Many years ago I was a technician supporting a few custom programs on thousands of PCs. The developer of one of these programs had added a date check to his code so the program would refuse to run after a set date and each new release would increase this date by a few months so it would stop working after a few weeks if he ever stopped creating new releases. His contract ended and a few weeks later his software, now relied upon by hundreds of sites, stopped working. The contract for the software development was thoroughly checked and legal action against the developer was started but I asked to see if I could resolve the problem in the meantime.
It only took ten minutes with a dissassembler to find the JGT (Jump if greater than) and convert it to a JLT so the software would stop running if the date was before a certain date rather than after. I created a patching tool that simply flipped one bit that was sent out to all the sites and everything was good again. I don't think I'll ever beat the elegance of a single bit flip hack.
If you think it's bad now, the early days of the web were absolutely filled with scumbag grifters who made small fortunes hiring contractors and then refusing to pay.
Many of them disappeared in the y2k dot com bust, but then seem to have reappeared in SF after 2008.
In the late 1990's, my second ever Flash app development client stiffed me on a $10k invoice.
He finally figured out 6 months later that he didn't have the source material to make changes and paid the full invoice in order to get it.
So I took precautions with the next client. It was a small agency that was serving a much larger business.
We were on 30 days net payment terms and I submitted the invoice when the project was done.
They didn't pay and within a couple weeks of gentle reminders, they stopped responding.
I smiled.
Exactly 30 days from the due date, I got a panicked call shrieking about their largest client website being down and did I have anything to do with it?!
I asked them what the hell they were talking about, they don't own a website. They never paid for any websites. I happen to own a website and I would be happy to give them access to it if they want to submit a payment.
They started to threaten legal nonsense, and how they had a "no time bombs clause in the contract."
I laughed because my contract had no such clause. If they signed such a contract with the client, that's not my problem.
I told them I wouldn't release the source files until the check cleared my bank, which could be weeks. A cashier's check arrived that morning and their source files were delivered.
By the end of it, the folks at the agency thanked me because that client wasn't planning to pay them and they hired me for other work (which, they had to prepay for).
Of course I don't know about the OP, but I'd bet the company was trying to stiff that contractor on their last check.
Mostly non-malicious example... My employer asked me to write a UI to solve a problem for a handful of people until a proper (giant ever-delayed) migration was finished. Over a couple of weeks I made it work despite not having dealt with MVVM/XAML/Whatever before and I was pretty pleased with the outcome. But it was a hacked together thing! I'm not a real dev and given that I got a promise it wouldn't get distributed.
So, you know, in the program.cs startup I checked the username vs a hardcoded list of people in the relevant teams, and if it wasn't crashed out with an error and a support email address.
About 18 months after I had moved on, I got an email with a screenshot of that error message. it would appear the Milan (something like that) office had got their hands on a copy but it just wouldn't work for them...
Trivial to undo of course, but I did enjoy the throwback!
After undergoing stomach surgery 8 years ago I started experiencing completely debilitating stomach aches. I had many appointments with my GP and a specialist leading to endoscopies, colonoscopies, CAT scans, and MRI scans all to no avail and they just kept prescribing more and more anti-acids and stronger painkillers.
It was after seven years of this that I paid for a private food allergy test to find that I am allergic to Soya protein. Once I stopped eating anything with Soya in it the symptoms almost completely vanished.
At my next GP appointment I asked why no-one had suggested it could be an allergic reaction only to be told that it is not one of the things they check for or even suggest. My faith in the medical community took a bit of a knock that day.
On a related note, I never knew just how many foods contain Soya flour that you wouldn't expect until I started checking.
A few months ago I browsed r/all by new and downvoted every crypto scam post to unrelated subreddits I saw. This raised a red flag somewhere inside Reddit (my guess is that I was interfering with some Reddit admin's crypto scams) and my 18 year old account was suspended until I could respond to an email at the address it was registered from that I no longer had access to almost two decades later. An appeal was ignored.
I was furious about losing the account for about two minutes before I realised that nothing of any importance had been lost, shrugged, and created a new account.
It's been a while so I can't provide a link but I remember reading about someone who got hold of a video blackjack machine that used a pseudo random number generator and was able to find the seed from only a few hands and then knew exactly which cards would be dealt next. He then went on to empty every machine he could find in the local casinos.
I think the most probable reason for this instruction is for calculating parity bits. This would need to be done fast so it makes sense that there would be a CPU instruction to do most of the work.
