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- <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 208</span><hr><div class="refentry"><a name="sd_is_fifo"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_is_fifo, sd_is_socket, sd_is_socket_inet, sd_is_socket_unix, sd_is_mq — Check the type of a file descriptor</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><pre class="funcsynopsisinfo">#include <systemd/sd-daemon.h></pre><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_fifo</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">path</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_socket</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">family</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">type</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">listening</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_socket_inet</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">family</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">type</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">listening</var>, </td></tr><tr><td> </td><td>uint16_t <var class="pdparam">port</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_socket_unix</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">type</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">listening</var>, </td></tr><tr><td> </td><td>const char* <var class="pdparam">path</var>, </td></tr><tr><td> </td><td>size_t <var class="pdparam">length</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_mq</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">path</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm274698824000"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><code class="function">sd_is_fifo()</code> may be called
+ <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 217</span><hr><div class="refentry"><a name="sd_is_fifo"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_is_fifo, sd_is_socket, sd_is_socket_inet, sd_is_socket_unix, sd_is_mq, sd_is_special — Check the type of a file descriptor</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><pre class="funcsynopsisinfo">#include <systemd/sd-daemon.h></pre><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_fifo</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">path</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_socket</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">family</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">type</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">listening</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_socket_inet</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">family</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">type</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">listening</var>, </td></tr><tr><td> </td><td>uint16_t <var class="pdparam">port</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_socket_unix</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">type</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">listening</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">path</var>, </td></tr><tr><td> </td><td>size_t <var class="pdparam">length</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_mq</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">path</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_is_special</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">path</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm214188037616"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><code class="function">sd_is_fifo()</code> may be called
to check whether the specified file descriptor refers
to a FIFO or pipe. If the <em class="parameter"><code>path</code></em>
parameter is not <code class="constant">NULL</code>, it is
a POSIX message queue. If the
<em class="parameter"><code>path</code></em> parameter is not
<code class="constant">NULL</code>, it is checked whether the
- message queue is bound to the specified name.</p></div><div class="refsect1"><a name="idm274698792912"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value">¶</a></h2><p>On failure, these calls return a negative
+ message queue is bound to the specified name.</p><p><code class="function">sd_is_special()</code> may be
+ called to check whether the specified file descriptor
+ refers to a special file. If the
+ <em class="parameter"><code>path</code></em> parameter is not
+ <code class="constant">NULL</code>, it is checked whether the file
+ descriptor is bound to the specified file
+ name. Special files in this context are character
+ device nodes and files in <code class="filename">/proc</code>
+ or <code class="filename">/sys</code>.</p></div><div class="refsect1"><a name="idm214183036656"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value">¶</a></h2><p>On failure, these calls return a negative
errno-style error code. If the file descriptor is of
the specified type and bound to the specified address,
a positive return value is returned, otherwise
- zero.</p></div><div class="refsect1"><a name="idm274698791440"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes">¶</a></h2><p>These functions are provided by the reference
- implementation of APIs for new-style daemons and
- distributed with the systemd package. The algorithms
- they implement are simple, and they can easily be
- reimplemented in daemons if it is important to support
- this interface without using the reference
- implementation.</p><p>Internally, these function use a combination of
+ zero.</p></div><div class="refsect1"><a name="idm214183035216"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes">¶</a></h2><p><a name="pkgconfig-text"></a>These APIs are implemented as a shared
+ library, which can be compiled and linked to with the
+ <code class="constant">libsystemd</code> <a href="http://linux.die.net/man/1/pkg-config"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a>
+ file.</p><p>Internally, these function use a combination of
<code class="filename">fstat()</code> and
<code class="filename">getsockname()</code> to check the file
- descriptor type and where it is bound to.</p><p>For details about the algorithms, check the
- liberally licensed reference implementation sources:
- <a class="ulink" href="http://cgit.freedesktop.org/systemd/systemd/plain/src/libsystemd-daemon/sd-daemon.c" target="_top">http://cgit.freedesktop.org/systemd/systemd/plain/src/libsystemd-daemon/sd-daemon.c</a>
- and <a class="ulink" href="http://cgit.freedesktop.org/systemd/systemd/plain/src/systemd/sd-daemon.h" target="_top">http://cgit.freedesktop.org/systemd/systemd/plain/src/systemd/sd-daemon.h</a></p><p><code class="function">sd_is_fifo()</code> and the
- related functions are implemented in the reference
- implementation's <code class="filename">sd-daemon.c</code> and
- <code class="filename">sd-daemon.h</code> files. These
- interfaces are available as shared library, which can
- be compiled and linked to with the
- <code class="constant">libsystemd-daemon</code> <a href="pkg-config.html"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a>
- file. Alternatively, applications consuming these APIs
- may copy the implementation into their source
- tree. For more details about the reference
- implementation see
- <a href="sd-daemon.html"><span class="citerefentry"><span class="refentrytitle">sd-daemon</span>(3)</span></a>.</p><p>These functions continue to work as described,
- even if -DDISABLE_SYSTEMD is set during
- compilation.</p></div><div class="refsect1"><a name="idm274698781152"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
+ descriptor type and where it is bound to.</p></div><div class="refsect1"><a name="idm214183032080"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
<a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
<a href="sd-daemon.html"><span class="citerefentry"><span class="refentrytitle">sd-daemon</span>(3)</span></a>,
<a href="sd_listen_fds.html"><span class="citerefentry"><span class="refentrytitle">sd_listen_fds</span>(3)</span></a>,