We want to create shared data in the virtual memory area in vxWorks. We got some information that we need to use vmLib API for mapping virtual memory to our application. But we dont know much about how to use this. If anybody has used the same or related thing please tell me how to solve the issue.
If you are using VxWorks 6.x, then you can simply use the Shared Data facility present in the OS. Look at the sdLib documentation for the details, but it has a very simple interface.
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I've got a big ask here, but I am hoping someone might be able to help me. If there's another site you think this should be posted on, please let me know.
I'm the developer of the free app Amphetamine for macOS and I'm hoping to add a new feature to the app - keeping a Mac awake while in closed-display (clamshell) mode while not having a keyboard/mouse/power adapter/display connected to the Mac. I get requests to add this feature on an almost daily basis.
I've been working on a solution (and it's mostly ready) which uses a non-App Store helper app that must be download and installed separately. I could still go with that solution, but I want to explore one more option before pushing the separate app solution out to the world.
An Amphetamine user tipped me off that another app, AntiSleep can keep a Mac awake while in closed-display mode, while not meeting Apple's requirements. I've tested this claim, and it's true. After doing a bit of digging into how AntiSleep might be accomplishing this, I've come up with 2 possible theories so far (though there may be more to it):
In addition to the standard power assertion types, it looks like AntiSleep is using (a) private framework(s) to apply non-standard power assertions. The following non-standard power assertion types are active when AntiSleep is keeping a Mac awake: DenySystemSleep, UserIsActive, RequiresDisplayAudio, & InternalPreventDisplaySleep. I haven't been able to find much information on these power assertion types beyond what appears in IOPMLibPrivate.h. I'm not familiar at all with using private frameworks, but I assume I could theoretically add the IOPMLibPrivate header file to a project and then create these power assertion types. I understand that would likely result in an App Store review rejection for Amphetamine, of course. What about non-App Store apps? Would Apple notarize an app using this? Beyond that, could someone help me confirm that the only way to apply these non-standard power assertions is to use a private framework?
I suspect that AntiSleep may also be creating a virtual keyboard and mouse. Certainly, the idea of creating a virtual keyboard and mouse to get around Apple's requirement of having a keyboard and mouse connected to the Mac when using closed-display mode is an intriguing idea. After doing some searching, I found foohid. However, I ran into all kinds of errors trying to add and use the foohid files in a test project. Would someone be willing to take a look at the foohid project and help me understand whether it is theoretically possible to include this functionality in an App Store compatible app? I'm not asking for code help with that (yet). I'd just like some help determining whether it might be possible to do.
Thank you in advance for taking a look.
Would Apple notarize an app using this?
I haven't seen any issues with notarising code that uses private APIs. Currently, Apple only seems to use notarisation for scanning for inclusion of known malware.
Would someone be willing to take a look at the foohid project and help me understand whether it is theoretically possible to include this functionality in an App Store compatible app?
Taking a quick glance at the code of that project, it's clear it implements a kernel extension (kext). Those are not allowed on the App Store.
However, since macOS 10.15 Catalina, there's a new way to write HID drivers, using DriverKit. The idea is that the APIs are very similar to the kernel APIs, although I suspect it'll be a rewrite of the kext as a DriverKit driver, rather than a simple port.
DriverKit drivers are permitted to be included in App Store apps.
I don't know if a DriverKit based HID driver will solve your specific power management issue.
If you go with a DriverKit solution, this will only work on 10.15+.
I suspect that AntiSleep may also be creating a virtual keyboard and mouse.
I haven't looked at AntiSleep, but I do know that in addition to writing an outright HID driver, it's possible to generate HID events using user space APIs such as IOHIDPostEvent(). I don't know if those are allowed on the App Store, but as far as I'm aware, IOKitLib is generally fine.
It's possible you might be able to implement your virtual input device using those.
Can someone please explain how the LUFA library handles USB descriptors? I can't seem to trace the descriptors in any of the examples given back to the source of the library. How do they work? Are they programmed into flash memory at a given location?
