#!/bin/bash
#create_grub_cd
#Run as root in root's home directory

#Create an enpty file floppy sized
dd if=/dev/zero of=fd_file bs=512 count=2880
#Write an MSDOS file system to the file
mkfs -t msdos fd_file

#Check for a mount point
if ([ ! -d /mnt/zip ]);then mkdir /mnt/zip;fi

#Mount the file as a loopback devive (/dev/loop0 by default)
mount -o loop fd_file /mnt/zip

#Create the directory structure for grub
mkdir /mnt/zip/boot
mkdir /mnt/zip/boot/grub
#Copy the essential grub files
cp /usr/share/grub/i386-redhat/* /mnt/zip/boot/grub

#Create a prototype grub.conf file
#Uncomment and modify if require
#The cd will boot to a grub> prompt if left commented out
#cat > /mnt/zip/boot/grub/grub.conf<<END_OF_CONF
#timeout=10
#default=0
#
#title FC4T2 i386 USB
#	kernel (hd0,0)/vmlinuz-2.6.11-1.1226_FC4 ro root=/dev/sda2
#	initrd (hd0,0)/initrd_usb.gz
#
#title Windows
#	rootnoverify (hdx,y)
#	chainloader +1
#END_OF_CONF

#Check if /dev/fd0 exists, mv it if it does
if ([ -e /dev/fd0 ]);then mv /dev/fd0 /dev/fd0_orig;fi

#Link /dev/fd0 to /dev/loop1 to fool grub !!
ln -s /dev/loop0 /dev/fd0

#Run grub in batch mode
/sbin/grub --batch <<EOF
root (fd0)
setup (fd0)
quit
EOF

#restore fd0 if required
rm -f /dev/fd0
if([ -e /dev/fd0_orig ]);then mv /dev/fd0_orig /dev/fd0;fi

umount /mnt/zip
######################################################
#Now make a bootable CD ISO image
# Make a dummy directory in /tmp
mkdir /tmp/dummy
#Copy the floppy image file to /tmp/dummy
cp fd_file /tmp/dummy
# Create the ISO image grub_image.iso
mkisofs -b fd_file -o /tmp/grub_image.iso /tmp/dummy
rm -rf /tmp/dummy
######################################################
#Modify the following commands as required
#Possibly the ATA: will not be required
#cdrecord -scanbus
#cdrecord dev=ATA:1,0,0 speed=8 /tmp/grub_image.iso
######################################################