Simple init process to start basic services and get a root shell with job control

init.shell

#!/bin/sh
#
# Simple /sbin/init replacement that runs all runlevel S scripts, then drops
# into a root shell, in an infinite loop.
#
# Using this script as "init=" is similar to using the "single" boot parameter,
# but doesn't require a password, and logging out won't resume booting.  And
# unlike "init=/bin/sh", this provides job control and runs the basic scripts.

/etc/init.d/rc S

while true; do
	setsid sh -c 'exec login -f root </dev/tty1 >/dev/tty1 2>&1'
done