This is a Windows-specific bug. In fact all I/O on Windows in the threaded RTS is currently done with blocking foreign calls, so you won't be able to kill any threads blocked on I/O I'm afraid. In the non-threaded RTS you can kill the Haskell thread, but the I/O will still happen (actually I think this is worse than the -threaded behaviour).
Damn my lame platform! Well, that's a relief: at least I have an explanation as to why it works that way. I was wondering how I would gracefully kill something waiting for a socket accept. I assume that when the process exits, all threads (OS or Haskell) are terminated. So if I use the normal RTS, and have the main thread exit, any thread waiting on a socket accept will be terminated too. That seems to be my experience, anyway. I'd offer to help but I'm no Windows expert, and 1-2 days effort would be a few weeks elapsed time for me. Alistair ***************************************************************** Confidentiality Note: The information contained in this message, and any attachments, may contain confidential and/or privileged material. It is intended solely for the person(s) or entity to which it is addressed. Any review, retransmission, dissemination, or taking of any action in reliance upon this information by persons or entities other than the intended recipient(s) is prohibited. If you received this in error, please contact the sender and delete the material from any computer. *****************************************************************