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cjensen

6,062 karma · joined September 29, 2011

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cjensen··on United Just Grounded Fleet of Planes Because Its No Smoking Signs Don't Turn Off
If the owner(s) are the only ones working, there are no employees.
cjensen··on Too dangerous for C++
The two criticism at the end are... odd.

First, there is criticism that assigning to a shared_ptr is not synchronized so it would be bad to share a single shared_ptr object between threads. True, but that is no different than literally every other non-atomic object in C++. It's not surprising in any way.

Second, there is criticism that assigning to the object pointed at by the shared_ptr is not synchronized between threads. This is odd because that's not actually different than a single thread where there are two shared_ptrs pointing to the same object. That is, even with single threading you have a problem you must be careful about.

cjensen··on Cable companies, automakers try to derail FTC, FCC quest to kill misleading fees
This is the key point here. There are just too many things that genuinely do need regulation and Congress simply doesn't have the time or expertise to deal with everything. Losing Chevron would leave too many things unregulated, and would make it too easy to slip an industry-friendly regulation into a large regulation bill.
cjensen··on Y Combinator CEO Garry Tan's online rant spurs threats to supes, police reports
The problem is that this argument is a logical fallacy. Threats to civic leaders are wrong. Whether or not they are good leaders does not change the wrongness of the threats.

[1] https://en.wikipedia.org/wiki/Whataboutism

cjensen··on Y Combinator CEO Garry Tan's online rant spurs threats to supes, police reports
In law, there is a concept of a "True Threat" [1][2]. Political hyperbole is not a true threat; sending a threatening letter whose only purpose is intimidation may be. So Tan's foolish statements are plainly protected speech, and it is sensible for the recipients of the letters to contact police.

[1] https://uwm.edu/free-speech-rights-responsibilities/faqs/wha...

[2] https://firstamendment.mtsu.edu/article/true-threats/

cjensen··on Florida House of Representatives approves bill to ban social media for kids < 16
Your comment begs the question of whether or not those age restrictions are a "solved problem." In the US, government age restrictions on movies DO NOT exist for the exact reason the government cannot impose age restrictions on social media: the First Amendment flatly forbids it.
cjensen··on Mexico building rail rival as water shortages drain Panama Canal
After a quick glance at maps, it looks like they will also need to build docks and container facilities in both ports. This isn't a terrible idea, but it's costly and requires a lot more than "building a railway."
cjensen··on Smart binoculars can identify 9k birds
In my view, the problem is these do not solve a real problem in birding.

Binoculars are best when looking with the eyes. Fatigue from holding an object at eye level is a serious issue, so they need to be as light as possible. Swarovski is well known as a first-rate manufacturer of bins.

Cameras with expensive lenses are best for taking photos. With expensive glass and stabilization, they have the "reach" to get enough resolution of the target. Then they can fire off a dozen photos in quick succession and once in a while will capture a genuinely good photo.

Seems to me this product is aimed at people with more money than sense. Too heavy and will take too long to id the bird. There's a reason only gimmicky binoculars come with the ability to take photos.

cjensen··on Cancer Is Striking More Young People, and Doctors Are Alarmed and Baffled
You are pointing the finger at things you think are worrisome.

But for this particular issue, the problem is a recent significant change in cancer rates. That means that the cause is likely a recent significant change. The items you listed don't strike me as having changed significantly in decades.

Off hand, I can think of dozens of environmental factors that have changed: increase in acceptance of mental health leading to more Rx for same; vaping; marijuana use; a different mix of recreational drug use; less socializing leading to less physical activity; less air pollution; less physical activity as children due to attitude changes about their safety on their own in public; and a dozen more I didn't think of.

I wish good luck to the medical professionals who need to untangle this and find the source causes.

cjensen··on Asian Arowana: The most expensive pet fish
Non-Asian arowana are legal and common aquarium fish.
cjensen··on Solar Cell Efficiency Table
Yes and no.

Cost per watt is what you want when purchasing a panel to install, and you have sufficient space for what you are purchasing. A buyer's guide like that should also consider longevity and reliability.

