1 <?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
6 This file is part of systemd.
8 Copyright 2014 Zbigniew Jędrzejewski-Szmek
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.
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.
20 You should have received a copy of the GNU Lesser General Public License
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25 xmlns:xi="http://www.w3.org/2001/XInclude">
29 <productname>systemd</productname>
33 <contrib>A monkey with a typewriter</contrib>
34 <firstname>Zbigniew</firstname>
35 <surname>Jędrzejewski-Szmek</surname>
36 <email>zbyszek@in.waw.pl</email>
42 <refentrytitle>busctl</refentrytitle>
43 <manvolnum>1</manvolnum>
47 <refname>busctl</refname>
48 <refpurpose>Introspect the bus</refpurpose>
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>
61 <title>Description</title>
63 <para><command>busctl</command> may be used to
64 introspect and monitor the D-Bus bus.</para>
68 <title>Options</title>
70 <para>The following options are understood:</para>
74 <term><option>--address=<replaceable>ADDRESS</replaceable></option></term>
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>
84 <term><option>--show-machine</option></term>
86 <listitem><para>When showing the list of endpoints, show a
87 column containing the names of containers they belong to.
89 <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
94 <term><option>--unique</option></term>
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>).
103 <term><option>--acquired</option></term>
105 <listitem><para>The opposite of <option>--unique</option> —
106 only "well-known" names will be shown.</para></listitem>
110 <term><option>--activatable</option></term>
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>
119 <term><option>--match=<replaceable>MATCH</replaceable></option></term>
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? -->
127 <term><option>--no-legend</option></term>
130 <para>Do not print the legend,
131 i.e. the column headers and the
137 <term><option>--size=</option></term>
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>
147 <term><option>--list</option></term>
150 <para>When used with the <command>tree</command> command shows a
151 flat list of object paths instead of a tree.</para>
156 <term><option>--quiet</option></term>
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>
168 <term><option>--verbose</option></term>
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>
178 <term><option>--expect-reply=</option><replaceable>BOOL</replaceable></term>
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>
196 <term><option>--auto-start=</option><replaceable>BOOL</replaceable></term>
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>
208 <term><option>--allow-interactive-authorization=</option><replaceable>BOOL</replaceable></term>
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>
220 <term><option>--timeout=</option><replaceable>SECS</replaceable></term>
223 <para>When used with the <command>call</command> command
224 specifies the maximum time to wait for method call
225 completion. If no time unit is specified assumes
226 seconds. The usual other units are understood, too (ms, us,
227 s, min, h, d, w, month, y). Note that this timeout does not
228 apply if <option>--expect-reply=no</option> is used as the
229 tool does not wait for any reply message then. When not
230 specified or when set to 0 the default of
231 <literal>25s</literal> is assumed.</para>
236 <term><option>--augment-creds=</option><replaceable>BOOL</replaceable></term>
239 <para>Controls whether credential data reported by
240 <command>list</command> or <command>status</command> shall
241 be augmented with data from
242 <filename>/proc</filename>. When this is turned on the data
243 shown is possibly inconsistent, as the data read from
244 <filename>/proc</filename> might be more recent than rest of
245 the credential information. Defaults to <literal>yes</literal>.</para>
249 <xi:include href="user-system-options.xml" xpointer="user" />
250 <xi:include href="user-system-options.xml" xpointer="system" />
251 <xi:include href="user-system-options.xml" xpointer="host" />
252 <xi:include href="user-system-options.xml" xpointer="machine" />
254 <xi:include href="standard-options.xml" xpointer="help" />
255 <xi:include href="standard-options.xml" xpointer="version" />
256 <xi:include href="standard-options.xml" xpointer="no-pager" />
261 <title>Commands</title>
263 <para>The following commands are understood:</para>
267 <term><command>list</command></term>
269 <listitem><para>Show service names on the bus. This is the
270 default if no command is specified.</para></listitem>
274 <term><command>status</command> <arg choice="plain"><replaceable>SERVICE</replaceable></arg></term>
276 <listitem><para>Show process information and credentials of a
277 bus service.</para></listitem>
281 <term><command>monitor</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
283 <listitem><para>Dump messages being exchanged. If
284 <replaceable>SERVICE</replaceable> is specified, show messages
285 to or from this endpoint. Otherwise, show all messages on the
286 bus. Use Ctrl-C to terminate dump.</para></listitem>
290 <term><command>capture</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
292 <listitem><para>Similar to <command>monitor</command> but
293 writes the output in pcap format (for details see the <ulink
294 url="http://wiki.wireshark.org/Development/LibpcapFileFormat">Libpcap
295 File Format</ulink> description. Make sure to redirect the
296 output to STDOUT to a file. Tools like
297 <citerefentry><refentrytitle>wireshark</refentrytitle><manvolnum>1</manvolnum></citerefentry>
298 may be used to dissect and view the generated
299 files.</para></listitem>
303 <term><command>tree</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
305 <listitem><para>Shows an object tree of one or more
306 services. If <replaceable>SERVICE</replaceable> is specified,
307 show object tree of the specified services only. Otherwise,
308 show all object trees of all services on the bus that acquired
309 at least one well-known name.</para></listitem>
313 <term><command>introspect</command> <arg choice="plain"><replaceable>SERVICE</replaceable></arg> <arg choice="plain"><replaceable>OBJECT</replaceable></arg></term>
315 <listitem><para>Show interfaces, methods, properties and
316 signals of the specified object (identified by its path) on
