GRUB2 requires "press any key to continue" for failed HD search

[kernal42]

I have a GRUB2 menu item which looks for a particular hard drive by UUID. If the drive is present, GRUB2 boots into one operating system (Windows). If the drive is not present, GRUB2 boots into another instead (Ubuntu). I check to see if the drive is attached with "search --fs-uuid --no-floppy --set=foo $foo_uuid". This all works correctly.

The problem I encounter is that if search is unable to find the drive in question, it requires me to press a key to continue. This is not a desired effect - I make this check specifically so I will not have to provide further input.

Is there a way to bypass the "press any key to continue..." statement? Is there a different way to determine the presence of the drive that will not require keyboard input upon failure?

My goal here is to have a hardware switch to designate the OS to boot into so I don't accidentally miss the GRUB menu and therefore need to reboot. The switch connects or disconnects a flash drive from the computer. The hardware switch works; the script mostly works; the only hangup is the requirement to press a key to continue the boot.

My 40_custom file:


menuentry "auto" {
set foo_uuid=2CAD-0AA8
set foo=empty

insmod part_gpt
# insmod vfat
insmod search_fs_uuid

search --fs-uuid --no-floppy --set=foo $foo_uuid

if [ $foo = "empty" ]; then
#boot linux
recordfail
gfxmode $linux_gfx_mode
insmod gzio
insmod part_msdos
insmod ext2
set root='(hd3,msdos4)'
search --no-floppy --fs-uuid --set=root bc1ba5fa-971c-4a94-b808-0b28855647af
linux /boot/vmlinuz-3.2.0-26-generic root=UUID=bc1ba5fa-971c-4a94-b808-0b28855647af ro quiet splash $vt_handoff
initrd /boot/initrd.img-3.2.0-26-generic
else
#boot windows
insmod part_msdos
insmod ntfs
set root='(hd3,msdos1)'
search --no-floppy --fs-uuid --set=root CA3C07483C072F4F
chainloader +1

fi
}

Thanks,
Kernal