chroot into a rootfs for the same architecture

do_chroot

#!/bin/sh
#
# chroot into a rootfs for the same architecture
# usage: sudo ./do_chroot rootdir

echo chrooting into $1
mkdir -p $1/proc
mkdir -p $1/sys
mkdir -p $1/dev

cp /etc/resolv.conf $1/etc

mount --bind /proc $1/proc
mount --bind /sys $1/sys
mount --bind /dev $1/dev
mount --bind /dev/pts $1/dev/pts

chroot $1 /bin/bash

umount $1/dev/pts
umount $1/dev
umount $1/sys
umount $1/proc || umount -lf $1/proc

rm $1/etc/resolv.conf
rm $1/var/lib/dbus/machine-id