On implementing semaphores with sets

Solutions Based on Binary Semaphores

A graphical form of the mutual exclusion problem is considered in which each vertex represents a process and each edge represents a mutual exclusion constraint between the critical sections of the processes associated with its endpoints. An edge semaphore solution for mutual exclusion problems is defined, and those graphs which are edge solvable are characterized in terms of both a forbidden su...

Implementing Fudgets with Standard Widget Sets

Carlsson and Hallgren 1] describe the implementation of a set of \functional widgets" (Fudgets): components for programming graphical user interfaces under the X window system using the non-strict functional programming language Haskell. We describe an alternative implementation based on existing widget sets (currently Openlook and Motif). Our purpose is twofold: to show that the Fudgets approa...

Strengthen, Widen, Get Semaphores

Many parallel programs are expressed in terms of conditional atomic actions with different degrees of atomicity. It is known that these synchronization primitives are expensive to implement in its fully generality [2]. Many platforms provide an efficient set of synchronization primitives. Semaphores are a very special case of conditional atomic actions which can be considered a canonical synchr...

Implementing Sets for Reversible Computation

Sets provide a very general tool for representing information and modelling the behaviour of systems. We consider their implementation and associated problems of garbage collection in the context of reversible computation. We describe our implementation technique, which uses ordered arrays, and discuss scalability of performance.

Monitors and Semaphores