keyboard.c

// gcc -Os -s -nostartfiles -nostdlib -e __main -Wl,-gc-sections win.c -o win -luser32 -lkernel32
#define UNICODE
#include <windows.h>

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);

void _main(){
	MSG msg          = {0};
	WNDCLASS wc      = {0}; 
	wc.lpfnWndProc   = WndProc;
	wc.lpszClassName = L"\x01";
	RegisterClass(&wc);
	CreateWindow(wc.lpszClassName, NULL, WS_OVERLAPPEDWINDOW | WS_VISIBLE, 0, 0, 640, 480, 0, 0, NULL, NULL);
	while(GetMessage(&msg, NULL, 0, 0 ) > 0)
		DispatchMessage(&msg);
	ExitProcess(0);
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){
	switch(message){
		case WM_KEYDOWN:
		{
			BYTE KeyState[256];
			GetKeyboardState(KeyState);
			
			WORD lpChar = 0;
			if(ToAscii(wParam, lParam, KeyState, &lpChar, 0) > 0){
				DWORD lpNumberOfCharsWritten;
				WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE), &lpChar, 1, &lpNumberOfCharsWritten, NULL);
			}
			break;
		}
		case WM_CLOSE:
			PostQuitMessage(0);
			break;
		default:
			return DefWindowProc(hWnd, message, wParam, lParam);
	}
	return 0;
}