If you're using the terminal emulator app on your phone you need to start directly from su command.
i have a noobish question here, as you said above, you can use terminal emulator. so it is safe to flash clockworkmod recovery without using adb on pc but just with terminal emulator on phone? i apologize if im not making sense. my phone is a samsung galaxy ace, im doing this on my wife's phone an LG optimus net p690. please reply if you have time. thank you..
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