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                  <a href="#libudev-udev-device.description" class="shortcut">Description</a></span>
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<a name="libudev-udev-device"></a><div class="titlepage"></div>
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<h2><span class="refentrytitle"><a name="libudev-udev-device.top_of_page"></a>udev_device</span></h2>
<p>udev_device — kernel sys devices</p>
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<td class="gallery_image" valign="top" align="right"></td>
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<div class="refsect1">
<a name="libudev-udev-device.functions"></a><h2>Functions</h2>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="functions_return">
<col class="functions_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-ref" title="udev_device_ref ()">udev_device_ref</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-unref" title="udev_device_unref ()">udev_device_unref</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev.html#udev" title="struct udev"><span class="returnvalue">udev</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-udev" title="udev_device_get_udev ()">udev_device_get_udev</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-new-from-syspath" title="udev_device_new_from_syspath ()">udev_device_new_from_syspath</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-new-from-devnum" title="udev_device_new_from_devnum ()">udev_device_new_from_devnum</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-new-from-subsystem-sysname" title="udev_device_new_from_subsystem_sysname ()">udev_device_new_from_subsystem_sysname</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-new-from-device-id" title="udev_device_new_from_device_id ()">udev_device_new_from_device_id</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-new-from-environment" title="udev_device_new_from_environment ()">udev_device_new_from_environment</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-parent" title="udev_device_get_parent ()">udev_device_get_parent</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-parent-with-subsystem-devtype" title="udev_device_get_parent_with_subsystem_devtype ()">udev_device_get_parent_with_subsystem_devtype</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-devpath" title="udev_device_get_devpath ()">udev_device_get_devpath</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-subsystem" title="udev_device_get_subsystem ()">udev_device_get_subsystem</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-devtype" title="udev_device_get_devtype ()">udev_device_get_devtype</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-syspath" title="udev_device_get_syspath ()">udev_device_get_syspath</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-sysname" title="udev_device_get_sysname ()">udev_device_get_sysname</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-sysnum" title="udev_device_get_sysnum ()">udev_device_get_sysnum</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-devnode" title="udev_device_get_devnode ()">udev_device_get_devnode</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-is-initialized" title="udev_device_get_is_initialized ()">udev_device_get_is_initialized</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-devlinks-list-entry" title="udev_device_get_devlinks_list_entry ()">udev_device_get_devlinks_list_entry</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-properties-list-entry" title="udev_device_get_properties_list_entry ()">udev_device_get_properties_list_entry</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-tags-list-entry" title="udev_device_get_tags_list_entry ()">udev_device_get_tags_list_entry</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-property-value" title="udev_device_get_property_value ()">udev_device_get_property_value</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-driver" title="udev_device_get_driver ()">udev_device_get_driver</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">dev_t</span>
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-devnum" title="udev_device_get_devnum ()">udev_device_get_devnum</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-action" title="udev_device_get_action ()">udev_device_get_action</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-sysattr-value" title="udev_device_get_sysattr_value ()">udev_device_get_sysattr_value</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-set-sysattr-value" title="udev_device_set_sysattr_value ()">udev_device_set_sysattr_value</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> *
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-sysattr-list-entry" title="udev_device_get_sysattr_list_entry ()">udev_device_get_sysattr_list_entry</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">unsigned long long <span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-seqnum" title="udev_device_get_seqnum ()">udev_device_get_seqnum</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">unsigned long long <span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-get-usec-since-initialized" title="udev_device_get_usec_since_initialized ()">udev_device_get_usec_since_initialized</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libudev-udev-device.html#udev-device-has-tag" title="udev_device_has_tag ()">udev_device_has_tag</a> <span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="libudev-udev-device.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="name">
<col class="description">
</colgroup>
<tbody><tr>
<td class="datatype_keyword">struct</td>
<td class="function_name"><a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device">udev_device</a></td>
</tr></tbody>
</table></div>
</div>
<div class="refsect1">
<a name="libudev-udev-device.description"></a><h2>Description</h2>
<p>Representation of kernel sys devices. Devices are uniquely identified
by their syspath, every device has exactly one path in the kernel sys
filesystem. Devices usually belong to a kernel subsystem, and have
a unique name inside that subsystem.</p>
</div>
<div class="refsect1">
<a name="libudev-udev-device.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="udev-device-ref"></a><h3>udev_device_ref ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_ref (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Take a reference of a udev device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.2.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.2.6"></a><h4>Returns</h4>
