man/busctl.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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   6 This file is part of systemd.
   7
   8 Copyright 2014 Zbigniew Jędrzejewski-Szmek
   9
  10 systemd is free software; you can redistribute it and/or modify it
  11 under the terms of the GNU Lesser General Public License as published by
  12 the Free Software Foundation; either version 2.1 of the License, or
  13 (at your option) any later version.
  14
  15 systemd is distributed in the hope that it will be useful, but
  16 WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18 Lesser General Public License for more details.
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  21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
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  23
  24 <refentry id="busctl"
  25           xmlns:xi="http://www.w3.org/2001/XInclude">
  26
  27   <refentryinfo>
  28     <title>busctl</title>
  29     <productname>systemd</productname>
  30
  31     <authorgroup>
  32       <author>
  33         <contrib>A monkey with a typewriter</contrib>
  34         <firstname>Zbigniew</firstname>
  35         <surname>Jędrzejewski-Szmek</surname>
  36         <email>zbyszek@in.waw.pl</email>
  37       </author>
  38     </authorgroup>
  39   </refentryinfo>
  40
  41   <refmeta>
  42     <refentrytitle>busctl</refentrytitle>
  43     <manvolnum>1</manvolnum>
  44   </refmeta>
  45
  46   <refnamediv>
  47     <refname>busctl</refname>
  48     <refpurpose>Introspect the bus</refpurpose>
  49   </refnamediv>
  50
  51   <refsynopsisdiv>
  52     <cmdsynopsis>
  53       <command>busctl</command>
  54       <arg choice="opt" rep="repeat">OPTIONS</arg>
  55       <arg choice="opt">COMMAND</arg>
  56       <arg choice="opt" rep="repeat"><replaceable>NAME</replaceable></arg>
  57     </cmdsynopsis>
  58   </refsynopsisdiv>
  59
  60   <refsect1>
  61     <title>Description</title>
  62
  63     <para><command>busctl</command> may be used to
  64     introspect and monitor the D-Bus bus.</para>
  65   </refsect1>
  66
  67   <refsect1>
  68     <title>Options</title>
  69
  70     <para>The following options are understood:</para>
  71
  72     <variablelist>
  73       <varlistentry>
  74           <term><option>--address=<replaceable>ADDRESS</replaceable></option></term>
  75
  76           <listitem><para>Connect to the bus specified by
  77           <replaceable>ADDRESS</replaceable> instead of using suitable
  78           defaults for either the system or user bus (see
  79           <option>--system</option> and <option>--user</option>
  80           options).</para></listitem>
  81       </varlistentry>
  82
  83       <varlistentry>
  84           <term><option>--show-machine</option></term>
  85
  86           <listitem><para>When showing the list of endpoints, show a
  87           column containing the names of containers they belong to.
  88           See
  89           <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  90           </para></listitem>
  91       </varlistentry>
  92
  93       <varlistentry>
  94           <term><option>--unique</option></term>
  95
  96           <listitem><para>When showing the list of endpoints, show
  97           only "unique" names (of the form
  98           <literal>:<replaceable>number</replaceable>.<replaceable>number</replaceable></literal>).
  99           </para></listitem>
 100       </varlistentry>
 101
 102       <varlistentry>
 103           <term><option>--acquired</option></term>
 104
 105           <listitem><para>The opposite of <option>--unique</option> —
 106           only "well-known" names will be shown.</para></listitem>
 107       </varlistentry>
 108
 109       <varlistentry>
 110           <term><option>--activatable</option></term>
 111
 112           <listitem><para>When showing the list of endpoints, show
 113           only endpoints which have actually not been activated yet,
 114           but may be started automatically if accessed.</para>
 115           </listitem>
 116       </varlistentry>
 117
 118       <varlistentry>
 119           <term><option>--match=<replaceable>MATCH</replaceable></option></term>
 120
 121           <listitem><para>When showing messages being exchanged, show only the
 122           subset matching <replaceable>MATCH</replaceable>.</para></listitem>
 123           <!-- TODO: link to sd_bus_add_match when it is written? -->
 124       </varlistentry>
 125
 126       <varlistentry>
 127         <term><option>--no-legend</option></term>
 128
 129         <listitem>
 130           <para>Do not print the legend,
 131           i.e. the column headers and the
 132           footer.</para>
 133         </listitem>
 134       </varlistentry>
 135
 136       <varlistentry>
 137         <term><option>--size=</option></term>
 138
 139         <listitem>
 140           <para>When used with the <command>capture</command> command
 141           specifies the maximum bus message size to capture
 142           ("snaplen"). Defaults to 4096 bytes.</para>
 143         </listitem>
 144       </varlistentry>
 145
 146       <varlistentry>
 147         <term><option>--list</option></term>
 148
 149         <listitem>
 150           <para>When used with the <command>tree</command> command shows a
