Something
public text v1 · immutable#! /bin/sh
diskname=`basename "$3"`
rdisk=`df | grep "$diskname" | awk '{print $1}'`
echo $rdisk
umount -f "$rdisk"
dd if=/usr/standalone/i386/boot1h of=$rdisk bs=512 count=1
/usr/sbin/startupfiletool $rdisk /usr/standalone/i386/boot
mount -t hfs "$rdisk" "$3"
echo "startupfile done !"
sleep 20
exit 0