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Software IBM

ACP, One of the Oldest Open Source Apps 102

Esther Schindler writes "The Airline Control Program (ACP), introduced by IBM around 1967, predated the term 'open source' by decades. But you may be surprised by how much of its development resembles the FOSS movement today. The article An Abbreviated History of ACP, One of the Oldest Open Source Applications describes what made it special."
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ACP, One of the Oldest Open Source Apps

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  • Anonymous Coward (Score:3, Insightful)

    by Anonymous Coward on Friday August 21, 2009 @07:58AM (#29145229)

    This was how it was back in the days, and that is why RMS started GNU and FSF, to keep it that way.

    • by JBL2 (994604)
      "How it was" -- when the value of the system was concentrated in the hardware. The whole system was set up to serve the most valuable part, and software was seen as "directions to run the hardware" -- important, one supposed, but not the showy part. With commodity hardware, the value is in the bits and bytes now.
      • Re:Anonymous Coward (Score:5, Interesting)

        by xaxa (988988) on Friday August 21, 2009 @09:01AM (#29145825)

        "How it was" -- when the value of the system was concentrated in the hardware. The whole system was set up to serve the most valuable part, and software was seen as "directions to run the hardware" -- important, one supposed, but not the showy part. With commodity hardware, the value is in the bits and bytes now.

        What about most device drivers? They still seem to be closed.

        (RMS was angered when a printer manufacturer wouldn't supply the source code to the printer driver, IIRC.)

        • by MasterOfMagic (151058) on Friday August 21, 2009 @12:02PM (#29148109) Journal

          RMS was angered when a printer manufacturer wouldn't supply the source code to the printer driver, IIRC.

          And what most people miss about this story is not just that the manufacturer wouldn't provide the driver. It was that they refused to provide the driver so that rms could modify it so that MIT could use the hardware in the way that they pleased after paying for it.

          The device was a shiny new laser printer. rms wanted to add a feature to the driver - notifying someone when (not if) the printer jammed so that print jobs wouldn't get backed up when the printer jammed without having to have someone babysit the printer. The printer maker (I believe it was Xerox, but I could be wrong on this part) didn't want to give up the source because they were afraid that it contained trade secrets because they were the only game in town for laser printing.

          The refusal of source code for drivers goes on today, mainly from wireless manufacturers (with the added point that they feel they might be liable if someone violates an FCC reg because they tweaked the driver) and the video card makers.

        • by pavon (30274)

          With commodity hardware, the value is in the bits and bytes now.

          What about most device drivers? They still seem to be closed.

          Reread his last sentence. Most consumer hardware today is fairly basic with all the important functionality implemented in the firmware if you're lucky, or the driver if you're not. Or as is most common, the firmware is just a "bootloader" that has all it's real code (a binary blob) uploaded by the driver each time it is initialized.

          That was JBL2's whole point - even device drivers have as much or more value than the hardware they were written for these days.

    • As others have pointed out, this was driven by technological limitations of the time along with the fact that software was often bundled with hardware. In that era computers were so expensive customers often leased rather than owned as well.

      Once the price of hardware came down and money could be made from software alone, the source was no longer given away. Had RMS actually worked in the real business world he would have realized that things had already changed outside of academia.

  • 5K bag (Score:1, Funny)

    by Anonymous Coward

    "the ACP programmers I knew spent entirely too much time trying to shove 5K of functionality into a 5K bag. "

    I can do that in my sleep!

  • OS not DOS (Score:3, Informative)

    by Anonymous Coward on Friday August 21, 2009 @08:06AM (#29145301)

    It was not IBM's DOS that inspired _The Mythical Man Month_. It was IBM's OS.

    They cobbled together DOS because OS was so late.

    OS is now z/OS.

    DOS is now z/VSE.

    • Re:OS not DOS (Score:5, Informative)

      by Spiked_Three (626260) on Friday August 21, 2009 @08:57AM (#29145779)
      Agreed - DOS had nothing to do with it.

      But dont forget VM, the first virtualization OS that I know of - and I dont know much about non-ibm computers of that time - but it came out of the necessity of the people who started running DOS while waiting for OS to get finished, and then couldnt afford 2 computers to run simultaneously while they migrated from DOS to OS. and of course, it is now z/VM - and more often used as part of the hardware microcode providing hardware partitioning.

