I have two keyboards connected on my computer. I want to use one for the main keyboard, and another for a specific application. For example, keyboard #1 is used for Windows, and keyboard #2 is used only in my application.
Is it possible? If yes, which language should I use? Do I need to access to the driver? I precise that I'm running under Windows...
I found a link that explain step by step how to intercept keyboard keys, and how to identify the device that sent the keystroke.
Using Raw Input from C# to handle multiple keyboards
This example uses C# language.
Related
I am trying to read the input from a barcode scanner that behaves like a keyboard using the hidapi (https://github.com/signal11/hidapi). Apparently the OS does not allow me to access the scanner because it behaves like a keyboard and for security reasons the OS owns all the keyboard and mice devices. The manufacturer of this barcode scanner does not provide any drivers. Is there a way to prevent the OS from owning this barcode scanner or maybe a way to turn it into a serial port and read from it?
In case there is no workaround for this, does anyone know a cheap barcode scanner that does not behave like a keyboard so that I can use the hidapi to access it? Or how can I know that a barcode will not behave like a keyboard? It is a very specific question that most sellers don't know how to reply.
Thanks.
A device that only simulates keyboard input, such as a barcode scanner, does not have a way to control programmatically, rather than an interactive device such as a game controller.
You just wait for the barcode data to be notified as keyboard input data.
It will notify you even if you do not own the device. In other words, you need to own keyboard focus. It is ordinary Windows programming knowledge.
Many keyboard input barcode scanners have the ability to customize prefix / suffix codes that are appended to the front and back to identify barcode data input.
They can be customized by reading the settings barcode.
Check the notified key code one by one in the application program, and if such special data comes, please treat it as barcode data.
By "OS" do you mean Windows? Other operating systems usually provide a means to intercept keystrokes. Linux, for example, has the input subsystem which lets you intercept keyboard events like keys being pressed and released. Unfortunately, these leave it to you to convert to ASCII/UTF-8 characters yourself.
An easier option, regardless of OS, may be to look for a barcode scanner that emulates a USB-Serial device. That would appear to the system as COMx in Windows, /dev/ttyUSBx in Linux, etc. Then you can just read the data from it using a serial port library and not worry about keyboard focus.
I haven't find anything relevant in Google or any Microsoft site about it so I decided to ask a question here.
Everybody knows that in Win-based OS there is a virtual keyboard. I also know that *nix based OS, have it too. So, the question is about:
HOW DOES IT WORK INSIDE?
I mean, let's have an example that I opened on screen keyboard in Windows 10. What's the actual difference between:
input via hardware keyboard: when I'm using it, like I press X button
..and using a virtual keyboard, when I press the same button
Imagine, I have an admin access to terminal/computer, is there any option to track/distinguish that in the second time I pressed button not on hardware keyboard, but on-screen (by mouse clicking) version of it?
And there are also many different software, like AutoIt (yes, it's a language, but it's relevant to this example) that emulating pressing the X button. How does they work in Win-based OS? Do they "in-common" with default on-screen keyboard and using the same driver/WinAPI or there is a difference between them?
And the second case, between:
default on-screen keyboard
compilated AutoIt script
..any other software that emulating press X button
I guess the only way to find out "how exactly button was pressed" is to check current processes list via taskmgr and find out have anything been launched or not. Or I'm totally wrong here, and missing something?
THE SCOPE
I have written a node.js script which emulates button pressing behaviour in windows app.
TL:DR business logic short => open notepad.exe and type `Hello world`
And could someone give me any advice/recommend any powershell/bat script (or any other solution) with demonstration of GetAsyncKeyState check behavior? With which I could easily check my own node.js script (not by functional of it, but by triggering press the X button event)
I found an answer for node.js case here: Detecting Key Presses Across Applications in Powershell
SendInput is the preferred method to generate user input in software. The Windows on-screen keyboard probably uses it for everything except Ctrl+Alt+Delete which I believe has some kind of special handling. The on-screen keyboard is only able to generate Ctrl+Alt+Delete in certain configurations.
Software-generated input is merged with normal hardware input in the RIT (Raw Input Thread) in the kernel.
A low-level keyboard hook can detect software-generated input.
I just bought a new keyboard, and I'm interested in tracking exactly how many keypresses/strokes I make during the entire life of the keyboard. (I would want to just record keyUp, as I don't care about repeats)
I've been googling around for the best way to do this, but I don't even know what approach to take, so I'm having trouble searching intelligently.
