shell对比两个目录中有哪些文件不同

#!/bin/bash
read_dir(){
    for file in `ls -a $1`
    do
        if [ -d $1"/"$file ]
        then
            if [[ $file != ‘.‘ && $file != ‘..‘ ]]
            then
                read_dir $1"/"$file
            fi
        else

            diff $1"/"$file $(echo $1 | sed -e s‘/dir1/dir2/‘)"/"${file} 1>/dev/null 2>&1 && result=0 || result=1

            if [ "$result" == 1 ];then
                echo "$1"/"$file is diff" >> result.log
            fi
        fi
    done
}


read_dir /data/dir1