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diff --git a/doc/html/boost_asio/reference/high_resolution_timer.html b/doc/html/boost_asio/reference/high_resolution_timer.html new file mode 100644 index 0000000000..a3957d28f9 --- /dev/null +++ b/doc/html/boost_asio/reference/high_resolution_timer.html @@ -0,0 +1,508 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>high_resolution_timer</title> +<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> +<link rel="home" href="../../boost_asio.html" title="Boost.Asio"> +<link rel="up" href="../reference.html" title="Reference"> +<link rel="prev" href="has_service.html" title="has_service"> +<link rel="next" href="invalid_service_owner.html" title="invalid_service_owner"> +</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++ 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class="title"> +<a name="boost_asio.reference.high_resolution_timer"></a><a class="link" href="high_resolution_timer.html" title="high_resolution_timer">high_resolution_timer</a> +</h3></div></div></div> +<p> + <a class="indexterm" name="idp144362816"></a> +Typedef for a timer based on the high resolution clock. + </p> +<pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">basic_waitable_timer</span><span class="special"><</span> <span class="identifier">chrono</span><span class="special">::</span><span class="identifier">high_resolution_clock</span> <span class="special">></span> <span class="identifier">high_resolution_timer</span><span class="special">;</span> +</pre> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h0"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.types"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.types">Types</a> + </h5> +<div class="informaltable"><table class="table"> +<colgroup> +<col> +<col> +</colgroup> +<thead><tr> +<th> + <p> + Name + </p> + </th> +<th> + <p> + Description + </p> + </th> +</tr></thead> +<tbody> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/clock_type.html" title="basic_waitable_timer::clock_type"><span class="bold"><strong>clock_type</strong></span></a> + </p> + </td> +<td> + <p> + The clock type. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/duration.html" title="basic_waitable_timer::duration"><span class="bold"><strong>duration</strong></span></a> + </p> + </td> +<td> + <p> + The duration type of the clock. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/implementation_type.html" title="basic_waitable_timer::implementation_type"><span class="bold"><strong>implementation_type</strong></span></a> + </p> + </td> +<td> + <p> + The underlying implementation type of I/O object. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/service_type.html" title="basic_waitable_timer::service_type"><span class="bold"><strong>service_type</strong></span></a> + </p> + </td> +<td> + <p> + The type of the service that will be used to provide I/O operations. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/time_point.html" title="basic_waitable_timer::time_point"><span class="bold"><strong>time_point</strong></span></a> + </p> + </td> +<td> + <p> + The time point type of the clock. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/traits_type.html" title="basic_waitable_timer::traits_type"><span class="bold"><strong>traits_type</strong></span></a> + </p> + </td> +<td> + <p> + The wait traits type. + </p> + </td> +</tr> +</tbody> +</table></div> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h1"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.member_functions"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.member_functions">Member + Functions</a> + </h5> +<div class="informaltable"><table class="table"> +<colgroup> +<col> +<col> +</colgroup> +<thead><tr> +<th> + <p> + Name + </p> + </th> +<th> + <p> + Description + </p> + </th> +</tr></thead> +<tbody> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/async_wait.html" title="basic_waitable_timer::async_wait"><span class="bold"><strong>async_wait</strong></span></a> + </p> + </td> +<td> + <p> + Start an asynchronous wait on the timer. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/basic_waitable_timer.html" title="basic_waitable_timer::basic_waitable_timer"><span class="bold"><strong>basic_waitable_timer</strong></span></a> + </p> + </td> +<td> + <p> + Constructor. + </p> + <p> + Constructor to set a particular expiry time as an absolute time. + </p> + <p> + Constructor to set a particular expiry time relative to now. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/cancel.html" title="basic_waitable_timer::cancel"><span class="bold"><strong>cancel</strong></span></a> + </p> + </td> +<td> + <p> + Cancel any asynchronous operations that are waiting on the timer. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/cancel_one.html" title="basic_waitable_timer::cancel_one"><span class="bold"><strong>cancel_one</strong></span></a> + </p> + </td> +<td> + <p> + Cancels one asynchronous operation that is waiting on the timer. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/expires_at.html" title="basic_waitable_timer::expires_at"><span class="bold"><strong>expires_at</strong></span></a> + </p> + </td> +<td> + <p> + Get the timer's expiry time as an absolute time. + </p> + <p> + Set the timer's expiry time as an absolute time. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/expires_from_now.html" title="basic_waitable_timer::expires_from_now"><span class="bold"><strong>expires_from_now</strong></span></a> + </p> + </td> +<td> + <p> + Get the timer's expiry time relative to now. + </p> + <p> + Set the timer's expiry time relative to now. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/get_io_service.html" title="basic_waitable_timer::get_io_service"><span class="bold"><strong>get_io_service</strong></span></a> + </p> + </td> +<td> + <p> + Get the io_service associated with the object. