6 ms·

perhaps the kernel, but i suspect that much of the userland (which is a lot of what i reference here when i say "unix"- all the command line utilities, shells,

by a-dub 4y ago

perhaps the kernel, but i suspect that much of the userland (which is a lot of what i reference here when i say "unix"- all the command line utilities, shells, the C programming language) was influenced by the needs of both the research community and the technical operation of the telephone network itself.

woodruffw 4y ago
I'm more than happy to be corrected about this, but my understanding is that the groups at Bell Labs that created and matured Unix were not closely tied into the telephony groups, if at all. The lack of interest in telephony use cases is evidenced by early releases and "workbench" distributions for Unix: PWB/Unix[1] focused on providing a development environment for programmers, and WWB[2] was aimed at technical editors and writers. (The functionality of the basic Unix tools reflects this lineage: there a lot of tools for munging text, and very few tools for interacting with peripherals and hardware that isn't a teletype or line printer.) [1]: https://en.wikipedia.org/wiki/PWB/UNIX https://en.wikipedia.org/wiki/PWB/UNIX [2]: https://en.wikipedia.org/wiki/Writer%27s_Workbench https://en.wikipedia.org/wiki/Writer%27s_Workbench
- a-dub 4y ago
  good question. i sent al aho an e-mail. hopefully he'll reply with some interesting history. watch this space!
  - a-dub 4y ago
    Was there anything specific about Bell Labs or working for the Bell system that influenced the design of UNIX and the userland tools? Did the needs of the Bell system influence any of this work, or was it pure computer science research (and the needs of the computer science research community) that influenced these designs? If awk were "designed for someone" who was it designed for? Did anyone who worked on UNIX or the computing stuff at Bell labs care about building things for telephone network operations or was it pure research and technology development for the art of it? -- Good question! Many books have been written about why Bell Labs was so successful in creating research innovations that changed the world. Bell Labs was interested in building operating systems even before the 1950s for use in AT&T's operations support systems for the global telephone network. (You might look at the Wikipedia article on BESYS.) In 1964 Bell Labs joined with MIT and General Electric to create an advanced operating system called the Multics project. (The article Unix and Multics at https://multicians.org/unix.html https://multicians.org/unix.html provides a lot of useful background. Also see Dennis Ritchie's article, The Evolution of the Unix Time-sharing System, which is a must read on the early development of Unix.) In the 1960s Ken Thompson at the Computing Sciences Research Center at Bell Labs, Murray Hill, NJ worked on the Multics project. When Bell Labs pulled out of the Multics project in 1969, Ken Thompson on his own decided to build a much simpler operating system which became known as Unix. Dennis Ritchie, also in the CSRC at Bell Labs, joined Ken in creating Unix. Dennis invented the C programming language for this effort. Subsequently, many people in the CSRC and elsewhere contributed to the development of Unix. Doug McIroy (Ken Thompson's boss and the inventor of coroutines and pipes) deserves a lot of credit for shepherding the development of Unix. The reason Unix and C became so successful is that they were designed by individuals with very good technical taste and not by committees. The Bell Labs research culture also let individuals have great discretion in determining what direction their research should take and one of the important functions of management was to provide adequate resources to make research projects successful and ultimately beneficial to the development of the global telecommunications infrastructure. Another motivating force for Bell Labs research was to create a patent portfolio for the company that could be used to get access to patents of other companies by cross-licensing. What I found immensely gratifying by being involved with Unix was what Don Knuth had once told me. He said, the best theory is motivated by practice and the best practice by theory. As for the motivation behind awk, I recommend looking at https://www2.computerworld.com.au/article/216844/a-z_programming_languages_awk/ https://www2.computerworld.com.au/article/216844/a-z_program...