<p> the passed udev device</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-unref"></a><h3>udev_device_unref ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_unref (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Drop a reference of a udev device. If the refcount reaches zero,
the resources of the device will be released.</p>
<div class="refsect3">
<a name="id-1.2.4.6.3.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.3.6"></a><h4>Returns</h4>
<p> <span class="type">NULL</span></p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-udev"></a><h3>udev_device_get_udev ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev.html#udev" title="struct udev"><span class="returnvalue">udev</span></a> *
udev_device_get_udev (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the udev library context the device was created with.</p>
<div class="refsect3">
<a name="id-1.2.4.6.4.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.4.6"></a><h4>Returns</h4>
<p> the udev library context</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-new-from-syspath"></a><h3>udev_device_new_from_syspath ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_new_from_syspath (<em class="parameter"><code><span class="type">struct udev</span> *udev</code></em>,
                              <em class="parameter"><code>const <span class="type">char</span> *syspath</code></em>);</pre>
<p>Create new udev device, and fill in information from the sys
device and the udev database entry. The syspath is the absolute
path to the device, including the sys mount point.</p>
<p>The initial refcount is 1, and needs to be decremented to
release the resources of the udev device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.5.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev</p></td>
<td class="parameter_description"><p>udev library context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>syspath</p></td>
<td class="parameter_description"><p>sys device path including sys directory</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.5.7"></a><h4>Returns</h4>
<p> a new udev device, or <span class="type">NULL</span>, if it does not exist</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-new-from-devnum"></a><h3>udev_device_new_from_devnum ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_new_from_devnum (<em class="parameter"><code><span class="type">struct udev</span> *udev</code></em>,
                             <em class="parameter"><code><span class="type">char</span> type</code></em>,
                             <em class="parameter"><code><span class="type">dev_t</span> devnum</code></em>);</pre>
<p>Create new udev device, and fill in information from the sys
device and the udev database entry. The device is looked-up
by its major/minor number and type. Character and block device
numbers are not unique across the two types.</p>
<p>The initial refcount is 1, and needs to be decremented to
release the resources of the udev device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.6.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev</p></td>
<td class="parameter_description"><p>udev library context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>type</p></td>
<td class="parameter_description"><p>char or block device</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>devnum</p></td>
<td class="parameter_description"><p>device major/minor number</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.6.7"></a><h4>Returns</h4>
<p> a new udev device, or <span class="type">NULL</span>, if it does not exist</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-new-from-subsystem-sysname"></a><h3>udev_device_new_from_subsystem_sysname ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_new_from_subsystem_sysname
                               (<em class="parameter"><code><span class="type">struct udev</span> *udev</code></em>,
                                <em class="parameter"><code>const <span class="type">char</span> *subsystem</code></em>,
                                <em class="parameter"><code>const <span class="type">char</span> *sysname</code></em>);</pre>
<p>Create new udev device, and fill in information from the sys device
and the udev database entry. The device is looked up by the subsystem
and name string of the device, like "mem" / "zero", or "block" / "sda".</p>
<p>The initial refcount is 1, and needs to be decremented to
release the resources of the udev device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.7.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev</p></td>
<td class="parameter_description"><p>udev library context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>subsystem</p></td>
<td class="parameter_description"><p>the subsystem of the device</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>sysname</p></td>
<td class="parameter_description"><p>the name of the device</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.7.7"></a><h4>Returns</h4>
<p> a new udev device, or <span class="type">NULL</span>, if it does not exist</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-new-from-device-id"></a><h3>udev_device_new_from_device_id ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_new_from_device_id (<em class="parameter"><code><span class="type">struct udev</span> *udev</code></em>,
                                <em class="parameter"><code>const <span class="type">char</span> *id</code></em>);</pre>
<p>Create new udev device, and fill in information from the sys
device and the udev database entry. The device is looked-up
by a special string:
  b8:2          - block device major:minor
  c128:1        - char device major:minor
  n3            - network device ifindex
  +sound:card29 - kernel driver core subsystem:device name</p>
<p>The initial refcount is 1, and needs to be decremented to
release the resources of the udev device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.8.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev</p></td>
<td class="parameter_description"><p>udev library context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>id</p></td>
<td class="parameter_description"><p>text string identifying a kernel device</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.8.7"></a><h4>Returns</h4>
<p> a new udev device, or <span class="type">NULL</span>, if it does not exist</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-new-from-environment"></a><h3>udev_device_new_from_environment ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_new_from_environment (<em class="parameter"><code><span class="type">struct udev</span> *udev</code></em>);</pre>
