DOI: 10.1145/361011.361061. The UNIX time-sharing system

10.1145/361011.361061

Crossref journal-article

Association for Computing Machinery (ACM)

Communications of the ACM (320)

Abstract

UNIX is a general-purpose, multi-user, interactive operating system for the Digital Equipment Corporation PDP-11/40 and 11/45 computers. It offers a number of features seldom found even in larger operating systems, including: (1) a hierarchical file system incorporating demountable volumes; (2) compatible file, device, and inter-process I/O; (3) the ability to initiate asynchronous processes; (4) system command language selectable on a per-user basis; and (5) over 100 subsystems including a dozen languages. This paper discusses the nature and implementation of the file system and of the user command interface.

Bibliography

Ritchie, D. M., & Thompson, K. (1974). The UNIX time-sharing system. Communications of the ACM, 17(7), 365â375.

Authors 2

Dennis M. Ritchie (first)
Ken Thompson (additional)

References 9 Referenced 727

Digital Equipment Corporation. PDP-11/40 Processor Handbook 1972 and PDP-I 1/45 Processor Handbook 1971. Digital Equipment Corporation. PDP-11/40 Processor Handbook 1972 and PDP-I 1/45 Processor Handbook 1971.
10.1145/363848.363863
{'key': 'e_1_2_1_3_2', 'first-page': '557', 'volume-title': 'Proc. AFIPS 1969 SJCC', 'volume': '34', 'author': 'Richards M. BCPL'} / Proc. AFIPS 1969 SJCC by Richards M. BCPL
10.1145/800197.806050
Ritchie D.M. C reference manual. Unpublished memorandum Bell Telephone Laboratories 1973. Ritchie D.M. C reference manual. Unpublished memorandum Bell Telephone Laboratories 1973.
{'key': 'e_1_2_1_7_2', 'first-page': '2', 'volume': '1', 'author': 'Aleph', 'year': '1971', 'journal-title': 'Practice and Experience'} / Practice and Experience by Aleph (1971)
Deutsch L.P. and Lampson B.W. SDS 930 time-sharing system preliminary reference manual. Doc. 30.10.10 Project G ENI E U of California at Berkeley Apr. 1965. Deutsch L.P. and Lampson B.W. SDS 930 time-sharing system preliminary reference manual. Doc. 30.10.10 Project G ENI E U of California at Berkeley Apr. 1965.
10.1145/800212.806497
10.1145/361268.361271

Dates

Type	When
Created	23 years, 1 month ago (July 27, 2002, 7:34 a.m.)
Deposited	2 months, 1 week ago (June 17, 2025, 12:45 p.m.)
Indexed	4 days, 22 hours ago (Aug. 23, 2025, 9:50 p.m.)
Issued	51 years, 1 month ago (July 1, 1974)
Published	51 years, 1 month ago (July 1, 1974)
Published Online	51 years, 1 month ago (July 1, 1974)
Published Print	51 years, 1 month ago (July 1, 1974)

Funders 0

None

BibTeX

@article{Ritchie_1974, title={The UNIX time-sharing system}, volume={17}, ISSN={1557-7317}, url={http://dx.doi.org/10.1145/361011.361061}, DOI={10.1145/361011.361061}, number={7}, journal={Communications of the ACM}, publisher={Association for Computing Machinery (ACM)}, author={Ritchie, Dennis M. and Thompson, Ken}, year={1974}, month=jul, pages={365–375} }

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