nsInputStreamReadyEvent *ev = (nsInputStreamReadyEvent *) plevent;
nsOutputStreamReadyEvent *ev = (nsOutputStreamReadyEvent *) plevent;
    PR_STATIC_CALLBACK(void *) EventHandler(PLEvent *plevent)    {        nsInputStreamReadyEvent *ev = (nsInputStreamReadyEvent *) plevent;        // bypass event delivery if this is a cleanup event...        if (ev->mCallback)            ev->mCallback->OnInputStreamReady(ev->mStream);        ev->mCallback = 0;        return NULL;    }