 151           flat list of object paths instead of a tree.</para>
 152         </listitem>
 153       </varlistentry>
 154
 155       <varlistentry>
 156         <term><option>--quiet</option></term>
 157
 158         <listitem>
 159           <para>When used with the <command>call</command> command
 160           suppresses display of the response message payload. Note that even
 161           if this option is specified errors returned will still be
 162           printed and the tool will indicate success or failure with
 163           the process exit code.</para>
 164         </listitem>
 165       </varlistentry>
 166
 167       <varlistentry>
 168         <term><option>--verbose</option></term>
 169
 170         <listitem>
 171           <para>When used with the <command>call</command> or
 172           <command>get-property</command> command shows output in a
 173           more verbose format.</para>
 174         </listitem>
 175       </varlistentry>
 176
 177       <varlistentry>
 178         <term><option>--expect-reply=</option><replaceable>BOOL</replaceable></term>
 179
 180         <listitem>
 181           <para>When used with the <command>call</command> command
 182           specifies whether <command>busctl</command> shall wait for
 183           completion of the method call, output the returned method
 184           response data, and return success or failure via the process
 185           exit code. If this is set to <literal>no</literal> the
 186           method call will be issued but no response is expected, the
 187           tool terminates immediately, and thus no response can be
 188           shown, and no success or failure is returned via the exit
 189           code. To only suppress output of the reply message payload
 190           use <option>--quiet</option> above. Defaults to
 191           <literal>yes</literal>.</para>
 192         </listitem>
 193       </varlistentry>
 194
 195       <varlistentry>
 196         <term><option>--auto-start=</option><replaceable>BOOL</replaceable></term>
 197
 198         <listitem>
 199           <para>When used with the <command>call</command> command specifies
 200           whether the method call should implicitly activate the
 201           called service should it not be running yet but is
 202           configured to be auto-started. Defaults to
 203           <literal>yes</literal>.</para>
 204         </listitem>
 205       </varlistentry>
 206
 207       <varlistentry>
 208         <term><option>--allow-interactive-authorization=</option><replaceable>BOOL</replaceable></term>
 209
 210         <listitem>
 211           <para>When used with the <command>call</command> command
 212           specifies whether the services may enforce interactive
 213           authorization while executing the operation, if the security
 214           policy is configured for this. Defaults to
 215           <literal>yes</literal>.</para>
 216         </listitem>
 217       </varlistentry>
 218
 219       <xi:include href="user-system-options.xml" xpointer="user" />
 220       <xi:include href="user-system-options.xml" xpointer="system" />
 221       <xi:include href="user-system-options.xml" xpointer="host" />
 222       <xi:include href="user-system-options.xml" xpointer="machine" />
 223
 224       <xi:include href="standard-options.xml" xpointer="help" />
 225       <xi:include href="standard-options.xml" xpointer="version" />
 226       <xi:include href="standard-options.xml" xpointer="no-pager" />
 227     </variablelist>
 228   </refsect1>
 229
 230   <refsect1>
 231     <title>Commands</title>
 232
 233     <para>The following commands are understood:</para>
 234
 235     <variablelist>
 236       <varlistentry>
 237         <term><command>list</command></term>
 238
 239         <listitem><para>Show service names on the bus. This is the
 240         default if no command is specified.</para></listitem>
 241       </varlistentry>
 242
 243       <varlistentry>
 244         <term><command>status</command> <arg choice="plain"><replaceable>SERVICE</replaceable></arg></term>
 245
 246         <listitem><para>Show process information and credentials of a
 247         bus service.</para></listitem>
 248       </varlistentry>
 249
 250       <varlistentry>
 251         <term><command>monitor</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
 252
 253         <listitem><para>Dump messages being exchanged. If
 254         <replaceable>SERVICE</replaceable> is specified, show messages
 255         to or from this endpoint. Otherwise, show all messages on the
 256         bus. Use Ctrl-C to terminate dump.</para></listitem>
 257       </varlistentry>
 258
 259       <varlistentry>
 260         <term><command>capture</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
 261
 262         <listitem><para>Similar to <command>monitor</command> but
 263         writes the output in pcap format (for details see the <ulink
 264         url="http://wiki.wireshark.org/Development/LibpcapFileFormat">Libpcap
 265         File Format</ulink> description. Make sure to redirect the
 266         output to STDOUT to a file. Tools like
 267         <citerefentry><refentrytitle>wireshark</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 268         may be used to dissect and view the generated
