DEFINITION MODULE Lock ; (* Author : Gaius Mulley Title : Lock Date : 12/2/86 Version : 1.0 Last Edit : 22/7/86 Description: Lock - Implements a Read / Write Lock *) EXPORT QUALIFIED LOCK, GetReadAccess, ReleaseReadAccess, GetWriteAccess, ReleaseWriteAccess, InitLock ; TYPE LOCK ; PROCEDURE GetReadAccess (l: LOCK) ; PROCEDURE ReleaseReadAccess (l: LOCK) ; PROCEDURE GetWriteAccess (l: LOCK) ; PROCEDURE ReleaseWriteAccess (l: LOCK) ; PROCEDURE InitLock (Name: ARRAY OF CHAR) : LOCK ; END Lock.