Dear PHP support, I have a question on an exec() command, if I would like to switch user right on Unix server, what command should I use? example: on the UNIX shell will be like below $su root Password:'password' but when I tried running exec() command on PHP, I couldn't do that exec("su root"); I can't sent a password thru the exec() command, any way to do that? Thank you very much Sitthipong Thuetham sitthbkk@xxxxxxx<mailto:sitthbkk@xxxxxxx>