Insane_DNS/libraries/asio-1.28.1/doc/asio/reference/connect/overload9.html

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<div class="titlepage"><div><div><h4 class="title">
<a name="asio.reference.connect.overload9"></a><a class="link" href="overload9.html" title="connect (9 of 12 overloads)">connect (9 of 12
overloads)</a>
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<p>
(Deprecated: Use range overload.) 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="../ConnectCondition.html" title="Connect condition requirements">ConnectCondition</a><span class="special">&gt;</span>
<span class="identifier">Iterator</span> <span class="identifier">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">ConnectCondition</span> <span class="identifier">connect_condition</span><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">connect</span></code>
member function, once for each endpoint in the sequence, until a connection
is successfully established.
</p>
<h6>
<a name="asio.reference.connect.overload9.h0"></a>
<span><a name="asio.reference.connect.overload9.parameters"></a></span><a class="link" href="overload9.html#asio.reference.connect.overload9.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">connect_condition</span></dt>
<dd>
<p>
A function object that is called prior to each connection attempt.
The signature of the function object must be:
</p>
<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">connect_condition</span><span class="special">(</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">ec</span><span class="special">,</span>
<span class="keyword">const</span> <span class="keyword">typename</span> <span class="identifier">Protocol</span><span class="special">::</span><span class="identifier">endpoint</span><span class="special">&amp;</span> <span class="identifier">next</span><span class="special">);</span>
</pre>
<p>
The <code class="computeroutput"><span class="identifier">ec</span></code> parameter
contains the result from the most recent connect operation. Before
the first connection attempt, <code class="computeroutput"><span class="identifier">ec</span></code>
is always set to indicate success. The <code class="computeroutput"><span class="identifier">next</span></code>
parameter is the next endpoint to be tried. The function object should
return true if the next endpoint should be tried, and false if it
should be skipped.
</p>
</dd>
</dl>
</div>
<h6>
<a name="asio.reference.connect.overload9.h1"></a>
<span><a name="asio.reference.connect.overload9.return_value"></a></span><a class="link" href="overload9.html#asio.reference.connect.overload9.return_value">Return
Value</a>
</h6>
<p>
On success, an iterator denoting the successfully connected endpoint. Otherwise,
the end iterator.
</p>
<h6>
<a name="asio.reference.connect.overload9.h2"></a>
<span><a name="asio.reference.connect.overload9.exceptions"></a></span><a class="link" href="overload9.html#asio.reference.connect.overload9.exceptions">Exceptions</a>
</h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl>
<dt><span class="term">asio::system_error</span></dt>
<dd><p>
Thrown on failure. If the sequence is empty, the associated <code class="computeroutput"><span class="identifier">error_code</span></code> is <code class="computeroutput"><span class="identifier">asio</span><span class="special">::</span><span class="identifier">error</span><span class="special">::</span><span class="identifier">not_found</span></code>.
Otherwise, contains the error from the last connection attempt.
</p></dd>
</dl>
</div>
<h6>
<a name="asio.reference.connect.overload9.h3"></a>
<span><a name="asio.reference.connect.overload9.remarks"></a></span><a class="link" href="overload9.html#asio.reference.connect.overload9.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>
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<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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