linux中数组、计算、获取文件类型

1、获取文件类型

[root@localhost ~]# filename="/root/data/aa.gz"
[root@localhost ~]# echo ${filename##*.}
gz
[root@localhost ~]# filename="/root/data/aa.dat"
[root@localhost ~]# echo ${filename##*.}
dat
[root@localhost ~]# var=/dir1/dir2/file.txt
[root@localhost ~]# echo ${var##*/}
file.txt
[root@localhost ~]# echo ${var##*.}
txt
[root@localhost ~]# echo ${var%/*}
/dir1/dir2
[root@localhost ~]# echo ${var%.*}
/dir1/dir2/file

 参考：https://www.cnblogs.com/nzbbody/p/4391802.html