Aka “Windows subsystem for Linux”

Once upon a time, straight outta school, I wrote up solutions to problems from the Serway physics book. For Chegg. $5 per problem.

Fuck Chegg.

Yeah. He’s just wearing some kind of standard Bajoran civilian uniform, right?

(And the military Bajoran uniform is red)

DLR trains do, and several airport trains.

Some London Underground lines have drivers that only intervene in the automatic operation of the train in an emergency or abnormal condition.

And they are all welcome back if they can satisfy the Linux Foundation that they’re not affiliated with a sanctioned entity on the SDN list.

Oh they really did. Except because it was the 90s it was real analog closed circuit television, and nothing was wireless.

It was the one piece of NASA training that you just graded yourself on.

This is exactly how NASA built the Space Shuttle Toilet Simulator.

Compare with the yearly release cycle on cars.

Kill -9 is a command on Unix and Linux to send signal 9 (SIGKILL) to a process. That’s the version of kill that is the most reliable and has immediate effect.

Taskkill is a Windows command line program. I believe that taskkill /f uses the TerminateProcess() API. This is more forceful than the End Task button on the Task Manager. There is a different End Process button on the Task Manager that does use TerminateProcess().

TerminateProcess() is pretty reliable, but it doesn’t form part of the C signals stack on Windows like kill -9. So for instance, if you’re doing process control on Python, you need to use a special Windows-only API to access TerminateProcess().

802.11ax, clients just… (essentially) wait for a random amount of time, listen for a break in the signal, and take a leap of faith.

Ethernet originally worked the same way, back when it competed directly against token ring. Ethernet won by being as reliable in real world scenarios while being cheaper to build out. Gigabit Ethernet was the first standard that insisted on full duplex only.

Half duplex mode with the collision avoidance is still actively supported for 10/100, but it is becoming very hard to find an unswitched hub. So you may have to write up your own twisted pair cables.

Those people are almost as bad as the junior devs that are very confidently incorrect.

E. coli is a coliform bacteria. That means it’s found in, you guessed it …shit. So E. coli is a great topic for a shitpost.

How the E coli gets from the shit to the meat is left as an exercise to the reader.

Category: existential horror.

Here’s my guess. I don’t know anything about this particular device, but I have worked with medical devices.

A powered exo-skeleton sounds like it might be a class II medical device. Being a medical device, the OEM was required to produce a safety risk analysis per ISO 14971 in the EU and 21 CFR 820 in the US. I don’t know what all was listed, but probably one of the safety risks was thermal runaway from the (assumed) lithium ion batteries.

Lithium ion battery packs have a well known problem with occasionally overheating and catching fire. This famously delayed the launch of the 787 Dreamliner. This is also why you can’t put your phone or laptop battery into your checked luggage.

In the original risk analysis, there will be a number of mitigation steps identified for each hazard. For the lithium thermal runway, these probably include a mix of temperature monitoring, overheat shutdown, and passive design features in the battery pack itself to try to keep the impacts of over temperature and fire away from the patient.

So how does the price get to 100k? It could be some kind of unique design features that are now out of production and the original tooling is not available. The 100k cost is probably something like to redesign the production tooling, particularly if you have to remake injection molds.

You can’t just use any off the shelf battery pack, because that would invalidate the risk analysis. You’d need to redo the risk analysis, repeat at least some amount of validation testing, and possibly resubmit an application to the FDA.

TLDR: you can get some MEs and EEs together to solve this problem, but once they’re on the case, you can blow through 100k real fast.

the sacred chickens do not approve.

It used to be that 640K oughta be enough for anyone.

Medical devices are required to comply with 21 CFR 820 in the United States, which establishes quality management standards. This includes minimum standards for the software development lifecycle, including software verification and validation testing.

In the EU, broadly equivalent standards include ISO 13485 and IEC 62304.

If an OEM wants to do a software update, they at minimum need to perform and document a change impact analysis, verification testing, and regression testing. Bigger changes can involve a new FDA submission process.

If you go around hacking new software features into your medical device, you are almost certainly not doing all of that stuff. That doesn’t mean that your software changes are low quality–maybe, maybe not. But it would be completely unfair to hold your device to the standard that the FDA holds them to–that medical devices in the United States are safe and effective treatments for diseases.

This may be okay if you want to hack your own CPAP (usually a class II device) and never sell it to someone else. But I think we all need to acknowledge that there are some serious risks here.

The Linux software you can get as a regular user from your typical Linux distributions is absolutely not any more secure on average than your typical Windows software.

I say this as someone who writes application programs on both systems.

I think it’s really debatable whether the Linux kernel is really any more secure than the Windows NT kernel. Linux advocates have pushed the “many eyes, shallow bugs” line for a long time, but high profile lapses seem to really have put the lie to that.

There’s a technique called “heel-toe” shifting which involves using different parts of the right foot to operate the brake and throttle at the same time, while the left foot works the clutch.