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514 lines
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<title>Platform-Specific Implementation Notes</title>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_asio.overview.implementation"></a><a class="link" href="implementation.html" title="Platform-Specific Implementation Notes">Platform-Specific
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Implementation Notes</a>
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</h3></div></div></div>
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<p>
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This section lists platform-specific implementation details, such as the
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default demultiplexing mechanism, the number of threads created internally,
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and when threads are created.
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</p>
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<h5>
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<a name="boost_asio.overview.implementation.h0"></a>
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<span class="phrase"><a name="boost_asio.overview.implementation.linux_kernel_2_4"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.linux_kernel_2_4">Linux
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Kernel 2.4</a>
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</h5>
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<p>
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Demultiplexing mechanism:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Uses <code class="computeroutput">select</code> for demultiplexing. This means that the number
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of file descriptors in the process cannot be permitted to exceed <code class="computeroutput">FD_SETSIZE</code>.
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</li></ul></div>
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<p>
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Threads:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
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<li class="listitem">
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Demultiplexing using <code class="computeroutput">select</code> is performed in one of the threads
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that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
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<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
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</li>
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<li class="listitem">
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An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
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<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
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</li>
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</ul></div>
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<p>
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Scatter-Gather:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
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single operation.
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</li></ul></div>
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<h5>
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<a name="boost_asio.overview.implementation.h1"></a>
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<span class="phrase"><a name="boost_asio.overview.implementation.linux_kernel_2_6"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.linux_kernel_2_6">Linux
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Kernel 2.6</a>
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</h5>
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<p>
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Demultiplexing mechanism:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Uses <code class="computeroutput">epoll</code> for demultiplexing.
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</li></ul></div>
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<p>
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Threads:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
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<li class="listitem">
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Demultiplexing using <code class="computeroutput">epoll</code> is performed in one of the threads
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that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
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<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
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</li>
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<li class="listitem">
|
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An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
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<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
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</li>
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</ul></div>
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<p>
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|
Scatter-Gather:
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</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
|
|
single operation.
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</li></ul></div>
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<h5>
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<a name="boost_asio.overview.implementation.h2"></a>
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<span class="phrase"><a name="boost_asio.overview.implementation.solaris"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.solaris">Solaris</a>
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</h5>
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<p>
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Demultiplexing mechanism:
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Uses <code class="literal">/dev/poll</code> for demultiplexing.
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</li></ul></div>
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<p>
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Threads:
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</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
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<li class="listitem">
|
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Demultiplexing using <code class="literal">/dev/poll</code> is performed in one
|
|
of the threads that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
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<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
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</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
|
|
single operation.
|
|
</li></ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h3"></a>
|
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<span class="phrase"><a name="boost_asio.overview.implementation.qnx_neutrino"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.qnx_neutrino">QNX
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Neutrino</a>
|
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</h5>
|
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<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
Uses <code class="computeroutput">select</code> for demultiplexing. This means that the number
|
|
of file descriptors in the process cannot be permitted to exceed <code class="computeroutput">FD_SETSIZE</code>.
|
|
</li></ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Demultiplexing using <code class="computeroutput">select</code> is performed in one of the threads
|
|
that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
|
<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
|
|
single operation.
|
|
</li></ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h4"></a>
|
|
<span class="phrase"><a name="boost_asio.overview.implementation.mac_os_x"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.mac_os_x">Mac
|
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OS X</a>
|
|
</h5>
|
|
<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
Uses <code class="computeroutput">kqueue</code> for demultiplexing.
|
|
</li></ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Demultiplexing using <code class="computeroutput">kqueue</code> is performed in one of the threads
|
|
that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
|
<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
|
|
single operation.
|
|
</li></ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h5"></a>
|
|
<span class="phrase"><a name="boost_asio.overview.implementation.freebsd"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.freebsd">FreeBSD</a>
|
|
</h5>
|
|
<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
Uses <code class="computeroutput">kqueue</code> for demultiplexing.
|
|
</li></ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Demultiplexing using <code class="computeroutput">kqueue</code> is performed in one of the threads
|
|
that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
|
<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
|
|
single operation.
|
|
</li></ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h6"></a>
|
|
<span class="phrase"><a name="boost_asio.overview.implementation.aix"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.aix">AIX</a>
|
|
</h5>
|
|
<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
Uses <code class="computeroutput">select</code> for demultiplexing. This means that the number
|
|
of file descriptors in the process cannot be permitted to exceed <code class="computeroutput">FD_SETSIZE</code>.
|
|
</li></ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Demultiplexing using <code class="computeroutput">select</code> is performed in one of the threads
|
|
that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
|
<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
|
|
single operation.
|
|
</li></ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h7"></a>
|
|
<span class="phrase"><a name="boost_asio.overview.implementation.hp_ux"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.hp_ux">HP-UX</a>
|
|
</h5>
|
|
<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
Uses <code class="computeroutput">select</code> for demultiplexing. This means that the number
|
|
of file descriptors in the process cannot be permitted to exceed <code class="computeroutput">FD_SETSIZE</code>.
|
|
</li></ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Demultiplexing using <code class="computeroutput">select</code> is performed in one of the threads
|
|
that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
|
<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
|
|
single operation.
|
|
</li></ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h8"></a>
|
|
<span class="phrase"><a name="boost_asio.overview.implementation.tru64"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.tru64">Tru64</a>
|
|
</h5>
|
|
<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
Uses <code class="computeroutput">select</code> for demultiplexing. This means that the number
|
|
of file descriptors in the process cannot be permitted to exceed <code class="computeroutput">FD_SETSIZE</code>.
|
|
</li></ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Demultiplexing using <code class="computeroutput">select</code> is performed in one of the threads
|
|
that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
|
<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
At most <code class="computeroutput">min(64,IOV_MAX)</code> buffers may be transferred in a
|
|
single operation.