 269         files.</para></listitem>
 270       </varlistentry>
 271
 272       <varlistentry>
 273         <term><command>tree</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
 274
 275         <listitem><para>Shows an object tree of one or more
 276         services. If <replaceable>SERVICE</replaceable> is specified,
 277         show object tree of the specified services only. Otherwise,
 278         show all object trees of all services on the bus that acquired
 279         at least one well-known name.</para></listitem>
 280       </varlistentry>
 281
 282       <varlistentry>
 283         <term><command>introspect</command> <arg choice="plain"><replaceable>SERVICE</replaceable></arg> <arg choice="plain"><replaceable>OBJECT</replaceable></arg></term>
 284
 285         <listitem><para>Show interfaces, methods, properties and
 286         signals of the specified object (identified by its path) on
 287         the specified service.</para></listitem>
 288       </varlistentry>
 289
 290       <varlistentry>
 291         <term><command>call</command> <arg choice="plain"><replaceable>SERVICE</replaceable></arg> <arg choice="plain"><replaceable>OBJECT</replaceable></arg> <arg choice="plain"><replaceable>INTERFACE</replaceable></arg> <arg choice="plain"><replaceable>METHOD</replaceable></arg> <arg choice="opt"><replaceable>SIGNATURE</replaceable> <arg choice="opt" rep="repeat"><replaceable>ARGUMENT</replaceable></arg></arg></term>
 292
 293         <listitem><para>Invoke a method and show the response. Takes a
 294         service name, object path, interface name and method name. If
 295         parameters shall be passed to the method call a signature
 296         string is required, followed by the arguments, individually
 297         formatted as strings. For details on the formatting used, see
 298         below. To suppress output of the returned data use the
 299         <option>--quiet</option> option.</para></listitem>
 300       </varlistentry>
 301
 302       <varlistentry>
 303         <term><command>get-property</command> <arg choice="plain"><replaceable>SERVICE</replaceable></arg> <arg choice="plain"><replaceable>OBJECT</replaceable></arg> <arg choice="plain"><replaceable>INTERFACE</replaceable></arg> <arg choice="plain" rep="repeat"><replaceable>PROPERTY</replaceable></arg></term>
 304
 305         <listitem><para>Retrieve the current value of one or more
 306         object properties. Takes a service name, object path,
 307         interface name and property name. Multiple properties may be
 308         specified at once in which case their values will be shown one
 309         after the other, separated by newlines. The output is by
 310         default in terse format. Use <option>--verbose</option> for a
 311         more elaborate output format.</para></listitem>
 312       </varlistentry>
 313
 314       <varlistentry>
 315         <term><command>set-property</command> <arg choice="plain"><replaceable>SERVICE</replaceable></arg> <arg choice="plain"><replaceable>OBJECT</replaceable></arg> <arg choice="plain"><replaceable>INTERFACE</replaceable></arg> <arg choice="plain"><replaceable>PROPERTY</replaceable></arg> <arg choice="plain"><replaceable>SIGNATURE</replaceable></arg> <arg choice="plain" rep="repeat"><replaceable>ARGUMENT</replaceable></arg></term>
 316
 317         <listitem><para>Set the current value an object
 318         property. Takes a service name, object path, interface name,
 319         property name, property signature, followed by a list of
 320         parameters formatted as strings.</para></listitem>
 321       </varlistentry>
 322
 323       <varlistentry>
 324         <term><command>help</command></term>
 325
 326         <listitem><para>Show command syntax help.</para></listitem>
 327       </varlistentry>
 328     </variablelist>
 329   </refsect1>
 330
 331   <refsect1>
 332           <title>Parameter Formatting</title>
 333
 334           <para>The <command>call</command> and
 335           <command>set-property</command> commands take a signature
 336           string followed by a list of parameters formatted as string
 337           (for details on D-Bus signature strings see the <ulink
 338           url="http://dbus.freedesktop.org/doc/dbus-specification.html#type-system">Type
 339           system chapter of the D-Bus specification</ulink>). For
 340           simple types each parameter following the signature should
 341           simply be the parameter's value formatted as
 342           string. Positive boolean values may be formatted as
 343           <literal>true</literal>, <literal>yes</literal>,
 344           <literal>on</literal>, <literal>1</literal>; negative
 345           boolean values may be specified as <literal>false</literal>,
 346           <literal>no</literal>, <literal>off</literal>,
 347           <literal>0</literal>. For arrays, a numeric argument for the
 348           number of entries followed by the entries shall be
 349           specified. For variants the signature of the contents shall
 350           be specified, followed by the contents. For dictionaries and
 351           structs the contents of them shall be directly
 352           specified.</para>
 353
