Cancel read on socket

[leonp at plris.com (Leon Pollak)]

Hello, all.

Is there any way to cancel currently waiting read operation on UDP socket?
I do not want to close it (need to use it immediately) or use select() 
(consumes a lot of CPU time).

I looked into the select() implementation in rtems_select(...) and feels that 
this must not be too complicated...

Thanks ahead. 
-- 
Leon