man/udevadm.xml

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  25
  26 <refentry id="udevadm"
  27           xmlns:xi="http://www.w3.org/2001/XInclude">
  28
  29   <refentryinfo>
  30     <title>udevadm</title>
  31     <productname>systemd</productname>
  32     <authorgroup>
  33       <author>
  34         <contrib>Developer</contrib>
  35         <firstname>Kay</firstname>
  36         <surname>Sievers</surname>
  37         <email>kay@vrfy.org</email>
  38       </author>
  39     </authorgroup>
  40   </refentryinfo>
  41
  42   <refmeta>
  43     <refentrytitle>udevadm</refentrytitle>
  44     <manvolnum>8</manvolnum>
  45   </refmeta>
  46
  47   <refnamediv>
  48     <refname>udevadm</refname><refpurpose>udev management tool</refpurpose>
  49   </refnamediv>
  50
  51   <refsynopsisdiv>
  52     <cmdsynopsis>
  53       <command>udevadm</command>
  54         <arg><option>--debug</option></arg>
  55         <arg><option>--version</option></arg>
  56         <arg><option>--help</option></arg>
  57     </cmdsynopsis>
  58     <cmdsynopsis>
  59       <command>udevadm info <optional>options</optional> <optional>devpath</optional></command>
  60     </cmdsynopsis>
  61     <cmdsynopsis>
  62       <command>udevadm trigger <optional>options</optional> <optional>devpath</optional></command>
  63     </cmdsynopsis>
  64     <cmdsynopsis>
  65       <command>udevadm settle <optional>options</optional></command>
  66     </cmdsynopsis>
  67     <cmdsynopsis>
  68       <command>udevadm control <replaceable>option</replaceable></command>
  69     </cmdsynopsis>
  70     <cmdsynopsis>
  71       <command>udevadm monitor <optional>options</optional></command>
  72     </cmdsynopsis>
  73     <cmdsynopsis>
  74       <command>udevadm test <optional>options</optional> <replaceable>devpath</replaceable></command>
  75     </cmdsynopsis>
  76     <cmdsynopsis>
  77       <command>udevadm test-builtin <optional>options</optional> <replaceable>command</replaceable> <replaceable>devpath</replaceable></command>
  78     </cmdsynopsis>
  79   </refsynopsisdiv>
  80
  81   <refsect1><title>Description</title>
  82     <para><command>udevadm</command> expects a command and command
  83     specific options.  It controls the runtime behavior of
  84     <command>systemd-udevd</command>, requests kernel events, manages
  85     the event queue, and provides simple debugging mechanisms.</para>
  86   </refsect1>
  87
  88   <refsect1><title>Options</title>
  89     <variablelist>
  90       <varlistentry>
  91         <term><option>-d</option></term>
  92         <term><option>--debug</option></term>
  93         <listitem>
  94           <para>Print debug messages to standard error.</para>
  95         </listitem>
  96       </varlistentry>
  97
  98       <xi:include href="standard-options.xml" xpointer="version" />
  99       <xi:include href="standard-options.xml" xpointer="help" />
 100     </variablelist>
 101
 102     <refsect2><title>udevadm info
 103       <arg choice="opt"><replaceable>options</replaceable></arg>
 104       <arg choice="opt"><replaceable>devpath</replaceable>|<replaceable>file</replaceable></arg>
 105     </title>
 106
 107       <para>Queries the udev database for device information
 108       stored in the udev database. It can also query the properties
 109       of a device from its sysfs representation to help creating udev
 110       rules that match this device.</para>
 111       <variablelist>
 112         <varlistentry>
 113           <term><option>-q</option></term>
 114           <term><option>--query=<replaceable>TYPE</replaceable></option></term>
 115           <listitem>
 116             <para>Query the database for the specified type of device
 117             data. It needs the <option>--path</option> or
 118             <option>--name</option> to identify the specified device.
 119             Valid <replaceable>TYPE</replaceable>s are:
 120             <constant>name</constant>, <constant>symlink</constant>,
 121             <constant>path</constant>, <constant>property</constant>,
 122             <constant>all</constant>.</para>
 123           </listitem>
 124         </varlistentry>
 125         <varlistentry>
 126           <term><option>-p</option></term>
 127           <term><option>--path=<replaceable>DEVPATH</replaceable></option></term>
 128           <listitem>
 129             <para>The <filename>/sys</filename> path of the device to
 130             query, e.g.
 131             <filename><optional>/sys</optional>/class/block/sda</filename>.
