c_g_dbus_proxy_call_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)
GVariant* function(GDBusProxy* proxy, const(char)* methodName, GVariant* parameters, GDBusCallFlags flags, int timeoutMsec, GCancellable* cancellable, GError** err) c_g_dbus_proxy_call_sync;

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