检测磁盘空间，删除指定类型最早创建的文件

#!/bin/bash
while [ 1 ]
do
sleep 30
avail=`df / -h | awk '{print $4}' | awk '{sum+=$1}END{print sum}'`
echo "disk avail:"$avail"G"
if [ $avail -lt 5 ]
then
echo "disk avail:"$avail"G is less than 5G ,will rm one mp4"
for file in `ls -lrt $1/*/*mp4`
do
if [ "${file##*.}" != mp4 ]
then
continue
fi
echo "rm "$file
rm $file -rf
break
done
fi
done