gdbus - Tool for working with D-Bus objects
gdbus introspect [--system | --session | --address address]
--dest bus_name --object-path /path/to/object [--xml] [--recurse]
[--only-properties]
gdbus monitor [--system | --session | --address address]
--dest bus_name [--object-path /path/to/object]
gdbus call [--system | --session | --address address] --dest bus_name
--object-path /path/to/object
--method org.project.InterfaceName.MethodName [--timeout seconds]
ARG1 ARG2...
gdbus emit [--system | --session | --address address]
--object-path /path/to/object
--signal org.project.InterfaceName.SignalName
[--dest unique_bus_name] ARG1 ARG2...
gdbus help
gdbus is a simple tool for working with D-Bus objects.
introspect
Prints out interfaces and property values for a remote object. For
this to work, the owner of the object needs to implement the
org.freedesktop.DBus.Introspectable interface. If the --xml option
is used, the returned introspection XML is printed, otherwise a
parsed pretty representation is printed. The --recurse option can
be used to introspect children (and their children and so on) and
the --only-properties option can be used to only print the
interfaces with properties.
monitor
Monitors one or all objects owned by the owner of bus_name.
call
Invokes a method on a remote object. Each argument to pass to the
method must be specified as a serialized GVariant except that
strings do not need explicit quotes. The return values are printed
out as serialized GVariant values.
emit
Emits a signal. Each argument to include in the signal must be
specified as a serialized GVariant except that strings do not need
explicit quotes.
help
Prints help and exit.
gdbus ships with a bash completion script to complete commands, destinations, bus names, object paths and interface/method names.
This shows how to introspect an object - note that the value of each
property is displayed:
$ gdbus introspect --system \
--dest org.freedesktop.NetworkManager \
--object-path /org/freedesktop/NetworkManager/Devices/0
node /org/freedesktop/NetworkManager/Devices/0 {
interface org.freedesktop.DBus.Introspectable {
methods:
Introspect(out s data);
};
interface org.freedesktop.DBus.Properties {
methods:
Get(in s interface,
in s propname,
out v value);
Set(in s interface,
in s propname,
in v value);
GetAll(in s interface,
out a{sv} props);
};
interface org.freedesktop.NetworkManager.Device.Wired {
signals:
PropertiesChanged(a{sv} arg_0);
properties:
readonly b Carrier = false;
readonly u Speed = 0;
readonly s HwAddress = '00:1D:72:88:BE:97';
};
interface org.freedesktop.NetworkManager.Device {
methods:
Disconnect();
signals:
StateChanged(u arg_0,
u arg_1,
u arg_2);
properties:
readonly u DeviceType = 1;
readonly b Managed = true;
readwrite o Ip6Config = '/';
readwrite o Dhcp4Config = '/';
readwrite o Ip4Config = '/';
readonly u State = 2;
readwrite u Ip4Address = 0;
readonly u Capabilities = 3;
readonly s Driver = 'e1000e';
readwrite s Interface = 'eth0';
readonly s Udi = '/sys/devices/pci0000:00/0000:00:19.0/net/eth0';
};
};
The --recurse and --only-properties options can be useful when wanting
to inspect all objects owned by a particular process:
$ gdbus introspect --system --dest org.freedesktop.UPower --object-path / --recurse --only-properties
node / {
node /org {
node /org/freedesktop {
node /org/freedesktop/UPower {
interface org.freedesktop.UPower {
properties:
readonly b IsDocked = true;
readonly b LidForceSleep = false;
readonly b LidIsPresent = false;
readonly b LidIsClosed = false;
readonly b OnLowBattery = false;
readonly b OnBattery = false;
readonly b CanHibernate = true;
readonly b CanSuspend = true;
readonly s DaemonVersion = '0.9.10';
};
node /org/freedesktop/UPower/Policy {
};
node /org/freedesktop/UPower/Wakeups {
interface org.freedesktop.UPower.Wakeups {
properties:
readonly b HasCapability = true;
};
};
};
};
};
};
In a similar fashion, the introspect command can be used to learn
details about the Notify method:
[...]
interface org.freedesktop.Notifications {
methods:
GetServerInformation(out s return_name,
out s return_vendor,
out s return_version,
out s return_spec_version);
GetCapabilities(out as return_caps);
CloseNotification(in u id);
Notify(in s app_name,
in u id,
in s icon,
in s summary,
in s body,
in as actions,
in a{sv} hints,
in i timeout,
out u return_id);
};
[...]
With this information, it's easy to use the call command to display a
notification
$ gdbus call --session \
--dest org.freedesktop.Notifications \
--object-path /org/freedesktop/Notifications \
--method org.freedesktop.Notifications.Notify \
my_app_name \
42 \
gtk-dialog-info \
"The Summary" \
"Here's the body of the notification" \
[] \
{} \
5000
(uint32 12,)
Monitoring all objects on a service:
$ gdbus monitor --system --dest org.freedesktop.ConsoleKit
Monitoring signals from all objects owned by org.freedesktop.ConsoleKit
The name org.freedesktop.ConsoleKit is owned by :1.15
/org/freedesktop/ConsoleKit/Session2: org.freedesktop.ConsoleKit.Session.ActiveChanged (false,)
/org/freedesktop/ConsoleKit/Seat1: org.freedesktop.ConsoleKit.Seat.ActiveSessionChanged ('',)
/org/freedesktop/ConsoleKit/Session2: org.freedesktop.ConsoleKit.Session.ActiveChanged (true,)
/org/freedesktop/ConsoleKit/Seat1: org.freedesktop.ConsoleKit.Seat.ActiveSessionChanged ('/org/freedesktop/ConsoleKit/Session2',)
Monitoring a single object on a service:
$ gdbus monitor --system --dest org.freedesktop.NetworkManager --object-path /org/freedesktop/NetworkManager/AccessPoint/4141
Monitoring signals on object /org/freedesktop/NetworkManager/AccessPoint/4141 owned by org.freedesktop.NetworkManager
The name org.freedesktop.NetworkManager is owned by :1.5
/org/freedesktop/NetworkManager/AccessPoint/4141: org.freedesktop.NetworkManager.AccessPoint.PropertiesChanged ({'Strength': <byte 0x5c>},)
/org/freedesktop/NetworkManager/AccessPoint/4141: org.freedesktop.NetworkManager.AccessPoint.PropertiesChanged ({'Strength': <byte 0x64>},)
/org/freedesktop/NetworkManager/AccessPoint/4141: org.freedesktop.NetworkManager.AccessPoint.PropertiesChanged ({'Strength': <byte 0x5e>},)
/org/freedesktop/NetworkManager/AccessPoint/4141: org.freedesktop.NetworkManager.AccessPoint.PropertiesChanged ({'Strength': <byte 0x64>},)
Emitting a signal:
$ gdbus emit --session --object-path /foo --signal org.bar.Foo "['foo', 'bar', 'baz']"
Emitting a signal to a specific process:
$ gdbus emit --session --object-path /bar --signal org.bar.Bar someString --dest :1.42
Please send bug reports to either the distribution bug tracker or the upstream bug tracker at https://bugzilla.gnome.org/enter_bug.cgi?product=glib.
dbus-send(1)
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