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| <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" |
| "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> |
| <!-- SPDX-License-Identifier: LGPL-2.1+ --> |
| |
| <refentry id="udevadm" |
| xmlns:xi="http://www.w3.org/2001/XInclude"> |
| |
| <refentryinfo> |
| <title>udevadm</title> |
| <productname>systemd</productname> |
| </refentryinfo> |
| |
| <refmeta> |
| <refentrytitle>udevadm</refentrytitle> |
| <manvolnum>8</manvolnum> |
| </refmeta> |
| |
| <refnamediv> |
| <refname>udevadm</refname><refpurpose>udev management tool</refpurpose> |
| </refnamediv> |
| |
| <refsynopsisdiv> |
| <cmdsynopsis> |
| <command>udevadm</command> |
| <arg><option>--debug</option></arg> |
| <arg><option>--version</option></arg> |
| <arg><option>--help</option></arg> |
| </cmdsynopsis> |
| <cmdsynopsis> |
| <command>udevadm info <optional>options</optional> <optional>devpath</optional></command> |
| </cmdsynopsis> |
| <cmdsynopsis> |
| <command>udevadm trigger <optional>options</optional> <optional>devpath</optional></command> |
| </cmdsynopsis> |
| <cmdsynopsis> |
| <command>udevadm settle <optional>options</optional></command> |
| </cmdsynopsis> |
| <cmdsynopsis> |
| <command>udevadm control <replaceable>option</replaceable></command> |
| </cmdsynopsis> |
| <cmdsynopsis> |
| <command>udevadm monitor <optional>options</optional></command> |
| </cmdsynopsis> |
| <cmdsynopsis> |
| <command>udevadm test <optional>options</optional> <replaceable>devpath</replaceable></command> |
| </cmdsynopsis> |
| <cmdsynopsis> |
| <command>udevadm test-builtin <optional>options</optional> <replaceable>command</replaceable> <replaceable>devpath</replaceable></command> |
| </cmdsynopsis> |
| </refsynopsisdiv> |
| |
| <refsect1><title>Description</title> |
| <para><command>udevadm</command> expects a command and command |
| specific options. It controls the runtime behavior of |
| <command>systemd-udevd</command>, requests kernel events, manages |
| the event queue, and provides simple debugging mechanisms.</para> |
| </refsect1> |
| |
| <refsect1><title>Options</title> |
| <variablelist> |
| <varlistentry> |
| <term><option>-d</option></term> |
| <term><option>--debug</option></term> |
| <listitem> |
| <para>Print debug messages to standard error. This option is implied in <command>udevadm test</command> and |
| <command>udevadm test-builtin</command> commands.</para> |
| </listitem> |
| </varlistentry> |
| |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| </variablelist> |
| |
| <refsect2><title>udevadm info |
| <arg choice="opt"><replaceable>options</replaceable></arg> |
| <arg choice="opt" rep="repeat"><replaceable>devpath</replaceable>|<replaceable>file</replaceable>|<replaceable>unit</replaceable></arg> |
| </title> |
| |
| <para>Query the udev database for device information.</para> |
| |
| <para>Positional arguments should be used to specify one or more devices. Each one may be a device name |
| (in which case it must start with <filename>/dev/</filename>), a sys path (in which case it must start |
| with <filename>/sys/</filename>), or a systemd device unit name (in which case it must end with |
| <literal>.device</literal>, see |
| <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>). |
| </para> |
| |
| <variablelist> |
| <varlistentry> |
| <term><option>-q</option></term> |
| <term><option>--query=<replaceable>TYPE</replaceable></option></term> |
| <listitem> |
| <para>Query the database for the specified type of device data. |
| Valid <replaceable>TYPE</replaceable>s are: |
| <constant>name</constant>, <constant>symlink</constant>, |
| <constant>path</constant>, <constant>property</constant>, |
| <constant>all</constant>.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-p</option></term> |
| <term><option>--path=<replaceable>DEVPATH</replaceable></option></term> |
| <listitem> |
| <para>The <filename>/sys</filename> path of the device to query, e.g. |
| <filename><optional>/sys</optional>/class/block/sda</filename>. This option is an alternative to |
| the positional argument with a <filename>/sys/</filename> prefix. <command>udevadm info |
| --path=/class/block/sda</command> is equivalent to <command>udevadm info |
| /sys/class/block/sda</command>.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-n</option></term> |
| <term><option>--name=<replaceable>FILE</replaceable></option></term> |
| <listitem> |
| <para>The name of the device node or a symlink to query, |
| e.g. <filename><optional>/dev</optional>/sda</filename>. This option is an alternative to the |