      All early IBM OSs had the source freely available, DOS, OS and VM. I do not think the license restricted redistribution either, since it was available freely from the vendor. The OSs did not become 'licensed' until IBM got tired of supplying the OS for competing hardware - Amdal - and in my mind you can blame the entire software licensing mess of today on a hardware vendor too lazy to write (significant portions of) its own software, and mostly interested in hardware only profits (wow, sounds vaguely familiar even today).

      Anyhow, I was one of those geeky systems programmer guys, making operating system level changes to source code - I never saw it as open source movement though, just something we did to make the OS better fit our needs. 90% of what we needed could be done with vendor supplied 'hooks' that we shimmed in our 'exits' at. I wish more of that kind of thing still existed in all OSs.
  • FOSS? Not sure (Score:3, Informative)

    by filesiteguy (695431) <> on Friday August 21, 2009 @08:16AM (#29145385) Homepage
    Interesting article to be sure -

    However, I'm not sure this really qualifies as OSS or FOSS software. You really couldn't run it on any other system and there was a very closed community of heavy-smoking computer people who were able to run or modify this.

    I did find it cool that the article mentioned -The Mythical Man-Month which I'm reading right now. Funny how different - yet the same - software development is some fourty years later.
    • by mrisaacs (59875)

      Actually there were IBM "clones" after the DOJ forced unbundling of OS and apps from hardware, you could get the code and run it on a number of mainframes that were specifically designed to look like IBMs.

      I'm old enough to have been active in this timeframe (you don't have to get off my lawn).

      Interestingly there was also a budding OSS type effort in the minicomputer world - mostly with a vendor called Datapoint. There were quite a few apps and utilities that had been developed by end-users whose source was

      • Ahh, understand. I wasn't aware that teh other mainframes could run MVS (?) or OS/360 code.

        I'm a newbie to computers as I only started with my TRS-80 in the late '70s. I didn't actually get into mainframes until the late '90s. (I still have nightmares about coding EBCDIC <> ASCII in Visual Basic.)
  • by 10am-bedtime (11106) on Friday August 21, 2009 @08:18AM (#29145399)
    • which stands for Air Traffic Control,
    • which reminds me of playing that game in Emacs the early 1990s (the source was called atc.el, but that doesn't seem to be on the net anymore -- kudos to anyone who can post it here, saving it from otherwise imminent obscurity),
    • which is neither here nor there,
    • but that's what bubbled up from the dregs of memory,
    • which is what happens when you the author encounters YA TLA in TFS,
    • like ATC, LSD, ATP, MCP, MCM, etc etc etc.

    mods: This post is on-topic because its author is old, too! (grumble grumble)

  • Ummm, Spacewar!? (Score:5, Informative)

    by Maury Markowitz (452832) on Friday August 21, 2009 @09:00AM (#29145813) Homepage

    "open source" was the norm for almost all programs in the 1960s. Spacewar was certainly as open as ATP, or more so by most definitions (no commercial claims at all), and was released in 1962. Source code for earlier games, like Nim and Wumpus, were widely available as well.

    This author appears to be committing the sin of omission, conflating his IBM-centric experience with the wider world.


    • Re: (Score:3, Interesting)

      by mrisaacs (59875)

      You're right in that a lot of "public domain" software was distributed as source, but there were no repositories - you could get the original version (or the latest version from the originators) or you could get varients from other developers, but it was rare to have a mechanism in place to submit changes anywhere or pass updates to all the users (remember - no internet, few modems, source mostly passed on 7 or 9 track tape reels).

      When Bulletin Board Systems came into vogue in the late '70s, this started to

      • by Maury Markowitz (452832) on Friday August 21, 2009 @09:27AM (#29146045) Homepage

        > but it was rare to have a mechanism in place to submit changes anywhere or pass updates to
        > all the users (remember - no internet, few modems, source mostly passed on 7 or 9 track tape reels).

        Actually both existed. Spacewar! was distributed primarily in paper-tape form, patches were contributed with paper, scissors and tape.

        No, really.


        • Re: (Score:2, Informative)

          by mrisaacs (59875)

          I did say rare - not unknown.

