实例：实现自动清除日期目录shell脚本

[root@SZDB ~]# more purge_datedir.sh  

#!/bin/bash 

# Author: Leshami 

# Blog : http://blog.csdn.net/leshami 

RemoveDir=/log/hotbak/physical 

dt=`date+%Y%m%d-d"3 day ago"` 

forsubdirin`ls $RemoveDir`; 

do 

  if["${subdir}"\<"${dt}"]; 

    then  

    rm-rf $RemoveDir/$subdir >/dev/null 

    echo"The directory $RemoveDir/$subdir has been removed." 

  fi 

done

[root@SZDB ~]# ls /log/hotbak/physical 

2014120320141210201412172014122420141231201501072015011420150125tmp.sh 

2014120720141214201412212014122820150104201501112015012120150128 

[root@SZDB ~]# ./purge_datedir.sh  

The directory/log/hotbak/physical/20141203has been removed. 

The directory/log/hotbak/physical/20141207has been removed. 

The directory/log/hotbak/physical/20141210has been removed. 

The directory/log/hotbak/physical/20141214has been removed. 

The directory/log/hotbak/physical/20141217has been removed. 

The directory/log/hotbak/physical/20141221has been removed. 

The directory/log/hotbak/physical/20141224has been removed. 

The directory/log/hotbak/physical/20141228has been removed. 

The directory/log/hotbak/physical/20141231has been removed. 

The directory/log/hotbak/physical/20150104has been removed. 

The directory/log/hotbak/physical/20150107has been removed. 

The directory/log/hotbak/physical/20150111has been removed. 

The directory/log/hotbak/physical/20150114has been removed. 

The directory/log/hotbak/physical/20150121has been removed. 

[root@SZDB ~]# ls /log/hotbak/physical 

2015012520150128