The link is not a buyers guide. This is simply a table of efficiencies achieved by various technologies. There are plenty of non-buyer's guide uses for this table. Off the top of my head, this could be helpful in deciding which types of cells to invested in to see if a company could reduce cost and become best on a cost-per-watt basis.

cjensen··on Unaligned accesses in C/C++: what, why and solutions to do it properly
Portably? You don't. That's a CPU limitation for some architectures.
cjensen··on Children, left behind by suburbia, need better community design
As a parent, I was not concerned with that. But everyone has their own worries.
cjensen··on Children, left behind by suburbia, need better community design
The author attends the High School I attended nearly 40 years ago. I was born, raised, and still live in Fremont.

Fremont has begun doing some of these trendy concepts that are mentioned in the article, but when I grew up none of these ideas had been implemented. I socialized with other kids and rode bike around the neighborhood. As a pre-teen, we socialized in the street and at each other's houses. As a teen I was not really restricted in where to go and there are plenty of neighborhood parks and libraries to hang out at.

None of the article's critiques of suburbia ring true to me with respect to Fremont. If you are seeking nightlife as an adult, you might feel it is a wasteland. But for children growing up I'm not seeing a problem. Part of that is that most of the city can be navigated without ever being on an arterial. Part of that is that most of the city was developed during an era where neighborhood parks could be mandated. Part of that is the city was master planned when it was small and they foresaw today's population.

It is true children spend less time outside than they used to. Part of that is fear; when my kids were young, I didn't trust that strangers wouldn't be a problem if they were outside the house. But right or wrong, that fear is worsened by the proposed changes to how suburbs are laid out, not improved.

cjensen··on Simple streetlight hack could protect astronomy from urban light pollution
Why do you think 150Hz is unacceptable? People used to watch 50Hz TV, and weren't bothered too much. And San Jose used to use 60Hz flickering streetlights (sodium? not sure) to reduce light pollution for Lick Observatory.
cjensen··on Rising pay transparency causing an employer compensation information 'arms race'
Employers already had a form of pay transparency in market research. Typically business pay to receive compensation ranges in return for money and for data.
cjensen··on CVS ditches common cold meds after FDA advisers say they're useless
In California, the rate-limit for purchasing pseudoephedrine is insufficient for allergy sufferers. They end up having to go out of their way to stock up during the off-season.
cjensen··on Implication for C++ [pdf]
Insanity!

Programs must be maintained. This means that a programmer must be able to read a program and understand it. Forcing the programmer to understand implication makes no sense.

We do give up understandability already with templates. Templates can be a source of non-understanding, but also there is no replacement for templates. Implications don't need a new feature since ?: already solves this.

Compare this proposal to another weird C feature:

   char \*a;
   ...
   17[a] = 'b';
where, although the array operator is associative, it simply isn't used that way in code because it offers no useful feature. Therefore it is an insane feature which is harmless. The implication proposal is not harmless.
cjensen··on *(char*)0 = 0; – What does the C++ programmer intend with this code? [video]
That is incorrect :-).

sizeof is an operator in C, and does not need parenthesis any more than pointer operator *. It is true that programmers frequently think of it as a function and use parenthesis.

cjensen··on Google opens Falcon, a reliable low-latency hardware transport, to the ecosystem
OSI is an entire networking stack designed by committee that died from disuse [1]. The only thing we now remember of it are the functional layers within the protocol.

For example, people sometimes refer to TCP as a "Layer 4" protocol even though (a) TCP predates the invention of Layer 4 and (b) TCP is a square peg that does not exactly fit into the round hole that is Layer 4.

[1] https://en.wikipedia.org/wiki/OSI_model

cjensen··on *(char*)0 = 0; – What does the C++ programmer intend with this code? [video]
Regarding your PS, I used Borland's Turbo C++ 1.0, and I think you've forgotten that memory models existed. Honestly, that's a good nightmare to forget.
cjensen··on *(char*)0 = 0; – What does the C++ programmer intend with this code? [video]
Not quite. (char *) 0 is the null pointer. The null pointer is not necessarily a binary all-zero. On some compilers in x86, the null pointer intentionally points to something which will cause a crash when written to.
cjensen··on Automakers invented the crime of jaywalking (2015)
The Library of Congress has a great film taken from the front of a cable car in pre-fire San Francisco [1]. It's absolutely terrifying to see how unsafe the streets were. It wasn't just cars either: horse-drawn carts dart in and out of traffic just as cars did, pedestrians cross at-will in front of all vehicles, and at one points kids mess about jumping on the back of vehicles.