          The universities and some companies were good about accepting changes and re-issuing,

          I did get a lot of card decks and paper tape while I was in college (early '70s) and at my first couple of employers(same time frame), but a lot of it came 3rd hand or later, and there may not have even been an indication of where it originated from.

          Also a lot of the software came along with a programmer (that is, when someone joined the staff they brought code.) it may not have been theirs orig

        • by nadaou (535365)


          # apt-get install spacewar
          Reading package lists... Done
          Building dependency tree... Done
          E: Couldn't find package spacewar

          how has this not made it into Debian?

        • by thethibs (882667)

          You mean with one of these []?

  • Ever heard of Sabre? (Score:2, Interesting)

    by okvol (549849)
    The IT branch spun off by American Airlines, which outsourced operations to EDS (which was bought by HP). Through a few layers of gateways, Travelocity is in the same room (albeit huge) as the TPF system. They can cluster up to seven of the fastest mainframes to run as a unit with TPF, and have set records for real-time transactions per minute. All this in Tulsa, OK.
  • by toby (759) * on Friday August 21, 2009 @09:39AM (#29146149) Homepage Journal

    IBM had the SHARE organisation [] since 1955. []

    In other words, the open source philosophy has been part of IBM's DNA [] since before most of us were born.

  • by Ancient_Hacker (751168) on Friday August 21, 2009 @10:21AM (#29146639)

    It was only "open source" because the code had to be hand-crafted and re-assembled for each particular configuration. You young kids expect softwar to be rife with XML configuration files, and virtual methods, and hooks. Back in those days the code had to fit into 4K addressable segments, so they could not AFFORD to even think of opening up a file and reading configuration info, or having a table of external procedure hooks. More likely the configuration constants were not even separate, they were convenient opcodes. For instance, if you knew a 707 at this airline always had 112 seats, you'd recall that the HCF opcode happened to be 112 decimal, so you'd compare the seat count against that opcode. All you kids with your fancy separate data! Also it was extreme luxury to have a procedure hook (or as you callem nowadys "virtual methods"). You see you could only call within the current 4K block, and any addresses you wished to pass had similar or worse restrictions. And there was darnlittle dynamc linking available in old IBM DOS, so you could not call anything that had not been linked in last week at the weekly build (which took hours).

    • by Rick.C (626083)
      That's scary that you used the HALT-AND-CATCH-FIRE opcode so often that you still remember its decimal equivalent!
  • No one wants to go on record? IBM got you by the YKWs?

  • 1967? That is old. I am wondering if the original program fell prey to Zawinski's Law []:

    Every program attempts to expand until it can read mail. Those programs which cannot so expand are replaced by ones which can.

    • You do realize that the only kind of mail that existed in 1967 was written on paper and that Zawinski was born in 1968 right?

  • In the mid 80s I did a lot of assembly programming on ACP for KLM. We (125 programmers and me) shared a test system that boasted 128MB RAM and a 100MHz'ish CPU running ACP/TPF. The production system even had double the memory. It could do 100 transactions per second. Touroperators (KLM representatives) all over the world used reservation terminals connected by satellite lines to this mainframe. It definitely was mission critical. But I think the article exaggerates a bit, because internally the story was t

    • At Ramada Inns, it was "go broke in 24 hours." I was quoting. From memory, granted, but the real number they used in the early 80s.
  • Years ago I worked at Western Bancorp. It was the holding company that supported the data processing for 23 banks including First Interstate Bank. We used ACP as the transactional engine running on IBM 370/195 systems. It had better runtime characteristics then the usual IBM stuff. I haven't heard it mentioned for quite a while.
    • When was there a 370/195 at WBDPC?

      I was there from the beginning (when we were still working out of cubicles in IBM's LAX building) and my recollection is that for the first 3 years the biggest CPU that TIPS (Teller Item Processing System) ran on was an 370/147 with 4MB of memory (the 370/147 did about 1.5 MIP on a good day and was slightly faster and cheaper than the 370/145 we traded up from when we moved into the new data center).

      • I worked at the data center on Rosecrans and we had two 370/195's. One was the on-line system, and the other was for development. The programmers used VM/CMS and we used IBM 3600 Finance Industry terminals and teller machines.

10.0 times 0.1 is hardly ever 1.0.