- jcrawfordor 4y ago
  Yes, for the large part the computing work at Bell Labs was of a separate and distinct lineage from telephony. The story is somewhat complicated by AT&T's corporate history, as prior to divestiture AT&T was, for the most part, prohibited from selling "computers" as part of the terms of their regulated monopoly. In part as a result of this regulatory situation, the computing work at Bell Labs was viewed as more theoretical than applied. Telephone switching equipment itself, such as the ESS, never ran Unix. This is rather complicated by the fact that some sources (not incorrectly) describe the 5ESS as running UNIX, but in fact the so-called UNIX-RTR they ran was an independently developed operating system that featured partial UNIX compatibility. This was largely for convenience as by that time UNIX was often being used as a development and build environment for switching software. It's easy to see why UNIX wasn't really involved in the telephone system itself: UNIX was designed as an operating system for mid and minicomputers such as the PDP that featured a largely "conventional" (from the modern perspective, the matter was less settled at the time) Von Neumann architecture with opportunistic scheduling. Telephone switches, back to the 1ESS and back to the XBAR if you choose to view it as a computing machine, tended to be Harvard architecture with real-time scheduling. This was viewed a far more suitable for telephone equipment since it had extremely high uptime and reliability requirements compared to computers. This comes from the different applications: in the '70s computers were still viewed as machines for offline processing in batch mode, where failures were handled by backing out and restarting the batch. Telephone switches were online machines that could not restart their work from the beginning without disrupting calls in progress. These were basically two completely separate lineages of computing machines that had little in common until the '90s, although the PDP itself was an important step in eroding that divide since it was popular for process control applications (this history relates to the reason the PDP was called the PDP). Keep in mind as well that telephone switching equipment of that era made heavy use of hardware reliability measures (lockstep synchronization of redundant control modules and a large amount of "safety" logic implemented in hardware) as well as running almost entirely from read-only storage (in its most extreme form, the metal punchcards used by the 1ESS). These were further factors that made phone switches dissimilar enough from "computers" that they ran quite distinct software, which usually lacked many of the elements that we would now consider part of an "operating system" (e.g. dynamic process scheduling). To some extent this is still true although e.g. Nortel DMS is more often running off of RHEL-based controllers now. General-purpose mainframes and minicomputers were heavily used within AT&T but for offline applications such as billing, accounting, and maintenance management. For example, many electronic exchange switches were originally paired with a PDP-11 class machine that tracked maintenance and fault data for the office to replace the original paper tickets. Over time these machines gained more capabilities such as automatic line testing, but they remained "external" to the phone switch for reliability reasons. Billing was, for the most part, done by physically removing the tapes from the switch's data recorder and loading it into a computer to totalize and generate bills. Later on this process was automated but still with a clear separation of the switching system and the billing system. Post 1984 AT&T, no longer a regulated monopoly, was permitted to compete directly with IBM, Lexmark, etc with their computing division. The venture was an infamous failure, and AT&T never saw real traction as a computer vendor. AT&T's rapid technical development but failure to actually build a sustainable computer business is what brought us the UNIX ecosystem: they built it, but they couldn't sell it, so eventually they basically gave up and licensed it to anyone with a pulse.