|
|
</li></ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h9"></a>
|
|
<span class="phrase"><a name="boost_asio.overview.implementation.windows_95__98_and_me"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.windows_95__98_and_me">Windows
|
|
95, 98 and Me</a>
|
|
</h5>
|
|
<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
Uses <code class="computeroutput">select</code> for demultiplexing.
|
|
</li></ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Demultiplexing using <code class="computeroutput">select</code> is performed in one of the threads
|
|
that calls <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
|
<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
For sockets, at most 16 buffers may be transferred in a single operation.
|
|
</li></ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h10"></a>
|
|
<span class="phrase"><a name="boost_asio.overview.implementation.windows_nt__2000__xp__2003__vista__7_and_8"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.windows_nt__2000__xp__2003__vista__7_and_8">Windows
|
|
NT, 2000, XP, 2003, Vista, 7 and 8</a>
|
|
</h5>
|
|
<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Uses overlapped I/O and I/O completion ports for all asynchronous socket
|
|
operations except for asynchronous connect.
|
|
</li>
|
|
<li class="listitem">
|
|
Uses <code class="computeroutput">select</code> for emulating asynchronous connect.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Demultiplexing using I/O completion ports is performed in all threads
|
|
that call <code class="computeroutput">io_context::run()</code>, <code class="computeroutput">io_context::run_one()</code>,
|
|
<code class="computeroutput">io_context::poll()</code> or <code class="computeroutput">io_context::poll_one()</code>.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to trigger timers.
|
|
This thread is created on construction of the first <code class="computeroutput">basic_deadline_timer</code>
|
|
or <code class="computeroutput">basic_waitable_timer</code> objects.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> may be used for <code class="computeroutput">select</code>
|
|
demultiplexing. This thread is created on the first call to:
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; ">
|
|
<li class="listitem">
|
|
A socket <code class="computeroutput">async_wait()</code> function, except when using
|
|
<code class="computeroutput">wait_read</code> on a stream-oriented socket. (For <code class="computeroutput">wait_read</code>
|
|
on a stream-oriented socket, the overlapped I/O operation <code class="computeroutput">WSARecv</code>
|
|
is used and no additional thread is required.)
|
|
</li>
|
|
<li class="listitem">
|
|
A socket <code class="computeroutput">async_connect()</code> operation, if the overlapped
|
|
I/O operation <code class="computeroutput">ConnectEx</code> is unavailable. (On recent
|
|
versions of Windows, <code class="computeroutput">ConnectEx</code> is used and no additional
|
|
thread is required.)
|
|
</li>
|
|
</ul></div>
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to emulate asynchronous
|
|
host resolution. This thread is created on the first call to either
|
|
<code class="computeroutput">ip::tcp::resolver::async_resolve()</code> or <code class="computeroutput">ip::udp::resolver::async_resolve()</code>.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
For sockets, at most 64 buffers may be transferred in a single operation.
|
|
</li>
|
|
<li class="listitem">
|
|
For stream-oriented handles, only one buffer may be transferred in a
|
|
single operation.
|
|
</li>
|
|
</ul></div>
|
|
<h5>
|
|
<a name="boost_asio.overview.implementation.h11"></a>
|
|
<span class="phrase"><a name="boost_asio.overview.implementation.windows_runtime"></a></span><a class="link" href="implementation.html#boost_asio.overview.implementation.windows_runtime">Windows
|
|
Runtime</a>
|
|
</h5>
|
|
<p>
|
|
Boost.Asio provides limited support for the Windows Runtime. It requires
|
|
that the language extensions be enabled. Due to the restricted facilities
|
|
exposed by the Windows Runtime API, the support comes with the following
|
|
caveats:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
The core facilities such as the <code class="computeroutput">io_context</code>, <code class="computeroutput">strand</code>,
|
|
buffers, composed operations, timers, etc., should all work as normal.
|
|
</li>
|
|
<li class="listitem">
|
|
For sockets, only client-side TCP is supported.
|
|
</li>
|
|
<li class="listitem">
|
|
Explicit binding of a client-side TCP socket is not supported.
|
|
</li>
|
|
<li class="listitem">
|
|
The <code class="computeroutput">cancel()</code> function is not supported for sockets. Asynchronous
|
|
operations may only be cancelled by closing the socket.
|
|
</li>
|
|
<li class="listitem">
|
|
Operations that use <code class="computeroutput">null_buffers</code> are not supported.
|
|
</li>
|
|
<li class="listitem">
|
|
Only <code class="computeroutput">tcp::no_delay</code> and <code class="computeroutput">socket_base::keep_alive</code>
|
|
options are supported.
|
|
</li>
|
|
<li class="listitem">
|
|
Resolvers do not support service names, only numbers. I.e. you must use
|
|
"80" rather than "http".
|
|
</li>
|
|
<li class="listitem">
|
|
Most resolver query flags have no effect.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Demultiplexing mechanism:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
Uses the <code class="computeroutput">Windows::Networking::Sockets::StreamSocket</code> class
|
|
to implement asynchronous TCP socket operations.
|
|
</li></ul></div>
|
|
<p>
|
|
Threads:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Event completions are delivered to the Windows thread pool and posted
|
|
to the <code class="computeroutput">io_context</code> for the handler to be executed.
|
|
</li>
|
|
<li class="listitem">
|
|
An additional thread per <code class="computeroutput">io_context</code> is used to trigger timers.
|
|
This thread is created on construction of the first timer objects.
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Scatter-Gather:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
For sockets, at most one buffer may be transferred in a single operation.
|
|
</li></ul></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 © 2003-2021 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>
|
|
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|
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