I am looking for the standard source code for a keyboard. Is there any where that I can download this source code so that I can modify it for my own use?
No such thing as "standard source code" for a keyboard. Here's a page on the Linux keyboard driver: http://www.linuxjournal.com/article/1080
Your best chance for a Windows keyboard driver will probably be to get the Windows DDK (Device Driver development Kit). OTOH, based on the questions' tags (especially vb.net) I'm left wondering exactly why you'd want that. The keyboard driver itself mostly just gets activated when the user presses a key, gets the data, and goes back to sleep. If you're interested in something like mapping keys to different characters, that's not in the keyboard driver itself at all (without even looking at any code for the driver itself).
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im looking into the WDK at the moment to see how i would be able to make a systemwide keyboard hook on USB keyboards ( and a specific ID ).
What i want to be able to is to filter the keystrokes coming in from that specific USB keyboard (USB HID/keyboard), and be able to send that to a specific application/process only.
Ive seen examples of applications that has to be running that can do that in combination of rawinput and a hook, but i would like it to be systemwide and not demanding an application to run.
I can find examples that makes it quite easy to do with a PS2 keyboard, but when it comes to the USB it starts to look very different.
anyone could suggest me the correct model it has to be based on, and even better examples of how it would be possible to do that ?
and something that would work from XP/windows7 to Windows10 also.
I am interested in writing a program for linux that will read ALL keystrokes, process it and THEN output to the rest of the running processes. Essentially, ALL keyboard input must go into this program and this program alone...Then the program will act as the keyboard for the rest of the computer. I basically want to do something like predictive text on android devices, so my program will act as a filter.
What i'm asking is basically how to direct all keyboard events to my program. While i am not looking for code, i would like to know what part of linux programming/ linux system do i have to learn to be able to complete this task? this, because i am doing this in an attempt to better learn linux.
You shouldn't modify keyboard drivers since this will require you to have a solution for every keyboard manufacturer.(and there are quite a lot of these..)
Instead you should patch a kernel function that is called by all drivers before passing the input further up the stack.
To start with, you could patch input_event which is usually called by all input drivers see documentation here (not only keyboard but also mouse and other devices)
In any case you will have to "decode" the input scan code where you might find this documentation useful.
For more information on kernel patching read here and here.
I am writing an C++ Application and have to read if an arrow key is pressed or not.
I only found some function that are only working on Windows.
You have such problem because you just ask the wrong question. If you application is a command line tool and is accessible from a terminal, than it's just impossible to know which keys are pressed at the moment because the terminal can be far away from the machine where your application runs and which is more important, there is no reason for terminal to send you the arrow key presses because terminal can use them for text navigation.
So you may search how to make the terminal to send you key presses. Not every terminal will support it, but, I think, most of modern terminals in modern OS do.
If you has a gui application that is for running locally and assuming that you control it from the keyboard that is plugged in. Than you should search for the documentation for your gui toolkit. (Qt, wxWidgets, raw xorg, windows API, etc.)
So there are just no native C++ solution for this problem because you question just has no sense in many situations.
So you can use some console library like ncurses or gui toolkit like Qt or search for a native solution in your particular situation, but don't expect this last way will work without any additional code on other machines.
Or just search for other libraries that can allow you to do it.
As you say you only found material for Windows, I assume you are looking for a Linux-Unix way. Old dinosaurs like me remember the time when we only had true consoles (only a keyboard and a 80x25 display). And in these early times existed low-level libraries to interpret keypad transmitted keys and position cursor on screen on almost any terminal, and higher level ones to use the screen as a (text only) GUI.
You should look for curses or ncurses for high level libraries, and terminfo for the low-level capabilities.
I have coded up a low level keyboard hook using SetWindowsHookEX() on Windows CE 4.2 and it seems to work just fine. I am able to see key events using the keyboard and a barcode scanner in notepad and other applications as desired, but I do not see the barcode scanner events in the one application that I want to collect the keys in. I still see events from the keyboard, however, so I know that the keyboard hook is still working and in the hook chain. I have even tried inserting my hook in the chain every millisecond just to see if it would make a difference, but no dice. If I flip back to notepad, it's back to working the way I want it.
I'm not sure what the other application is doing to gain control of the scanner when that application is active that prevents it from acting like a keyboard any more. Any thoughts on this would be greatly appreciated. I've done a bunch of searches without any success. I looked into trying to use RAWINPUT, but it doesn't seem to be supported in Windows CE 4.2 from what I can tell as I don't see the user32.dll in the SDK.
There are two ways to get barcode data on most WEC devices.
The keyboard wedge (where data comes in as as keyboard events)
An OEM specific barcode reader API
If this other app your looking at uses option #2 then there is no keyboard data to retrieve, so it makes sense you wouldn't see any. That said, you might read this article to see if it offers any tips for your keyboard hook.
Functions exported by user32.dll in big Windows are generally found in coredll.dll in WEC/WEH.
-PaulH
How can I completely disable the keyboard using c++ in windows? And by completely disable I mean so even Ctrl+Alt+Delete doesn't work. I did consider using a keyboard driver but I think you need to restart the computer after it is installed, but since I only need to disable it for a couple minutes that wouldn't really work.
This is not really possible.
WinLogon is designed as the one process that intercepts the Ctrl+Alt+Del key press, even when all other things hang or die.
This is the failsafe against malicious sessions, etc. So there is no obvious workaround.
Maybe a keyboard filter driver would make your request possible, but that is a real kernel-driver.
You can't disable Ctrl-Alt-Delete without removing the keyboard or replacing the keyboard driver, it generates a kernel level notification.
You could use BlockInput function. But it doesn't block CTRL + ALT + DEL.
You could install a keyboard hook and filter out the messages, but you might need to have your application as the top most window. Even then Ctrl+Alt+Del would not get filtered out.
Here's SetWindowsHookEx on MSDN
Example of Hooking the Keyboard
Ok, here goes several random suggestions. I don't have a definitite answer, but here's where I would start:
1) SetupDiRemoveDevice is probably the API you want to call. Although to call it, you'll need to make a lot of other device enumeration calls. Enumerate your HID and USB devices and find the keyboard. Start by looking for the VID/PID of the actual device for starters.
2) Delete the drivers kdbclass.sys and kbdhid.sys. You'll be fighting Windows system file to do this. I have no idea if this will work, but sounds interesting and simple.
3) Write a USB filter driver. Your driver will need to know (or be passed) the vid/pid of the device to filter on, but it might work.