Windows shutdown functions

Question

Hello,

I am not clear on the windows shut down function. I want the system to shutdown by closing all the apps (controlled shutdown).
The function which is used in the code is

ExitWindowsEx(EWX_FORCE | EWX_SHUTDOWN, 0); 

This does the shut down job but I am not sure if it is correct way to use the function. Could some one help me with this.?

Thank you!

Answer 1

The Document Example implements how the system shut down and all the applications are forced to close.
You can check your code according that.

Answer 2

If you want to Shutdown with a custom warning message, you can do something like this = >

(I commented ExitWindowsEx to test with a Beep)

#define _CRT_NON_CONFORMING_SWPRINTFS  
#define _CRT_SECURE_NO_WARNINGS  
#include <windows.h>  
#include <tchar.h>  
  
#pragma comment(linker,"\"/manifestdependency:type='win32' \  
name='Microsoft.Windows.Common-Controls' version='6.0.0.0' \  
processorArchitecture='*' publicKeyToken='6595b64144ccf1df' language='*'\"")  
  
HINSTANCE hInst;  
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);  
int nWidth = 600, nHeight = 200;  
#define IDC_BUTTON 10  
  
float nTimeEllapsed = 0;  
float nTotalTime = 5000;  
bool bShutDown = false;  
  
int APIENTRY wWinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPWSTR lpCmdLine, _In_ int nCmdShow)  
{  
	hInst = hInstance;  
	WNDCLASSEX wcex =  
	{  
		sizeof(WNDCLASSEX), CS_HREDRAW | CS_VREDRAW, WndProc, 0, 0, hInst, LoadIcon(NULL, IDI_APPLICATION),  
		LoadCursor(NULL, IDC_ARROW), (HBRUSH)(COLOR_WINDOW + 1), NULL, TEXT("WindowClass"), NULL,  
	};  
	if (!RegisterClassEx(&wcex))  
		return MessageBox(NULL, TEXT("Cannot register class !"), TEXT("Error"), MB_ICONERROR | MB_OK);  
	int nX = (GetSystemMetrics(SM_CXSCREEN) - nWidth) / 2, nY = (GetSystemMetrics(SM_CYSCREEN) - nHeight) / 2;  
	HWND hWnd = CreateWindowEx(0, wcex.lpszClassName, TEXT("Test"), WS_OVERLAPPEDWINDOW, nX, nY, nWidth, nHeight, NULL, NULL, hInst, NULL);  
	if (!hWnd)  
		return MessageBox(NULL, TEXT("Cannot create window !"), TEXT("Error"), MB_ICONERROR | MB_OK);  
	ShowWindow(hWnd, SW_SHOWNORMAL);  
	UpdateWindow(hWnd);  
	MSG msg;  
	while (GetMessage(&msg, NULL, 0, 0))  
	{  
		TranslateMessage(&msg);  
		DispatchMessage(&msg);  
	}  
	return (int)msg.wParam;  
}  
  
