class="special">(</span><span class="identifier">n</span><span class="special">-></span><span class="identifier">right</span><span class="special">)</span> 122 <span class="identifier">tr</span><span class="special">.</span><span class="identifier">run</span><span class="special">([&]</span> <span class="special">{</span> <span class="identifier">right</span> <span class="special">=</span> <span class="identifier">traverse</span><span class="special">(</span><span class="identifier">n</span><span class="special">-></span><span class="identifier">right</span><span class="special">,</span> <span class="identifier">compute</span><span class="special">);</span> <span class="special">});</span> 123 <span class="special">});</span> 124 <span class="keyword">return</span> <span class="identifier">compute</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span> <span class="special">+</span> <span class="identifier">left</span> <span class="special">+</span> <span class="identifier">right</span><span class="special">;</span> 125<span class="special">}</span> 126</pre> 127<p> 128 The example above demonstrates the use of two of the functions proposed 129 in this paper, <code class="computeroutput"><span class="identifier">task_region</span></code> 130 and <code class="computeroutput"><span class="identifier">task_region_handle</span><span class="special">::</span><span class="identifier">run</span></code>. 131 The <code class="computeroutput"><span class="identifier">task_region</span></code> function 132 delineates a region in a program code potentially containing invocations 133 of tasks spawned by the <code class="computeroutput"><span class="identifier">run</span></code> 134 member function of the <code class="computeroutput"><span class="identifier">task_region_handle</span></code> 135 class. 136 </p> 137<p> 138 The run function spawns a task, a unit of work that is allowed to execute 139 in parallel with respect to the caller. Any parallel tasks spawned by 140 <code class="computeroutput"><span class="identifier">run</span></code> within the <code class="computeroutput"><span class="identifier">task_region</span></code> are joined back to a single 141 thread of execution at the end of the <code class="computeroutput"><span class="identifier">task_region</span></code>. 142 </p> 143<p> 144 <code class="computeroutput"><span class="identifier">run</span></code> takes a user-provided 145 function object <code class="computeroutput"><span class="identifier">f</span></code> and starts 146 it asynchronously - i.e. it may return before the execution of <code class="computeroutput"><span class="identifier">f</span></code> completes. The implementation's scheduler 147 may choose to run <code class="computeroutput"><span class="identifier">f</span></code> immediately 148 or delay running <code class="computeroutput"><span class="identifier">f</span></code> until 149 compute resources become available. 150 </p> 151<p> 152 A <code class="computeroutput"><span class="identifier">task_region_handle</span></code> can 153 be constructed only by <code class="computeroutput"><span class="identifier">task_region</span></code> 154 because it has no public constructors. Thus, <code class="computeroutput"><span class="identifier">run</span></code> 155 can be invoked (directly or indirectly) only from a user-provided function 156 passed to <code class="computeroutput"><span class="identifier">task_region</span></code>: 157 </p> 158<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">g</span><span class="special">();</span> 159<span class="keyword">void</span> <span class="identifier">f</span><span class="special">(</span><span class="identifier">task_region_handle</span><span class="special">&</span> <span class="identifier">tr</span><span class="special">)</span> 160<span class="special">{</span> 161 <span class="identifier">tr</span><span class="special">.</span><span class="identifier">run</span><span class="special">(</span><span class="identifier">g</span><span class="special">);</span> <span class="comment">// OK, invoked from within task_region in h</span> 162<span class="special">}</span> 163<span class="keyword">void</span> <span class="identifier">h</span><span class="special">()</span> 164<span class="special">{</span> 165 <span class="identifier">task_region</span><span class="special">(</span><span class="identifier">f</span><span class="special">);</span> 166<span class="special">}</span> 167 168<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> 169<span class="special">{</span> 170 <span class="identifier">task_region_handle</span> <span class="identifier">tr</span><span class="special">;</span> <span class="comment">// Error: no public constructor</span> 171 <span class="identifier">tr</span><span class="special">.