How Ubuntu turns off Grub Interactive editing

How does Ubuntu turn off Grub Interactive editing?

Grub

Grub> Md5crypt

Password: Hu Jintao (Ubuntu)

Encrypted: $1$zwnke0$1fzdbvjuct1mpdd4u/t961 (Encrypted password)

Grub> quit

sudo cp/boot/grub/menu.lst/boot/grub/menu.lst_backup

sudo gedit/boot/grub/menu.lst

Search this passage

...

# If used in the ' A ' menu file, disable all interactive editing

# Control (menu entry editor and command-line) and entries protected by the

# command ' Lock '

# For example Password Topsecret

# password--md5 $1$glhu0/$aW 78khk1qfv3p2b2znuoe/

# password Topsecret

...

Add the following line below

Password--md5 $1$zwnke0$1fzdbvjuct1mpdd4u/t961 (this is a coded password)

Search this passage

...

Title http://www.aliyun.com/zixun/aggregation/13835.html ">ubuntu, kernel 2.6.10-5-386 (recovery mode)

Root (hd0,1)

kernel/boot/vmlinuz-2.6.10-5-386 root=/dev/hda2 RO Single

Initrd/boot/initrd.img-2.6.10-5-386

Savedefault

Boot

...

Replace it with the following lines

#title Ubuntu, kernel 2.6.10-5-386 (recovery mode)

#root (hd0,1)

#kernel/boot/vmlinuz-2.6.10-5-386 root=/dev/hda2 Ro single

#initrd/boot/initrd.img-2.6.10-5-386

#savedefault

#boot

Save the edited file.