#include <windows.h>

void ScreenCap (TCHAR* file) {
	HBITMAP hDIB;
	BITMAPINFOHEADER bmpih;
	BITMAPFILEHEADER bmpfh;
	HDC hdc, hdcOld, hdcMem;
	BYTE* imgBuf;
	HANDLE hFile;
	DWORD written;
	UINT	w = GetSystemMetrics (SM_CXSCREEN),
			h = GetSystemMetrics (SM_CYSCREEN),
			size = w * h * 3;
	
	// Allocate image buffer
	imgBuf = new BYTE[size];

	// Initialize bitmap information header
	bmpih.biSize = sizeof(BITMAPINFOHEADER);
	bmpih.biWidth = w;
	bmpih.biHeight = h;
	bmpih.biPlanes = 1;
	bmpih.biBitCount = 24;
	bmpih.biCompression = BI_RGB;
	bmpih.biSizeImage = sizeof(imgBuf);
	bmpih.biXPelsPerMeter = 0;
	bmpih.biYPelsPerMeter = 0;
	bmpih.biClrUsed = 0;
	bmpih.biClrImportant = 0;

	// Capture Screen
	hdc = GetDC (NULL);
		hDIB = CreateDIBSection (hdc, (BITMAPINFO*)&bmpih, DIB_RGB_COLORS, (void**)&imgBuf, NULL, 0);
		hdcMem = CreateCompatibleDC (hdc);
		hdcOld = (HDC) SelectObject (hdcMem, hDIB);
		BitBlt (hdcMem, 0, 0, w, h, hdc, 0, 0, SRCCOPY);
		SelectObject (hdcMem, hdcOld);
	ReleaseDC (NULL, hdc);

	// Initialize bitmap file header
	bmpfh.bfType = *(WORD*)"BM";
	bmpfh.bfOffBits = sizeof(BITMAPFILEHEADER) + bmpih.biSize;
	bmpfh.bfSize = bmpfh.bfOffBits + bmpih.biSizeImage;
	bmpfh.bfReserved1 = bmpfh.bfReserved2 = 0;
	
	// Write bitmap to file
	hFile = CreateFile (file, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
	if (hFile != INVALID_HANDLE_VALUE) {
		WriteFile (hFile, &bmpfh, sizeof(BITMAPFILEHEADER), &written, NULL);
		WriteFile (hFile, &bmpih, sizeof(BITMAPINFOHEADER), &written, NULL);
		WriteFile (hFile, imgBuf, size, &written, NULL);
		CloseHandle (hFile);
	} else {
		MessageBox (NULL, file, NULL, MB_OK);
	}
}