317 the specified service.</para></listitem>
321 <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>
323 <listitem><para>Invoke a method and show the response. Takes a
324 service name, object path, interface name and method name. If
325 parameters shall be passed to the method call a signature
326 string is required, followed by the arguments, individually
327 formatted as strings. For details on the formatting used, see
328 below. To suppress output of the returned data use the
329 <option>--quiet</option> option.</para></listitem>
333 <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>
335 <listitem><para>Retrieve the current value of one or more
336 object properties. Takes a service name, object path,
337 interface name and property name. Multiple properties may be
338 specified at once in which case their values will be shown one
339 after the other, separated by newlines. The output is by
340 default in terse format. Use <option>--verbose</option> for a
341 more elaborate output format.</para></listitem>
345 <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>
347 <listitem><para>Set the current value an object
348 property. Takes a service name, object path, interface name,
349 property name, property signature, followed by a list of
350 parameters formatted as strings.</para></listitem>
354 <term><command>help</command></term>
356 <listitem><para>Show command syntax help.</para></listitem>
362 <title>Parameter Formatting</title>
364 <para>The <command>call</command> and
365 <command>set-property</command> commands take a signature string
366 followed by a list of parameters formatted as string (for details
367 on D-Bus signature strings see the <ulink
368 url="http://dbus.freedesktop.org/doc/dbus-specification.html#type-system">Type
369 system chapter of the D-Bus specification</ulink>). For simple
370 types each parameter following the signature should simply be the
371 parameter's value formatted as string. Positive boolean values may
372 be formatted as <literal>true</literal>, <literal>yes</literal>,
373 <literal>on</literal>, <literal>1</literal>; negative boolean
374 values may be specified as <literal>false</literal>,
375 <literal>no</literal>, <literal>off</literal>,
376 <literal>0</literal>. For arrays, a numeric argument for the
377 number of entries followed by the entries shall be specified. For
378 variants the signature of the contents shall be specified,
379 followed by the contents. For dictionaries and structs the
380 contents of them shall be directly specified.</para>
383 <programlisting>s jawoll</programlisting> is the formatting
384 of a single string <literal>jawoll</literal>.</para>
387 <programlisting>as 3 hello world foobar</programlisting>
388 is the formatting of a string array with three entries,
389 <literal>hello</literal>, <literal>world</literal> and
390 <literal>foobar</literal>.</para>
393 <programlisting>a{sv} 3 One s Eins Two u 2 Yes b true</programlisting>
394 is the formatting of a dictionary
395 array that maps strings to variants, consisting of three
396 entries. The string <literal>One</literal> is assigned the
397 string <literal>Eins</literal>. The string
398 <literal>Two</literal> is assigned the 32bit unsigned
399 integer 2. The string <literal>Yes</literal> is assigned a
400 positive boolean.</para>
402 <para>Note that the <command>call</command>,
403 <command>get-property</command>, <command>introspect</command>
404 commands will also generate output in this format for the returned
405 data. Since this format is sometimes too terse to be easily
406 understood, the <command>call</command> and
407 <command>get-property</command> commands may generate a more
408 verbose, multi-line output when passed the
409 <option>--verbose</option> option.</para>
413 <title>Examples</title>
416 <title>Write and Read a Property</title>
418 <para>The following two commands first write a property and then
419 read it back. The property is found on the
420 <literal>/org/freedesktop/systemd1</literal> object of the
421 <literal>org.freedesktop.systemd1</literal> service. The name of
422 the property is <literal>LogLevel</literal> on the
423 <literal>org.freedesktop.systemd1.Manager</literal>
424 interface. The property contains a single string:</para>
426 <programlisting># busctl set-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager LogLevel s debug
427 # busctl get-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager LogLevel
428 s "debug"</programlisting>
433 <title>Terse and Verbose Output</title>
435 <para>The following two commands read a property that contains
436 an array of strings, and first show it in terse format, followed
437 by verbose format:</para>
439 <programlisting>$ busctl get-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager Environment
440 as 2 "LANG=en_US.UTF-8" "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin"
441 $ busctl get-property --verbose org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager Environment
443 STRING "LANG=en_US.UTF-8";
444 STRING "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin";
449 <title>Invoking a Method</title>
451 <para>The following command invokes a the
452 <literal>StartUnit</literal> method on the
453 <literal>org.freedesktop.systemd1.Manager</literal>
455 <literal>/org/freedesktop/systemd1</literal> object
456 of the <literal>org.freedesktop.systemd1</literal>
457 service, and passes it two strings
458 <literal>cups.service</literal> and
459 <literal>replace</literal>. As result of the method
460 call a single object path parameter is received and
463 <programlisting># busctl call org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager StartUnit ss "cups.service" "replace"
464 o "/org/freedesktop/systemd1/job/42684"</programlisting>
469 <title>See Also</title>
472 <citerefentry><refentrytitle>dbus-daemon</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
473 <ulink url="http://freedesktop.org/wiki/Software/dbus">D-Bus</ulink>,
474 <ulink url="https://code.google.com/p/d-bus/">kdbus</ulink>,
475 <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
476 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
477 <citerefentry><refentrytitle>systemd-bus-proxyd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
478 <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
479 <citerefentry><refentrytitle>wireshark</refentrytitle><manvolnum>1</manvolnum></citerefentry>