1. 根目录:
2. tools
3. testing
4. selftests
5. lib
6. printf.sh

#!/bin/sh
# Runs printf infrastructure using test_printf kernel module

if /sbin/modprobe -q test_printf; then
	/sbin/modprobe -q -r test_printf
	echo "printf: ok"
else
	echo "printf: [FAIL]"
	exit 1
fi