Parity is much easier than counting. It's so easy that you get it for free in the x86 flags register. (… and because the 8008 was designed to run a terminal.)
Each iteration from the 8080 through x64 have a parity bit in the flags register for backwards compatibility with the previous generation. The 8008 was a microprocessor implementation of the Datapoint 2200 architecture.
Early protocols didn’t have error correction in the lower layers. The parity flag was equivalent to a CRC instruction nowadays. Presumably if parity was incorrect, that would mean the byte was transmitted incorrectly.
I ended up being the sole developer for a system that managed vehicle trackers installed in fleet vehicles.
A few months after I took over they picked up a new client that was a finance company for people with bad credit ratings who wanted to purchase vehicles at exhorbitant interest rates. The trackers allowed them to remotely disable vehicles if the finance payments weren't met.
After a while they became the systems's largest customer and finally the only customer. They then asked for some changes so that all their vehicles would be remotely disabled at the start of each month and would be re-enabled when that month's payment was received.
Fortunately, they then purchased the system outright from its current owners and that allowed us to stop developing for them.
"All of them should be allowed on the pavement, because people aren't stupid, they will get out of the way if they see one coming."
Speaking as someone who sometimes puts his back out and spends a few days hobbling slowly about, I shouldn't have to quickly get out of someone's way if I see them coming and they shouldn't be allowed on pavements.
You shouldn't ever have to move out of someones way if they are not walking. I live in NYC so perhaps my perception is skewed but pedestrians should always have the right of way.
Don't move for runners, bikes (shouldn't on sidewalks unless it's a kid) or these things. It's up to the user to manage themselves and prevent themselves from hitting and potentially hurting others.
I see these around here and there, more and more, and don't mind them for now but if we start to get a problem with users hitting people then I'll support a sidewalk ban on them.
The people who hit pedestrians are assholes. Pedestrians have the ultimate right of way. If they refuse to move, then you have to go slow. Just increase fines for hitting people and the problem will go away. Responsible people shouldn't be impacted by assholes who have to shave that last second from their hipster commute.
I wish this were the law everywhere. It varies by jurisdiction. "Each city in California has its own rules about riding a bicycle on the sidewalk. Some cities allow sidewalk riding, some don’t. Check with your city’s municipal code." (http://la-bike.org/resources/california-bicycle-laws)
Assuming you mean where it is an offence to ride on the sidewalk, I'll always choose angry peds or a penalty over getting killed by a coffee-drinking, cell-phone talking urbanite in their range rover. Or non observant lorry driver. Or bus running a red light. Etc.
Cycle a bit in a city and you'll change your view.
Cycling on sidewalks feels safer, but it's actually more dangerous. [1] The problem is that cars don't expect something moving quickly on the sidewalk, and so hit cyclists at driveways and intersections.
There are places that are shared pedestrian/bike paths. The east side of the GG Bridge when the west side is closed for instance. In those cases I think pedestrians should at least be aware of cyclists, instead of walking 4 abreast and blocking the entire way.
I don't own a car and ride almost everywhere. In all the cities I've lived, my experience has been the exact opposite. Since the majority of accidents involve intersections, riding on the sidewalk doesn't do much other than put you in a less visible position, where drivers don't expect you to be and won't be looking for you.
Don't give me that crap. I can't count the number of times I've been nearly run over by cars who refuse to give me my right of way and try every possible trajectory just so they won't be in any way impacted by a person on a bicycle. The only good part about riding on the road is the satisfaction from hearing the honks of asshole cars. I'm taking my right of way and we're paying with our lives if we have to. Fuck cars.
And before you start saying I'll be endangering pedestrians with the same outlook - no. Pedestrians have the ultimate right of way. If there are 8 walking abreast and don't make way when I ring, then so be it, I'll go at 2kph until it's safe to pass them. I'm not in a hurry.
I doubt having your back out is ideal condition for riding a device where you may have to hop a couple of steps to catch your step if you mess up anything.
A bit off topic, but have you tried yoga to help your back problem? I've thrown my back out a couple of times and am in the process of integrating yoga into my daily routine, want to know how well it works (if it works).
Not OP, but while I've had a lot of success, the evidence doesn't support blanket application of 'Yoga' to back pain. The real problem is that back pain typically goes away regardless of treatment modality, which leads to a lot of people who grab the last thing they tried as "the real thing that fixed my back".
yeah, I realize it's not going to cure back pain, I just want it to improve my musculature. I think I keep pulling things because I'm at a computer all day and don't do a lot of movements/stretches.