<p>Create new udev device, and fill in information from the
current process environment. This only works reliable if
the process is called from a udev rule. It is usually used
for tools executed from IMPORT= rules.</p>
<p>The initial refcount is 1, and needs to be decremented to
release the resources of the udev device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.9.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev</p></td>
<td class="parameter_description"><p>udev library context</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.9.7"></a><h4>Returns</h4>
<p> a new udev device, or <span class="type">NULL</span>, if it does not exist</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-parent"></a><h3>udev_device_get_parent ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_get_parent (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Find the next parent device, and fill in information from the sys
device and the udev database entry.</p>
<p>Returned device is not referenced. It is attached to the child
device, and will be cleaned up when the child device is cleaned up.</p>
<p>It is not necessarily just the upper level directory, empty or not
recognized sys directories are ignored.</p>
<p>It can be called as many times as needed, without caring about
references.</p>
<div class="refsect3">
<a name="id-1.2.4.6.10.8"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>the device to start searching from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.10.9"></a><h4>Returns</h4>
<p> a new udev device, or <span class="type">NULL</span>, if it no parent exist.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-parent-with-subsystem-devtype"></a><h3>udev_device_get_parent_with_subsystem_devtype ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-device.html#udev-device" title="struct udev_device"><span class="returnvalue">udev_device</span></a> *
udev_device_get_parent_with_subsystem_devtype
                               (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>,
                                <em class="parameter"><code>const <span class="type">char</span> *subsystem</code></em>,
                                <em class="parameter"><code>const <span class="type">char</span> *devtype</code></em>);</pre>
<p>Find the next parent device, with a matching subsystem and devtype
value, and fill in information from the sys device and the udev
database entry.</p>
<p>If devtype is <span class="type">NULL</span>, only subsystem is checked, and any devtype will
match.</p>
<p>Returned device is not referenced. It is attached to the child
device, and will be cleaned up when the child device is cleaned up.</p>
<p>It can be called as many times as needed, without caring about
references.</p>
<div class="refsect3">
<a name="id-1.2.4.6.11.8"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device to start searching from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>subsystem</p></td>
<td class="parameter_description"><p>the subsystem of the device</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>devtype</p></td>
<td class="parameter_description"><p>the type (DEVTYPE) of the device</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.11.9"></a><h4>Returns</h4>
<p> a new udev device, or <span class="type">NULL</span> if no matching parent exists.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-devpath"></a><h3>udev_device_get_devpath ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_devpath (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the kernel devpath value of the udev device. The path
does not contain the sys mount point, and starts with a '/'.</p>
<div class="refsect3">
<a name="id-1.2.4.6.12.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.12.6"></a><h4>Returns</h4>
<p> the devpath of the udev device</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-subsystem"></a><h3>udev_device_get_subsystem ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_subsystem (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the subsystem string of the udev device. The string does not
contain any "/".</p>
<div class="refsect3">
<a name="id-1.2.4.6.13.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.13.6"></a><h4>Returns</h4>
<p> the subsystem name of the udev device, or <span class="type">NULL</span> if it can not be determined</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-devtype"></a><h3>udev_device_get_devtype ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_devtype (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the devtype string of the udev device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.14.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.14.6"></a><h4>Returns</h4>
<p> the devtype name of the udev device, or <span class="type">NULL</span> if it can not be determined</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-syspath"></a><h3>udev_device_get_syspath ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_syspath (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the sys path of the udev device. The path is an
absolute path and starts with the sys mount point.</p>
<div class="refsect3">
<a name="id-1.2.4.6.15.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.15.6"></a><h4>Returns</h4>
<p> the sys path of the udev device</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-sysname"></a><h3>udev_device_get_sysname ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_sysname (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Get the kernel device name in /sys.</p>
<div class="refsect3">
<a name="id-1.2.4.6.16.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.16.6"></a><h4>Returns</h4>
<p> the name string of the device device</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-sysnum"></a><h3>udev_device_get_sysnum ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_sysnum (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Get the instance number of the device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.17.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.17.6"></a><h4>Returns</h4>
<p> the trailing number string of the device name</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-devnode"></a><h3>udev_device_get_devnode ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_devnode (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the device node file name belonging to the udev device.
