dbus_bus_get VS dbus_connection_open
hp at redhat.com
Tue Sep 5 06:48:27 PDT 2006
frederic heem wrote:
>> The bus is only one possible remote process; you can also just open a
>> connection to some random app, if you like. dbus_bus_get pretty much
>> _is_ dbus_connection_open + dbus_bus_register.
> No difference shall be be made between a standard bus such as the system and
> sesssion bus (dbus_bus_get()), and a user defined bus
> (dbus_connection_open()). They are both factory function that returns
> a "ready to use" connection, only the key to get the connection changes, a
> number or a string. The dbus-send and dbus-monitor clearly shows that at the
> moment, the code has to make an extra check if the bus is a user defined bus,
> this is not symmetrical and very error prone.
> Moreover, for the glib binding, dbus_g_register() doesn't exist,
> dbus_register() is not documented and anyway shall not be use in glib code
> because it would break encapsulation.
> Let's rename dbus_connection_open() to dbus_connection_create() and add
> dbus_connection_open() that does dbus_connection_create() + dbus_register().
The issue here is not a user-defined bus; user-defined buses work the
same as the regular bus, except dbus_bus_get() doesn't know how to get
The issue is that you can connect to things that are not a bus at all.
That's what dbus_connection_open is generally for. The bus protocol is
built on a more general non-bus-specific protocol. The stuff in
dbus-bus.h knows about buses, but the stuff in dbus-connection.h does not.
dbus_g_register doesn't exist because the glib bindings aren't really
particularly finished, and the idea would be to have a DBusGProxy for
the org.freedesktop.DBus object I suppose.
>> - rather than == FALSE should use !
> Is it a real mistake or just synthetic sugar ?
Just a style thing
>> - I believe the code crashes if --address has no '=' after it?
> Yes, there is a mistake. But the why a standard function to parse parameter is
> not used ? get_opt() ?
getopt_long unfortunately isn't portable.
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