在不同的目录中查找文件并对文件名进行操作

$ ls /tmp/foo/
file1.txt  file2.txt
$ ls /tmp/bar/
file20.txt
$ ls /tmp/foo/file*.txt | grep -o -E '[0-9]+'  | sort -n | paste -s -d,
1,2
$ ls /tmp/foo/
file1.txt  file2.txt
$ ls /tmp/b