dbus-monitor — debug probe to print message bus messages
dbus-monitor
[ --system | --session | --address ADDRESS
] [ --profile | --monitor | --pcap | --binary ] [ watch
expressions
]
The dbus-monitor command is used to monitor messages going through a D-Bus message bus. See https://www.freedesktop.org/wiki/Software/dbus/ for more information about the big picture.
There are two well-known message buses: the systemwide message bus (installed on many systems as the "messagebus" service) and the per-user-login-session message bus (started each time a user logs in). The --system and --session options direct dbus-monitor to monitor the system or session buses respectively. If neither is specified, dbus-monitor monitors the session bus.
dbus-monitor has two different text output modes: the 'classic'-style monitoring mode, and profiling mode. The profiling format is a compact format with a single line per message and microsecond-resolution timing information. The --profile and --monitor options select the profiling and monitoring output format respectively.
dbus-monitor also has two binary output modes.
The binary mode, selected by --binary
, outputs the
entire binary message stream (without the initial authentication handshake).
The PCAP mode, selected by --pcap
, adds a
PCAP file header to the beginning of the output, and prepends a PCAP
message header to each message; this produces a binary file that can
be read by, for instance, Wireshark.
If no mode is specified, dbus-monitor uses the monitoring output format.
In order to get dbus-monitor to see the messages you are interested in, you should specify a set of watch expressions as you would expect to be passed to the dbus_bus_add_match function.
The message bus configuration may keep dbus-monitor from seeing all messages, especially if you run the monitor as a non-root user.
--system
Monitor the system message bus.
--session
Monitor the session message bus. (This is the default.)
--address ADDRESS
Monitor an arbitrary message bus given at ADDRESS.
--profile
Use the profiling output format.
--monitor
Use the monitoring output format. (This is the default.)
Here is an example of using dbus-monitor to watch for the gnome typing monitor to say things
dbus-monitor "type='signal',sender='org.gnome.TypingMonitor',interface='org.gnome.TypingMonitor'"
dbus-monitor was written by Philip Blundell. The profiling output mode was added by Olli Salli.
Please send bug reports to the D-Bus mailing list or bug tracker, see https://www.freedesktop.org/wiki/Software/dbus/