 132             Note that this option usually is not very useful, since
 133             <command>udev</command> can guess the type of the
 134             argument, so <command>udevadm
 135             --devpath=/class/block/sda</command> is equivalent to
 136             <command>udevadm /sys/class/block/sda</command>.</para>
 137           </listitem>
 138         </varlistentry>
 139         <varlistentry>
 140           <term><option>-n</option></term>
 141           <term><option>--name=<replaceable>FILE</replaceable></option></term>
 142           <listitem>
 143             <para>The name of the device node or a symlink to query,
 144             e.g. <filename><optional>/dev</optional>/sda</filename>.
 145             Note that this option usually is not very useful, since
 146             <command>udev</command> can guess the type of the
 147             argument, so <command>udevadm --name=sda</command> is
 148             equivalent to <command>udevadm /dev/sda</command>.</para>
 149           </listitem>
 150         </varlistentry>
 151         <varlistentry>
 152           <term><option>-r</option></term>
 153           <term><option>--root</option></term>
 154           <listitem>
 155             <para>Print absolute paths in <command>name</command> or <command>symlink</command>
 156             query.</para>
 157           </listitem>
 158         </varlistentry>
 159         <varlistentry>
 160           <term><option>-a</option></term>
 161           <term><option>--attribute-walk</option></term>
 162           <listitem>
 163             <para>Print all sysfs properties of the specified device that can be used
 164             in udev rules to match the specified device. It prints all devices
 165             along the chain, up to the root of sysfs that can be used in udev rules.</para>
 166           </listitem>
 167         </varlistentry>
 168         <varlistentry>
 169           <term><option>-x</option></term>
 170           <term><option>--export</option></term>
 171           <listitem>
 172             <para>Print output as key/value pairs. Values are enclosed in single quotes.</para>
 173           </listitem>
 174         </varlistentry>
 175         <varlistentry>
 176           <term><option>-P</option></term>
 177           <term><option>--export-prefix=<replaceable>NAME</replaceable></option></term>
 178           <listitem>
 179             <para>Add a prefix to the key name of exported values.</para>
 180           </listitem>
 181         </varlistentry>
 182         <varlistentry>
 183           <term><option>-d</option></term>
 184           <term><option>--device-id-of-file=<replaceable>FILE</replaceable></option></term>
 185           <listitem>
 186             <para>Print major/minor numbers of the underlying device, where the file
 187             lives on.</para>
 188           </listitem>
 189         </varlistentry>
 190         <varlistentry>
 191           <term><option>-e</option></term>
 192           <term><option>--export-db</option></term>
 193           <listitem>
 194             <para>Export the content of the udev database.</para>
 195           </listitem>
 196         </varlistentry>
 197         <varlistentry>
 198           <term><option>-c</option></term>
 199           <term><option>--cleanup-db</option></term>
 200           <listitem>
 201             <para>Cleanup the udev database.</para>
 202           </listitem>
 203         </varlistentry>
 204
 205         <xi:include href="standard-options.xml" xpointer="version" />
 206         <xi:include href="standard-options.xml" xpointer="help" />
 207       </variablelist>
 208
 209       <para>In addition, an optional positional argument can be used
 210       to specify a device name or a sys path. It must start with
 211       <filename>/dev</filename> or <filename>/sys</filename>
 212       respectively.</para>
 213     </refsect2>
 214
 215     <refsect2><title>udevadm trigger
 216       <arg choice="opt"><replaceable>options</replaceable></arg>
 217       <arg choice="opt" rep="repeat"><replaceable>devpath</replaceable>|<replaceable>file</replaceable></arg></title>
 218       <para>Request device events from the kernel. Primarily used to replay events at system coldplug time.</para>
 219       <variablelist>
 220         <varlistentry>
 221           <term><option>-v</option></term>
 222           <term><option>--verbose</option></term>
 223           <listitem>
 224             <para>Print the list of devices which will be triggered.</para>
 225           </listitem>
 226         </varlistentry>
 227         <varlistentry>
 228           <term><option>-n</option></term>
 229           <term><option>--dry-run</option></term>
 230           <listitem>
 231             <para>Do not actually trigger the event.</para>
 232           </listitem>
 233         </varlistentry>
 234         <varlistentry>
 235           <term><option>-t</option></term>
 236           <term><option>--type=<replaceable>TYPE</replaceable></option></term>
 237           <listitem>
 238             <para>Trigger a specific type of devices. Valid types are:
 239             <command>devices</command>, <command>subsystems</command>.
