|Maintainer||Bas van Dijk <email@example.com> , Roel van Dijk <firstname.lastname@example.org>|
An Event is a simple mechanism for communication between threads: one thread signals an event and other threads wait for it.
Each event has an internal state which is either "Set" or "Cleared". This
state can be changed with the corresponding functions
wait function blocks until the state is "Set". An important property of
setting an event is that all threads waiting for it are woken.
It was inspired by the Python
Event object. See:
This module is designed to be imported qualified. We suggest importing it like:
import Control.Concurrent.Event ( Event ) import qualified Control.Concurrent.Event as Event ( ... )
An event is in one of two possible states: "Set" or "Cleared".
Block until the event is
set or until a timer expires.
The timeout is specified in microseconds. A timeout of 0 μs will cause the
function to return
False without blocking in case the event state is
"Cleared". Negative timeouts are treated the same as a timeout of 0 μs.
Changes the state of the event to "Set". All threads that where waiting
for this event are woken. Threads that
wait after the state is changed to
"Set" will not block at all.
Changes the state of the event to "Cleared". Threads that
wait after the
state is changed to "Cleared" will block until the state is changed to "Set".