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)  
{  
	static HWND hWndButton = NULL, hWndStatic = NULL;  
	int wmId, wmEvent;  
	switch (message)  
	{  
	case WM_CREATE:  
	{  
		hWndButton = CreateWindowEx(0, L"Button", L"Click", WS_CHILD | WS_VISIBLE | BS_PUSHLIKE, 250, 10, 60, 32, hWnd, (HMENU)IDC_BUTTON, hInst, NULL);  
		return 0;  
	}  
	break;  
	case WM_COMMAND:  
	{  
		wmId = LOWORD(wParam);  
		wmEvent = HIWORD(wParam);  
		switch (wmId)  
		{  
		case IDC_BUTTON:  
		{  
			if (wmEvent == BN_CLICKED)  
			{  
				nTimeEllapsed = 0;  
				bShutDown = true;  
				BOOL bRet = TRUE;  
				HANDLE hToken;  
				TOKEN_PRIVILEGES tkp;  
				if (bRet = OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken))  
				{  
					LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME, &tkp.Privileges[0].Luid);  
					tkp.PrivilegeCount = 1;  
					tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;  
					bRet = AdjustTokenPrivileges(hToken, FALSE, &tkp, 0, (PTOKEN_PRIVILEGES)NULL, 0);  
				}  
				if (bRet)  
				{					  
					SetTimer(hWnd, 1, 100, NULL);  
				}  
			}  
		}  
		break;  
		default:  
			return DefWindowProc(hWnd, message, wParam, lParam);  
		}  
	}  
	break;  
	case WM_TIMER:  
	{  
		if (nTimeEllapsed >= nTotalTime)  
		{  
			KillTimer(hWnd, 1);  
			Beep(6000, 500);  
			bShutDown = false;  
			//ExitWindowsEx(EWX_FORCE | EWX_SHUTDOWN, 0);  
			//ExitWindowsEx(EWX_FORCE | EWX_REBOOT, 0);  
		}  
		nTimeEllapsed += 100;  
		InvalidateRect(hWnd, NULL, TRUE);  
	}  
	break;  
	case WM_PAINT:  
	{  
		PAINTSTRUCT ps;  
		HDC hDC = BeginPaint(hWnd, &ps);  
		if (bShutDown)  
		{  
			RECT rc;  
			GetClientRect(hWnd, &rc);  
			WCHAR wsBuffer[255] = TEXT("");  
			float nSeconds = (nTotalTime - nTimeEllapsed) / 1000.0f;  
			swprintf(wsBuffer, L"Shutdown in : %.2f seconds\r\n", nSeconds);  
			int nFontSize = -MulDiv(32, GetDeviceCaps(hDC, LOGPIXELSY), 72);  
			HFONT hFont = CreateFont(nFontSize, 0, 0, 0, FW_DONTCARE, FALSE, FALSE, FALSE, ANSI_CHARSET, OUT_RASTER_PRECIS, CLIP_DEFAULT_PRECIS,  
				NONANTIALIASED_QUALITY, VARIABLE_PITCH | FF_DONTCARE, L"Arial");  
			HFONT hFontOld = (HFONT)SelectObject(hDC, hFont);  
			SetTextColor(hDC, RGB(255, 0, 0));  
			DrawText(hDC, wsBuffer, lstrlen(wsBuffer), &rc, DT_SINGLELINE | DT_CENTER | DT_VCENTER);  
			SelectObject(hDC, hFontOld);  
			DeleteObject(hFont);  
		}  
		EndPaint(hWnd, &ps);  
	}  
	break;  
	case WM_DESTROY:  
	{  
		PostQuitMessage(0);  
		return 0;  
	}  
	break;  
	default:  
		return DefWindowProc(hWnd, message, wParam, lParam);  
	}  
	return 0;  
}  

Answer 3

You can see MSDN doc at Shutting Down

Answer 4

The Shut down function is working but I see that in my code when i use ShutDown = TRUE , none of the previous lines are working. When Status message is true, i want the warning message to come and then after 3 sec the windows to shutdown. instead it goes straight to shutdown. Can you please suggest if it is because of sesystem privilage?

UINT Status;
bool ShutDown = FALSE;
INT_PTR CALLBACK DlgProc(HWND hDlg, UINT msg, WPARAM wP, LPARAM lP){

if (msg == Status){
........
// Warning message
Sleep (3000);
ShutDown = TRUE;
}
;:::::::::::::::::
::::::::::::::::::
if (ShutDown) {
 if (dwThisTID != dwCurrTID) 
 {
 AttachThreadInput(dwThisTID, dwCurrTID, TRUE);
 SystemParametersInfo(SPI_GETFOREGROUNDLOCKTIMEOUT, 0, &lockTimeOut, 0);
 SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, 0, SPIF_SENDWININICHANGE | SPIF_UPDATEINIFILE);
 AllowSetForegroundWindow(ASFW_ANY);
 }
 SetActiveWindow(hDlg);
 SetForegroundWindow(hDlg);
 SetFocus(hDlg);
 EnableWindow(hDlg, true);

 if (dwThisTID != dwCurrTID) {
 SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, (PVOID)lockTimeOut, SPIF_SENDWININICHANGE | SPIF_UPDATEINIFILE);
 AttachThreadInput(dwThisTID, dwCurrTID, FALSE);
 }


 SetWindowPos(hDlg, NULL, 0, 0, LOWORD(lP), HIWORD(lP), SWP_SHOWWINDOW);
 if (!OpenProcessToken(GetCurrentProcess(),
 TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken))
 return(FALSE);

 // Get the LUID for the shutdown privilege. 
 LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME, &tkp.Privileges[0].Luid);

 tkp.PrivilegeCount = 1; // one privilege to set    
 tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;

 // Get the shutdown privilege for this process. 
 AdjustTokenPrivileges(hToken, FALSE, &tkp, 0, (PTOKEN_PRIVILEGES)NULL, 0);

 ExitWindowsEx(EWX_FORCE | EWX_SHUTDOWN, 0);  //Windows herunterfahren
 //ExitWindowsEx(EWX_REBOOT, 0);
 ShutDown = FALSE;
 }
}

Answer 5

I realized it is much better to use shutdown in a callback function and call it with a timer.