I try to schedule musical events and this shall happen quite accurately. I found 'usleep' which is limited to Posix and I cannot interrupt with Ctrl-C if IO actions are scheduled using this function. Then I found 'threadDelay' which can be interrupted, but it is stated that its resolution is 1/50 seconds, which is too coarse. Additionally I found that it liberally rounds the waiting time up to the next multiple of 1/50 second. Even 'threadDelay 0' waits some time. This might be due to the fact that threadDelay was not intended for such applications, but it shall wait at least the time specified: http://www.haskell.org/pipermail/glasgow-haskell-users/2004-January/006148.h... My question: Is there some more accurate time scheduling available? Maybe not only a more accurate 'wait' function but a function which processes a list of events and starts the actions at the appropriate time points. When I write do action0 threadDelay t action1 then action1 is not started duration t after action0 is started, but time t after action0 is finished. This should be avoided by a sophisticated scheduling function. This is how I currently employ threadDelay: http://cvs.haskell.org/darcs/haskore/src/Haskore/Basic/Schedule.lhs