[Haskell-cafe] Broadcast signals between threads

[Joachim Breitner]

Hi,

Am Sonntag, den 27.05.2007, 14:07 +0400 schrieb Bulat Ziganshin:
> Hello Joachim,
> 
> Friday, May 25, 2007, 9:57:45 PM, you wrote:
> 
> > I’m writing a TCP server app ATM. It has one thread per client. Some of
> > the clients want to be notified if the internal state changes, while
> > others are happily chatting with the server, possible modifying the
> > internal state. What I need now is a way for the chatting thread to
> > signal “anyone interested” that the state has changed.
> 
> i don't read your letter carefully but at least there is throwTo
> function what implement exactly what you said in subj. look
> Control.Exception module docs and read "awkward squad" paper:
> 
> "Tackling the awkward squad: monadic input/output, concurrency,
> exceptions, and foreign-language calls in Haskell"
> http://research.microsoft.com/Users/simonpj/papers/marktoberdorf/marktoberdorf.ps.gz

I don’t like throwTo because then I need to keep track of which threads
are currently interested in the signal, to not accidentally throw an
exception to a thread that does not expect it. Just seems too dangerous
to me :-)

Greetings,
Joachim

-- 
Joachim Breitner
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