forkIO implemenation

Derek Elkins ddarius at
Fri Oct 17 00:15:17 EDT 2003

On Thu, 16 Oct 2003 21:31:26 -0400
"Feingold, Jason (WingspanTech)" <jfeing at> wrote:

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> I infer from a discussion from March 2002 that concurrency in Haskell
> is not implemented in native threads, at least in Windows.  Is this
> true? 

Yes, for at least Hugs and GHC, for the most part.

> The reason I ask is that when I forkIO and accept from a socket in the
> new thread everything seems blocked.  Is this the expected behavior? 

Depends on what implementation and version you are using (which you
didn't mention). I assume you are using GHC5, in which case the Windows
socket binding is blocking. This is apparently fixed in GHC6.

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