</span><span class="identifier">run</span><span class="special">(</span><span class="identifier">g</span><span class="special">);</span> <span class="comment">// No way to call run outside of a task_region</span> 172 <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> 173<span class="special">}</span> 174</pre> 175</div> 176<div class="section"> 177<div class="titlepage"><div><div><h4 class="title"> 178<a name="thread.parallel.fork_join.examples"></a><a class="link" href="parallel.html#thread.parallel.fork_join.examples" title="Examples">Examples</a> 179</h4></div></div></div> 180<div class="toc"><dl class="toc"> 181<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join.examples.fib">Parallel 182 Fibonacci</a></span></dt> 183<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join.examples.fibex">Parallel 184 Fibonacci - Specific executor</a></span></dt> 185<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join.examples.quick_sort">Parallel 186 Accumulate</a></span></dt> 187<dt><span class="section"><a href="parallel.html#thread.parallel.fork_join.examples.quick_sort0">Parallel 188 Quick Sort</a></span></dt> 189</dl></div> 190<div class="section"> 191<div class="titlepage"><div><div><h5 class="title"> 192<a name="thread.parallel.fork_join.examples.fib"></a><a class="link" href="parallel.html#thread.parallel.fork_join.examples.fib" title="Parallel Fibonacci">Parallel 193 Fibonacci</a> 194</h5></div></div></div> 195<p> 196 This is surely the worst implementation of the Fibonacci function. Anyway, 197 here it is, as it is simple and shows the fork-join structure clearly. 198 <code class="computeroutput"><span class="identifier">Fibonacci</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span> <span class="special">=</span> <span class="identifier">Fibonacci</span><span class="special">(</span><span class="identifier">n</span><span class="special">-</span><span class="number">1</span><span class="special">)</span> 199 <span class="special">+</span> <span class="identifier">Fibonacci</span><span class="special">(</span><span class="identifier">n</span><span class="special">-</span><span class="number">2</span><span class="special">)</span></code>, 200 so the task decomposition is trivial. 201 </p> 202<pre class="programlisting"><span class="keyword">int</span> <span class="identifier">fib_task_region</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">n</span><span class="special">)</span> 203<span class="special">{</span> 204 <span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">experimental</span><span class="special">::</span><span class="identifier">parallel</span><span class="special">::</span><span class="identifier">task_region</span><span class="special">;</span> 205 <span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">experimental</span><span class="special">::</span><span class="identifier">parallel</span><span class="special">::</span><span class="identifier">task_region_handle</span><span class="special">;</span> 206 207 <span class="keyword">if</span> <span class="special">(</span><span class="identifier">n</span> <span class="special">==</span> <span class="number">0</span><span class="special">)</span> <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> 208 <span class="keyword">if</span> <span class="special">(</span><span class="identifier">n</span> <span class="special">==</span> <span class="number">1</span><span class="special">)</span> <span class="keyword">return</span> <span class="number">1</span><span class="special">;</span> 209 210 <span class="keyword">int</span> <span class="identifier">n1</span><span class="special">;</span> 211 <span class="keyword">int</span> <span class="identifier">n2</span><span class="special">;</span> 212 213 <span class="identifier">task_region</span><span class="special">([&](</span><span class="identifier">task_region_handle</span><span class="special">&</span> <span class="identifier">trh</span><span class="special">)</span> 214 <span class="special">{</span> 215 <span class="identifier">trh</span><span class="special">.</span><span class="identifier">run</span><span class="special">([&]</span> 216 <span class="special">{</span> 217 <span class="identifier">n1</span> <span class="special">=</span> <span class="identifier">fib_task_region</span><span class="special">(</span><span class="identifier">n</span> <span class="special">-</span> <span class="number">1</span><span class="special">);</span> 218 <span class="special">});</span> 219 220 <span class="identifier">n2</span> <span class="special">=</span> <span class="identifier">fib_task_region</span><span class="special">(</span><span class="identifier">n</span> <span class="special">-</span> <span class="number">2</span><span class="special">);</span> 221 <span class="special">});</span> 222 223 <span class="keyword">return</span> <span class="identifier">n1</span> <span class="special">+</span> <span class="identifier">n2</span><span class="special">;</span> 224<span class="special">}</span> 225 226<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> 227<span class="special">{</span> 228 <span class="keyword">for</span> <span class="special">(</span><span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span> <span class="identifier">i</span><span class="special"><</span><span class="number">10</span><span class="special">;</span> <span class="special">++</span><span class="identifier">i</span><span class="special">)</span> <span class="special">{</span> 229 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">fib_task_region</span><span class="special">(</span><span class="identifier">i</span><span class="special">)</span> <span class="special"><<</span> <span class="string">" "</span><span class="special">;</span> 230 <span class="special">}</span> 231 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> 232<span class="special">}</span> 233</pre> 234</div> 235<div class="section"> 236<div class="titlepage"><div><div><h5 class="title"> 237<a name="thread.parallel.fork_join.examples.fibex"></a><a class="link" href="parallel.html#thread.parallel.fork_join.examples.fibex" title="Parallel Fibonacci - Specific executor">Parallel 238 Fibonacci - Specific executor</a> 239</h5></div></div></div> 240<p> 241 The previous example make use of an implementation defined way to spawn 242 the tasks. Often the user wants to master how the task must be spawned. 