NAME
busctl - Introspect the bus
SYNOPSIS
busctl [OPTIONS...] [COMMAND] [NAME...]
DESCRIPTION
busctl may be used to introspect and monitor the D-Bus bus.
COMMANDS
The following commands are understood:
list
Added in version 209.
status [SERVICE]
Added in version 209.
monitor [SERVICE...]
Added in version 209.
capture [SERVICE...]
Added in version 218.
tree [SERVICE...]
Added in version 218.
introspectSERVICEOBJECT [INTERFACE]
Added in version 218.
callSERVICEOBJECTINTERFACEMETHOD [SIGNATURE [ARGUMENT...]]
Added in version 218.
emitOBJECTINTERFACESIGNAL [SIGNATURE [ARGUMENT...]]
Added in version 242.
wait [SERVICE] OBJECTINTERFACESIGNAL
Added in version 257.
get-propertySERVICEOBJECTINTERFACEPROPERTY...
Added in version 218.
set-propertySERVICEOBJECTINTERFACEPROPERTYSIGNATUREARGUMENT...
Added in version 218.
help
Added in version 209.
OPTIONS
The following options are understood:
--address=ADDRESS
Added in version 209.
--show-machine
Added in version 209.
--unique
Added in version 209.
--acquired
Added in version 209.
--activatable
Added in version 209.
--match=MATCH
Added in version 209.
--size=
Added in version 218.
--list
Added in version 218.
-q, --quiet
Added in version 218.
--verbose
Added in version 218.
--xml-interface
Added in version 243.
--expect-reply=BOOL
Added in version 218.
--auto-start=BOOL
Added in version 218.
--allow-interactive-authorization=BOOL
Added in version 218.
--timeout=SECS
Added in version 218.
--limit-messages=NUMBER, -NNUMBER
Added in version 257.
--augment-creds=BOOL
Added in version 218.
--watch-bind=BOOL
Added in version 237.
--destination=SERVICE
Added in version 242.
--user
--system
-H, --host=
-M, --machine=
-C, --capsule=
Added in version 256.
-l, --full
Added in version 245.
--json=MODE
-j
--no-pager
--no-legend
-h, --help
--version
PARAMETER FORMATTING
The call and set-property commands take a signature string followed by a list of parameters formatted as string (for details on D-Bus signature strings, see the Type system chapter of the D-Bus specification[2]). For simple types, each parameter following the signature should simply be the parameter's value formatted as string. Positive boolean values may be formatted as "true", "yes", "on", or "1"; negative boolean values may be specified as "false", "no", "off", or "0". For arrays, a numeric argument for the number of entries followed by the entries shall be specified. For variants, the signature of the contents shall be specified, followed by the contents. For dictionaries and structs, the contents of them shall be directly specified.
For example,
s jawollis the formatting of a single string "jawoll".
as 3 hello world foobaris the formatting of a string array with three entries, "hello", "world" and "foobar".
a{sv} 3 One s Eins Two u 2 Yes b trueis the formatting of a dictionary array that maps strings to variants, consisting of three entries. The string "One" is assigned the string "Eins". The string "Two" is assigned the 32-bit unsigned integer 2. The string "Yes" is assigned a positive boolean.
Note that the call, get-property, introspect commands will also generate output in this format for the returned data. Since this format is sometimes too terse to be easily understood, the call and get-property commands may generate a more verbose, multi-line output when passed the --verbose option.
EXAMPLES
Example 1. Write and Read a Property
The following two commands first write a property and then read it back. The property is found on the "/org/freedesktop/systemd1" object of the "org.freedesktop.systemd1" service. The name of the property is "LogLevel" on the "org.freedesktop.systemd1.Manager" interface. The property contains a single string:
# busctl set-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager LogLevel s debug
# busctl get-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager LogLevel
s "debug"Example 2. Terse and Verbose Output
The following two commands read a property that contains an array of strings, and first show it in terse format, followed by verbose format:
$ busctl get-property org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager Environment
as 2 "LANG=en_US.UTF-8" "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin"
$ busctl get-property --verbose org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager Environment
ARRAY "s" {
\n
STRING "LANG=en_US.UTF-8";
\n
STRING "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin";
};Example 3. Invoking a Method
The following command invokes the "StartUnit" method on the "org.freedesktop.systemd1.Manager" interface of the "/org/freedesktop/systemd1" object of the "org.freedesktop.systemd1" service, and passes it two strings "cups.service" and "replace". As a result of the method call, a single object path parameter is received and shown:
# busctl call org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager StartUnit ss "cups.service" "replace"
o "/org/freedesktop/systemd1/job/42684"SEE ALSO
dbus-daemon(1), D-Bus[3], sd-bus(3), varlinkctl(1), systemd(1), machinectl(1), wireshark(1)
NOTES
- 1.
PCAP Next Generation (pcapng) Capture File Format
- 2.
Type system chapter of the D-Bus specification
- 3.
D-Bus