internal void Free()
{
if (before_closure != null)
{
before_closure.Dispose();
}
if (after_closure != null)
{
after_closure.Dispose();
}
GC.SuppressFinalize(this);
}
static void NotifyCallback(IntPtr data, IntPtr raw_closure)
{
SignalClosure closure = closures [raw_closure] as SignalClosure;
if (closure != null)
{
closure.Dispose();
}
}