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
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
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>--size=</option></term>
130 <para>When used with the <command>capture</command> command
131 specifies the maximum bus message size to capture
132 ("snaplen"). Defaults to 4096 bytes.</para>
137 <term><option>--list</option></term>
140 <para>When used with the <command>tree</command> command shows a
141 flat list of object paths instead of a tree.</para>
146 <term><option>--quiet</option></term>
149 <para>When used with the <command>call</command> command
150 suppresses display of the response message payload. Note that even
151 if this option is specified errors returned will still be
152 printed and the tool will indicate success or failure with
153 the process exit code.</para>
158 <term><option>--verbose</option></term>
161 <para>When used with the <command>call</command> or
162 <command>get-property</command> command shows output in a
163 more verbose format.</para>
168 <term><option>--expect-reply=</option><replaceable>BOOL</replaceable></term>
171 <para>When used with the <command>call</command> command
172 specifies whether <command>busctl</command> shall wait for
173 completion of the method call, output the returned method
174 response data, and return success or failure via the process
175 exit code. If this is set to <literal>no</literal> the
176 method call will be issued but no response is expected, the
177 tool terminates immediately, and thus no response can be
178 shown, and no success or failure is returned via the exit
179 code. To only suppress output of the reply message payload
180 use <option>--quiet</option> above. Defaults to
181 <literal>yes</literal>.</para>
186 <term><option>--auto-start=</option><replaceable>BOOL</replaceable></term>
189 <para>When used with the <command>call</command> command specifies
190 whether the method call should implicitly activate the
191 called service should it not be running yet but is
192 configured to be auto-started. Defaults to
193 <literal>yes</literal>.</para>
198 <term><option>--allow-interactive-authorization=</option><replaceable>BOOL</replaceable></term>
201 <para>When used with the <command>call</command> command
202 specifies whether the services may enforce interactive
203 authorization while executing the operation, if the security
204 policy is configured for this. Defaults to
205 <literal>yes</literal>.</para>
210 <term><option>--timeout=</option><replaceable>SECS</replaceable></term>
213 <para>When used with the <command>call</command> command
214 specifies the maximum time to wait for method call
215 completion. If no time unit is specified assumes
216 seconds. The usual other units are understood, too (ms, us,
217 s, min, h, d, w, month, y). Note that this timeout does not
218 apply if <option>--expect-reply=no</option> is used as the
219 tool does not wait for any reply message then. When not
220 specified or when set to 0 the default of
221 <literal>25s</literal> is assumed.</para>
226 <term><option>--augment-creds=</option><replaceable>BOOL</replaceable></term>
229 <para>Controls whether credential data reported by
230 <command>list</command> or <command>status</command> shall
231 be augmented with data from
232 <filename>/proc</filename>. When this is turned on the data
233 shown is possibly inconsistent, as the data read from
234 <filename>/proc</filename> might be more recent than rest of
235 the credential information. Defaults to <literal>yes</literal>.</para>
239 <xi:include href="user-system-options.xml" xpointer="user" />
240 <xi:include href="user-system-options.xml" xpointer="system" />
241 <xi:include href="user-system-options.xml" xpointer="host" />
242 <xi:include href="user-system-options.xml" xpointer="machine" />
244 <xi:include href="standard-options.xml" xpointer="no-pager" />
245 <xi:include href="standard-options.xml" xpointer="no-legend" />
246 <xi:include href="standard-options.xml" xpointer="help" />
247 <xi:include href="standard-options.xml" xpointer="version" />
252 <title>Commands</title>
254 <para>The following commands are understood:</para>
258 <term><command>list</command></term>
260 <listitem><para>Show service names on the bus. This is the
261 default if no command is specified.</para></listitem>
265 <term><command>status</command> <arg choice="opt"><replaceable>SERVICE</replaceable></arg></term>
267 <listitem><para>Show process information and credentials of a
268 bus service (if one is specified by its unique or well-known
269 name), a process (if one is specified by its numeric PID), or
270 the owner of the bus (if no parameter is
271 specified).</para></listitem>
275 <term><command>monitor</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
277 <listitem><para>Dump messages being exchanged. If
278 <replaceable>SERVICE</replaceable> is specified, show messages
279 to or from this endpoint. Otherwise, show all messages on the
280 bus. Use Ctrl-C to terminate dump.</para></listitem>
284 <term><command>capture</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
286 <listitem><para>Similar to <command>monitor</command> but
287 writes the output in pcap format (for details see the <ulink
288 url="http://wiki.wireshark.org/Development/LibpcapFileFormat">Libpcap
289 File Format</ulink> description. Make sure to redirect the
290 output to STDOUT to a file. Tools like
291 <citerefentry project='die-net'><refentrytitle>wireshark</refentrytitle><manvolnum>1</manvolnum></citerefentry>
292 may be used to dissect and view the generated
293 files.</para></listitem>
297 <term><command>tree</command> <arg choice="opt" rep="repeat"><replaceable>SERVICE</replaceable></arg></term>
299 <listitem><para>Shows an object tree of one or more
300 services. If <replaceable>SERVICE</replaceable> is specified,
301 show object tree of the specified services only. Otherwise,
302 show all object trees of all services on the bus that acquired
303 at least one well-known name.</para></listitem>
307 <term><command>introspect</command> <arg choice="plain"><replaceable>SERVICE</replaceable></arg> <arg choice="plain"><replaceable>OBJECT</replaceable></arg> <arg choice="opt"><replaceable>INTERFACE</replaceable></arg></term>
309 <listitem><para>Show interfaces, methods, properties and
310 signals of the specified object (identified by its path) on
311 the specified service. If the interface argument is passed the