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/wait.html" title="basic_waitable_timer::wait"><span class="bold"><strong>wait</strong></span></a> + </p> + </td> +<td> + <p> + Perform a blocking wait on the timer. + </p> + </td> +</tr> +</tbody> +</table></div> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h2"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.protected_member_functions"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.protected_member_functions">Protected + Member Functions</a> + </h5> +<div class="informaltable"><table class="table"> +<colgroup> +<col> +<col> +</colgroup> +<thead><tr> +<th> + <p> + Name + </p> + </th> +<th> + <p> + Description + </p> + </th> +</tr></thead> +<tbody> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/get_implementation.html" title="basic_waitable_timer::get_implementation"><span class="bold"><strong>get_implementation</strong></span></a> + </p> + </td> +<td> + <p> + Get the underlying implementation of the I/O object. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/get_service.html" title="basic_waitable_timer::get_service"><span class="bold"><strong>get_service</strong></span></a> + </p> + </td> +<td> + <p> + Get the service associated with the I/O object. + </p> + </td> +</tr> +</tbody> +</table></div> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h3"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.protected_data_members"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.protected_data_members">Protected + Data Members</a> + </h5> +<div class="informaltable"><table class="table"> +<colgroup> +<col> +<col> +</colgroup> +<thead><tr> +<th> + <p> + Name + </p> + </th> +<th> + <p> + Description + </p> + </th> +</tr></thead> +<tbody> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/implementation.html" title="basic_waitable_timer::implementation"><span class="bold"><strong>implementation</strong></span></a> + </p> + </td> +<td> + <p> + (Deprecated: Use get_implementation().) The underlying implementation + of the I/O object. + </p> + </td> +</tr> +<tr> +<td> + <p> + <a class="link" href="basic_waitable_timer/service.html" title="basic_waitable_timer::service"><span class="bold"><strong>service</strong></span></a> + </p> + </td> +<td> + <p> + (Deprecated: Use get_service().) The service associated with the + I/O object. + </p> + </td> +</tr> +</tbody> +</table></div> +<p> + The <a class="link" href="basic_waitable_timer.html" title="basic_waitable_timer"><code class="computeroutput"><span class="identifier">basic_waitable_timer</span></code></a> class template + provides the ability to perform a blocking or asynchronous wait for a timer + to expire. + </p> +<p> + A waitable timer is always in one of two states: "expired" or "not + expired". If the <code class="computeroutput"><span class="identifier">wait</span><span class="special">()</span></code> or <code class="computeroutput"><span class="identifier">async_wait</span><span class="special">()</span></code> function is called on an expired timer, + the wait operation will complete immediately. + </p> +<p> + Most applications will use one of the <a class="link" href="steady_timer.html" title="steady_timer"><code class="computeroutput"><span class="identifier">steady_timer</span></code></a>, <a class="link" href="system_timer.html" title="system_timer"><code class="computeroutput"><span class="identifier">system_timer</span></code></a> or <a class="link" href="high_resolution_timer.html" title="high_resolution_timer"><code class="computeroutput"><span class="identifier">high_resolution_timer</span></code></a> typedefs. + </p> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h4"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.remarks"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.remarks">Remarks</a> + </h5> +<p> + This waitable timer functionality is for use with the C++11 standard library's + <code class="computeroutput"><span class="special"><</span><span class="identifier">chrono</span><span class="special">></span></code> facility, or with the Boost.Chrono library. + </p> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h5"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.thread_safety"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.thread_safety">Thread + Safety</a> + </h5> +<p> + <span class="emphasis"><em>Distinct</em></span> <span class="emphasis"><em>objects:</em></span> Safe. + </p> +<p> + <span class="emphasis"><em>Shared</em></span> <span class="emphasis"><em>objects:</em></span> Unsafe. + </p> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h6"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.examples"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.examples">Examples</a> + </h5> +<p> + Performing a blocking wait (C++11): + </p> +<pre class="programlisting"><span class="comment">// Construct a timer without setting an expiry time.</span> +<span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">steady_timer</span> <span class="identifier">timer</span><span class="special">(</span><span class="identifier">io_service</span><span class="special">);</span> + +<span class="comment">// Set an expiry time relative to now.</span> +<span class="identifier">timer</span><span class="special">.</span><span class="identifier">expires_from_now</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">chrono</span><span class="special">::</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">5</span><span class="special">));</span> + +<span class="comment">// Wait for the timer to expire.</span> +<span class="identifier">timer</span><span class="special">.</span><span class="identifier">wait</span><span class="special">();</span> +</pre> +<p> + Performing an asynchronous wait (C++11): + </p> +<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">handler</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">system</span><span class="special">::</span><span class="identifier">error_code</span><span class="special">&</span> <span class="identifier">error</span><span class="special">)</span> +<span class="special">{</span> + <span class="keyword">if</span> <span class="special">(!</span><span class="identifier">error</span><span class="special">)</span> + <span class="special">{</span> + <span class="comment">// Timer expired.</span> + <span class="special">}</span> +<span class="special">}</span> + +<span class="special">...