Insane_DNS/libraries/asio-1.28.1/doc/asio/reference/async_connect/overload2.html

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<div class="titlepage"><div><div><h4 class="title">
<a name="asio.reference.async_connect.overload2"></a><a class="link" href="overload2.html" title="async_connect (2 of 6 overloads)">async_connect
(2 of 6 overloads)</a>
</h4></div></div></div>
<p>
(Deprecated: Use range overload.) Asynchronously establishes a socket connection
by trying each endpoint in a sequence.
</p>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
<span class="keyword">typename</span> <a class="link" href="../Protocol.html" title="Protocol requirements">Protocol</a><span class="special">,</span>
<span class="keyword">typename</span> <a class="link" href="../Executor1.html" title="Executor requirements">Executor</a><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">Iterator</span><span class="special">,</span>
<span class="keyword">typename</span> <a class="link" href="../IteratorConnectToken.html" title="Iterator connect token requirements">IteratorConnectToken</a> <span class="special">=</span> <a class="link" href="../asynchronous_operations.html#asio.reference.asynchronous_operations.default_completion_tokens"><span class="emphasis"><em>DEFAULT</em></span></a><span class="special">&gt;</span>
<a class="link" href="../asynchronous_operations.html#asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type"><span class="emphasis"><em>DEDUCED</em></span></a> <span class="identifier">async_connect</span><span class="special">(</span>
<span class="identifier">basic_socket</span><span class="special">&lt;</span> <span class="identifier">Protocol</span><span class="special">,</span> <span class="identifier">Executor</span> <span class="special">&gt;</span> <span class="special">&amp;</span> <span class="identifier">s</span><span class="special">,</span>
<span class="identifier">Iterator</span> <span class="identifier">begin</span><span class="special">,</span>
<span class="identifier">IteratorConnectToken</span> <span class="special">&amp;&amp;</span> <span class="identifier">token</span> <span class="special">=</span> <a class="link" href="../asynchronous_operations.html#asio.reference.asynchronous_operations.default_completion_tokens"><span class="emphasis"><em>DEFAULT</em></span></a><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">constraint</span><span class="special">&lt;!</span><span class="identifier">is_endpoint_sequence</span><span class="special">&lt;</span> <span class="identifier">Iterator</span> <span class="special">&gt;::</span><span class="identifier">value</span> <span class="special">&gt;::</span><span class="identifier">type</span> <span class="special">=</span> <span class="number">0</span><span class="special">);</span>
</pre>
<p>
This function attempts to connect a socket to one of a sequence of endpoints.
It does this by repeated calls to the socket's <code class="computeroutput"><span class="identifier">async_connect</span></code>
member function, once for each endpoint in the sequence, until a connection
is successfully established. It is an initiating function for an <a class="link" href="../../overview/model/async_ops.html" title="Asynchronous Operations">asynchronous operation</a>,
and always returns immediately.
</p>
<h6>
<a name="asio.reference.async_connect.overload2.h0"></a>
<span><a name="asio.reference.async_connect.overload2.parameters"></a></span><a class="link" href="overload2.html#asio.reference.async_connect.overload2.parameters">Parameters</a>
</h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl>
<dt><span class="term">s</span></dt>
<dd><p>
The socket to be connected. If the socket is already open, it will
be closed.
</p></dd>
<dt><span class="term">begin</span></dt>
<dd><p>
An iterator pointing to the start of a sequence of endpoints.
</p></dd>
<dt><span class="term">token</span></dt>
<dd>
<p>
The <a class="link" href="../../overview/model/completion_tokens.html" title="Completion Tokens">completion
token</a> that will be used to produce a completion handler, which
will be called when the connect completes. Potential completion tokens
include <a class="link" href="../use_future.html" title="use_future"><code class="computeroutput"><span class="identifier">use_future</span></code></a>,
<a class="link" href="../use_awaitable.html" title="use_awaitable"><code class="computeroutput"><span class="identifier">use_awaitable</span></code></a>,
<a class="link" href="../yield_context.html" title="yield_context"><code class="computeroutput"><span class="identifier">yield_context</span></code></a>,
or a function object with the correct completion signature. The function
signature of the completion handler must be:
</p>
<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">handler</span><span class="special">(</span>
<span class="comment">// Result of operation. if the sequence is empty, set to</span>
<span class="comment">// asio::error::not_found. Otherwise, contains the</span>
<span class="comment">// error from the last connection attempt.</span>
<span class="keyword">const</span> <span class="identifier">asio</span><span class="special">::</span><span class="identifier">error_code</span><span class="special">&amp;</span> <span class="identifier">error</span><span class="special">,</span>
<span class="comment">// On success, an iterator denoting the successfully</span>
<span class="comment">// connected endpoint. Otherwise, the end iterator.</span>
<span class="identifier">Iterator</span> <span class="identifier">iterator</span>
<span class="special">);</span>
</pre>
<p>
Regardless of whether the asynchronous operation completes immediately
or not, the completion handler will not be invoked from within this
function. On immediate completion, invocation of the handler will
be performed in a manner equivalent to using <a class="link" href="../post.html" title="post"><code class="computeroutput"><span class="identifier">post</span></code></a>.
</p>
</dd>
</dl>
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<h6>
<a name="asio.reference.async_connect.overload2.h1"></a>
<span><a name="asio.reference.async_connect.overload2.completion_signature"></a></span><a class="link" href="overload2.html#asio.reference.async_connect.overload2.completion_signature">Completion
Signature</a>
</h6>
<pre class="programlisting"><span class="keyword">void</span><span class="special">(</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">error_code</span><span class="special">,</span> <span class="identifier">Iterator</span><span class="special">)</span>
</pre>
<h6>
<a name="asio.reference.async_connect.overload2.h2"></a>
<span><a name="asio.reference.async_connect.overload2.remarks"></a></span><a class="link" href="overload2.html#asio.reference.async_connect.overload2.remarks">Remarks</a>
</h6>
<p>
This overload assumes that a default constructed object of type <code class="computeroutput"><span class="identifier">Iterator</span></code> represents the end of the sequence.
This is a valid assumption for iterator types such as <code class="computeroutput"><span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span class="identifier">resolver</span><span class="special">::</span><span class="identifier">iterator</span></code>.
</p>
<h6>
<a name="asio.reference.async_connect.overload2.h3"></a>
<span><a name="asio.reference.async_connect.overload2.per_operation_cancellation"></a></span><a class="link" href="overload2.html#asio.reference.async_connect.overload2.per_operation_cancellation">Per-Operation
Cancellation</a>
</h6>
<p>
This asynchronous operation supports cancellation for the following <a class="link" href="../cancellation_type.html" title="cancellation_type"><code class="computeroutput"><span class="identifier">cancellation_type</span></code></a>
values:
</p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
<code class="computeroutput"><span class="identifier">cancellation_type</span><span class="special">::</span><span class="identifier">terminal</span></code>
</li>
<li class="listitem">
<code class="computeroutput"><span class="identifier">cancellation_type</span><span class="special">::</span><span class="identifier">partial</span></code>
</li>
</ul></div>
<p>
if they are also supported by the socket's <code class="computeroutput"><span class="identifier">async_connect</span></code>
operation.
</p>
</div>
<div class="copyright-footer">Copyright © 2003-2023 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>)
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