This local pdf copy of The UNIX Time-Sharing System article is provided here as a historical reference. The complete details of copyright and reprinting privileges that follow are also contained within the article itself at the bottom of page 1.

Copyright © 1974, Association for Computing Machinery, Inc. General permission to republish, but not for profit, all or part of this material is granted provided that ACM's copyright notice is given and that reference is made to the publication, to its date of issue, and to the fact that reprinting privileges were granted by permission of the Association for Computing Machinery.

This is a revised version of an article appearing in the Communications of the ACM, Volume 17, Number 7 (July 1974) pp. 365-375. That article is a revised version of a paper presented at the Fourth ACM Symposium on Operating Systems Principles, IBM Thomas J. Watson Research Center, Yorktown Heights, New York, October 15-17, 1973.

The following Sixth Edition (V6) UNIX documentation files are provided here under the following Caldera license (local copy) and were obtained from The UNIX Heritage Society (TUHS, see Dennis_v6). The local pdf copy found above was generated from the following files.

The official Communications of the ACM version of this article may also be obtained from