243 There is an overload of <code class="computeroutput"><span class="identifier">task_region</span></code> 244 that accept an additional <code class="computeroutput"><span class="identifier">Executor</span></code> 245 parameter and a function that takes as parameter a <code class="computeroutput"><span class="identifier">task_region_handle_gen</span><span class="special"><</span><span class="identifier">Executor</span><span class="special">></span></code>. <code class="computeroutput"><span class="identifier">task_region_handle_gen</span><span class="special"><</span><span class="identifier">Executor</span><span class="special">></span></code> run uses this executor to spawn the 246 tasks. 247 </p> 248<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">Ex</span><span class="special">></span> 249<span class="keyword">int</span> <span class="identifier">fib_task_region_gen</span><span class="special">(</span> <span class="identifier">Ex</span><span class="special">&</span> <span class="identifier">ex</span><span class="special">,</span> <span class="keyword">int</span> <span class="identifier">n</span><span class="special">)</span> 250<span class="special">{</span> 251 <span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">experimental</span><span class="special">::</span><span class="identifier">parallel</span><span class="special">::</span><span class="identifier">task_region</span><span class="special">;</span> 252 <span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">experimental</span><span class="special">::</span><span class="identifier">parallel</span><span class="special">::</span><span class="identifier">task_region_handle_gen</span><span class="special">;</span> 253 254 <span class="keyword">if</span> <span class="special">(</span><span class="identifier">n</span> <span class="special">==</span> <span class="number">0</span><span class="special">)</span> <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> 255 <span class="keyword">if</span> <span class="special">(</span><span class="identifier">n</span> <span class="special">==</span> <span class="number">1</span><span class="special">)</span> <span class="keyword">return</span> <span class="number">1</span><span class="special">;</span> 256 257 <span class="keyword">int</span> <span class="identifier">n1</span><span class="special">;</span> 258 <span class="keyword">int</span> <span class="identifier">n2</span><span class="special">;</span> 259 260 <span class="identifier">task_region</span><span class="special">(</span><span class="identifier">ex</span><span class="special">,</span> <span class="special">[&](</span><span class="identifier">task_region_handle_gen</span><span class="special"><</span><span class="identifier">Ex</span><span class="special">>&</span> <span class="identifier">trh</span><span class="special">)</span> <span class="comment">// (2)</span> 261 <span class="special">{</span> 262 <span class="identifier">trh</span><span class="special">.</span><span class="identifier">run</span><span class="special">([&]</span> 263 <span class="special">{</span> 264 <span class="identifier">n1</span> <span class="special">=</span> <span class="identifier">fib_task_region</span><span class="special">(</span><span class="identifier">n</span> <span class="special">-</span> <span class="number">1</span><span class="special">);</span> 265 <span class="special">});</span> 266 267 <span class="identifier">n2</span> <span class="special">=</span> <span class="identifier">fib_task_region</span><span class="special">(</span><span class="identifier">n</span> <span class="special">-</span> <span class="number">2</span><span class="special">);</span> 268 <span class="special">});</span> 269 270 <span class="keyword">return</span> <span class="identifier">n1</span> <span class="special">+</span> <span class="identifier">n2</span><span class="special">;</span> 271<span class="special">}</span> 272 273<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> 274<span class="special">{</span> 275 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">basic_thread_pool</span> <span class="identifier">tp</span><span class="special">;</span> <span class="comment">// (1)</span> 276 <span class="keyword">for</span> <span class="special">(</span><span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span> <span class="identifier">i</span><span class="special"><</span><span class="number">10</span><span class="special">;</span> <span class="special">++</span><span class="identifier">i</span><span class="special">)</span> <span class="special">{</span> 277 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">fib_task_region_gen</span><span class="special">(</span><span class="identifier">tp</span><span class="special">,</span><span class="identifier">i</span><span class="special">)</span> <span class="special"><<</span> <span class="string">" "</span><span class="special">;</span> 278 <span class="special">}</span> 279 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> 280 <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> 281<span class="special">}</span> 282</pre> 283<p> 284 The specific executor is declared in line (1) and it is used in line 285 (2). 