dbus-launch

TLDR

Start a D-Bus session bus

$ dbus-launch

Start session and export environment variables

$ eval $(dbus-launch --sh-syntax)

Start with auto-launch option

$ dbus-launch --autolaunch=[machine-id]

Start a specific program with D-Bus

$ dbus-launch [program] [arguments]

Exit when program terminates

$ dbus-launch --exit-with-session [program]

Close bus when X session ends

$ dbus-launch --exit-with-x11

SYNOPSIS

dbus-launch [options] [program] [args]

dbus-launch starts a session instance of the D-Bus message bus daemon and provides the connection address to client applications. It's typically used to ensure a D-Bus session is available for desktop applications.
When invoked without arguments, it prints environment variables (DBUSSESSIONBUSADDRESS and DBUSSESSIONBUSPID) that clients need to connect. With shell syntax options, the output can be directly evaluated to set these variables.
When a program is specified, dbus-launch starts the D-Bus daemon, sets up the environment, and then executes the program. The --exit-with-session flag ensures the daemon terminates when the program exits.

PARAMETERS

PROGRAM

Program to run with the D-Bus session.

--sh-syntax

Output Bourne shell compatible syntax.

--csh-syntax

Output C shell compatible syntax.

--autolaunch MACHINEID

Enable autolaunch with specified machine ID.

--exit-with-session

Exit when launched program terminates.

--exit-with-x11

Exit when X11 connection closes.

--config-file FILE

Use specified configuration file.

--help

Display help information.

CAVEATS

Multiple invocations without proper session management can start multiple daemons. The daemon must be properly terminated to avoid resource leaks. X11 integration requires an active display connection.

HISTORY

dbus-launch is part of the D-Bus reference implementation, created by Red Hat and the freedesktop.org project around 2003. It became essential infrastructure for Linux desktop environments requiring inter-process communication.