How to receive OS notifications about windows shutdown/logoff

To create a process which must detect windows shutdown or log-off actions to perform necessary clean-up operations you can use many features.

One of them is to create Windows Service.
Another way is to subscribe to the system events notifications.

WinAPI provides a SetConsoleCtrlHandler function which able to add a callback for the calling process.

#include <windows.h>
HANDLE hEvent;
BOOL WINAPI ShutDownHandler(DWORD dwCtrlType)
{
    switch( dwCtrlType )
    {
        case CTRL_SHUTDOWN_EVENT:
        case CTRL_LOGOFF_EVENT: 
        case CTRL_CLOSE_EVENT: 
            SetEvent(hEvent);
            return TRUE;

        default:
            return FALSE;
    }
}
 
void main()
{
    hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
 
    SetConsoleCtrlHandler(ShutDownHandler, true);
 
    // your implementation
 
    WaitForSingleObject(hEvent,INFINITE); 
 
    // your clean-up
    CloseHandle (hEvent);
}