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<body class="manpage">
<div id="header">
<h1>
nn_send(3) Manual Page
</h1>
<h2>NAME</h2>
<div class="sectionbody">
<p>nn_send -
   send a message
</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_send (int <em>s</em>, const void <em>*buf</em>, size_t <em>len</em>, int <em>flags</em>);</strong></p></div>
</div>
</div>
<div class="sect1">
<h2 id="_description">DESCRIPTION</h2>
<div class="sectionbody">
<div class="paragraph"><p>The function will send a message containing the data from buffer pointed to
by <em>buf</em> parameter to the socket <em>s</em>. The message will be <em>len</em> bytes long.</p></div>
<div class="paragraph"><p>Alternatively, to send a buffer allocated by <a href="nn_allocmsg.3.html">nn_allocmsg(3)</a> function
set the buf parameter to point to the pointer to the buffer and <em>len</em> parameter
to <em>NN_MSG</em> constant. In this case a successful call to <em>nn_send</em> will
deallocate the buffer. Trying to deallocate it afterwards will result in
undefined behaviour.</p></div>
<div class="paragraph"><p>Which of the peers the message will be sent to is determined by
the particular socket type.</p></div>
<div class="paragraph"><p>The <em>flags</em> argument is a combination of the flags defined below:</p></div>
<div class="dlist"><dl>
<dt class="hdlist1">
<strong>NN_DONTWAIT</strong>
</dt>
<dd>
<p>
Specifies that the operation should be performed in non-blocking mode. If the
message cannot be sent straight away, the function will fail with <em>errno</em> set
to EAGAIN.
</p>
</dd>
</dl></div>
</div>
</div>
<div class="sect1">
<h2 id="_return_value">RETURN VALUE</h2>
<div class="sectionbody">
<div class="paragraph"><p>If the function succeeds, the number of bytes in the message is returned.
Otherwise, -1 is returned and <em>errno</em> is set to to one of the
values defined below.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_errors">ERRORS</h2>
<div class="sectionbody">
<div class="dlist"><dl>
<dt class="hdlist1">
<strong>EFAULT</strong>
</dt>
<dd>
<p>
<em>buf</em> is NULL or <em>len</em> is NN_MSG and the message pointer (pointed to by
<em>buf</em>) is NULL.
</p>
</dd>
<dt class="hdlist1">
<strong>EBADF</strong>
</dt>
<dd>
<p>
The provided socket is invalid.
</p>
</dd>
<dt class="hdlist1">
<strong>ENOTSUP</strong>
</dt>
<dd>
<p>
The operation is not supported by this socket type.
</p>
</dd>
<dt class="hdlist1">
<strong>EFSM</strong>
</dt>
<dd>
<p>
The operation cannot be performed on this socket at the moment because the socket
is not in the appropriate state.  This error may occur with socket types that
switch between several states.
</p>
</dd>
<dt class="hdlist1">
<strong>EAGAIN</strong>
</dt>
<dd>
<p>
Non-blocking mode was requested and the message cannot be sent at the moment.
</p>
</dd>
<dt class="hdlist1">
<strong>EINTR</strong>
</dt>
<dd>
<p>
The operation was interrupted by delivery of a signal before the message was
sent.
</p>
</dd>
<dt class="hdlist1">
<strong>ETIMEDOUT</strong>
</dt>
<dd>
<p>
Individual socket types may define their own specific timeouts. If such timeout
is hit, this error will be returned.
</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="paragraph"><p>Using data directly:</p></div>
<div class="listingblock">
<div class="content">
<pre><tt>nbytes = nn_send (s, "ABC", 3, 0);
assert (nbytes == 3);</tt></pre>
</div></div>
<div class="paragraph"><p>Using a pre-allocated message buffer:</p></div>
<div class="listingblock">
<div class="content">
<pre><tt>void *msg = nn_allocmsg(3, 0);
strncpy(msg, "ABC", 3);
nbytes = nn_send (s, &amp;msg, NN_MSG, 0);
assert (nbytes == 3);</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_recv.3.html">nn_recv(3)</a>
<a href="nn_sendmsg.3.html">nn_sendmsg(3)</a>
<a href="nn_socket.3.html">nn_socket(3)</a>
<a href="nanomsg.7.html">nanomsg(7)</a></p></div>
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<h2 id="_authors">AUTHORS</h2>
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<div class="paragraph"><p>Martin Sustrik &lt;<a href="mailto:sustrik@250bpm.com">sustrik@250bpm.com</a>&gt;</p></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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