Just look at the source code and you should be able to quickly figure out what this script does. It more or less turns your computer off and that's about it.

I highly recommend not installing this script. Below is a small sample of the script if you are too lazy to look at the code:

pw=`cat $tempfile`
Xdialog --title "Output" --screen-center --msgbox "OK, shutting down..." 10 40
expect -d - << EndMark
spawn "/bin/bash"
send "su\r"
expect -re "Password: "
sleep 1
send "$pw\r"
expect -re "#"
send "/sbin/halt\r"
expect -re "#"

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/sbin/halt\r
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this statement is a shutdown command