some console commands without console makes gui programs killed

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https://bbs.archlinux.org – I'm using openbox as WM. I think it is openbox that causes the troubleit seems that when I try ot execute some console application without console but the application needs user input, the problem occurs.when the issue arises, gui programs gets killed, leaving its window blank.not all of gui programs though, chromium and conky got closed but xterm didn't.however, they survive when they are executed with xterm.I could reproduce the problem with sudo or alsamixer, run by either right-click menu or gmrun.Is there anyone experiencing the same issue?sorry for my english. freaxtux (HowTos)