limited suspending on readChan possible?

[Simon Marlow]

> Hello everyone, I thought I?d return to more earthly issue 
> than discovering
> bugs in signal handlers etc. :)
> 
> I?ve been looking for a way to suspend on an empty channel for only a
> limited time. So I came up with a solution which involves 
> dupChan (which
> is currently broken as stated in Meurig?s bug-report) and unGetChan:

How about 

	timeout N . readChan

where timeout is defined according to our Asynchronous Exceptions paper
(see http://www.haskell.org/~simonmar/papers/async.ps.gz).

Cheers,
	Simon