（2）Linux文件和目錄操做命令

簡單就是高效

pwd	cd -/~/..	tree–a/d/f/i/L	mkdir–p/v/m	touch
ls –l/a//i/h/F	cp –r/p/d/a	mv	rm –f/r/i	rmdir -pv 僅空
ln –s	readlink -f	find path –type/name/size 文件類型bcdplfs		xargs –dn
chgrp	umask	ch/lsattr-r+ai	file	md5sum
chown	chmod