Copyright	(c) 2016 Michael Walker
License	MIT
Maintainer	Michael Walker <[email protected]>
Stability	stable
Portability	portable
Safe Haskell	None
Language	Haskell2010

Control.Concurrent.Classy.QSemN

Contents

General Quantity Semaphores

Description

Quantity semaphores in which each thread may wait for an arbitrary "amount".

Synopsis

General Quantity Semaphores

data QSemN m Source #

QSemN is a quantity semaphore in which the resource is aqcuired and released in units of one. It provides guaranteed FIFO ordering for satisfying blocked waitQSemN calls.

The pattern

bracket_ (waitQSemN n) (signalQSemN n) (...)

is safe; it never loses any of the resource.

newQSemN :: MonadConc m => Int -> m (QSemN m) Source #

Build a new QSemN with a supplied initial quantity. The initial quantity must be at least 0.

waitQSemN :: MonadConc m => QSemN m -> Int -> m () Source #

Wait for the specified quantity to become available

signalQSemN :: MonadConc m => QSemN m -> Int -> m () Source #

Signal that a given quantity is now available from the QSemN.