286 </p> 287</div> 288<div class="section"><div class="titlepage"><div><div><h5 class="title"> 289<a name="thread.parallel.fork_join.examples.quick_sort"></a><a class="link" href="parallel.html#thread.parallel.fork_join.examples.quick_sort" title="Parallel Accumulate">Parallel 290 Accumulate</a> 291</h5></div></div></div></div> 292<div class="section"><div class="titlepage"><div><div><h5 class="title"> 293<a name="thread.parallel.fork_join.examples.quick_sort0"></a><a class="link" href="parallel.html#thread.parallel.fork_join.examples.quick_sort0" title="Parallel Quick Sort">Parallel 294 Quick Sort</a> 295</h5></div></div></div></div> 296</div> 297<div class="section"><div class="titlepage"><div><div><h4 class="title"> 298<a name="thread.parallel.fork_join.rationale"></a><a class="link" href="parallel.html#thread.parallel.fork_join.rationale" title="Design Rationale">Design Rationale</a> 299</h4></div></div></div></div> 300</div> 301<div class="section"> 302<div class="titlepage"><div><div><h3 class="title"> 303<a name="thread.parallel.ref"></a><a class="link" href="parallel.html#thread.parallel.ref" title="Reference -- EXPERIMENTAL">Reference -- EXPERIMENTAL</a> 304</h3></div></div></div> 305<div class="toc"><dl class="toc"> 306<dt><span class="section"><a href="parallel.html#thread.parallel.ref.v1">Parallel V1</a></span></dt> 307<dt><span class="section"><a href="parallel.html#thread.parallel.ref.v2">Parallel V2</a></span></dt> 308</dl></div> 309<div class="section"> 310<div class="titlepage"><div><div><h4 class="title"> 311<a name="thread.parallel.ref.v1"></a><a class="link" href="parallel.html#thread.parallel.ref.v1" title="Parallel V1">Parallel V1</a> 312</h4></div></div></div> 313<div class="toc"><dl class="toc"><dt><span class="section"><a href="parallel.html#thread.parallel.ref.v1.exception_list">Header <code class="computeroutput"><span class="special"><</span><span class="identifier">experimental</span><span class="special">/</span><span class="identifier">exception_list</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code></a></span></dt></dl></div> 314<div class="section"> 315<div class="titlepage"><div><div><h5 class="title"> 316<a name="thread.parallel.ref.v1.exception_list"></a><a class="link" href="parallel.html#thread.parallel.ref.v1.exception_list" title="Header <experimental/exception_list.hpp>">Header <code class="computeroutput"><span class="special"><</span><span class="identifier">experimental</span><span class="special">/</span><span class="identifier">exception_list</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code></a> 317</h5></div></div></div> 318<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 319<span class="special">{</span> 320<span class="keyword">namespace</span> <span class="identifier">experimental</span> 321<span class="special">{</span> 322<span class="keyword">namespace</span> <span class="identifier">parallel</span> 323<span class="special">{</span> 324<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v1</span> 325<span class="special">{</span> 326 327 <span class="keyword">class</span> <span class="identifier">exception_list</span><span class="special">;</span> 328 329<span class="special">}</span> <span class="comment">// v1</span> 330<span class="special">}</span> <span class="comment">// parallel</span> 331<span class="special">}</span> <span class="comment">// experimental</span> 332<span class="special">}</span> <span class="comment">// boost</span> 333</pre> 334<div class="section"> 335<div class="titlepage"><div><div><h6 class="title"> 336<a name="thread.parallel.ref.v1.exception_list.exception_list"></a><a class="link" href="parallel.html#thread.parallel.ref.v1.exception_list.exception_list" title="Class exception_list">Class 337 <code class="computeroutput"><span class="identifier">exception_list</span></code></a> 338</h6></div></div></div> 339<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 340<span class="special">{</span> 341<span class="keyword">namespace</span> <span class="identifier">experimental</span> 342<span class="special">{</span> 343<span class="keyword">namespace</span> <span class="identifier">parallel</span> 344<span class="special">{</span> 345<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v1</span> 346<span class="special">{</span> 347 348 <span class="keyword">class</span> <span class="identifier">exception_list</span><span class="special">:</span> <span class="keyword">public</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">exception</span> 