问Inno Setup Exec()函数等待有限的时间

EN

[Code]
#IFDEF UNICODE
  #DEFINE AW "W"
#ELSE
  #DEFINE AW "A"
#ENDIF

const
  WAIT_TIMEOUT = $00000102;
  SEE_MASK_NOCLOSEPROCESS = $00000040;

type
  TShellExecuteInfo = record
    cbSize: DWORD;
    fMask: Cardinal;
    Wnd: HWND;
    lpVerb: string;
    lpFile: string;
    lpParameters: string;
    lpDirectory: string;
    nShow: Integer;
    hInstApp: THandle;    
    lpIDList: DWORD;
    lpClass: string;
    hkeyClass: THandle;
    dwHotKey: DWORD;
    hMonitor: THandle;
    hProcess: THandle;
  end;

function ShellExecuteEx(var lpExecInfo: TShellExecuteInfo): BOOL; 
  external 'ShellExecuteEx{#AW}@shell32.dll stdcall';
function WaitForSingleObject(hHandle: THandle; dwMilliseconds: DWORD): DWORD; 
  external 'WaitForSingleObject@kernel32.dll stdcall';
function TerminateProcess(hProcess: THandle; uExitCode: UINT): BOOL;
  external 'TerminateProcess@kernel32.dll stdcall';

function NextButtonClick(CurPageID: Integer): Boolean;
var
  ExecInfo: TShellExecuteInfo;
begin
  Result := True;

  if CurPageID = wpWelcome then
  begin
    ExecInfo.cbSize := SizeOf(ExecInfo);
    ExecInfo.fMask := SEE_MASK_NOCLOSEPROCESS;
    ExecInfo.Wnd := 0;
    ExecInfo.lpFile := 'calc.exe';
    ExecInfo.nShow := SW_HIDE;

    if ShellExecuteEx(ExecInfo) then
    begin
      if WaitForSingleObject(ExecInfo.hProcess, 3000) = WAIT_TIMEOUT then
      begin
        TerminateProcess(ExecInfo.hProcess, 666);
        MsgBox('You just killed a little kitty!', mbError, MB_OK);
      end
      else
        MsgBox('The process was terminated in time!', mbInformation, MB_OK);
    end;
  end;
end;