c_g_dbus_connection_send_message_with_reply_sync

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
GDBusMessage* function(GDBusConnection* connection, GDBusMessage* message, GDBusSendMessageFlags flags, int timeoutMsec, uint* outSerial, GCancellable* cancellable, GError** err) c_g_dbus_connection_send_message_with_reply_sync;

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