man/udevadm.xml

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   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
   5 <refentry id="udevadm">
   6   <refentryinfo>
   7     <title>udevadm</title>
   8     <productname>systemd</productname>
   9     <authorgroup>
  10       <author>
  11         <contrib>Developer</contrib>
  12         <firstname>Kay</firstname>
  13         <surname>Sievers</surname>
  14         <email>kay@vrfy.org</email>
  15       </author>
  16     </authorgroup>
  17   </refentryinfo>
  18
  19   <refmeta>
  20     <refentrytitle>udevadm</refentrytitle>
  21     <manvolnum>8</manvolnum>
  22   </refmeta>
  23
  24   <refnamediv>
  25     <refname>udevadm</refname><refpurpose>udev management tool</refpurpose>
  26   </refnamediv>
  27
  28   <refsynopsisdiv>
  29     <cmdsynopsis>
  30       <command>udevadm</command>
  31         <arg><option>--debug</option></arg>
  32         <arg><option>--version</option></arg>
  33         <arg><option>--help</option></arg>
  34     </cmdsynopsis>
  35     <cmdsynopsis>
  36       <command>udevadm info <replaceable>options</replaceable></command>
  37     </cmdsynopsis>
  38     <cmdsynopsis>
  39       <command>udevadm trigger <optional>options</optional></command>
  40     </cmdsynopsis>
  41     <cmdsynopsis>
  42       <command>udevadm settle <optional>options</optional></command>
  43     </cmdsynopsis>
  44     <cmdsynopsis>
  45       <command>udevadm control <replaceable>command</replaceable></command>
  46     </cmdsynopsis>
  47     <cmdsynopsis>
  48       <command>udevadm monitor <optional>options</optional></command>
  49     </cmdsynopsis>
  50     <cmdsynopsis>
  51       <command>udevadm test <optional>options</optional> <replaceable>devpath</replaceable></command>
  52     </cmdsynopsis>
  53     <cmdsynopsis>
  54       <command>udevadm test-builtin <optional>options</optional> <replaceable>command</replaceable> <replaceable>devpath</replaceable></command>
  55     </cmdsynopsis>
  56   </refsynopsisdiv>
  57
  58   <refsect1><title>Description</title>
  59     <para><command>udevadm</command> expects a command and command
  60     specific options.  It controls the runtime behavior of
  61     <command>systemd-udevd</command>, requests kernel events, manages
  62     the event queue, and provides simple debugging mechanisms.</para>
  63   </refsect1>
  64
  65   <refsect1><title>Options</title>
  66     <variablelist>
  67       <varlistentry>
  68         <term><option>--debug</option></term>
  69         <listitem>
  70           <para>Print debug messages to standard error.</para>
  71         </listitem>
  72       </varlistentry>
  73       <varlistentry>
  74         <term><option>--version</option></term>
  75         <listitem>
  76           <para>Print version number.</para>
  77         </listitem>
  78       </varlistentry>
  79       <varlistentry>
  80         <term><option>-h</option></term>
  81         <term><option>--help</option></term>
  82         <listitem>
  83           <para>Print help text.</para>
  84         </listitem>
  85       </varlistentry>
  86     </variablelist>
  87
  88     <refsect2><title>udevadm info
  89       <arg choice="opt"><replaceable>options</replaceable></arg>
  90       <arg choice="opt"><replaceable>devpath</replaceable>|<replaceable>file</replaceable></arg>
  91     </title>
  92
  93       <para>Queries the udev database for device information
  94       stored in the udev database. It can also query the properties
  95       of a device from its sysfs representation to help creating udev
  96       rules that match this device.</para>
  97       <variablelist>
  98         <varlistentry>
  99           <term><option>-q</option></term>
 100           <term><option>--query=<replaceable>TYPE</replaceable></option></term>
 101           <listitem>
 102             <para>Query the database for the specified type of device
 103             data. It needs the <option>--path</option> or
 104             <option>--name</option> to identify the specified device.
 105             Valid <replaceable>TYPE</replaceable>s are:
 106             <constant>name</constant>, <constant>symlink</constant>,
 107             <constant>path</constant>, <constant>property</constant>,
 108             <constant>all</constant>.</para>
 109           </listitem>
 110         </varlistentry>
 111         <varlistentry>
 112           <term><option>-p</option></term>
 113           <term><option>--path=<replaceable>DEVPATH</replaceable></option></term>
 114           <listitem>
 115             <para>The <filename>/sys</filename> path of the device to
 116             query, e.g.
 117             <filename><optional>/sys</optional>/class/block/sda</filename>.
