Manual Installing busybox into android system

Copy busybox into filesystem
#./cp /sdcard/busybox /data/tmp
#./busybox ash

change system read/write
#mount -oremount,rw /dev/block/mmcblk0p2 /system

Enter /system/busybox and copy busybox into /system/busybox
#cd /system/busybox
#cp /data/tmp/busybox .

List all command of busybox
#./busybox > list
# vi list
# for I in `cat list `
> do
> ln bus> ln busybox $I
> done
/system/busybox # ls

Remove list file and change the mount from rw to ro
#rm list
#mount -oremount ,ro /dev/block/mmcblk0p2 /system

Then, you can list busybox command
#cd /system/busybox
#./ash
#export PATH='pwd':$PATH