Thanks,
George
Descriptors are struct's defined in the LUFA library. You find them in
/drivers/USB/Core/StdDescriptors.h
which is included via the "master include file" /Drivers/USB/USB.h
The user application makes use of these struct's
Please consult the LUFA library documentation and look up "Descriptor" in the search box or expand the File List subtree. This will guide you to info what is defined and where. Also look up the main USB function void USB_USBTask(void).
Another good resource about the basics is this.
I've been told, that a Twisted-based library Ampoule is a great way to create a pool of processes that are executed on different computers. However there is no docs for that and Ampoule's examples also don't make it any clear.
I'd be totally happy with interface similar to stdlib multiprocessing.Pool.map()
Could you supply an example, please?
Ampoule is not natively capable of multi-host operation. Since it uses AMP with strictly defined interactions between the parent and child processes, you could certainly imagine extending it to support multi-host operation. However, you must still solve the problem of connecting to another host (perhaps via SSH using Twisted Conch) and deploying the necessary Python libraries to it for it to be able to execute the tasks you wish to assign to it.
Is it possible to make an operating system using VB.NET?
Yes it is possible to make an operating system using vb.net.
You've got a serious bootstrap problem. Compiled VB.NET code cannot run without the services of the CLR and the JIT compiler. Existing implementations of it (mscorwks.dll and mscorjit.dll for example) have a heavy dependency on services provided by an operating system. You'll have to write your own, that's non-trivial to put it mildly. In addition, many classes in the framework rely on P/Invoke to directly call a Windows API function. Very basic classes like Console, Control, FileStream, Socket. You'll have to replace those too. That's where Singularity was stuck last time I saw a video of it.
The "starter kit" for any project like this is Rotor. That's how Mono got started. Take a look at what your in for, focus on the Platform Adaption Layer (PAL). Needs to be written in unmanaged C/C++ in its current form though.
It has been done (well C# at least, but since they are both CLR languages...)
It's called Singularity by Microsoft Research.
http://en.wikipedia.org/wiki/Singularity_(operating_system)
https://github.com/CosmosOS :::: here is the Answer; Cosmos Allows you to develop your own kernal with c#
Yes, it is possible.
But first you will have to identify what an operating system is; and then define what would you want in your operating system? An operating system does a lot of work on the background as well as on the foreground; there are applications, memory, threading, network, ports, a separate world that make things work.
I would agree with Aviad that probably your OS may be called a .NET CLR, but thats what that would be called. An answer to your question is that it is possible provided that you define your OS and probably limit yourself to what you really require.
No!
Unless you re-define what an operating system is and make the problem fit the solution. This has been standard practice in this industry for decades. Given the right definition of Operating System, you can even use Esperanto to write it:) So what is your definition of Operating System?
Yes, but that would not be easy. Or hard, as a matter of fact. It would be insanely difficult! You would have to write a Visual Basic interpreter (in asm or c), then you would need to implement System and a lot of other CLR stuff. What you may be looking to do is create a virtual OS. This would mean that it lays over the Windows gui and acts as an interface. Good luck.
I'm working on a software project intended for recuperating old specific hardware, mostly for non-for-profit organizations and poor schools.
I need a way to simulate old hardware so I can test the application before shipping it out.
How can I do this?
I'm not sure exactly what the question is asking for. I think you are asking for a way to emulate certain HW?
If that is the case, I've used QEMU in the past, and it has worked great. QEMU is an open source machine emulator and virtualizer.
Use virtual machines? Prepare the images reflecting (more or less) the state of the target machines (speed, hardware, etc). And use them for testing the deployment?
You might want to check out Emulator Zone, and emulator is a good google search term you might not have tried.
Well. If the old hardware is communicating via RS232, then write a class that wraps the RS232 commands and make the class inject the messages the old hardwares would respond. In your program, work against that class instead of real rs232-port and just change instance to real rs232 before shipping.
I have done this succesfully in a project and it worked out really good and its not that complicated that you can think.