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Port scanning localhost from a webpage has been possible for a long time and does not require websockets.


Maybe I just missed this but can anyone tell me what kernel versions support io_uring. I ran the following test program on 4.19.0 and it is not supported:

    #include <stdio.h>
    #include <stdlib.h>
    #include <sys/utsname.h>
    #include <liburing.h>
    #include <liburing/io_uring.h>

    static const char *op_strs[] = {

    int main() {
      struct utsname u;

      struct io_uring_probe *probe = io_uring_get_probe();
      if (!probe) {
        printf("Kernel %s does not support io_uring.\n", u.release);
        return 0;

      printf("List of kernel %s's supported io_uring operations:\n", u.release);

      for (int i = 0; i < IORING_OP_LAST; i++ ) {
        const char *answer = io_uring_opcode_supported(probe, i) ? "yes" : "no";
        printf("%s: %s\n", op_strs[i], answer);

      return 0;

If you have a clone of the Linux kernel source tree, you just have to look at the history of the include/uapi/linux/io_uring.h file. From a quick look here: everything up to IORING_OP_POLL_REMOVE came with Linux 5.1; IORING_OP_SYNC_FILE_RANGE was added in Linux 5.2; IORING_OP_SENDMSG and IORING_OP_RECVMSG came with Linux 5.3; IORING_OP_TIMEOUT with Linux 5.4; everything up to IORING_OP_CONNECT is in Linux 5.5; everything up to IORING_OP_EPOLL_CTL is in Linux 5.6; and the last three are going to be in Linux 5.7.

This article concurs. https://lwn.net/Articles/810414/ io_uring was first added to the mainline Linux kernel in 5.1.

It is documented in the liburing man pages.

Furthermore, recent variants of io_uring have a probe-function that allows checking for capabilities.

Generally speaking though, you will need more recent kernels than 4.x

io_uring_get_probe() needs v5.6 at least.

Right, but they must retain the original copyright notices and provide the source code. I'm asking the person who bought the software to verify if this is the case.

I don't mind so much someone selling my software on a CD. What I do mind is that they changed the name to trick the buyer. Perhaps I should be using a different license.

GPL allows you to change the name.

I'm not aware of an open source license that prevents someone from renaming the software to whatever they want.

There isn't any open source license that prevents me from not liking it either.

Sorry, but I love caviar. In fact any sort if fish roe is good. It does not have to be expensive. In Russia they eat fish roe/caviar on buttered bread for breakfast. It's really good.

> as there are longer periods of time where they weren't "delicacies" but still tasty parts of a meal.

Yeah that agrees with what I wrote. Why are you apologizing for thinking you are disagreeing

I had the same experience. I called AirBnB and they acted like it was a really strange occurrence and they would look into it. My review never appeared on the host's page. I have zero trust in AirBnB.

You’re right in having no trust in them. Recently I complained about my price increasing by a couple % once I signed up. Nobody could tell me what the problem was. It took them several messages to finally spill up that they were charging me more due to my country’s taxes.

Why is this not clear? Airbnb is so opaque. It would be really easy to list this extra tax but they don’t, so I end up creating a new account.

One person has died in the US. It's not time to panic. I expected more logical comments here.

The concern is people have not been taking this seriously for the past two months. This has resulted in the US being on the back foot and only acting in a reactive manner. The CDC has fallen flat on its face and now state public health departments need to try to pick up the slack. I hope they do.

Other countries are already trying to slow down spread via cancellation of events and closures of schools. The same needs to happen here so that our hospital system has a chance to cope. The real danger is what happens when the 19% of people who get infected that require some level of hospital care can’t get it. The death rates will then rise considerably. Those are preventable deaths if we slow this down.

There needs to be clear and fact based communication from authorities every day about the current situation and what the public can do to play their part. People panic when information is hidden from them, they aren’t stupid they will see what’s going on. They need to know that all the correct things are being done.

> The concern is people have not been taking this seriously for the past two months. This has resulted in the US being on the back foot and only acting in a reactive manner. The CDC has fallen flat on its face and now state public health departments need to try to pick up the slack. I hope they do.

Oh please. There's likely absolutely nothing the CDC could have done to prevent it from entering and spreading within the US, given the nature of the virus. What would have been an ideal situation in your mind, have the CDC order a complete halt to domestic/international travel early January?

Over the last 3 years the CDC funding for participation in international epidemic detection and management programs was cut by 80%. In addition the several most senior positions responsible for pandemic preparation and response were cut. The budget proposed just a few weeks ago again included significant cuts in CDC funding, so the governments eye has not been on the ball for quite some time.

Having said that you’re right that the CDC and health systems in general have mainly and advisory and coordination, rather than a direct role in preventing the spread of a disease. However they need to have the funding, focus and senior representation in order to do that quickly and effectively.