 240             The default value is <command>devices</command>.</para>
 241           </listitem>
 242         </varlistentry>
 243         <varlistentry>
 244           <term><option>-c</option></term>
 245           <term><option>--action=<replaceable>ACTION</replaceable></option></term>
 246           <listitem>
 247             <para>Type of event to be triggered. The default value is
 248             <command>change</command>.</para>
 249           </listitem>
 250         </varlistentry>
 251         <varlistentry>
 252           <term><option>-s</option></term>
 253           <term><option>--subsystem-match=<replaceable>SUBSYSTEM</replaceable></option></term>
 254           <listitem>
 255             <para>Trigger events for devices which belong to a
 256             matching subsystem. This option can be specified multiple
 257             times and supports shell style pattern matching.</para>
 258           </listitem>
 259         </varlistentry>
 260         <varlistentry>
 261           <term><option>-S</option></term>
 262           <term><option>--subsystem-nomatch=<replaceable>SUBSYSTEM</replaceable></option></term>
 263           <listitem>
 264             <para>Do not trigger events for devices which belong to a matching subsystem. This option
 265             can be specified multiple times and supports shell style pattern matching.</para>
 266           </listitem>
 267         </varlistentry>
 268         <varlistentry>
 269           <term><option>-a</option></term>
 270           <term><option>--attr-match=<replaceable>ATTRIBUTE</replaceable>=<replaceable>VALUE</replaceable></option></term>
 271           <listitem>
 272             <para>Trigger events for devices with a matching sysfs
 273             attribute. If a value is specified along with the
 274             attribute name, the content of the attribute is matched
 275             against the given value using shell style pattern
 276             matching. If no value is specified, the existence of the
 277             sysfs attribute is checked. This option can be specified
 278             multiple times.</para>
 279           </listitem>
 280         </varlistentry>
 281         <varlistentry>
 282           <term><option>-A</option></term>
 283           <term><option>--attr-nomatch=<replaceable>ATTRIBUTE</replaceable>=<replaceable>VALUE</replaceable></option></term>
 284           <listitem>
 285             <para>Do not trigger events for devices with a matching
 286             sysfs attribute. If a value is specified along with the
 287             attribute name, the content of the attribute is matched
 288             against the given value using shell style pattern
 289             matching. If no value is specified, the existence of the
 290             sysfs attribute is checked. This option can be specified
 291             multiple times.</para>
 292           </listitem>
 293         </varlistentry>
 294         <varlistentry>
 295           <term><option>-p</option></term>
 296           <term><option>--property-match=<replaceable>PROPERTY</replaceable>=<replaceable>VALUE</replaceable></option></term>
 297           <listitem>
 298             <para>Trigger events for devices with a matching property
 299             value. This option can be specified multiple times and
 300             supports shell style pattern matching.</para>
 301           </listitem>
 302         </varlistentry>
 303         <varlistentry>
 304           <term><option>-g</option></term>
 305           <term><option>--tag-match=<replaceable>PROPERTY</replaceable></option></term>
 306           <listitem>
 307             <para>Trigger events for devices with a matching tag. This
 308             option can be specified multiple times.</para>
 309           </listitem>
 310         </varlistentry>
 311         <varlistentry>
 312           <term><option>-y</option></term>
 313           <term><option>--sysname-match=<replaceable>PATH</replaceable></option></term>
 314           <listitem>
 315             <para>Trigger events for devices for which the last component
 316             (i.e. the filename) of the <filename>/sys</filename> path matches
 317             the specified <replaceable>PATH</replaceable>. This option can be
 318             specified multiple times and also supports shell style pattern
 319             matching.</para>
 320           </listitem>
 321         </varlistentry>
 322         <varlistentry>
 323           <term><option>--name-match=<replaceable>NAME</replaceable></option></term>
 324           <listitem>
 325             <para>Trigger events for devices with a matching
 326             device path. This option can be specified multiple
 327             times.</para>
 328           </listitem>
 329         </varlistentry>
 330         <varlistentry>
 331           <term><option>-b</option></term>
 332           <term><option>--parent-match=<replaceable>SYSPATH</replaceable></option></term>
 333           <listitem>
 334             <para>Trigger events for all children of a given
 335             device.</para>
 336           </listitem>
 337         </varlistentry>
 338
 339         <xi:include href="standard-options.xml" xpointer="version" />
 340         <xi:include href="standard-options.xml" xpointer="help" />
 341       </variablelist>
 342
 343       <para>In addition, optional positional arguments can be used
 344       to specify device names or sys paths. They must start with
