DBus is a module that integrate dbus into Fcitx main loop. The only exposed function is get connection, which you should use this shared connection for Fcitx.
Fcitx's service name is "org.fcitx.Fcitx-<display number>", the display number should be fetched by fcitx_utils_get_display_number, even there is no X server running, for example under TTY.
If you need something related to DBus, please use Inter Module Function Call to talk with this module.
Here is the exposed function definition of X11, you can also find it in include/fcitx/module/dbus/dbusstuff.h
#define FCITX_DBUS_NAME "fcitx-dbus" #define FCITX_DBUS_GETCONNECTION 0 #define FCITX_DBUS_GETCONNECTION_RETURNTYPE DBusConnection*