The path is an absolute path, and starts with the device directory.</p>
<div class="refsect3">
<a name="id-1.2.4.6.18.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.18.6"></a><h4>Returns</h4>
<p> the device node file name of the udev device, or <span class="type">NULL</span> if no device node exists</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-is-initialized"></a><h3>udev_device_get_is_initialized ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
udev_device_get_is_initialized (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Check if udev has already handled the device and has set up
device node permissions and context, or has renamed a network
device.</p>
<p>This is only implemented for devices with a device node
or network interfaces. All other devices return 1 here.</p>
<div class="refsect3">
<a name="id-1.2.4.6.19.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.19.7"></a><h4>Returns</h4>
<p> 1 if the device is set up. 0 otherwise.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-devlinks-list-entry"></a><h3>udev_device_get_devlinks_list_entry ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> *
udev_device_get_devlinks_list_entry (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the list of device links pointing to the device file of
the udev device. The next list entry can be retrieved with
<a class="link" href="libudev-udev-list.html#udev-list-entry-get-next" title="udev_list_entry_get_next ()"><code class="function">udev_list_entry_get_next()</code></a>, which returns <span class="type">NULL</span> if no more entries exist.
The devlink path can be retrieved from the list entry by
<a class="link" href="libudev-udev-list.html#udev-list-entry-get-name" title="udev_list_entry_get_name ()"><code class="function">udev_list_entry_get_name()</code></a>. The path is an absolute path, and starts with
the device directory.</p>
<div class="refsect3">
<a name="id-1.2.4.6.20.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.20.6"></a><h4>Returns</h4>
<p> the first entry of the device node link list</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-properties-list-entry"></a><h3>udev_device_get_properties_list_entry ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> *
udev_device_get_properties_list_entry (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the list of key/value device properties of the udev
device. The next list entry can be retrieved with <a class="link" href="libudev-udev-list.html#udev-list-entry-get-next" title="udev_list_entry_get_next ()"><code class="function">udev_list_entry_get_next()</code></a>,
which returns <span class="type">NULL</span> if no more entries exist. The property name
can be retrieved from the list entry by <a class="link" href="libudev-udev-list.html#udev-list-entry-get-name" title="udev_list_entry_get_name ()"><code class="function">udev_list_entry_get_name()</code></a>,
the property value by <a class="link" href="libudev-udev-list.html#udev-list-entry-get-value" title="udev_list_entry_get_value ()"><code class="function">udev_list_entry_get_value()</code></a>.</p>
<div class="refsect3">
<a name="id-1.2.4.6.21.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.21.6"></a><h4>Returns</h4>
<p> the first entry of the property list</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-tags-list-entry"></a><h3>udev_device_get_tags_list_entry ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> *
udev_device_get_tags_list_entry (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the list of tags attached to the udev device. The next
list entry can be retrieved with <a class="link" href="libudev-udev-list.html#udev-list-entry-get-next" title="udev_list_entry_get_next ()"><code class="function">udev_list_entry_get_next()</code></a>,
which returns <span class="type">NULL</span> if no more entries exist. The tag string
can be retrieved from the list entry by <a class="link" href="libudev-udev-list.html#udev-list-entry-get-name" title="udev_list_entry_get_name ()"><code class="function">udev_list_entry_get_name()</code></a>.</p>
<div class="refsect3">
<a name="id-1.2.4.6.22.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.22.6"></a><h4>Returns</h4>
<p> the first entry of the tag list</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-property-value"></a><h3>udev_device_get_property_value ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_property_value (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>,
                                <em class="parameter"><code>const <span class="type">char</span> *key</code></em>);</pre>
<p>Get the value of a given property.</p>
<div class="refsect3">
<a name="id-1.2.4.6.23.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>key</p></td>
<td class="parameter_description"><p>property name</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.23.6"></a><h4>Returns</h4>
<p> the property string, or <span class="type">NULL</span> if there is no such property.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-driver"></a><h3>udev_device_get_driver ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_driver (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Get the kernel driver name.</p>
<div class="refsect3">
<a name="id-1.2.4.6.24.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.24.6"></a><h4>Returns</h4>
<p> the driver name string, or <span class="type">NULL</span> if there is no driver attached.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-devnum"></a><h3>udev_device_get_devnum ()</h3>
<pre class="programlisting"><span class="returnvalue">dev_t</span>
udev_device_get_devnum (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Get the device major/minor number.</p>
<div class="refsect3">
