On 15/09/2010 03:33, Edward Z. Yang wrote:
Excerpts from Simon Marlow's message of Mon Sep 13 05:10:13 -0400 2010:
The idea of having user-definable cancellation mechanisms seems quite sensible, given that we have so many ways to do this. However it seems quite hard in practice: for pthread_cancel, the RTS has to behave quite differently from pthread_kill. The API for defining the cancellation mechanism could get quite complicated.
For now I would go with 'interruptible' (meaning either pthread_kill() or CancelSynchronousIO()). It's not nearly as dangerous as pthread_cancel(), but it covers a lot of the cases we're interested in, and it doesn't have problems with bound threads.
Sounds good. I'll roll this change tomorrow. Maybe we should emit a warning pre-Vista that "interruptible" is not being honored?
It's not clear to me when to emit the warning: the system we're compiling on is not necessarily the one we're going to run on. This is more often the case for us where we're building distributions, than for other people though.
Also, it occurs to me that a lot of this functionality could be implemented in user space.
Maybe - feel free to propose something... Cheers, Simon