DBusConnection

Object Hierarchy:

GLib.DBusConnection GLib.DBusConnection GLib.DBusConnection GLib.Object GLib.Object GLib.Object->GLib.DBusConnection GLib.AsyncInitable GLib.AsyncInitable GLib.AsyncInitable->GLib.DBusConnection GLib.Initable GLib.Initable GLib.Initable->GLib.DBusConnection

Description:

[ CCode ( type_id = "g_dbus_connection_get_type ()" ) ]
[ Version ( since = "2.26" ) ]
public sealed class DBusConnection : Object, AsyncInitable, Initable

The `GDBusConnection` type is used for D-Bus connections to remote peers such as a message buses.

It is a low-level API that offers a lot of flexibility. For instance, it lets you establish a connection over any transport that can by represented as a [class@Gio.IOStream].

This class is rarely used directly in D-Bus clients. If you are writing a D-Bus client, it is often easier to use the [func@Gio.bus_own_name], [func@Gio.bus_watch_name] or [func@Gio.DBusProxy.new_for_bus] APIs.

As an exception to the usual GLib rule that a particular object must not be used by two threads at the same time, `GDBusConnection`s methods may be called from any thread. This is so that [func@Gio.bus_get] and [func@Gio.bus_get_sync] can safely return the same `GDBusConnection` when called from any thread.

Most of the ways to obtain a `GDBusConnection` automatically initialize it (i.e. connect to D-Bus): for instance, [func@Gio.DBusConnection.new] and [func@Gio.bus_get], and the synchronous versions of those methods, give you an initialized connection. Language bindings for GIO should use [func@Gio.Initable.new] or [func@Gio.AsyncInitable.new_async], which also initialize the connection.

If you construct an uninitialized `GDBusConnection`, such as via [ctor@GObject.Object.new], you must initialize it via [ method@Gio.Initable.init] or [method@Gio.AsyncInitable.init_async] before using its methods or properties. Calling methods or accessing properties on a `GDBusConnection` that has not completed initialization successfully is considered to be invalid, and leads to undefined behaviour. In particular, if initialization fails with a `GError`, the only valid thing you can do with that `GDBusConnection` is to free it with [method@GObject.Object.unref].

An example D-Bus server

Here is an example for a D-Bus server: gdbus-example-server.c

An example for exporting a subtree

Here is an example for exporting a subtree: gdbus-example-subtree.c

An example for file descriptor passing

Here is an example for passing UNIX file descriptors: gdbus-unix-fd-client.c

An example for exporting a GObject

Here is an example for exporting a Object: gdbus-example-export.c

Example: Using extra D-Bus hooks with a GLib.Application::

public class MyApplication : Application {
	private MyApplication () {
		Object (application_id: "org.example.application", flags: 0);
		set_inactivity_timeout (10000);
	}

	public override void activate () {
		// NOTE: when doing a longer-lasting action here that returns
		//  to the mainloop, you should use g_application_hold() and
		//  g_application_release() to keep the application alive until
		//  the action is completed.
		print ("Activated\n");
	}

	public override bool dbus_register (DBusConnection connection, string object_path) throws Error {
		// We must chain up to the parent class:
		base.dbus_register (connection, object_path);

		// Now we can do our own stuff here. For example, we could export some D-Bus objects
		return true;
	}

	public override void dbus_unregister (DBusConnection connection, string object_path) {
		// Do our own stuff here, e.g. unexport any D-Bus objects we exported in the dbus_register
		//  hook above. Be sure to check that we actually did export them, since the hook
		//  above might have returned early due to the parent class' hook returning false!

		base.dbus_unregister (connection, object_path);
	}

	public static int main (string[] args) {
		MyApplication app = new MyApplication ();
		int status = app.run (args);
		return status;
	}
}

valac --pkg gio-2.0 GLib.Application.3.vala


Namespace: GLib
Package: gio-2.0

Content:

Properties:

Static methods:

Creation methods:

Methods:

Signals:

  • public signal void on_closed (bool remote_peer_vanished, Error? error)
    Emitted when the connection is closed.

Inherited Members:

All known members inherited from class GLib.Object
All known members inherited from interface GLib.AsyncInitable
All known members inherited from interface GLib.Initable