SIGIO lock.  This is generally possible through use of an

	SIGIO lock.  This is generally possible through use of an

	elevated reference count on the structure, such as reliance

	elevated reference count on the structure, such as reliance

	on a file descriptor reference to a pipe during a pipe

	on a file descriptor reference to a pipe during a pipe

    </sect2>

    </sect2>

    <sect2>

    <sect2>