 118             Note that this option usually is not very useful, since
 119             <command>udev</command> can guess the type of the
 120             argument, so <command>udevadm
 121             --devpath=/class/block/sda</command> is equivalent to
 122             <command>udevadm /sys/class/block/sda</command>.</para>
 123           </listitem>
 124         </varlistentry>
 125         <varlistentry>
 126           <term><option>-n</option></term>
 127           <term><option>--name=<replaceable>FILE</replaceable></option></term>
 128           <listitem>
 129             <para>The name of the device node or a symlink to query,
 130             e.g. <filename><optional>/dev</optional>/sda</filename>.
 131             Note that this option usually is not very useful, since
 132             <command>udev</command> can guess the type of the
 133             argument, so <command>udevadm --name=sda</command> is
 134             equivalent to <command>udevadm /dev/sda</command>.</para>
 135           </listitem>
 136         </varlistentry>
 137         <varlistentry>
 138           <term><option>-r</option></term>
 139           <term><option>--root</option></term>
 140           <listitem>
 141             <para>Print absolute paths in <command>name</command> or <command>symlink</command>
 142             query.</para>
 143           </listitem>
 144         </varlistentry>
 145         <varlistentry>
 146           <term><option>-a</option></term>
 147           <term><option>--attribute-walk</option></term>
 148           <listitem>
 149             <para>Print all sysfs properties of the specified device that can be used
 150             in udev rules to match the specified device. It prints all devices
 151             along the chain, up to the root of sysfs that can be used in udev rules.</para>
 152           </listitem>
 153         </varlistentry>
 154         <varlistentry>
 155           <term><option>-x</option></term>
 156           <term><option>--export</option></term>
 157           <listitem>
 158             <para>Print output as key/value pairs. Values are enclosed in single quotes.</para>
 159           </listitem>
 160         </varlistentry>
 161         <varlistentry>
 162           <term><option>-P</option></term>
 163           <term><option>--export-prefix=<replaceable>NAME</replaceable></option></term>
 164           <listitem>
 165             <para>Add a prefix to the key name of exported values.</para>
 166           </listitem>
 167         </varlistentry>
 168         <varlistentry>
 169           <term><option>-d</option></term>
 170           <term><option>--device-id-of-file=<replaceable>FILE</replaceable></option></term>
 171           <listitem>
 172             <para>Print major/minor numbers of the underlying device, where the file
 173             lives on.</para>
 174           </listitem>
 175         </varlistentry>
 176         <varlistentry>
 177           <term><option>-e</option></term>
 178           <term><option>--export-db</option></term>
 179           <listitem>
 180             <para>Export the content of the udev database.</para>
 181           </listitem>
 182         </varlistentry>
 183         <varlistentry>
 184           <term><option>-c</option></term>
 185           <term><option>--cleanup-db</option></term>
 186           <listitem>
 187             <para>Cleanup the udev database.</para>
 188           </listitem>
 189         </varlistentry>
 190         <varlistentry>
 191           <term><option>--version</option></term>
 192           <listitem>
 193             <para>Print version.</para>
 194           </listitem>
 195         </varlistentry>
 196         <varlistentry>
 197           <term><option>-h</option></term>
 198           <term><option>--help</option></term>
 199           <listitem>
 200             <para>Print help text.</para>
 201           </listitem>
 202         </varlistentry>
 203       </variablelist>
 204
 205       <para>In addition, an optional positional argument can be used
 206       to specify a device name or a sys path. It must start with
 207       <filename>/dev</filename> or <filename>/sys</filename>
 208       respectively.</para>
 209     </refsect2>
 210
 211     <refsect2><title>udevadm trigger
 212       <arg choice="opt"><replaceable>options</replaceable></arg>
 213       <arg choice="opt" rep="repeat"><replaceable>devpath</replaceable>|<replaceable>file</replaceable></arg></title>
 214       <para>Request device events from the kernel. Primarily used to replay events at system coldplug time.</para>
 215       <variablelist>
 216         <varlistentry>
 217           <term><option>-v</option></term>
 218           <term><option>--verbose</option></term>
 219           <listitem>
 220             <para>Print the list of devices which will be triggered.</para>
 221           </listitem>
 222         </varlistentry>
 223         <varlistentry>
 224           <term><option>-n</option></term>
 225           <term><option>--dry-run</option></term>
 226           <listitem>
 227             <para>Do not actually trigger the event.</para>
 228           </listitem>
 229         </varlistentry>
 230         <varlistentry>
 231           <term><option>-t</option></term>
 232           <term><option>--type=<replaceable>TYPE</replaceable></option></term>
 233           <listitem>
 234             <para>Trigger a specific type of devices. Valid types are:
 235             <command>devices</command>, <command>subsystems</command>.
