terminal - AppleScript close window on 'do shell hdiutil stdinpass' timeout -

running 'do shell hdiutil create -encryption -stdinpass' pops "enter disk image passphrase:" request expected. if no entry made i'd timeout , close window.

the close command pops 'do want close window?' dialog, warning running process hdiutil terminated.

how should terminate hdiutil close window command can close window no running hdiutil processes? don't want terminate hdiutil processes, 1 associated particular 'do shell'.

alternatively, how unconditionally close window, running processes or not?