Command to show how much free space left in current filesystem

echo "Percentage free space:"; echo; for DEV in `df | egrep '^/dev' | awk '{print $1}'`; \
do echo -n "$DEV =>  "; echo `dumpe2fs -h $DEV 2>/dev/null | grep 'lock count' | tr -t '\n' ' ' | \
        awk '{printf "100*%s/%s", $3-$7, $3, "free"}'` | bc; done