path: root/man/tip/nn_errno.3compat.html

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version: tip
layout: manpage_v2
title: nn_errno(3compat)
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<h1>nn_errno(3compat)</h1>
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<h2 id="_name">NAME</h2>
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<p>nn_errno - return most recent error (compatible API)</p>
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<h2 id="_synopsis">SYNOPSIS</h2>
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<pre class="pygments highlight"><code data-lang="c"><span></span><span class="tok-cp">#include</span><span class="tok-w"> </span><span class="tok-cpf">&lt;nanomsg/nn.h&gt;</span>

<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-nf">nn_errno</span><span class="tok-p">(</span><span class="tok-kt">void</span><span class="tok-p">);</span></code></pre>
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<h2 id="_description">DESCRIPTION</h2>
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<p>The <code>nn_errno()</code> function returns the error number corresponding to the
most recent failed operation by the calling thread.</p>
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<div class="admonitionblock note">
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This function is provided for API
<a href="nng_compat.3compat.html">compatibility</a> with legacy <em>libnanomsg</em>.
Consider using the relevant <a href="libnng.3.html">modern API</a> instead.
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The error numbers returned from this function may include
errors caused by system functions, which overlap the usual <code>errno</code> variable,
and this function simply returns the value of <code>errno</code>.
However, the values returned may include numeric values that are not
defined by the system, but are unique to <em>libnanomsg</em>, such as <code>EFSM</code>.
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<p>This library implements the following error numbers, in addition to any others
that might be set for <code>errno</code> by the underlying system:</p>
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<h2 id="_return_values">RETURN VALUES</h2>
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<p>This function returns the value of <code>errno</code>.
If no operation has failed, then this will be zero.</p>
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<h2 id="_errors">ERRORS</h2>
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<code>EINTR</code>
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<p>Operation interrupted.</p>
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<code>ENOMEM</code>
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<p>Insufficient memory.</p>
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<code>EINVAL</code>
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<p>Invalid argument.</p>
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<code>EBUSY</code>
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<p>Resource is busy.</p>
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<code>ETIMEDOUT</code>
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<p>Operation timed out.</p>
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<code>ECONNREFUSED</code>
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<p>Connection refused by peer.</p>
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<code>EBADF</code>
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<p>Invalid or closed socket.</p>
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<code>EAGAIN</code>
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<p>Operation would block.</p>
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<code>ENOTSUP</code>
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<p>Protocol or option not supported.</p>
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<code>EADDRINUSE</code>
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<p>Requested address is already in use.</p>
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<code>EFSM</code>
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<p>Protocol state incorrect.</p>
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<code>EPROTO</code>
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<p>Protocol error.</p>
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<code>EHOSTUNREACH</code>
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<p>Remote peer is unreachable.</p>
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<code>EADDRNOTAVAIL</code>
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<p>Requested address is not available.</p>
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<code>EACCES</code>
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<p>Permission denied.</p>
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<code>EMSGSIZE</code>
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<p>Message is too large.</p>
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<code>ECONNABORTED</code>
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<p>Connection attempt aborted.</p>
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<code>ECONNRESET</code>
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<p>Connection reset by peer.</p>
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<code>EEXIST</code>
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<p>Resource already exists.</p>
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<code>EMFILE</code>
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<p>Too many open files.</p>
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<code>ENOSPC</code>
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<p>Insufficient persistent storage.</p>
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<h2 id="_see_also">SEE ALSO</h2>
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<div class="paragraph text-left">
<p><a href="nn_strerror.3compat.html">nn_strerror(3compat)</a>,
<a href="nng_compat.3compat.html">nng_compat(3compat)</a>,
<a href="nng.7.html">nng(7)</a></p>
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