| positional argument with a <filename>/dev/</filename> prefix. <command>udevadm info |
| --name=sda</command> is equivalent to <command>udevadm info /dev/sda</command>.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-r</option></term> |
| <term><option>--root</option></term> |
| <listitem> |
| <para>Print absolute paths in <command>name</command> or <command>symlink</command> |
| query.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-a</option></term> |
| <term><option>--attribute-walk</option></term> |
| <listitem> |
| <para>Print all sysfs properties of the specified device that can be used |
| in udev rules to match the specified device. It prints all devices |
| along the chain, up to the root of sysfs that can be used in udev rules.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-x</option></term> |
| <term><option>--export</option></term> |
| <listitem> |
| <para>Print output as key/value pairs. Values are enclosed in single quotes. |
| This takes effects only when <option>--query=property</option> or |
| <option>--device-id-of-file=<replaceable>FILE</replaceable></option> is specified.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-P</option></term> |
| <term><option>--export-prefix=<replaceable>NAME</replaceable></option></term> |
| <listitem> |
| <para>Add a prefix to the key name of exported values. |
| This implies <option>--export</option>.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-d</option></term> |
| <term><option>--device-id-of-file=<replaceable>FILE</replaceable></option></term> |
| <listitem> |
| <para>Print major/minor numbers of the underlying device, where the file lives on. |
| If this is specified, all positional arguments are ignored.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-e</option></term> |
| <term><option>--export-db</option></term> |
| <listitem> |
| <para>Export the content of the udev database.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-c</option></term> |
| <term><option>--cleanup-db</option></term> |
| <listitem> |
| <para>Cleanup the udev database.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-w<optional>SECONDS</optional></option></term> |
| <term><option>--wait-for-initialization<optional>=SECONDS</optional></option></term> |
| <listitem> |
| <para>Wait for device to be initialized. If argument <replaceable>SECONDS</replaceable> |
| is not specified, the default is to wait forever.</para> |
| </listitem> |
| </varlistentry> |
| |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| </variablelist> |
| </refsect2> |
| |
| <refsect2><title>udevadm trigger |
| <arg choice="opt"><replaceable>options</replaceable></arg> |
| <arg choice="opt"><replaceable>devpath</replaceable>|<replaceable>file</replaceable>|<replaceable>unit</replaceable></arg> |
| </title> |
| <para>Request device events from the kernel. Primarily used to replay events at system coldplug time.</para> |
| |
| <para>Takes device specifications as positional arguments. See the description of <command>info</command> |
| above.</para> |
| |
| <variablelist> |
| <varlistentry> |
| <term><option>-v</option></term> |
| <term><option>--verbose</option></term> |
| <listitem> |
| <para>Print the list of devices which will be triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-n</option></term> |
| <term><option>--dry-run</option></term> |
| <listitem> |
| <para>Do not actually trigger the event.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-t</option></term> |
| <term><option>--type=<replaceable>TYPE</replaceable></option></term> |
| <listitem> |
| <para>Trigger a specific type of devices. Valid types are: |
| <command>devices</command>, <command>subsystems</command>. |
| The default value is <command>devices</command>.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-c</option></term> |
| <term><option>--action=<replaceable>ACTION</replaceable></option></term> |
| <listitem> |
| <para>Type of event to be triggered. Possible actions are <literal>add</literal>, |
| <literal>remove</literal>, <literal>change</literal>, <literal>move</literal>, |
| <literal>online</literal>, <literal>offline</literal>, <literal>bind</literal>, |
| and <literal>unbind</literal>. Also, the special value <literal>help</literal> can be used |
| to list the possible actions. The default value is <literal>change</literal>. |
| </para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-s</option></term> |
| <term><option>--subsystem-match=<replaceable>SUBSYSTEM</replaceable></option></term> |
| <listitem> |
| <para>Trigger events for devices which belong to a |