</span> + +<span class="comment">// Construct a timer with an absolute expiry time.</span> +<span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">steady_timer</span> <span class="identifier">timer</span><span class="special">(</span><span class="identifier">io_service</span><span class="special">,</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">chrono</span><span class="special">::</span><span class="identifier">steady_clock</span><span class="special">::</span><span class="identifier">now</span><span class="special">()</span> <span class="special">+</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">chrono</span><span class="special">::</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">60</span><span class="special">));</span> + +<span class="comment">// Start an asynchronous wait.</span> +<span class="identifier">timer</span><span class="special">.</span><span class="identifier">async_wait</span><span class="special">(</span><span class="identifier">handler</span><span class="special">);</span> +</pre> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h7"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.changing_an_active_waitable_timer_s_expiry_time"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.changing_an_active_waitable_timer_s_expiry_time">Changing + an active waitable timer's expiry time</a> + </h5> +<p> + Changing the expiry time of a timer while there are pending asynchronous + waits causes those wait operations to be cancelled. To ensure that the action + associated with the timer is performed only once, use something like this: + used: + </p> +<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">on_some_event</span><span class="special">()</span> +<span class="special">{</span> + <span class="keyword">if</span> <span class="special">(</span><span class="identifier">my_timer</span><span class="special">.</span><span class="identifier">expires_from_now</span><span class="special">(</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">5</span><span class="special">))</span> <span class="special">></span> <span class="number">0</span><span class="special">)</span> + <span class="special">{</span> + <span class="comment">// We managed to cancel the timer. Start new asynchronous wait.</span> + <span class="identifier">my_timer</span><span class="special">.</span><span class="identifier">async_wait</span><span class="special">(</span><span class="identifier">on_timeout</span><span class="special">);</span> + <span class="special">}</span> + <span class="keyword">else</span> + <span class="special">{</span> + <span class="comment">// Too late, timer has already expired!</span> + <span class="special">}</span> +<span class="special">}</span> + +<span class="keyword">void</span> <span class="identifier">on_timeout</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">system</span><span class="special">::</span><span class="identifier">error_code</span><span class="special">&</span> <span class="identifier">e</span><span class="special">)</span> +<span class="special">{</span> + <span class="keyword">if</span> <span class="special">(</span><span class="identifier">e</span> <span class="special">!=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">error</span><span class="special">::</span><span class="identifier">operation_aborted</span><span class="special">)</span> + <span class="special">{</span> + <span class="comment">// Timer was not cancelled, take necessary action.</span> + <span class="special">}</span> +<span class="special">}</span> +</pre> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + The <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">basic_waitable_timer</span><span class="special">::</span><span class="identifier">expires_from_now</span><span class="special">()</span></code> + function cancels any pending asynchronous waits, and returns the number + of asynchronous waits that were cancelled. If it returns 0 then you were + too late and the wait handler has already been executed, or will soon + be executed. If it returns 1 then the wait handler was successfully cancelled. + </li> +<li class="listitem"> + If a wait handler is cancelled, the boost::system::error_code passed + to it contains the value <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">error</span><span class="special">::</span><span class="identifier">operation_aborted</span></code>. + </li> +</ul></div> +<p> + This typedef uses the C++11 <code class="computeroutput"><span class="special"><</span><span class="identifier">chrono</span><span class="special">></span></code> + standard library facility, if available. Otherwise, it may use the Boost.Chrono + library. To explicitly utilise Boost.Chrono, use the <a class="link" href="basic_waitable_timer.html" title="basic_waitable_timer"><code class="computeroutput"><span class="identifier">basic_waitable_timer</span></code></a> template directly: + </p> +<pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">basic_waitable_timer</span><span class="special"><</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">chrono</span><span class="special">::</span><span class="identifier">high_resolution_clock</span><span class="special">></span> <span class="identifier">timer</span><span class="special">;</span> +</pre> +<h5> +<a name="boost_asio.reference.high_resolution_timer.h8"></a> + <span class="phrase"><a name="boost_asio.reference.high_resolution_timer.requirements"></a></span><a class="link" href="high_resolution_timer.html#boost_asio.reference.high_resolution_timer.requirements">Requirements</a> + </h5> +<p> + <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/high_resolution_timer.hpp</code> + </p> +<p> + <span class="emphasis"><em>Convenience header: </em></span>None + </p> +</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 © 2003-2017 Christopher M. Kohlhoff<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="has_service.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.html"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../boost_asio.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="invalid_service_owner.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |