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Back in 1993, I was taking a number theory class

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Re: Back in 1993, I was taking a number theory class

#81

Post by asdff »

Jtsummers wrote: post #22
908B64B197 wrote: post #13

Earlier quoted context omitted.

> For anyone still at or associated with a university, how would they react to behavior like this today? They would wonder why the student went through all that trouble instead of getting time on our HPC cluster.

Hah, fair enough, HPC clusters are certainly more common than when I went to school. In that case, take the "like" to be a generalization (how I meant it): A student (or students) pushing the limits of the existing rules and infrastructure to accomplish something productive or interesting. Yes, it breaks some rules, but what's a typical reaction anymore? Do they get hired by the university or pushed to work with part…

Today the sysadmin sends you a frustrated email at you asking you not to do that again. You are using someone else's stuff that is carefully maintained by other people, it's polite to abide by the rules these maintainers have set up since it's their job and their free time on the line when things go wrong.

Re: Back in 1993, I was taking a number theory class

#82

Post by thaumaturgy »

tbrock wrote: post #74
thaumaturgy wrote: post #32

Ah yes, good memories. I'm having a really hard time right now remembering the name of that program that blocked access to the Finder; I think it was "Easy"-something. Google fails me on the name too. Breaking it was a hobby. Some school labs had left access to Hypercard available through that program, so you could just pull up Hypercard and make a new stack that would tell the program to quit. The other way to get a…

The name of the program was "At Ease". It had two big folders with icons that looked very much like a precursor to iOS's springboard we know today. The two folders were labeled "Applications" and "Documents": https://en.wikipedia.org/wiki/At_Ease You could also trigger the NMI via Apple key + power button and I remember the magic code to set the memory to zero and crash finder being: SM 0 A964 G O

Close. Usenet for the tiebreaker:

> At the ">" ROM debugger prompt, type the following lines, pressing Return after each:

> SM 0 A9F4

> G 0

> In the first line, the "SM" stands for "Set Memory", the "0" signifies memory location "0", and the "A9F4" is the trap number for the "ExitToShell" trap. This line puts "A9F4" at memory location "0". In the second line, the "G" stands for "Go" and the "0" stands for memory location "0". This line tells the computer to execute the instructions starting at memory location "0". Since "A9F4" is at memory location "0", the "ExitToShell" trap is executed.

https://groups.google.com/g/comp.sys.mac.system/c/lM8yT3I3P0...

Re: Back in 1993, I was taking a number theory class

#83

Post by [deleted] »

Someone wrote: post #59
elengyel wrote: post #19

I'd like to clarify that my code was running only on machines that were otherwise idle. Not many people were in the lab late in the evenings. MPQS processing nodes could be added and removed dynamically, so if somebody needed a computer that was part of my cluster, they could just quit my program and everything would go back to normal. Also, once the number theory professor learned of what I had implemented, he worke…

> I could enter that program in the system monitor, but I needed a way to run it. The simple way: in that mini debugger, the ‘G’ command (for ‘Go’) takes an optional address and jumps to it. “G 40F6D8”, for example, continued execution at address 40F6D8.

[deleted]

Re: Back in 1993, I was taking a number theory class

#84

Post by evanreichard »

valyagolev wrote: post #20

Apart from using hacking to overcome imposed limitations such as these, I am amazed by the number of times I had to use my chops to overcome what was simply a bug. Opening the web inspector is such a normal moment of dealing with other people's websites, I have no clue how people manage without it. I was very... surprised when I managed to productively use "javascript:(some code)" in the URL bar of the browser of my…

About a year ago I was attempting to book a room through the Hilton payment system but my card kept getting declined.

Opening up the web inspector revealed that the JS was stripping any leading 0's for the CVV. I ended up manually crafting a curl request to hit the GraphQL endpoint and was able to successfully book the room.

I did reach out to a Platform Architect on LinkedIn describing the bug, but never heard back about it. Was a total shot in the dark, though, so no surprise there.

Re: Back in 1993, I was taking a number theory class

#85

Post by mxcrossb »

a3n wrote: post #45

In 19 and 82 or 3, I worked at Lockheed Shipyard in Seattle, in a sort of tech writing capacity on a Navy ship building project, based on my recent experience in the Navy. The business closed with completion of the ships. We had to fill out lots of forms that documented what we called "analysis," and we'd often have to change them based on some factor changing. One change could cascade through the whole form. Paper f…

Great story. I wonder if somewhere on a site like the daily wtf you can find the sys admin’s retelling where he relays in horror how a bubble sort almost brought down the system!

Re: Back in 1993, I was taking a number theory class

#87

Post by mxcrossb »

tanbog4 wrote: post #61

When I did a university security course a few years ago that involved a contest to factor primes those of us who wanted to be competitive had to buy AWS processing time...

Time to take a hint from the college board and insist that every student’s code has to run on a TI-84

Re: Back in 1993, I was taking a number theory class

#89

Post by wheybags »

I did a nasty hack a little like this when I was in college. College wired internet had all sorts of filters on it, I can't remember the details exactly. The important thing was it didn't allow the upd ports for counter strike from the wired connection we had in a society room. The computer science department had their own web proxy, which was only accessible from inside their network. Cs students could SSH into special lab machines running linux, which were on the cs network. Crucially, you could connect to them from the general college network, not just another cs network ip. These machines had a series of predictable hostnames, iirc lg12l$hostnumber (lg12 was the labs name). So, the solution was in two parts: first, ssh tunnel to the cs dept proxy, second: connect to openvpn on a vps somewhere using a mode that openvpn has which allows use through a http proxy. This happened on a machine running a dhcp server, which then acted as a nat router for the whole room.

The lab machines I was using were physically accessble to students, who could reboot them, shut then down, whatever. So I wrote a script that would iterate through the hostnames until it found one that it could SSH tunnel through. Mostly it used lg12l0, the first host. One day I got an email from the cs dept sysadmin telling me that lg12l0 was a test host in his office, not a real lab machine, could I please use another one? And no complaints over what I was actually doing with it. I still wonder if he noticed. This setup was running for at least a year, maybe two. Sorry about that mate :D

Re: Back in 1993, I was taking a number theory class

#90

Post by yumraj »

a3n wrote: post #45

In 19 and 82 or 3, I worked at Lockheed Shipyard in Seattle, in a sort of tech writing capacity on a Navy ship building project, based on my recent experience in the Navy. The business closed with completion of the ships. We had to fill out lots of forms that documented what we called "analysis," and we'd often have to change them based on some factor changing. One change could cascade through the whole form. Paper f…

And now you’re a semi truck driver.. how did that happen from soft developer to semi truck driver?
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