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User-Level Shared Variables (In a Hierarchical Control Environment)
Published
Author(s)
Don E. Libes
Abstract
We have implemented a shared variable system for UNIX 4.2BSD that emulates a shared or common memory. This system is all user level code and requires no kernel modifications. It is accessible from a variety of languages. This shared memory system provides its service transparently to remote hosts across a local-area network. This system is being used in a real application--an automated factory. Shared variables are an appropriate communication paradigm in a real-time environment (in comparison to message passing or pipes).
Libes, D.
(1985),
User-Level Shared Variables (In a Hierarchical Control Environment), Proceedings of the 1985 USENIX Conference
(Accessed November 7, 2025)