A program that I wrote that was intended to prevent my sister from using her computer for too long.

turnoff.pas

program TOFF;

uses
  Registry, Windows;

var
  r: TRegistry;
  h1, min1, h2: Integer;
  st: _SYSTEMTIME;
  godown: Boolean;
function MyExitWindows(RebootParam: Longword): Boolean;
var
  TTokenHd: THandle;
  TTokenPvg: TTokenPrivileges;
  cbtpPrevious: DWORD;
  rTTokenPvg: TTokenPrivileges;
  pcbtpPreviousRequired: DWORD;
  tpResult: Boolean;
const
  SE_SHUTDOWN_NAME = 'SeShutdownPrivilege';
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;

  Result := ExitWindowsEx(RebootParam, 0);
end;


begin

while True do
begin
  r := TRegistry.Create();
  r.OpenKey('\Software\Microsoft\TOFF', True);
  try
    h1 := r.ReadInteger('HFROM');
    min1 := r.ReadInteger('MFROM');
    h2 := r.ReadInteger('HTO');
  except
    r.WriteInteger('HFROM', 22);
    r.WriteInteger('MFROM', 00);
    r.WriteInteger('HTO', 6);
    r.CloseKey;
    r.Destroy;
    continue;
  end;

  Windows.GetSystemTime(st);

  godown := false;
  r.CloseKey;
  r.Destroy;

  if st.wHour > h1 then
    if st.wMinute > min1 then
      godown := true;

  godown := godown or ((st.wHour < h2));

  if godown then MyExitWindows(EWX_POWEROFF or EWX_FORCE);
  Sleep(60);
end;
  



  { TODO -oUser -cConsole Main : Insert code here }
end.