1 #!/bin/sh 2  3 export DS_DIR=/home/cxy/test 4  5 if [ ! -d $DS_DIR ]; then 6     mkdir $DS_DIR 7 else 8     echo "$DS_DIR is not existed!" 9 fi10 11 cd $DS_DIR12 if [ $(ls -l | grep "install-*" | wc -l) > 3 ]; then13     echo "more than 2 dst_files in $DS_DIR"14     rm -r $(ls -rt | head -n2)15 fi