349 <span class="special">{</span> 350 <span class="keyword">public</span><span class="special">:</span> 351 <span class="keyword">typedef</span> <span class="char">'implementation defined'</span> <span class="identifier">const_iterator</span><span class="special">;</span> 352 353 <span class="special">~</span><span class="identifier">exception_list</span><span class="special">()</span> <span class="keyword">noexcept</span> <span class="special">{}</span> 354 355 <span class="keyword">void</span> <span class="identifier">add</span><span class="special">(</span><span class="identifier">exception_ptr</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">e</span><span class="special">);</span> 356 <span class="identifier">size_t</span> <span class="identifier">size</span><span class="special">()</span> <span class="keyword">const</span> <span class="keyword">noexcept</span><span class="special">;</span> 357 <span class="identifier">const_iterator</span> <span class="identifier">begin</span><span class="special">()</span> <span class="keyword">const</span> <span class="keyword">noexcept</span><span class="special">;</span> 358 <span class="identifier">const_iterator</span> <span class="identifier">end</span><span class="special">()</span> <span class="keyword">const</span> <span class="keyword">noexcept</span><span class="special">;</span> 359 <span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">what</span><span class="special">()</span> <span class="keyword">const</span> <span class="keyword">noexcept</span><span class="special">;</span> 360 361 <span class="special">};</span> 362 363<span class="special">}</span> <span class="comment">// v1</span> 364<span class="special">}</span> <span class="comment">// parallel</span> 365<span class="special">}</span> <span class="comment">// experimental</span> 366<span class="special">}</span> <span class="comment">// boost</span> 367</pre> 368</div> 369</div> 370</div> 371<div class="section"> 372<div class="titlepage"><div><div><h4 class="title"> 373<a name="thread.parallel.ref.v2"></a><a class="link" href="parallel.html#thread.parallel.ref.v2" title="Parallel V2">Parallel V2</a> 374</h4></div></div></div> 375<div class="toc"><dl class="toc"> 376<dt><span class="section"><a href="parallel.html#thread.parallel.ref.v2.concepts">Concepts</a></span></dt> 377<dt><span class="section"><a href="parallel.html#thread.parallel.ref.v2.task_region">Header <code class="computeroutput"><span class="special"><</span><span class="identifier">experimental</span><span class="special">/</span><span class="identifier">task_region</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code></a></span></dt> 378</dl></div> 379<div class="section"> 380<div class="titlepage"><div><div><h5 class="title"> 381<a name="thread.parallel.ref.v2.concepts"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.concepts" title="Concepts">Concepts</a> 382</h5></div></div></div> 383<div class="section"><div class="titlepage"><div><div><h6 class="title"> 384<a name="thread.parallel.ref.v2.concepts.regionCallable"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.concepts.regionCallable" title="Concept Region_Callable">Concept 385 <code class="computeroutput"><span class="identifier">Region_Callable</span></code></a> 386</h6></div></div></div></div> 387<div class="section"><div class="titlepage"><div><div><h6 class="title"> 388<a name="thread.parallel.ref.v2.concepts.taskCallable"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.concepts.taskCallable" title="Concept Task_Callable">Concept 389 <code class="computeroutput"><span class="identifier">Task_Callable</span></code></a> 390</h6></div></div></div></div> 391</div> 392<div class="section"> 393<div class="titlepage"><div><div><h5 class="title"> 394<a name="thread.parallel.ref.v2.task_region"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.task_region" title="Header <experimental/task_region.hpp>">Header <code class="computeroutput"><span class="special"><</span><span class="identifier">experimental</span><span class="special">/</span><span class="identifier">task_region</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code></a> 395</h5></div></div></div> 396<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 397<span class="special">{</span> 398<span class="keyword">namespace</span> <span class="identifier">experimental</span> 399<span class="special">{</span> 400<span class="keyword">namespace</span> <span class="identifier">parallel</span> 401<span class="special">{</span> 402<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v2</span> 403<span class="special">{</span> 404 405 <span class="keyword">class</span> <span class="identifier">task_canceled_exception</span><span class="special">;</span> 406 407 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">Executor</span><span class="special">></span> 408 <span class="keyword">class</span> <span class="identifier">task_region_handle_gen</span><span class="special">;</span> 409 410 <span class="keyword">using</span> <span class="identifier">default_executor</span> <span class="special">=</span> <span class="char">'implementation defined'</span><span class="special">;</span> 