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SDS940 connection

The first/main TENEX paper ("TENEX, A Paged Time Sharing System for the PDP-10", by Bobrow, Burchfield, Murphy and Tomlinson) specifically calls out the 940 as one of the systems they used as a model. Jnc (talk) 17:17, 29 March 2018 (CEST)

Also, according to "TENEX and TOPS-20", by Dan Murphy (IEEE Annals 37-1, pp. 75-82), BBN actually for a number of years had a 940 with the Berkeley OS on it; so they would have had personal experience with it. Jnc (talk) 17:28, 29 March 2018 (CEST)

Thanks. I did check the Murphy papers, but it doesn't explicitly say that parts could be a close translation, which is what I find interesting. Hopefully, the 940 sources will be available soonish. Larsbrinkhoff (talk) 18:23, 29 March 2018 (CEST)

Hierarchical file system?

I'm not sure, but I have the impression there was no directory hierarchy. Murphy's paper says "We are currently considering the feasibility of implementing a full tree directory structure similar to MULTICS". Budne's TOPS-20 Evolution says it was added in TOPS-20 V3; I have verified this running V3A. Larsbrinkhoff (talk) 10:09, 21 April 2022 (CEST)

Oh, could be. I assumed there were because of my use of TOPS-20 (on MIT-XX) which had them, and since TOPS-20 was based on TENEX... Let me check it out in the TENEX docs (Dan Murphy's site has the ACM paper - I think I have a photocopy somewhere I made 4 decades ago! :-), and then I'll fix the page. Jnc (talk) 18:51, 21 April 2022 (CEST)
Yeah, I think you're right. TENEX, A Paged Time Sharing System for the PDP-10 "1.0 INTRODUCTION" says "File system .. built on multi-level symbolic directory structure", but then "5.0 THE TENEX FILE SYSTEM" says "A symbolic name for TENEX files consists of up to five fields [below - JNC] and thus conceptually represents a tree of maximum depth five. .. This scheme was chosen rather than a full tree to simplify the problem of compatibility with existing DEC PDP-10 software .. We are currently considering the feasibility of implementing a full tree directory structure similar to MULTICS", so it sounds like not. (The 5 fields are "device name, directory name, file name, extension, and version number".) Jnc (talk) 22:02, 21 April 2022 (CEST)
Thanks! I hope to verify this empirically soon. We have the SUMEX-AIM monitor, based on TENEX 1.31, running on a PDP-10 emulator, and are working on bringing up the rest of the system. Larsbrinkhoff (talk) 07:04, 22 April 2022 (CEST)