[BoRoV]

Вот для CMD:

Код:

var
  hWnd: THandle;
  cmd: string;
  i: integer;
begin
  hWnd := FindWindow('ConsoleWindowClass', nil);
  cmd := 'ping ya.ru' + #13;
  if hWnd <> 0 then
    for i := 1 to Length(cmd) do
      SendMessage(hWnd, WM_CHAR, Ord(cmd[i]), 0);
  ExitProcess(0);
end;