 236             The default value is <command>devices</command>.</para>
 237           </listitem>
 238         </varlistentry>
 239         <varlistentry>
 240           <term><option>-c</option></term>
 241           <term><option>--action=<replaceable>ACTION</replaceable></option></term>
 242           <listitem>
 243             <para>Type of event to be triggered. The default value is
 244             <command>change</command>.</para>
 245           </listitem>
 246         </varlistentry>
 247         <varlistentry>
 248           <term><option>-s</option></term>
 249           <term><option>--subsystem-match=<replaceable>SUBSYSTEM</replaceable></option></term>
 250           <listitem>
 251             <para>Trigger events for devices which belong to a
 252             matching subsystem. This option can be specified multiple
 253             times and supports shell style pattern matching.</para>
 254           </listitem>
 255         </varlistentry>
 256         <varlistentry>
 257           <term><option>-S</option></term>
 258           <term><option>--subsystem-nomatch=<replaceable>SUBSYSTEM</replaceable></option></term>
 259           <listitem>
 260             <para>Do not trigger events for devices which belong to a matching subsystem. This option
 261             can be specified multiple times and supports shell style pattern matching.</para>
 262           </listitem>
 263         </varlistentry>
 264         <varlistentry>
 265           <term><option>-a</option></term>
 266           <term><option>--attr-match=<replaceable>ATTRIBUTE</replaceable>=<replaceable>VALUE</replaceable></option></term>
 267           <listitem>
 268             <para>Trigger events for devices with a matching sysfs
 269             attribute. If a value is specified along with the
 270             attribute name, the content of the attribute is matched
 271             against the given value using shell style pattern
 272             matching. If no value is specified, the existence of the
 273             sysfs attribute is checked. This option can be specified
 274             multiple times.</para>
 275           </listitem>
 276         </varlistentry>
 277         <varlistentry>
 278           <term><option>-A</option></term>
 279           <term><option>--attr-nomatch=<replaceable>ATTRIBUTE</replaceable>=<replaceable>VALUE</replaceable></option></term>
 280           <listitem>
 281             <para>Do not trigger events for devices with a matching
 282             sysfs attribute. If a value is specified along with the
 283             attribute name, the content of the attribute is matched
 284             against the given value using shell style pattern
 285             matching. If no value is specified, the existence of the
 286             sysfs attribute is checked. This option can be specified
 287             multiple times.</para>
 288           </listitem>
 289         </varlistentry>
 290         <varlistentry>
 291           <term><option>-p</option></term>
 292           <term><option>--property-match=<replaceable>PROPERTY</replaceable>=<replaceable>VALUE</replaceable></option></term>
 293           <listitem>
 294             <para>Trigger events for devices with a matching property
 295             value. This option can be specified multiple times and
 296             supports shell style pattern matching.</para>
 297           </listitem>
 298         </varlistentry>
 299         <varlistentry>
 300           <term><option>-g</option></term>
 301           <term><option>--tag-match=<replaceable>PROPERTY</replaceable></option></term>
 302           <listitem>
 303             <para>Trigger events for devices with a matching tag. This
 304             option can be specified multiple times.</para>
 305           </listitem>
 306         </varlistentry>
 307         <varlistentry>
 308           <term><option>-y</option></term>
 309           <term><option>--sysname-match=<replaceable>PATH</replaceable></option></term>
 310           <listitem>
 311             <para>Trigger events for devices with a matching sys
 312             device path. This option can be specified multiple times
 313             and supports shell style pattern matching.</para>
 314           </listitem>
 315         </varlistentry>
 316         <varlistentry>
 317           <term><option>--name-match=<replaceable>NAME</replaceable></option></term>
 318           <listitem>
 319             <para>Trigger events for devices with a matching
 320             device path. This option can be specified multiple
 321             times.</para>
 322           </listitem>
 323         </varlistentry>
 324         <varlistentry>
 325           <term><option>-b</option></term>
 326           <term><option>--parent-match=<replaceable>SYSPATH</replaceable></option></term>
 327           <listitem>
 328             <para>Trigger events for all children of a given
 329             device.</para>
 330           </listitem>
 331         </varlistentry>
 332         <varlistentry>
 333           <term><option>-h</option></term>
 334           <term><option>--help</option></term>
 335           <listitem>
 336             <para>Print help text.</para>
 337           </listitem>
 338         </varlistentry>
 339       </variablelist>
 340
 341       <para>In addition, optional positional arguments can be used
 342       to specify device names or sys paths. They must start with
 343       <filename>/dev</filename> or <filename>/sys</filename>
 344       respectively.</para>
