shell脚本判断硬盘使用状况并自动发邮件

#!/bin/bash

HD_MAX=`df -h | grep sda3 | awk '{print $5}'`

#if [ $HD_MAX -gt 50% ];then

df -h | grep sda3 > ~/mail.txt

if [ `echo $HD_MAX | awk -v bi=50% '{print($1>bi)?"1":"0"}'` -eq "1" ];then

        /bin/mail -s "hard disk is warning" ***********@hotmail.com < ~/mail.txt

echo $HD_MAX

#echo $DISk

fi