411 412 <span class="keyword">class</span> <span class="identifier">task_region_handle</span><span class="special">;</span> 413 414 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Executor</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 415 <span class="keyword">void</span> <span class="identifier">task_region_final</span><span class="special">(</span><span class="identifier">Executor</span><span class="special">&</span> <span class="identifier">ex</span><span class="special">,</span> <span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 416 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 417 <span class="keyword">void</span> <span class="identifier">task_region_final</span><span class="special">(</span><span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 418 419 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Executor</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 420 <span class="keyword">void</span> <span class="identifier">task_region</span><span class="special">(</span><span class="identifier">Executor</span><span class="special">&</span> <span class="identifier">ex</span><span class="special">,</span> <span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 421 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 422 <span class="keyword">void</span> <span class="identifier">task_region</span><span class="special">(</span><span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 423 424<span class="special">}</span> <span class="comment">// v2</span> 425<span class="special">}</span> <span class="comment">// parallel</span> 426<span class="special">}</span> <span class="comment">// experimental</span> 427<span class="special">}</span> <span class="comment">// boost</span> 428</pre> 429<div class="section"> 430<div class="titlepage"><div><div><h6 class="title"> 431<a name="thread.parallel.ref.v2.task_region.task_canceled_exception"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.task_region.task_canceled_exception" title="Class task_canceled_exception">Class 432 <code class="computeroutput"><span class="identifier">task_canceled_exception</span> </code></a> 433</h6></div></div></div> 434<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 435<span class="special">{</span> 436<span class="keyword">namespace</span> <span class="identifier">experimental</span> 437<span class="special">{</span> 438<span class="keyword">namespace</span> <span class="identifier">parallel</span> 439<span class="special">{</span> 440<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v2</span> 441<span class="special">{</span> 442 443 <span class="keyword">class</span> <span class="identifier">task_canceled_exception</span><span class="special">:</span> <span class="keyword">public</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">exception</span> 444 <span class="special">{</span> 445 <span class="keyword">public</span><span class="special">:</span> 446 <span class="identifier">task_canceled_exception</span><span class="special">()</span> <span class="keyword">noexcept</span><span class="special">;</span> 447 <span class="identifier">task_canceled_exception</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">task_canceled_exception</span><span class="special">&)</span> <span class="keyword">noexcept</span><span class="special">;</span> 448 <span class="identifier">task_canceled_exception</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">task_canceled_exception</span><span class="special">&)</span> <span class="keyword">noexcept</span><span class="special">;</span> 449 <span class="keyword">virtual</span> <span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">what</span><span class="special">()</span> <span class="keyword">const</span> <span class="keyword">noexcept</span><span class="special">;</span> 450 <span class="special">};</span> 451 452<span class="special">}</span> <span class="comment">// v2</span> 453<span class="special">}</span> <span class="comment">// parallel</span> 454<span class="special">}</span> <span class="comment">// experimental</span> 455<span class="special">}</span> <span class="comment">// boost</span> 456</pre> 457</div> 458<div class="section"> 459<div class="titlepage"><div><div><h6 class="title"> 460<a name="thread.parallel.ref.v2.task_region.task_region_handle_gen"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.task_region.task_region_handle_gen" title="Template Class task_region_handle_gen<>">Template 461 Class <code class="computeroutput"><span class="identifier">task_region_handle_gen</span><span class="special"><></span></code></a> 462</h6></div></div></div> 463<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 464<span class="special">{</span> 465<span class="keyword">namespace</span> <span class="identifier">experimental</span> 466<span class="special">{</span> 467<span class="keyword">namespace</span> <span class="identifier">parallel</span> 468<span class="special">{</span> 469<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v2</span> 470<span class="special">{</span> 471 472 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">Executor</span><span class="special">></span> 473 <span class="keyword">class</span> <span