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"`

for subdir in `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
20141203  20141210  20141217  20141224  20141231  20150107  20150114  20150125  tmp.sh
20141207  20141214  20141221  20141228  20150104  20150111  20150121  20150128

[root@SZDB ~]# ./purge_datedir.sh 
The directory /log/hotbak/physical/20141203 has been removed.
The directory /log/hotbak/physical/20141207 has been removed.
The directory /log/hotbak/physical/20141210 has been removed.
The directory /log/hotbak/physical/20141214 has been removed.
The directory /log/hotbak/physical/20141217 has been removed.
The directory /log/hotbak/physical/20141221 has been removed.
The directory /log/hotbak/physical/20141224 has been removed.
The directory /log/hotbak/physical/20141228 has been removed.
The directory /log/hotbak/physical/20141231 has been removed.
The directory /log/hotbak/physical/20150104 has been removed.
The directory /log/hotbak/physical/20150107 has been removed.
The directory /log/hotbak/physical/20150111 has been removed.
The directory /log/hotbak/physical/20150114 has been removed.
The directory /log/hotbak/physical/20150121 has been removed.

[root@SZDB ~]# ls /log/hotbak/physical
20150125  20150128