Also, the only language I've really worked with is C#. Haven't done anything with C/C++ or WinAPI
Is it difficult to modify the Win 7 drivers directly?
I do want to be able to record keystrokes from the moment the computer boots, but this may not be easily done.
I would prefer to use an existing driver or hook, as I really don't care to get into learning device drivers right now.
I've looked briefly at Ctrl2Cap, but I don't know how to modify something like that to suit my case.
Other questions I looked at,
Writing a keyboard device driver
Low level keyboard Hook not at UI thread
This one indicates writing a USB Filter driver may work, but I have no clue where to start on that.
Disabling the keyboard in windows c++?
It is not necessary to go the driver route, which is not for the faint of heart. You can use use a low level keyboard hook which will work fine from .NET.
I did a quick bing and found the following on codeplex
http://globalmousekeyhook.codeplex.com/
It should get you going
If you want to do that you need to use Kernel Level Keylogger. It's grabs the keystrokes before the operating system takes effects and this one 99% invisible for detection techniques. Then you can grab the Windows Log On screen typed things like password/username etc.
#ChrisTaylor's key logger not work for WinLog-on Screen I reckon. If you can install the keyboard driver filter before the system keyboard device driver take a action you can handle windows user login screen also. But In order to install this driver level key hook you need to have administrator privileges.
I found Unix and Windows Keyloggers from Github. Free to play with this https://www.adlice.com/kernelmode-rootkits-part-3-kernel-filters/ and have fun!
That, what you want is dangerous!
With the same code everyone can create keylogger*
But if you not a virus creator then I recommend you to search "hotkeying in C/C++" or something like that and hook keyboard with hotkeys!
I have written HotKey Maker in VB6 which can make hotkey from every button of keyboard.
But I really not interested in viruses :)
Good Luck !
*Virus which hooks your keyboard and send all what you wrote in keyboard to Virus owner
Is there a way to programmatically find out what kind of keyboard a computer has (i.e. where keys are located, and what extra keys are present in which locations)?
A little error is acceptable, if the keyboard is very non-standard, but in general, the point is to construct an on-screen keyboard-like application that can dynamically draw the keyboard layout on the screen, with high accuracy.
when connected to a computer, keyboards sends "scan codes" to the operating system. on windows, scan codes are then converted into virtual keys (a hardware independent mapping of the keyboard) then to real characters.
the MapVirtualKeyEx() function of the windows API allows you to translate between scan codes, virtual keys and characters. it should also be able to tell you if a key is non-existing.
together with GetKeyboardLayout() which tells you which keybaord is active at any point in time (keyboard layout can be different for different running applications), it should allow you to build a pretty accurate map of the keyboard.
anyway, have a look at the keyboard input section of the MSDN
i will add that all keyboards have almost the same layout. although there is no way to know where a key is physically located, you can probably guess from the scan code and basic knowledge of your own keyboards.
There is no mechanism by which a keyboard can tell Windows what its physical layout looks like. Easy to see with the Windows version of an on-screen keyboard, osk.exe. It seems to be able to guess the form-factor of the machine (laptop vs desktop) but on my laptop it doesn't match the layout of the keyboard.
Use the osk.exe layout as a template so nobody can complain that yours doesn't match well.
I'd like to be able to send key presses from one computer to the other. I have a voice application on one system which I use for my headset, and the other system is my main system. The voice application uses a Push-to-talk (PTT) system, which I'd rather keep.
So what I'd like to do is press a key on my main system and have it sent across the network to my secondary system. At this stage all I know is how to get the key across the network, the specifics of actually detecting the key press on my main system and emulating the press on the secondary system is my problem.
The key I'd like to capture (when held down) and send to my secondary system is the right control key. I think the best way is to add a keyboard hook.
How can I do this in such a way that I can hit right control in any application on my main system and have this application pick that up and send it? When my secondary system receives the key, how do I send it to the entire system (rather than trying to find a specific application)? I'm fine with using low-level Win32 calls in unmanaged C++, I'd just like to know how to get this to work.
Thanks in advance.
It seems like you're already halfway there to your own custom solution, but as an alternate you might want to check out Synergy an open source keyboard and mouse extender.
I found the answer: I wrote a small keyboard hook to pick up the PTT press, and then send it via the network to the secondary system. The secondary system takes this keypress and uses the SendInput function to inject the key into the system input queue. I just tested it with Teamspeak and it works brilliantly.