| matching subsystem. This option supports shell style pattern matching. |
| When this option is specified more than once, then each matching result is ORed, that is, |
| all the devices in each subsystem are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-S</option></term> |
| <term><option>--subsystem-nomatch=<replaceable>SUBSYSTEM</replaceable></option></term> |
| <listitem> |
| <para>Do not trigger events for devices which belong to a matching subsystem. This option |
| supports shell style pattern matching. When this option is specified more than once, |
| then each matching result is ANDed, that is, devices which do not match all specified |
| subsystems are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-a</option></term> |
| <term><option>--attr-match=<replaceable>ATTRIBUTE</replaceable>=<replaceable>VALUE</replaceable></option></term> |
| <listitem> |
| <para>Trigger events for devices with a matching sysfs attribute. If a value is specified along |
| with the attribute name, the content of the attribute is matched against the given value using |
| shell style pattern matching. If no value is specified, the existence of the sysfs attribute is |
| checked. When this option is specified multiple times, then each matching result is ANDed, |
| that is, only devices which have all specified attributes are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-A</option></term> |
| <term><option>--attr-nomatch=<replaceable>ATTRIBUTE</replaceable>=<replaceable>VALUE</replaceable></option></term> |
| <listitem> |
| <para>Do not trigger events for devices with a matching sysfs attribute. If a value is specified |
| along with the attribute name, the content of the attribute is matched against the given value |
| using shell style pattern matching. If no value is specified, the existence of the sysfs attribute |
| is checked. When this option is specified multiple times, then each matching result is ANDed, |
| that is, only devices which have none of the specified attributes are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-p</option></term> |
| <term><option>--property-match=<replaceable>PROPERTY</replaceable>=<replaceable>VALUE</replaceable></option></term> |
| <listitem> |
| <para>Trigger events for devices with a matching property value. This option supports shell style |
| pattern matching. When this option is specified more than once, then each matching result is ORed, |
| that is, devices which have one of the specified properties are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-g</option></term> |
| <term><option>--tag-match=<replaceable>PROPERTY</replaceable></option></term> |
| <listitem> |
| <para>Trigger events for devices with a matching tag. When this option is specified multiple times, |
| then each matching result is ANDed, that is, devices which have all specified tags are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-y</option></term> |
| <term><option>--sysname-match=<replaceable>NAME</replaceable></option></term> |
| <listitem> |
| <para>Trigger events for devices for which the last component (i.e. the filename) of the |
| <filename>/sys</filename> path matches the specified <replaceable>PATH</replaceable>. This option |
| supports shell style pattern matching. When this option is specified more than once, then each |
| matching result is ORed, that is, all devices which have any of the specified |
| <replaceable>NAME</replaceable> are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>--name-match=<replaceable>NAME</replaceable></option></term> |
| <listitem> |
| <para>Trigger events for devices with a matching device path. When this option is specified more than once, |
| then each matching result is ORed, that is, all specified devices are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-b</option></term> |
| <term><option>--parent-match=<replaceable>SYSPATH</replaceable></option></term> |
| <listitem> |
| <para>Trigger events for all children of a given device. When this option is specified more than once, |
| then each matching result is ORed, that is, all children of each specified device are triggered.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-w</option></term> |
| <term><option>--settle</option></term> |
| <listitem> |
| <para>Apart from triggering events, also waits for those events to |
| finish. Note that this is different from calling <command>udevadm |
| settle</command>. <command>udevadm settle</command> waits for all |
| events to finish. This option only waits for events triggered by |