 345       <filename>/dev</filename> or <filename>/sys</filename>
 346       respectively.</para>
 347     </refsect2>
 348
 349     <refsect2><title>udevadm settle
 350       <arg choice="opt"><replaceable>options</replaceable></arg>
 351     </title>
 352       <para>Watches the udev event queue, and exits if all current events are handled.</para>
 353       <variablelist>
 354         <varlistentry>
 355           <term><option>-t</option></term>
 356           <term><option>--timeout=<replaceable>SECONDS</replaceable></option></term>
 357           <listitem>
 358             <para>Maximum number of seconds to wait for the event
 359             queue to become empty. The default value is 120 seconds. A
 360             value of 0 will check if the queue is empty and always
 361             return immediately.</para>
 362           </listitem>
 363         </varlistentry>
 364         <varlistentry>
 365           <term><option>-E</option></term>
 366           <term><option>--exit-if-exists=<replaceable>FILE</replaceable></option></term>
 367           <listitem>
 368             <para>Stop waiting if file exists.</para>
 369           </listitem>
 370         </varlistentry>
 371
 372         <xi:include href="standard-options.xml" xpointer="version" />
 373         <xi:include href="standard-options.xml" xpointer="help" />
 374       </variablelist>
 375     </refsect2>
 376
 377     <refsect2><title>udevadm control <replaceable>option</replaceable></title>
 378       <para>Modify the internal state of the running udev daemon.</para>
 379       <variablelist>
 380         <varlistentry>
 381           <term><option>-e</option></term>
 382           <term><option>--exit</option></term>
 383           <listitem>
 384             <para>Signal and wait for systemd-udevd to exit.</para>
 385           </listitem>
 386         </varlistentry>
 387         <varlistentry>
 388           <term><option>-l</option></term>
 389           <term><option>--log-priority=<replaceable>value</replaceable></option></term>
 390           <listitem>
 391             <para>Set the internal log level of
 392             <filename>systemd-udevd</filename>. Valid values are the
 393             numerical syslog priorities or their textual
 394             representations: <option>emerg</option>,
 395             <option>alert</option>, <option>crit</option>,
 396             <option>err</option>, <option>warning</option>,
 397             <option>notice</option>, <option>info</option>, and
 398             <option>debug</option>.</para>
 399           </listitem>
 400         </varlistentry>
 401         <varlistentry>
 402           <term><option>-s</option></term>
 403           <term><option>--stop-exec-queue</option></term>
 404           <listitem>
 405             <para>Signal systemd-udevd to stop executing new events. Incoming events
 406             will be queued.</para>
 407           </listitem>
 408         </varlistentry>
 409         <varlistentry>
 410           <term><option>-S</option></term>
 411           <term><option>--start-exec-queue</option></term>
 412           <listitem>
 413             <para>Signal systemd-udevd to enable the execution of events.</para>
 414           </listitem>
 415         </varlistentry>
 416         <varlistentry>
 417           <term><option>-R</option></term>
 418           <term><option>--reload</option></term>
 419           <listitem>
 420             <para>Signal systemd-udevd to reload the rules files and other databases like the kernel
 421             module index. Reloading rules and databases does not apply any changes to already
 422             existing devices; the new configuration will only be applied to new events.</para>
 423           </listitem>
 424         </varlistentry>
 425         <varlistentry>
 426           <term><option>-p</option></term>
 427           <term><option>--property=<replaceable>KEY</replaceable>=<replaceable>value</replaceable></option></term>
 428           <listitem>
 429             <para>Set a global property for all events.</para>
 430           </listitem>
 431         </varlistentry>
 432         <varlistentry>
 433           <term><option>-m</option></term>
 434           <term><option>--children-max=</option><replaceable>value</replaceable></term>
 435           <listitem>
 436             <para>Set the maximum number of events, systemd-udevd will handle at the
 437             same time.</para>
 438           </listitem>
 439         </varlistentry>
 440         <varlistentry>
 441           <term><option>-t</option></term>
 442           <term><option>--timeout=</option><replaceable>seconds</replaceable></term>
 443           <listitem>
 444             <para>The maximum number of seconds to wait for a reply from systemd-udevd.</para>
 445           </listitem>
 446         </varlistentry>
 447
 448         <xi:include href="standard-options.xml" xpointer="version" />
 449         <xi:include href="standard-options.xml" xpointer="help" />
 450       </variablelist>
 451     </refsect2>
 452
 453     <refsect2><title>udevadm monitor
 454       <arg choice="opt"><replaceable>options</replaceable></arg>
 455     </title>
 456       <para>Listens to the kernel uevents and events sent out by a udev rule
 457       and prints the devpath of the event to the console. It can be used to analyze the
 458       event timing, by comparing the timestamps of the kernel uevent and the udev event.