What differences in behaviour would you have expected to see in the CDC if their budget wasn't cut? I'm not seeing it. This thing spreads too fast to meaningfully stop it, China, Korea, Singapore, Japan, are all examples of this

Understanding the disease quickly and slowing down the spread of the disease is incredibly valuable work. Knowing more about it lets us prepare more effectively. If we can reduce the rate at which it spreads, that gives us more the time to prepare for it by training staff and building up stockpiles. Also even if the number of cases ultimately stays the same, if they are spread out over a longer period that means the number of patients needing care at any one time can be dramatically lower, reducing the strain on the health care system and allowing more resources to be devoted to the care of each patient.

The CDC, or some agency in each country anyway, has four roles in this I think.

The first is as part of international monitoring, research and co-ordination efforts. Pandemics are by definition international phenomena and the countries they are most likely to start in are the ones with weak governments or health care infrastructure. This is the first line of defence.

The second line of defence is advice and information, supporting other government institutions and agencies in co-ordinating their resources. Medical expertise is needed to support border control, diplomatic efforts, internal transit networks, government policy, law enforcement, logistics, the list is endless. These all have a role to play in limiting the transmission of the disease and preparing for the eventuality that is reaches populations. They all need expert advice and that advice needs to be prepared in advance and consistent.

Thirdly if the disease does take a grip, co-ordinating local and regional medical resources and efforts. Collecting data from health care networks to track the disease and direct resources where they are needed most, and ensure those resources are used in the most effective and efficient way possible.

Finally, research. This is a long term commitment to developing new equipment, treatments and techniques. This, and all the previous functions operate at the national or even really international level and can't effectively be progressed by fragmented regional or local health care systems. If it's not the CDC it needs to be somebody.

Care to explain what "on the ball" would realistically look like for this specific situation we are in right now? Because everyone else seems to be avoiding the question.

If you're genuinely interested go read how other countries such as Singapore have been handling it. For example Singapore has done a thorough job of testing, tracing, and quarantining individuals and it's slowed the spread dramatically there. They've also been communicating opening and honestly with the public so that the public knows what is happening, knows the right things are being done, and knows what their role is to play.

The CDC used to have a unit in China coordinating with local health care experts to identify and manage epidemics and new diseases. This was cut a few years ago.

Also there used to be a CDC expert on the National Security Council until 2018. Of course you can bring in an advisor as needed, but that’s not the same as having someone you know, and that knows you and how you work, and knows the resources and capabilities you have right there on staff in the NSC.

On the ball would be treating the CDC and pandemic response as national defence, not charity welfare.

"There's likely absolutely nothing the CDC could have done to prevent it from entering and spreading within the US"

The point isn't to prevent it from entering and spreading within the US, but to slow down its spread to give the medical community more time to study it and develop treatments and vaccines, and for the US health care system to prepare by increasing capacity, equipment, training, and staffing.

Sadly, little preparation has been happening because people haven't been taking it seriously, and have been squandering the advanced warnings we've gotten from China.

Something else to consider is that a slowly spreading disease is much easier to manage than a fast-spreading, uncontrolled outbreak. The latter leads to an overwhelmed health care system and many more unnecessary deaths.

In developed countries that have done lots of testing the ratio of infections to deaths is about 50 or 100 to 1. This death implies that there are a lot of undetected infections.

> it's a another red-haired woman

Why is it significant that this post was from a woman or that she has red hair? This comment sounds like a backhanded compliment, at best.

By definition, most people don't need to worry about becoming famous and its consequences.

An LASER cutter is a really productive device to have around. It's very easy to create 2D parts.

Another way to go Open-Source for a lot less money (~$1500) is to buy a K40 on EBay and refit it with a Buildbotics controller.

The other day I needed a faceplate for an outlet with a circular 240v US dryer plug and a two port 120v US plug. I couldn't find anything at the hardware store that would work but I found drawings for the junction box and plugs online. After an hour or two with LibreCAD and CAMotics, I was ready to LASER cut my faceplate from 1/4" poplar. I was really happy when it fit exactly the first time. Now I keep looking behind the dryer to admire my handiwork.

Disclaimer: I'm a creator of CAMotics and Buildbotics.

Slightly offtopic: is poplar really the best material for an electrical wall plate? Wouldn't it be flammable? What's the dielectric withstand going to be like for a wooden wall plate in a humid environment like a laundry room?

solidwood faceplates are not uncommon. take a stroll down the electrical section of a major chain hardware store and you should be able to find a few. a lot of them seem to be made of bamboo. as for the dielectric properties, even in a “humid environment” its unlikely to be an issue. i mean, does a foggy morning short every outlet without a protective cover? if your voltages were high enough, sure you could draw an arc through the humid air...but it seems like you would have to hit closer to the kV range

they make boxes for outlets that are made out of metal ... I don't think that conductivity is a factor

edit here is another example of a wooden faceplate: https://www.amazon.com/Franklin-Brass-W10848-Decorator-Unfin...

Cool products man. Ever done any closed loop with this system?

No closed loop stepper support at this point. We are taking about making a driverless version of the Buildbotics controller which you could pair with any external driver or closed loop steppers.

We play that too. Bluetooth or crazy.

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