 345     </refsect2>
 346
 347     <refsect2><title>udevadm settle
 348       <arg choice="opt"><replaceable>options</replaceable></arg>
 349     </title>
 350       <para>Watches the udev event queue, and exits if all current events are handled.</para>
 351       <variablelist>
 352         <varlistentry>
 353           <term><option>-t</option></term>
 354           <term><option>--timeout=<replaceable>SECONDS</replaceable></option></term>
 355           <listitem>
 356             <para>Maximum number of seconds to wait for the event
 357             queue to become empty. The default value is 120 seconds. A
 358             value of 0 will check if the queue is empty and always
 359             return immediately.</para>
 360           </listitem>
 361         </varlistentry>
 362         <varlistentry>
 363           <term><option>-E</option></term>
 364           <term><option>--exit-if-exists=<replaceable>FILE</replaceable></option></term>
 365           <listitem>
 366             <para>Stop waiting if file exists.</para>
 367           </listitem>
 368         </varlistentry>
 369         <varlistentry>
 370           <term><option>-h</option></term>
 371           <term><option>--help</option></term>
 372           <listitem>
 373             <para>Print help text.</para>
 374           </listitem>
 375         </varlistentry>
 376       </variablelist>
 377     </refsect2>
 378
 379     <refsect2><title>udevadm control <replaceable>command</replaceable></title>
 380       <para>Modify the internal state of the running udev daemon.</para>
 381       <variablelist>
 382         <varlistentry>
 383           <term><option>-x</option></term>
 384           <term><option>--exit</option></term>
 385           <listitem>
 386             <para>Signal and wait for systemd-udevd to exit.</para>
 387           </listitem>
 388         </varlistentry>
 389         <varlistentry>
 390           <term><option>-l</option></term>
 391           <term><option>--log-priority=<replaceable>value</replaceable></option></term>
 392           <listitem>
 393             <para>Set the internal log level of
 394             <filename>systemd-udevd</filename>. Valid values are the
 395             numerical syslog priorities or their textual
 396             representations: <option>emerg</option>,
 397             <option>alert</option>, <option>crit</option>,
 398             <option>err</option>, <option>warning</option>,
 399             <option>notice</option>, <option>info</option>, and
 400             <option>debug</option>.</para>
 401           </listitem>
 402         </varlistentry>
 403         <varlistentry>
 404           <term><option>-s</option></term>
 405           <term><option>--stop-exec-queue</option></term>
 406           <listitem>
 407             <para>Signal systemd-udevd to stop executing new events. Incoming events
 408             will be queued.</para>
 409           </listitem>
 410         </varlistentry>
 411         <varlistentry>
 412           <term><option>-S</option></term>
 413           <term><option>--start-exec-queue</option></term>
 414           <listitem>
 415             <para>Signal systemd-udevd to enable the execution of events.</para>
 416           </listitem>
 417         </varlistentry>
 418         <varlistentry>
 419           <term><option>-R</option></term>
 420           <term><option>--reload</option></term>
 421           <listitem>
 422             <para>Signal systemd-udevd to reload the rules files and other databases like the kernel
 423             module index. Reloading rules and databases does not apply any changes to already
 424             existing devices; the new configuration will only be applied to new events.</para>
 425           </listitem>
 426         </varlistentry>
 427         <varlistentry>
 428           <term><option>-p</option></term>
 429           <term><option>--property=<replaceable>KEY</replaceable>=<replaceable>value</replaceable></option></term>
 430           <listitem>
 431             <para>Set a global property for all events.</para>
 432           </listitem>
 433         </varlistentry>
 434         <varlistentry>
 435           <term><option>-m</option></term>
 436           <term><option>--children-max=</option><replaceable>value</replaceable></term>
 437           <listitem>
 438             <para>Set the maximum number of events, systemd-udevd will handle at the
 439             same time.</para>
 440           </listitem>
 441         </varlistentry>
 442         <varlistentry>
 443           <term><option>--timeout=</option><replaceable>seconds</replaceable></term>
 444           <listitem>
 445             <para>The maximum number of seconds to wait for a reply from systemd-udevd.</para>
 446           </listitem>
 447         </varlistentry>
 448         <varlistentry>
 449           <term><option>-h</option></term>
 450           <term><option>--help</option></term>
 451           <listitem>
 452             <para>Print help text.</para>
 453           </listitem>
 454         </varlistentry>
 455       </variablelist>
 456     </refsect2>
 457
 458     <refsect2><title>udevadm monitor
 459       <arg choice="opt"><replaceable>options</replaceable></arg>
 460     </title>
 461       <para>Listens to the kernel uevents and events sent out by a udev rule
 462       and prints the devpath of the event to the console. It can be used to analyze the
 463       event timing, by comparing the timestamps of the kernel uevent and the udev event.