| the same command to finish.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>--wait-daemon[=<replaceable>SECONDS</replaceable>]</option></term> |
| <listitem> |
| <para>Before triggering uevents, wait for systemd-udevd daemon to be initialized. |
| Optionally takes timeout value. Default timeout is 5 seconds. This is equivalent to invoke |
| invoking <command>udevadm control --ping</command> before <command>udevadm trigger</command>.</para> |
| </listitem> |
| </varlistentry> |
| |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| </variablelist> |
| |
| <para>In addition, optional positional arguments can be used |
| to specify device names or sys paths. They must start with |
| <filename>/dev</filename> or <filename>/sys</filename> |
| respectively.</para> |
| </refsect2> |
| |
| <refsect2><title>udevadm settle |
| <arg choice="opt"><replaceable>options</replaceable></arg> |
| </title> |
| <para>Watches the udev event queue, and exits if all current events are handled.</para> |
| <variablelist> |
| <varlistentry> |
| <term><option>-t</option></term> |
| <term><option>--timeout=<replaceable>SECONDS</replaceable></option></term> |
| <listitem> |
| <para>Maximum number of seconds to wait for the event |
| queue to become empty. The default value is 120 seconds. A |
| value of 0 will check if the queue is empty and always |
| return immediately.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-E</option></term> |
| <term><option>--exit-if-exists=<replaceable>FILE</replaceable></option></term> |
| <listitem> |
| <para>Stop waiting if file exists.</para> |
| </listitem> |
| </varlistentry> |
| |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| </variablelist> |
| |
| <para>See |
| <citerefentry><refentrytitle>systemd-udev-settle.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> |
| for more information.</para> |
| </refsect2> |
| |
| <refsect2><title>udevadm control <replaceable>option</replaceable></title> |
| <para>Modify the internal state of the running udev daemon.</para> |
| <variablelist> |
| <varlistentry> |
| <term><option>-e</option></term> |
| <term><option>--exit</option></term> |
| <listitem> |
| <para>Signal and wait for systemd-udevd to exit. No option except for |
| <option>--timeout</option> can be specified after this option. |
| Note that <filename>systemd-udevd.service</filename> contains |
| <option>Restart=always</option> and so as a result, this option restarts systemd-udevd. |
| If you want to stop <filename>systemd-udevd.service</filename>, please use the following: |
| <programlisting>systemctl stop systemd-udevd-control.socket systemd-udevd-kernel.socket systemd-udevd.service</programlisting> |
| </para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-l</option></term> |
| <term><option>--log-priority=<replaceable>value</replaceable></option></term> |
| <listitem> |
| <para>Set the internal log level of |
| <filename>systemd-udevd</filename>. Valid values are the |
| numerical syslog priorities or their textual |
| representations: <option>emerg</option>, |
| <option>alert</option>, <option>crit</option>, |
| <option>err</option>, <option>warning</option>, |
| <option>notice</option>, <option>info</option>, and |
| <option>debug</option>.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-s</option></term> |
| <term><option>--stop-exec-queue</option></term> |
| <listitem> |
| <para>Signal systemd-udevd to stop executing new events. Incoming events |
| will be queued.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-S</option></term> |
| <term><option>--start-exec-queue</option></term> |
| <listitem> |
| <para>Signal systemd-udevd to enable the execution of events.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-R</option></term> |
| <term><option>--reload</option></term> |
| <listitem> |
| <para>Signal systemd-udevd to reload the rules files and other databases like the kernel |
| module index. Reloading rules and databases does not apply any changes to already |
| existing devices; the new configuration will only be applied to new events.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-p</option></term> |
| <term><option>--property=<replaceable>KEY</replaceable>=<replaceable>value</replaceable></option></term> |
| <listitem> |
| <para>Set a global property for all events.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-m</option></term> |
| <term><option>--children-max=</option><replaceable>value</replaceable></term> |
| <listitem> |
| <para>Set the maximum number of events, systemd-udevd will handle at the |