It's obvious major regulation was needed, and not just for pedestrians. Pretend cars didn't exist on that street for a moment and think about the changes needed to make it safe: carts needed lanes and rules for changing lanes, cable cars needed dedicated lanes, intersections needed a system to allow traffic from multiple directions, and pedestrians were being a bit too free with their judgement calls.

[1] https://www.youtube.com/watch?v=uINgSqEU26A

cjensen··on RIAA Reports AI Vocal Cloning Site 'Voicify' to the U.S. Government
Cover bands are bands playing other peoples' music. That's an expected use case in our legal system, and the authors of the music are compensated as mandated by the government.

Misrepresenting who performed an audio track is exactly that, a misrepresentation of goods sold. There are laws for that.

There is nothing in law that explicitly permits what AI sites are doing with performers' music. And the sites are not compensating the imitated performers. That's just plagiarism which is already unlawful.

cjensen··on Microsoft says VBScript will be ripped from Windows in a future release
Having written utility scripts embedded into my installer using VBScript, I am not amused. It used to be that MS was known for going to great lengths to achieve backward compatibility, but now even they are infected with CADT programmers.

My only hope is that some BigCOs scream loud enough about MS breaking all their old stuff.

cjensen··on Sonoma's log gets briefer and more secretive
My last fridge literally had the ability to press some buttons to get error information as an encoded sound. An app is used to decode the audio to obtain something that can be read. Sadly it was a break in a component that cannot be swapped out.

I've fixed appliances, and the best source of information about what is wrong is usually the microcontroller. Sometimes it's just a hex error code, and that's enough. A firehose of text like MacOS currently produces is unusable.

cjensen··on Geographic ‘hot spots’ for cigarette and firearm deaths in the U.S.
Some random observations on this...

1. The suicide difference between the Mountain & Basin West vs the Great Plains surprises me. I would have expected Wyoming and Nebraska would have been more similar.

2. The gradient across Texas is interesting, particularly the lack of both suicide and smoking death in the southwest part of the state compared to the northeast.

3. Rural Nevada counties, except the northernmost two, utter lack the suicide rate that is seen in nearly all of Arizona.

4. It's not helpful to conflate these three causes of death. Seems like it would be better as separate maps

5. It's not helpful to color-code these maps as a binary choice between "has problem" and "does not have." I wonder how much subtlety is hidden by not using a gradient.

6. Unlabeled graphs are a sin. What is the definition of "hot spot?" And why is it hidden from the casual reader?

cjensen··on Microsoft’s Revocation of the Verisign Class 3 Public Primary G5 Root Cert
The problem is program executables are signed with digital certificates. So long as they were signed during the valid certificate period, they are supposed to remain signed forever. Revoking an expired base certificate like this is a huge deal and breaks a lot of software.

Airlock is security software. It's not their stuff that is failing -- they are dealing with reports about the issue and letting the world know what they've found.

cjensen··on The missing C++ smart pointer
Seems to me that the critical problem with this idea is "deep copy."

There is no builtin deep copy facility. Without the facility then a box pointer would be dangerous leading to weird effects when the copy is too shallow.

You could solve deep copy with a template that relies on each class providing a deep copy function if one is needed. But again, this will make bugs if someone forgets to provide the function.

Rather than make an error-prone feature in the standard library, I think it would be better to just explicitly roll this yourself. A sensible constructor copy should already do a deep copy -- or ensure copy-on-write to simulate a deep copy. So copying is as easy a calling make_shared (original) or make_unique (original).

cjensen··on “Once” one-time concurrent initialization with an integer
No. PODs that are initialized with no side-effects can be optimized away into compile-time initialization. E.g. if you have an integer that is static inside a function, it can just be initialized old-school.
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