In message <20050930.115615.74743836.nagai / ai.kyutech.ac.jp>, Hidetoshi 
NAGAI <nagai / ai.kyutech.ac.jp> writes

Thank you for answer. Most helpful.

Stephen

>On Ruby/Tk, all operations and callbacks are evaluated on the
>eventloop thread. All calls are serialized to avoid conflict of
>GUI operation. Therefore, never wait or sleep on the callback
>operation!!

....
-- 
Stephen Kellett
Object Media Limited    http://www.objmedia.demon.co.uk/software.html
Computer Consultancy, Software Development
Windows C++, Java, Assembler, Performance Analysis, Troubleshooting