 354           <para>For example,
 355           <programlisting>s jawoll</programlisting> is the formatting
 356           of a single string <literal>jawoll</literal>.</para>
 357
 358           <para>
 359           <programlisting>as 3 hello world foobar</programlisting>
 360           is the formatting of a string array with three entries,
 361           <literal>hello</literal>, <literal>world</literal> and
 362           <literal>foobar</literal>.</para>
 363
 364           <para>
 365           <programlisting>a{sv} 3 One s Eins Two u 2 Yes b true</programlisting>
 366           is the formatting of a dictionary
 367           array that maps strings to variants, consisting of three
 368           entries. The string <literal>One</literal> is assigned the
 369           string <literal>Eins</literal>. The string
 370           <literal>Two</literal> is assigned the 32bit unsigned
 371           integer 2. The string <literal>Yes</literal> is assigned a
 372           positive boolean.</para>
 373
 374           <para>Note that the <command>call</command>,
 375           <command>get-property</command>,
 376           <command>introspect</command> commands will also generate
 377           output in this format for the returned data. Since this
 378           format is sometimes too terse to be easily understood, the
 379           <command>call</command> and <command>get-property</command>
 380           commands may generate a more verbose, multi-line output when
 381           passed the <option>--verbose</option> option.</para>
 382   </refsect1>
 383
 384   <refsect1>
 385           <title>Examples</title>
 386
 387           <example>
 388                   <title>Write and Read a Property</title>
 389
 390                   <para>The following two commands first write a
 391                   property and then read it back. The property is
 392                   found on the
 393                   <literal>/org/freedesktop/systemd1</literal> object
 394                   of the <literal>org.freedesktop.systemd1</literal>
 395                   service. The name of the property is
 396                   <literal>LogLevel</literal> on the
 397                   <literal>org.freedesktop.systemd1.Manager</literal>
 398                   interface. The property contains a single
 399                   string:</para>
 400
 401                   <programlisting># busctl set-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager LogLevel s debug
 402 # busctl get-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager LogLevel
 403 s "debug"</programlisting>
 404
 405           </example>
 406
 407           <example>
 408                   <title>Terse and Verbose Output</title>
 409
 410                   <para>The following two commands read a property that
 411                   contains an array of strings, and first show it in
 412                   terse format, followed by verbose format:</para>
 413
 414                   <programlisting>$ busctl get-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager Environment
 415 as 2 "LANG=en_US.UTF-8" "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin"
 416 $ busctl get-property --verbose org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager Environment
 417 ARRAY "s" {
 418         STRING "LANG=en_US.UTF-8";
 419         STRING "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin";
 420 };</programlisting>
 421           </example>
 422
 423         <example>
 424                   <title>Invoking a Method</title>
 425
 426                   <para>The following command invokes a the
 427                   <literal>StartUnit</literal> method on the
 428                   <literal>org.freedesktop.systemd1.Manager</literal>
 429                   interface of the
 430                   <literal>/org/freedesktop/systemd1</literal> object
 431                   of the <literal>org.freedesktop.systemd1</literal>
 432                   service, and passes it two strings
 433                   <literal>cups.service</literal> and
 434                   <literal>replace</literal>. As result of the method
 435                   call a single object path parameter is received and
 436                   shown:</para>
 437
 438                   <programlisting># busctl call org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager StartUnit ss "cups.service" "replace"
 439 o "/org/freedesktop/systemd1/job/42684"</programlisting>
 440         </example>
 441   </refsect1>
 442
 443   <refsect1>
 444     <title>See Also</title>
 445
 446     <para>
 447       <citerefentry><refentrytitle>dbus-daemon</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 448       <ulink url="http://freedesktop.org/wiki/Software/dbus">D-Bus</ulink>,
 449       <ulink url="https://code.google.com/p/d-bus/">kdbus</ulink>,
 450       <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 451       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 452       <citerefentry><refentrytitle>systemd-bus-proxyd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 453       <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 454       <citerefentry><refentrytitle>wireshark</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 455     </para>
 456   </refsect1>
 457 </refentry>