| same time.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>--ping</option></term> |
| <listitem> |
| <para>Send a ping message to systemd-udevd and wait for the reply. This may be useful to check that |
| systemd-udevd daemon is running.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-t</option></term> |
| <term><option>--timeout=</option><replaceable>seconds</replaceable></term> |
| <listitem> |
| <para>The maximum number of seconds to wait for a reply from systemd-udevd.</para> |
| </listitem> |
| </varlistentry> |
| |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| </variablelist> |
| </refsect2> |
| |
| <refsect2><title>udevadm monitor |
| <arg choice="opt"><replaceable>options</replaceable></arg> |
| </title> |
| <para>Listens to the kernel uevents and events sent out by a udev rule |
| and prints the devpath of the event to the console. It can be used to analyze the |
| event timing, by comparing the timestamps of the kernel uevent and the udev event. |
| </para> |
| <variablelist> |
| <varlistentry> |
| <term><option>-k</option></term> |
| <term><option>--kernel</option></term> |
| <listitem> |
| <para>Print the kernel uevents.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-u</option></term> |
| <term><option>--udev</option></term> |
| <listitem> |
| <para>Print the udev event after the rule processing.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-p</option></term> |
| <term><option>--property</option></term> |
| <listitem> |
| <para>Also print the properties of the event.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-s</option></term> |
| <term><option>--subsystem-match=<replaceable>string[/string]</replaceable></option></term> |
| <listitem> |
| <para>Filter kernel uevents and udev events by subsystem[/devtype]. Only events with a matching subsystem value will pass. |
| When this option is specified more than once, then each matching result is ORed, that is, all devices in the specified |
| subsystems are monitored.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-t</option></term> |
| <term><option>--tag-match=<replaceable>string</replaceable></option></term> |
| <listitem> |
| <para>Filter udev events by tag. Only udev events with a given tag attached will pass. |
| When this option is specified more than once, then each matching result is ORed, that is, devices which have one of the |
| specified tags are monitored.</para> |
| </listitem> |
| </varlistentry> |
| |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| </variablelist> |
| </refsect2> |
| |
| <refsect2><title>udevadm test |
| <arg choice="opt"><replaceable>options</replaceable></arg> |
| <arg><replaceable>devpath</replaceable></arg> |
| </title> |
| <para>Simulate a udev event run for the given device, and print debug output.</para> |
| <variablelist> |
| <varlistentry> |
| <term><option>-a</option></term> |
| <term><option>--action=<replaceable>ACTION</replaceable></option></term> |
| <listitem> |
| <para>The action string. The special value <literal>help</literal> may be used to list |
| known values.</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><option>-N</option></term> |
| <term><option>--resolve-names=<constant>early</constant>|<constant>late</constant>|<constant>never</constant></option></term> |
| <listitem> |
| <para>Specify when udevadm should resolve names of users |
| and groups. When set to <constant>early</constant> (the |
| default), names will be resolved when the rules are |
| parsed. When set to <constant>late</constant>, names will |
| be resolved for every event. When set to |
| <constant>never</constant>, names will never be resolved |
| and all devices will be owned by root.</para> |
| </listitem> |
| </varlistentry> |
| |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| </variablelist> |
| </refsect2> |
| |
| <refsect2><title>udevadm test-builtin |
| <arg choice="opt"><replaceable>options</replaceable></arg> |
| <arg><replaceable>command</replaceable></arg> |
| <arg><replaceable>devpath</replaceable></arg> |
| </title> |
| <para>Run a built-in command <replaceable>COMMAND</replaceable> |
| for device <replaceable>DEVPATH</replaceable>, and print debug |
| output.</para> |
| <variablelist> |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| </variablelist> |
| </refsect2> |
| </refsect1> |
| |
| <refsect1> |
| <title>See Also</title> |
| <para><citerefentry> |
| <refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum> |
| </citerefentry>, |
| <citerefentry> |
| <refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum> |
| </citerefentry></para> |
| </refsect1> |
| </refentry> |