It's not practical to design everything in the world with the very slowest people in mind. The efficiency losses would be huge. Imagine if every pedestrian crossing light went for five minutes. Vehicular traffic would grind to a standstill.
That said, I see no reason why the people riding these things couldn't just move around other people. I rarely have problems with people on bicycles, because we can mutually avoid each other.
It's not practical to design everything in the world with the very slowest people in mind. The efficiency losses would be huge. Imagine if every pedestrian crossing light went for five minutes. Vehicular traffic would grind to a standstill.
Actually, there was a study in the UK a couple of years ago that didn't get acted on, but which demonstrated that pedestrian crossing lights in British streets allowed so little time for crossing that able-bodied teenagers had to hurry -- middle-aged, elderly, unfit, or handicapped people really need about triple the time.
The solution is probably a combination of the sensor-controlled systems showing up in newer crossings in the UK (IR sensors block traffic by setting a red light until the crossing is clear) and cutting down on automobile use in densely populated areas like urban cores. Ahem. (Hint: why should your one ton rolling steel status symbol trump anybody else's right to use the highway?)
The study was very flawed. The 85 percentile walking speed for pedestrians (1.2 m/s) is for when people start the crossing at the end of green man. So some 15 percent of the people are slower. However if youo take into account most people start crossing before the end of the green man, then the time is ample. "the sensor-controlled systems" - are hopelessly inefficient and actually confusing for pedestrians.
A countdown which displays the time until the red-man is best for a balance of all users.
The green man is intended as a sign that it's safe to _begin_ crossing the road - at least in the UK. You'll notice that the man changes away from Green long before the light sequence. That's intended.
How are you supposed to know how long it has been since the green man appeared? Presumably if it turned green while you were waiting, you would have started walking immediately. Do you have to wait until the next green man if you arrived at the intersection while the light was green?
"The very slowest people" are actually the majority: the elderly, the very young, the temporarily or permanently disabled- if you put all of those people together they're many more than the young, strong and fast.
What's more important, each and everyone of us, will inevitably, at some point in their lives be very young, elderly or disabled. In fact most of us will probably be each of those things during our lifetime.
So it's not so much a matter of efficiency as accepting the fact that human beings are not born with wheels, but with feet and that they should always get priority, despite any misunderstandings about what the purpose of "efficiency" is in the first place.
>"The very slowest people" are actually the majority: the elderly, the very young, the temporarily or permanently disabled
That is quite simply not true. http://www.censusscope.org/us/chart_age.html As you can clearly see, most of the population falls in the age range that has no trouble walking at a reasonable speed. I don't have exact figures on how much of the population is disabled or seriously injured at any given time, but experience says it's not enough to make up for the fact that the very young and the very old are very very far from constituting a majority.
I'll qualify my comment: "the very slowest people" are the majority _in the developed world_ where the median age is 35+ (Wikipedia). It's also where people are the most likely to use hoverboards.
In any case, you can dispute the numbers and it makes no difference. People are not born with wheels. We need space to walk about. By convention and by law, the pavement is not for vehicles.
Despite that, I'm prepared to share the pavement with people on wheels but it has to be absolutely clear that it's not my responsibility to avoid them. It's theirs. They are the ones choosing to put me at risk, they should take full responsibility for it. And watch where the bloody heck they go.
How fast do these go compared to a bicycle? I saw a few of them on the street and they didn't seem to be moving faster than a brisk walker.
My impression was that bikes are generally banned because they move fast enough to cause serious injury yet are silent enough that pedestrians don't hear them coming.
I've seen a few of these in London they aren't really faster than a fast walking speed which makes people who use them look very silly.
They are quite often laughably used in shopping centers or and super markets mostly because allot of the pavements in London are horribly uneven which probably doesn't provide a very good surface for those.
I've seen 2 guys on those things at Westfield last weekend arguing with a bunch of confused staff that didn't knew how to treat them.
I don't really get this device it doesn't help you to commute any faster, it doesn't increase your pedestrian commute range if you aren't fit to walk you won't be able to use one of those (they got quite a stringy weight limit, and require quite a bit of effort to balance yourself on) anyhow.
It's a bit funny to see fit and young hipsters pretty much using a 500$ mobility scooter...
It only took ten minutes with a dissassembler to find the JGT (Jump if greater than) and convert it to a JLT so the software would stop running if the date was before a certain date rather than after. I created a patching tool that simply flipped one bit that was sent out to all the sites and everything was good again. I don't think I'll ever beat the elegance of a single bit flip hack.
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