class="identifier">task_region_handle_gen</span> 474 <span class="special">{</span> 475 <span class="keyword">protected</span><span class="special">:</span> 476 <span class="identifier">task_region_handle_gen</span><span class="special">(</span><span class="identifier">Executor</span><span class="special">&</span> <span class="identifier">ex</span><span class="special">);</span> 477 478 <span class="special">~</span><span class="identifier">task_region_handle_gen</span><span class="special">();</span> 479 480 <span class="keyword">public</span><span class="special">:</span> 481 <span class="identifier">task_region_handle_gen</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">task_region_handle_gen</span><span class="special">&)</span> <span class="special">=</span> <span class="keyword">delete</span><span class="special">;</span> 482 <span class="identifier">task_region_handle_gen</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">task_region_handle_gen</span><span class="special">&)</span> <span class="special">=</span> <span class="keyword">delete</span><span class="special">;</span> 483 <span class="identifier">task_region_handle_gen</span><span class="special">*</span> <span class="keyword">operator</span><span class="special">&()</span> <span class="keyword">const</span> <span class="special">=</span> <span class="keyword">delete</span><span class="special">;</span> 484 485 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 486 <span class="keyword">void</span> <span class="identifier">run</span><span class="special">(</span><span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 487 488 <span class="keyword">void</span> <span class="identifier">wait</span><span class="special">();</span> 489 <span class="special">};</span> 490 491<span class="special">}</span> <span class="comment">// v2</span> 492<span class="special">}</span> <span class="comment">// parallel</span> 493<span class="special">}</span> <span class="comment">// experimental</span> 494<span class="special">}</span> <span class="comment">// boost</span> 495</pre> 496</div> 497<div class="section"> 498<div class="titlepage"><div><div><h6 class="title"> 499<a name="thread.parallel.ref.v2.task_region.default_executor"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.task_region.default_executor" title="Class default_executor">Class 500 <code class="computeroutput"><span class="identifier">default_executor</span> </code></a> 501</h6></div></div></div> 502<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 503<span class="special">{</span> 504<span class="keyword">namespace</span> <span class="identifier">experimental</span> 505<span class="special">{</span> 506<span class="keyword">namespace</span> <span class="identifier">parallel</span> 507<span class="special">{</span> 508<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v2</span> 509<span class="special">{</span> 510 511 <span class="keyword">using</span> <span class="identifier">default_executor</span> <span class="special">=</span> <span class="char">'implementation defined'</span><span class="special">;</span> 512 513<span class="special">}</span> <span class="comment">// v2</span> 514<span class="special">}</span> <span class="comment">// parallel</span> 515<span class="special">}</span> <span class="comment">// experimental</span> 516<span class="special">}</span> <span class="comment">// boost</span> 517</pre> 518</div> 519<div class="section"> 520<div class="titlepage"><div><div><h6 class="title"> 521<a name="thread.parallel.ref.v2.task_region.task_region_handle"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.task_region.task_region_handle" title="Class task_region_handle">Class 522 <code class="computeroutput"><span class="identifier">task_region_handle</span> </code></a> 523</h6></div></div></div> 524<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 525<span class="special">{</span> 526<span class="keyword">namespace</span> <span class="identifier">experimental</span> 527<span class="special">{</span> 528<span class="keyword">namespace</span> <span class="identifier">parallel</span> 529<span class="special">{</span> 530<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v2</span> 531<span class="special">{</span> 532 533 <span class="keyword">class</span> <span class="identifier">task_region_handle</span> <span class="special">:</span> 534 <span class="keyword">public</span> <span class="identifier">task_region_handle_gen</span><span class="special"><</span><span class="identifier">default_executor</span><span class="special">></span> 535 <span class="special">{</span> 536 <span class="keyword">protected</span><span class="special">:</span> 537 <span class="identifier">task_region_handle</span><span class="special">();</span> 538 <span class="identifier">task_region_handle</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">task_region_handle</span><span class="special">&)</span> <span class="special">=</span> <span class="keyword">delete</span><span class="special">;</span> 539 <span class="identifier">task_region_handle</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">task_region_handle</span><span class="special">&)</span> <span class="special">=</span> <span