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<body class="manpage">
<div id="header">
<h1>
nn_socket(3) Manual Page
</h1>
<h2>NAME</h2>
<div class="sectionbody">
<p>nn_socket -
   create an SP socket
</p>
</div>
</div>
<div id="content">
<div class="sect1">
<h2 id="_synopsis">SYNOPSIS</h2>
<div class="sectionbody">
<div class="paragraph"><p><strong>#include &lt;nanomsg/nn.h&gt;</strong></p></div>
<div class="paragraph"><p><strong>int nn_socket (int <em>domain</em>, int <em>protocol</em>);</strong></p></div>
</div>
</div>
<div class="sect1">
<h2 id="_description">DESCRIPTION</h2>
<div class="sectionbody">
<div class="paragraph"><p>Creates an SP socket with specified <em>domain</em> and <em>protocol</em>. Returns a file
descriptor for the newly created socket.</p></div>
<div class="paragraph"><p>Following domains are defined at the moment:</p></div>
<div class="dlist"><dl>
<dt class="hdlist1">
<strong>AF_SP</strong>
</dt>
<dd>
<p>
Standard full-blown SP socket.
</p>
</dd>
<dt class="hdlist1">
<strong>AF_SP_RAW</strong>
</dt>
<dd>
<p>
Raw SP socket. Raw sockets omit the end-to-end functionality found in AF_SP
sockets and thus can be used to implement intermediary devices in SP topologies.
</p>
</dd>
</dl></div>
<div class="paragraph"><p><em>protocol</em> parameter defines the type of the socket, which in turn determines
the exact semantics of the socket. Check manual pages for individual SP
protocols to get the list of available socket types.</p></div>
<div class="paragraph"><p>The newly created socket is initially not associated with any endpoints.
In order to establish a message flow at least one endpoint has to be added
to the socket using <a href="nn_bind.3.html">nn_bind(3)</a> or <a href="nn_connect.3.html">nn_connect(3)</a>
function.</p></div>
<div class="paragraph"><p>Also note that <em>type</em> argument as found in standard <em>socket(2)</em> function is
omitted from <em>nn_socket</em>. All the SP sockets are message-based and thus of
<em>SOCK_SEQPACKET</em> type.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_return_value">RETURN VALUE</h2>
<div class="sectionbody">
<div class="paragraph"><p>If the function succeeds file descriptor of the new socket is returned.
Otherwise, -1 is returned and <em>errno</em> is set to to one of
the values defined below.</p></div>
<div class="paragraph"><p>Note that file descriptors returned by <em>nn_socket</em> function are not standard
file descriptors and will exhibit undefined behaviour when used with system
functions. Moreover, it may happen that a system file descriptor and file
descriptor of an SP socket will incidentally collide (be equal).</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_errors">ERRORS</h2>
<div class="sectionbody">
<div class="dlist"><dl>
<dt class="hdlist1">
<strong>EAFNOSUPPORT</strong>
</dt>
<dd>
<p>
Specified address family is not supported.
</p>
</dd>
<dt class="hdlist1">
<strong>EINVAL</strong>
</dt>
<dd>
<p>
Unknown protocol.
</p>
</dd>
<dt class="hdlist1">
<strong>EMFILE</strong>
</dt>
<dd>
<p>
The limit on the total number of open SP sockets or OS limit for file
descriptors has been reached.
</p>
</dd>
<dt class="hdlist1">
<strong>ETERM</strong>
</dt>
<dd>
<p>
The library is terminating.
</p>
</dd>
</dl></div>
</div>
</div>
<div class="sect1">
<h2 id="_example">EXAMPLE</h2>
<div class="sectionbody">
<div class="listingblock">
<div class="content">
<pre><tt>int s = nn_socket (AF_SP, NN_PUB);
assert (s &gt;= 0);</tt></pre>
</div></div>
</div>
</div>
<div class="sect1">
<h2 id="_see_also">SEE ALSO</h2>
<div class="sectionbody">
<div class="paragraph"><p><a href="nn_pubsub.7.html">nn_pubsub(7)</a>
<a href="nn_reqrep.7.html">nn_reqrep(7)</a>
<a href="nn_pipeline.7.html">nn_pipeline(7)</a>
<a href="nn_survey.7.html">nn_survey(7)</a>
<a href="nn_bus.7.html">nn_bus(7)</a>
<a href="nn_bind.3.html">nn_bind(3)</a>
<a href="nn_connect.3.html">nn_connect(3)</a>
<a href="nn_close.3.html">nn_close(3)</a>
<a href="nanomsg.7.html">nanomsg(7)</a></p></div>
</div>
</div>
<div class="sect1">
<h2 id="_authors">AUTHORS</h2>
<div class="sectionbody">
<div class="paragraph"><p>Martin Sustrik &lt;<a href="mailto:sustrik@250bpm.com">sustrik@250bpm.com</a>&gt;</p></div>
</div>
</div>
</div>
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nanomsg 0.3-beta-2-g8ae44eb-dirty<br />
Last updated 2014-03-04 23:29:50 CET
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