转载自:https://www.cnblogs.com/nzbbody/p/4391802.html
\({}用于字符串的读取,提取和替换功能,可以使用\){} 提取字符串
[root@localhost log]# var=/dir1/dir2/file.txt
[root@localhost log]# echo ${var##*/}
file.txt
[root@localhost log]# echo ${var##*.}
txt
[root@localhost log]# tmp=${var##*/}
[root@localhost log]# echo $tmp
file.txt
[root@localhost log]# echo ${tmp%.*}
file
[root@localhost log]# echo ${var%/*}
/dir1/dir2
使用文件目录的专有命令basename和dirname
[root@localhost log]# echo $(basename $var)
file.txt
[root@localhost log]# echo $(basename $var .txt)
file
[root@localhost log]# dirname $var
/dir1/dir2
[root@localhost log]# echo $(dirname $var)
/dir1/dir2
原文:https://www.cnblogs.com/xujingrong/p/9473496.html