mkrootfs

#!/bin/bash

[ "$#" = "1" ] || { echo "Usage: $(basename "$0") filename_of_image"; exit 1; }

CWD=$(pwd)
BUSYBOX=busybox

TMPDIR=$(mktemp -d .tmp.XXXXXXXX)

cd $TMPDIR

mkdir -p dev etc/init.d mnt proc root sys tmp
chmod a+rwxt tmp

cp -rf ${CWD}/${BUSYBOX}/_install/* ./

mkdir -p usr/share/udhcpc
cp -rf ${CWD}/${BUSYBOX}/examples/udhcp/simple.script ./usr/share/udhcpc/default.script

cat << EOF > etc/profile
echo
echo "Let's hack the kernel!"
echo
EOF

cat << EOF > etc/fstab
proc  /proc  proc  defaults  0  0
sysfs  /sys  sysfs defaults  0  0
tmpfs  /tmp  tmpfs defaults  0  0
EOF

cat << EOF > etc/inittab
::sysinit:/etc/init.d/rcS
::respawn:-/bin/sh
tty2::askfirst:-/bin/sh
::ctrlaltdel:/bin/umount -a -r
EOF

cat << EOF > etc/init.d/rcS
#!bin/sh
/bin/mount -a
/sbin/mdev -s
/sbin/ifconfig eth0 up >/dev/null 2>&1 \
&& /sbin/udhcpc eth0 >/dev/null 2>&1
EOF

chmod 755 etc/init.d/rcS

find ./ | cpio -o -H newc | gzip > ${CWD}/${1}

cd $CWD

rm -rf $TMPDIR

exit 0