by a-dub 4y ago

woodruffw 4y ago

I'm more than happy to be corrected about this, but my understanding is that the groups at Bell Labs that created and matured Unix were not closely tied into the telephony groups, if at all. The lack of interest in telephony use cases is evidenced by early releases and "workbench" distributions for Unix: PWB/Unix[1] focused on providing a development environment for programmers, and WWB[2] was aimed at technical editors and writers. (The functionality of the basic Unix tools reflects this lineage: there a lot of tools for munging text, and very few tools for interacting with peripherals and hardware that isn't a teletype or line printer.) [1]: https://en.wikipedia.org/wiki/PWB/UNIX https://en.wikipedia.org/wiki/PWB/UNIX [2]: https://en.wikipedia.org/wiki/Writer%27s_Workbench https://en.wikipedia.org/wiki/Writer%27s_Workbench

a-dub 4y ago
good question. i sent al aho an e-mail. hopefully he'll reply with some interesting history. watch this space!
- a-dub 4y ago
  Was there anything specific about Bell Labs or working for the Bell system that influenced the design of UNIX and the userland tools? Did the needs of the Bell system influence any of this work, or was it pure computer science research (and the needs of the computer science research community) that influenced these designs? If awk were "designed for someone" who was it designed for? Did anyone who worked on UNIX or the computing stuff at Bell labs care about building things for telephone network operations or was it pure research and technology development for the art of it? -- Good question! Many books have been written about why Bell Labs was so successful in creating research innovations that changed the world. Bell Labs was interested in building operating systems even before the 1950s for use in AT&T's operations support systems for the global telephone network. (You might look at the Wikipedia article on BESYS.) In 1964 Bell Labs joined with MIT and General Electric to create an advanced operating system called the Multics project. (The article Unix and Multics at https://multicians.org/unix.html https://multicians.org/unix.html provides a lot of useful background. Also see Dennis Ritchie's article, The Evolution of the Unix Time-sharing System, which is a must read on the early development of Unix.) In the 1960s Ken Thompson at the Computing Sciences Research Center at Bell Labs, Murray Hill, NJ worked on the Multics project. When Bell Labs pulled out of the Multics project in 1969, Ken Thompson on his own decided to build a much simpler operating system which became known as Unix. Dennis Ritchie, also in the CSRC at Bell Labs, joined Ken in creating Unix. Dennis invented the C programming language for this effort. Subsequently, many people in the CSRC and elsewhere contributed to the development of Unix. Doug McIroy (Ken Thompson's boss and the inventor of coroutines and pipes) deserves a lot of credit for shepherding the development of Unix. The reason Unix and C became so successful is that they were designed by individuals with very good technical taste and not by committees. The Bell Labs research culture also let individuals have great discretion in determining what direction their research should take and one of the important functions of management was to provide adequate resources to make research projects successful and ultimately beneficial to the development of the global telecommunications infrastructure. Another motivating force for Bell Labs research was to create a patent portfolio for the company that could be used to get access to patents of other companies by cross-licensing. What I found immensely gratifying by being involved with Unix was what Don Knuth had once told me. He said, the best theory is motivated by practice and the best practice by theory. As for the motivation behind awk, I recommend looking at https://www2.computerworld.com.au/article/216844/a-z_programming_languages_awk/ https://www2.computerworld.com.au/article/216844/a-z_program...
jcrawfordor 4y ago
Yes, for the large part the computing work at Bell Labs was of a separate and distinct lineage from telephony. The story is somewhat complicated by AT&T's corporate history, as prior to divestiture AT&T was, for the most part, prohibited from selling "computers" as part of the terms of their regulated monopoly. In part as a result of this regulatory situation, the computing work at Bell Labs was viewed as more theoretical than applied. Telephone switching equipment itself, such as the ESS, never ran Unix. This is rather complicated by the fact that some sources (not incorrectly) describe the 5ESS as running UNIX, but in fact the so-called UNIX-RTR they ran was an independently developed operating system that featured partial UNIX compatibility. This was largely for convenience as by that time UNIX was often being used as a development and build environment for switching software. It's easy to see why UNIX wasn't really involved in the telephone system itself: UNIX was designed as an operating system for mid and minicomputers such as the PDP that featured a largely "conventional" (from the modern perspective, the matter was less settled at the time) Von Neumann architecture with opportunistic scheduling. Telephone switches, back to the 1ESS and back to the XBAR if you choose to view it as a computing machine, tended to be Harvard architecture with real-time scheduling. This was viewed a far more suitable for telephone equipment since it had extremely high uptime and reliability requirements compared to computers. This comes from the different applications: in the '70s computers were still viewed as machines for offline processing in batch mode, where failures were handled by backing out and restarting the batch. Telephone switches were online machines that could not restart their work from the beginning without disrupting calls in progress. These were basically two completely separate lineages of computing machines that had little in common until the '90s, although the PDP itself was an important step in eroding that divide since it was popular for process control applications (this history relates to the reason the PDP was called the PDP). Keep in mind as well that telephone switching equipment of that era made heavy use of hardware reliability measures (lockstep synchronization of redundant control modules and a large amount of "safety" logic implemented in hardware) as well as running almost entirely from read-only storage (in its most extreme form, the metal punchcards used by the 1ESS). These were further factors that made phone switches dissimilar enough from "computers" that they ran quite distinct software, which usually lacked many of the elements that we would now consider part of an "operating system" (e.g. dynamic process scheduling). To some extent this is still true although e.g. Nortel DMS is more often running off of RHEL-based controllers now. General-purpose mainframes and minicomputers were heavily used within AT&T but for offline applications such as billing, accounting, and maintenance management. For example, many electronic exchange switches were originally paired with a PDP-11 class machine that tracked maintenance and fault data for the office to replace the original paper tickets. Over time these machines gained more capabilities such as automatic line testing, but they remained "external" to the phone switch for reliability reasons. Billing was, for the most part, done by physically removing the tapes from the switch's data recorder and loading it into a computer to totalize and generate bills. Later on this process was automated but still with a clear separation of the switching system and the billing system. Post 1984 AT&T, no longer a regulated monopoly, was permitted to compete directly with IBM, Lexmark, etc with their computing division. The venture was an infamous failure, and AT&T never saw real traction as a computer vendor. AT&T's rapid technical development but failure to actually build a sustainable computer business is what brought us the UNIX ecosystem: they built it, but they couldn't sell it, so eventually they basically gave up and licensed it to anyone with a pulse.