 464       </para>
 465       <variablelist>
 466         <varlistentry>
 467           <term><option>-k</option></term>
 468           <term><option>--kernel</option></term>
 469           <listitem>
 470             <para>Print the kernel uevents.</para>
 471           </listitem>
 472         </varlistentry>
 473         <varlistentry>
 474           <term><option>-u</option></term>
 475           <term><option>--udev</option></term>
 476           <listitem>
 477             <para>Print the udev event after the rule processing.</para>
 478           </listitem>
 479         </varlistentry>
 480         <varlistentry>
 481           <term><option>-p</option></term>
 482           <term><option>--property</option></term>
 483           <listitem>
 484             <para>Also print the properties of the event.</para>
 485           </listitem>
 486         </varlistentry>
 487         <varlistentry>
 488           <term><option>-s</option></term>
 489           <term><option>--subsystem-match=<replaceable>string[/string]</replaceable></option></term>
 490           <listitem>
 491             <para>Filter events by subsystem[/devtype]. Only udev events with a matching subsystem value will pass.</para>
 492           </listitem>
 493         </varlistentry>
 494         <varlistentry>
 495           <term><option>-t</option></term>
 496           <term><option>--tag-match=<replaceable>string</replaceable></option></term>
 497           <listitem>
 498             <para>Filter events by property. Only udev events with a given tag attached will pass.</para>
 499           </listitem>
 500         </varlistentry>
 501         <varlistentry>
 502           <term><option>-h</option></term>
 503           <term><option>--help</option></term>
 504           <listitem>
 505             <para>Print help text.</para>
 506           </listitem>
 507         </varlistentry>
 508       </variablelist>
 509     </refsect2>
 510
 511     <refsect2><title>udevadm test
 512       <arg choice="opt"><replaceable>options</replaceable></arg>
 513       <arg><replaceable>devpath</replaceable></arg>
 514     </title>
 515       <para>Simulate a udev event run for the given device, and print debug output.</para>
 516       <variablelist>
 517         <varlistentry>
 518           <term><option>-a</option></term>
 519           <term><option>--action=<replaceable>string</replaceable></option></term>
 520           <listitem>
 521             <para>The action string.</para>
 522           </listitem>
 523         </varlistentry>
 524         <varlistentry>
 525           <term><option>-N</option></term>
 526           <term><option>--resolve-names=<constant>early</constant>|<constant>late</constant>|<constant>never</constant></option></term>
 527           <listitem>
 528             <para>Specify when udevadm should resolve names of users
 529             and groups.  When set to <constant>early</constant> (the
 530             default), names will be resolved when the rules are
 531             parsed. When set to <constant>late</constant>, names will
 532             be resolved for every event. When set to
 533             <constant>never</constant>, names will never be resolved
 534             and all devices will be owned by root.</para>
 535           </listitem>
 536         </varlistentry>
 537         <varlistentry>
 538           <term><option>-h</option></term>
 539           <term><option>--help</option></term>
 540           <listitem>
 541             <para>Print help text.</para>
 542           </listitem>
 543         </varlistentry>
 544       </variablelist>
 545     </refsect2>
 546
 547     <refsect2><title>udevadm test-builtin
 548       <arg choice="opt"><replaceable>options</replaceable></arg>
 549       <arg><replaceable>command</replaceable></arg>
 550       <arg><replaceable>devpath</replaceable></arg>
 551     </title>
 552       <para>Run a built-in command <replaceable>COMMAND</replaceable>
 553       for device <replaceable>DEVPATH</replaceable>, and print debug
 554       output.</para>
 555       <variablelist>
 556         <varlistentry>
 557           <term><option>-h</option></term>
 558           <term><option>--help</option></term>
 559           <listitem>
 560             <para>Print help text.</para>
 561           </listitem>
 562         </varlistentry>
 563       </variablelist>
 564     </refsect2>
 565   </refsect1>
 566
 567   <refsect1>
 568     <title>See Also</title>
 569     <para><citerefentry>
 570         <refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum>
 571     </citerefentry>,
 572     <citerefentry>
 573         <refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum>
 574     </citerefentry></para>
 575   </refsect1>
 576 </refentry>