 459       </para>
 460       <variablelist>
 461         <varlistentry>
 462           <term><option>-k</option></term>
 463           <term><option>--kernel</option></term>
 464           <listitem>
 465             <para>Print the kernel uevents.</para>
 466           </listitem>
 467         </varlistentry>
 468         <varlistentry>
 469           <term><option>-u</option></term>
 470           <term><option>--udev</option></term>
 471           <listitem>
 472             <para>Print the udev event after the rule processing.</para>
 473           </listitem>
 474         </varlistentry>
 475         <varlistentry>
 476           <term><option>-p</option></term>
 477           <term><option>--property</option></term>
 478           <listitem>
 479             <para>Also print the properties of the event.</para>
 480           </listitem>
 481         </varlistentry>
 482         <varlistentry>
 483           <term><option>-s</option></term>
 484           <term><option>--subsystem-match=<replaceable>string[/string]</replaceable></option></term>
 485           <listitem>
 486             <para>Filter kernel uevents and udev events by subsystem[/devtype]. Only events with a matching subsystem value will pass.</para>
 487           </listitem>
 488         </varlistentry>
 489         <varlistentry>
 490           <term><option>-t</option></term>
 491           <term><option>--tag-match=<replaceable>string</replaceable></option></term>
 492           <listitem>
 493             <para>Filter udev events by tag. Only udev events with a given tag attached will pass.</para>
 494           </listitem>
 495         </varlistentry>
 496
 497         <xi:include href="standard-options.xml" xpointer="version" />
 498         <xi:include href="standard-options.xml" xpointer="help" />
 499       </variablelist>
 500     </refsect2>
 501
 502     <refsect2><title>udevadm test
 503       <arg choice="opt"><replaceable>options</replaceable></arg>
 504       <arg><replaceable>devpath</replaceable></arg>
 505     </title>
 506       <para>Simulate a udev event run for the given device, and print debug output.</para>
 507       <variablelist>
 508         <varlistentry>
 509           <term><option>-a</option></term>
 510           <term><option>--action=<replaceable>string</replaceable></option></term>
 511           <listitem>
 512             <para>The action string.</para>
 513           </listitem>
 514         </varlistentry>
 515         <varlistentry>
 516           <term><option>-N</option></term>
 517           <term><option>--resolve-names=<constant>early</constant>|<constant>late</constant>|<constant>never</constant></option></term>
 518           <listitem>
 519             <para>Specify when udevadm should resolve names of users
 520             and groups.  When set to <constant>early</constant> (the
 521             default), names will be resolved when the rules are
 522             parsed. When set to <constant>late</constant>, names will
 523             be resolved for every event. When set to
 524             <constant>never</constant>, names will never be resolved
 525             and all devices will be owned by root.</para>
 526           </listitem>
 527         </varlistentry>
 528
 529         <xi:include href="standard-options.xml" xpointer="version" />
 530         <xi:include href="standard-options.xml" xpointer="help" />
 531       </variablelist>
 532     </refsect2>
 533
 534     <refsect2><title>udevadm test-builtin
 535       <arg choice="opt"><replaceable>options</replaceable></arg>
 536       <arg><replaceable>command</replaceable></arg>
 537       <arg><replaceable>devpath</replaceable></arg>
 538     </title>
 539       <para>Run a built-in command <replaceable>COMMAND</replaceable>
 540       for device <replaceable>DEVPATH</replaceable>, and print debug
 541       output.</para>
 542       <variablelist>
 543         <xi:include href="standard-options.xml" xpointer="version" />
 544         <xi:include href="standard-options.xml" xpointer="help" />
 545       </variablelist>
 546     </refsect2>
 547   </refsect1>
 548
 549   <refsect1>
 550     <title>See Also</title>
 551     <para><citerefentry>
 552         <refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum>
 553     </citerefentry>,
 554     <citerefentry>
 555         <refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum>
 556     </citerefentry></para>
 557   </refsect1>
 558 </refentry>