<a name="id-1.2.4.6.25.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.25.6"></a><h4>Returns</h4>
<p> the dev_t number.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-action"></a><h3>udev_device_get_action ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_action (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>This is only valid if the device was received through a monitor. Devices read from
sys do not have an action string. Usual actions are: add, remove, change, online,
offline.</p>
<div class="refsect3">
<a name="id-1.2.4.6.26.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.26.6"></a><h4>Returns</h4>
<p> the kernel action value, or <span class="type">NULL</span> if there is no action value available.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-sysattr-value"></a><h3>udev_device_get_sysattr_value ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
udev_device_get_sysattr_value (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>,
                               <em class="parameter"><code>const <span class="type">char</span> *sysattr</code></em>);</pre>
<p>The retrieved value is cached in the device. Repeated calls will return the same
value and not open the attribute again.</p>
<div class="refsect3">
<a name="id-1.2.4.6.27.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>sysattr</p></td>
<td class="parameter_description"><p>attribute name</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.27.6"></a><h4>Returns</h4>
<p> the content of a sys attribute file, or <span class="type">NULL</span> if there is no sys attribute value.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-set-sysattr-value"></a><h3>udev_device_set_sysattr_value ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
udev_device_set_sysattr_value (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>,
                               <em class="parameter"><code>const <span class="type">char</span> *sysattr</code></em>,
                               <em class="parameter"><code><span class="type">char</span> *value</code></em>);</pre>
<p>Update the contents of the sys attribute and the cached value of the device.</p>
<div class="refsect3">
<a name="id-1.2.4.6.28.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>sysattr</p></td>
<td class="parameter_description"><p>attribute name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>value</p></td>
<td class="parameter_description"><p>new value to be set</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.28.6"></a><h4>Returns</h4>
<p> Negative error code on failure or 0 on success.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-sysattr-list-entry"></a><h3>udev_device_get_sysattr_list_entry ()</h3>
<pre class="programlisting">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> *
udev_device_get_sysattr_list_entry (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Retrieve the list of available sysattrs, with value being empty;
This just return all available sysfs attributes for a particular
device without reading their values.</p>
<div class="refsect3">
<a name="id-1.2.4.6.29.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.29.6"></a><h4>Returns</h4>
<p> the first entry of the property list</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-seqnum"></a><h3>udev_device_get_seqnum ()</h3>
<pre class="programlisting">unsigned long long <span class="returnvalue">int</span>
udev_device_get_seqnum (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>This is only valid if the device was received through a monitor. Devices read from
sys do not have a sequence number.</p>
<div class="refsect3">
<a name="id-1.2.4.6.30.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.30.6"></a><h4>Returns</h4>
<p> the kernel event sequence number, or 0 if there is no sequence number available.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-get-usec-since-initialized"></a><h3>udev_device_get_usec_since_initialized ()</h3>
<pre class="programlisting">unsigned long long <span class="returnvalue">int</span>
udev_device_get_usec_since_initialized
                               (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>);</pre>
<p>Return the number of microseconds passed since udev set up the
device for the first time.</p>
<p>This is only implemented for devices with need to store properties
in the udev database. All other devices return 0 here.</p>
<div class="refsect3">
<a name="id-1.2.4.6.31.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.31.7"></a><h4>Returns</h4>
<p> the number of microseconds since the device was first seen.</p>
<p></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="udev-device-has-tag"></a><h3>udev_device_has_tag ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
udev_device_has_tag (<em class="parameter"><code><span class="type">struct udev_device</span> *udev_device</code></em>,
                     <em class="parameter"><code>const <span class="type">char</span> *tag</code></em>);</pre>
<p>Check if a given device has a certain tag associated.</p>
<div class="refsect3">
<a name="id-1.2.4.6.32.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>udev_device</p></td>
<td class="parameter_description"><p>udev device</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>tag</p></td>
<td class="parameter_description"><p>tag name</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.6.32.6"></a><h4>Returns</h4>
<p> 1 if the tag is found. 0 otherwise.</p>
<p></p>
</div>
</div>
</div>
<div class="refsect1">
<a name="libudev-udev-device.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="udev-device"></a><h3>struct udev_device</h3>
<pre class="programlisting">struct udev_device;</pre>
<p>Opaque object representing one kernel sys device.</p>
</div>
</div>
</div>
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