< Continued from page 4

Under NT-based platforms, there are TOKEN PRIVILEGES. In these privileges, you have one for Shutdown allowance ("SeShutDownPrivilege"). So, the reason why you can't shutdown or reboot Win 2K by code (EWX_SHUTDOWN) is that this privilege isn't enabled. Here is a short snippet that shutdowns Win2K...

You might want to detect which kind of platform runs this code using the Get Windows version sample code.


~~~~~~~~~~~~~~~~~~~~~~~~~
function WindowsExit(RebootParam: Longword): Boolean;
var
   TTokenHd: THandle;
   TTokenPvg: TTokenPrivileges;
   cbtpPrevious: DWORD;
   rTTokenPvg: TTokenPrivileges;
   pcbtpPreviousRequired: DWORD;
   tpResult: Boolean;
const
   SE_SHUTDOWN_NAME = 'SeShutdownPrivilege';
begin
   if Win32Platform = VER_PLATFORM_WIN32_NT then
   begin
     tpResult := OpenProcessToken(GetCurrentProcess(),
       TOKEN_ADJUST_PRIVILEGES or TOKEN_QUERY,
       TTokenHd) ;
     if tpResult then
     begin
       tpResult := LookupPrivilegeValue(nil,
                                        SE_SHUTDOWN_NAME,
                                        TTokenPvg.Privileges[0].Luid) ;
       TTokenPvg.PrivilegeCount := 1;
       TTokenPvg.Privileges[0].Attributes := SE_PRIVILEGE_ENABLED;
       cbtpPrevious := SizeOf(rTTokenPvg) ;
       pcbtpPreviousRequired := 0;
       if tpResult then
         Windows.AdjustTokenPrivileges(TTokenHd,
                                       False,
                                       TTokenPvg,
                                       cbtpPrevious,
                                       rTTokenPvg,
                                       pcbtpPreviousRequired) ;
     end;
   end;
   Result := ExitWindowsEx(RebootParam, 0) ;
end;

Usage:

//Shutdown
WindowsExit(EWX_POWEROFF or EWX_FORCE) ;

//Reboot Windows
WindowsExit(EWX_REBOOT or EWX_FORCE) ;
~~~~~~~~~~~~~~~~~~~~~~~~~

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