class="keyword">delete</span><span class="special">;</span> 540 <span class="identifier">task_region_handle</span><span class="special">*</span> <span class="keyword">operator</span><span class="special">&()</span> <span class="keyword">const</span> <span class="special">=</span> <span class="keyword">delete</span><span class="special">;</span> 541 542 <span class="special">};</span> 543 544<span class="special">}</span> <span class="comment">// v2</span> 545<span class="special">}</span> <span class="comment">// parallel</span> 546<span class="special">}</span> <span class="comment">// experimental</span> 547<span class="special">}</span> <span class="comment">// boost</span> 548</pre> 549</div> 550<div class="section"> 551<div class="titlepage"><div><div><h6 class="title"> 552<a name="thread.parallel.ref.v2.task_region.task_region_final"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.task_region.task_region_final" title="Template Function task_region_final">Template 553 Function <code class="computeroutput"><span class="identifier">task_region_final</span> 554 </code></a> 555</h6></div></div></div> 556<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 557<span class="special">{</span> 558<span class="keyword">namespace</span> <span class="identifier">experimental</span> 559<span class="special">{</span> 560<span class="keyword">namespace</span> <span class="identifier">parallel</span> 561<span class="special">{</span> 562<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v2</span> 563<span class="special">{</span> 564 565 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Executor</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 566 <span class="keyword">void</span> <span class="identifier">task_region_final</span><span class="special">(</span><span class="identifier">Executor</span><span class="special">&</span> <span class="identifier">ex</span><span class="special">,</span> <span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 567 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 568 <span class="keyword">void</span> <span class="identifier">task_region_final</span><span class="special">(</span><span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 569 570<span class="special">}</span> <span class="comment">// v2</span> 571<span class="special">}</span> <span class="comment">// parallel</span> 572<span class="special">}</span> <span class="comment">// experimental</span> 573<span class="special">}</span> <span class="comment">// boost</span> 574</pre> 575</div> 576<div class="section"> 577<div class="titlepage"><div><div><h6 class="title"> 578<a name="thread.parallel.ref.v2.task_region.task_region"></a><a class="link" href="parallel.html#thread.parallel.ref.v2.task_region.task_region" title="Template Function task_region">Template 579 Function <code class="computeroutput"><span class="identifier">task_region</span> </code></a> 580</h6></div></div></div> 581<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> 582<span class="special">{</span> 583<span class="keyword">namespace</span> <span class="identifier">experimental</span> 584<span class="special">{</span> 585<span class="keyword">namespace</span> <span class="identifier">parallel</span> 586<span class="special">{</span> 587<span class="keyword">inline</span> <span class="keyword">namespace</span> <span class="identifier">v2</span> 588<span class="special">{</span> 589 590 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Executor</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 591 <span class="keyword">void</span> <span class="identifier">task_region</span><span class="special">(</span><span class="identifier">Executor</span><span class="special">&</span> <span class="identifier">ex</span><span class="special">,</span> <span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 592 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">F</span><span class="special">></span> 593 <span class="keyword">void</span> <span class="identifier">task_region</span><span class="special">(</span><span class="identifier">F</span><span class="special">&&</span> <span class="identifier">f</span><span class="special">);</span> 594 595<span class="special">}</span> <span class="comment">// v2</span> 596<span class="special">}</span> <span class="comment">// parallel</span> 597<span class="special">}</span> <span class="comment">// experimental</span> 598<span class="special">}</span> <span class="comment">// boost</span> 599</pre> 600</div> 601</div> 602</div> 603</div> 604</div> 605<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 606<td align="left"></td> 607<td align="right"><div class="copyright-footer">Copyright © 2007 -11 Anthony Williams<br>Copyright © 2011 -17 Vicente J. Botet Escriba<p> 608 Distributed under the Boost Software License, Version 1.0. (See accompanying 609 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>) 610 </p> 611</div></td> 612</tr></table> 613<hr> 614<div class="spirit-nav"> 615<a accesskey="p" href="sds.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../thread.html"><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="time.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> 616</div> 617</body> 618</html> 619