312 output is limited to members of the specified
313 interface.</para></listitem>
317 <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>
319 <listitem><para>Invoke a method and show the response. Takes a
320 service name, object path, interface name and method name. If
321 parameters shall be passed to the method call a signature
322 string is required, followed by the arguments, individually
323 formatted as strings. For details on the formatting used, see
324 below. To suppress output of the returned data use the
325 <option>--quiet</option> option.</para></listitem>
329 <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>
331 <listitem><para>Retrieve the current value of one or more
332 object properties. Takes a service name, object path,
333 interface name and property name. Multiple properties may be
334 specified at once in which case their values will be shown one
335 after the other, separated by newlines. The output is by
336 default in terse format. Use <option>--verbose</option> for a
337 more elaborate output format.</para></listitem>
341 <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>
343 <listitem><para>Set the current value an object
344 property. Takes a service name, object path, interface name,
345 property name, property signature, followed by a list of
346 parameters formatted as strings.</para></listitem>
350 <term><command>help</command></term>
352 <listitem><para>Show command syntax help.</para></listitem>
358 <title>Parameter Formatting</title>
360 <para>The <command>call</command> and
361 <command>set-property</command> commands take a signature string
362 followed by a list of parameters formatted as string (for details
363 on D-Bus signature strings see the <ulink
364 url="http://dbus.freedesktop.org/doc/dbus-specification.html#type-system">Type
365 system chapter of the D-Bus specification</ulink>). For simple
366 types each parameter following the signature should simply be the
367 parameter's value formatted as string. Positive boolean values may
368 be formatted as <literal>true</literal>, <literal>yes</literal>,
369 <literal>on</literal>, <literal>1</literal>; negative boolean
370 values may be specified as <literal>false</literal>,
371 <literal>no</literal>, <literal>off</literal>,
372 <literal>0</literal>. For arrays, a numeric argument for the
373 number of entries followed by the entries shall be specified. For
374 variants the signature of the contents shall be specified,
375 followed by the contents. For dictionaries and structs the
376 contents of them shall be directly specified.</para>
379 <programlisting>s jawoll</programlisting> is the formatting
380 of a single string <literal>jawoll</literal>.</para>
383 <programlisting>as 3 hello world foobar</programlisting>
384 is the formatting of a string array with three entries,
385 <literal>hello</literal>, <literal>world</literal> and
386 <literal>foobar</literal>.</para>
389 <programlisting>a{sv} 3 One s Eins Two u 2 Yes b true</programlisting>
390 is the formatting of a dictionary
391 array that maps strings to variants, consisting of three
392 entries. The string <literal>One</literal> is assigned the
393 string <literal>Eins</literal>. The string
394 <literal>Two</literal> is assigned the 32bit unsigned
395 integer 2. The string <literal>Yes</literal> is assigned a
396 positive boolean.</para>
398 <para>Note that the <command>call</command>,
399 <command>get-property</command>, <command>introspect</command>
400 commands will also generate output in this format for the returned
401 data. Since this format is sometimes too terse to be easily
402 understood, the <command>call</command> and
403 <command>get-property</command> commands may generate a more
404 verbose, multi-line output when passed the
405 <option>--verbose</option> option.</para>
409 <title>Examples</title>
412 <title>Write and Read a Property</title>
414 <para>The following two commands first write a property and then
415 read it back. The property is found on the
416 <literal>/org/freedesktop/systemd1</literal> object of the
417 <literal>org.freedesktop.systemd1</literal> service. The name of
418 the property is <literal>LogLevel</literal> on the
419 <literal>org.freedesktop.systemd1.Manager</literal>
420 interface. The property contains a single string:</para>
422 <programlisting># busctl set-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager LogLevel s debug
423 # busctl get-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager LogLevel
424 s "debug"</programlisting>
429 <title>Terse and Verbose Output</title>
431 <para>The following two commands read a property that contains
432 an array of strings, and first show it in terse format, followed
433 by verbose format:</para>
435 <programlisting>$ busctl get-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager Environment
436 as 2 "LANG=en_US.UTF-8" "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin"
437 $ busctl get-property --verbose org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager Environment
439 STRING "LANG=en_US.UTF-8";
440 STRING "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin";
445 <title>Invoking a Method</title>
447 <para>The following command invokes a the
448 <literal>StartUnit</literal> method on the
449 <literal>org.freedesktop.systemd1.Manager</literal>
451 <literal>/org/freedesktop/systemd1</literal> object
452 of the <literal>org.freedesktop.systemd1</literal>
453 service, and passes it two strings
454 <literal>cups.service</literal> and
455 <literal>replace</literal>. As result of the method
456 call a single object path parameter is received and
459 <programlisting># busctl call org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager StartUnit ss "cups.service" "replace"
460 o "/org/freedesktop/systemd1/job/42684"</programlisting>
465 <title>See Also</title>
468 <citerefentry project='dbus'><refentrytitle>dbus-daemon</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
469 <ulink url="http://freedesktop.org/wiki/Software/dbus">D-Bus</ulink>,
470 <ulink url="https://code.google.com/p/d-bus/">kdbus</ulink>,
471 <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
472 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
473 <citerefentry><refentrytitle>systemd-bus-proxyd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
474 <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
475 <citerefentry project='die-net'><refentrytitle>wireshark</refentrytitle><manvolnum>1</manvolnum></citerefentry>