Read lock and write lock management system based upon mutex and semaphore availability

摘要

A method and apparatus for implementing a read/write lock mechanism in software. In an operating environment that allows objects such threads to wait on a plurality of synchronization objects simultaneously, a read/write lock can be implemented using two synchronization objects such as a mutex and a semaphore. Further, a variable is introduced to track the number of reader threads awaiting to read protected data. The read/write lock permits a plurality of reader threads to access protected data simultaneously, while only allowing a single writer thread access to a protected data location.