在/home 下創建actor目錄，要求該目錄的擁有組爲actor，該組中成員在該目錄下有讀寫權限，組中成員在該目錄下創建的文件也屬於actor組

#cd /home
#mkdir actor
#ll
drwxr-xr-x   2 root   root    xxxxxxxxx actor
#chgrp actor actor
#ll
drwxr-xr-x   2 root   actor    xxxxxxxx actor
#chmod g=srwx actor
#ll
drwxrwsr-x   2 root    actor   xxxxxxxx actor

#cd actor
#su hooper
$touch h
$exit
#su romola
$touch r
$exit
#ll
-rw-rw-r--1 hooper actor 0 12 月 27 13:31 h
-rw-rw-r--1 romola actor 0 12 月 27 13:32 r