为啥ls -d */列出所有目录

ls -F会在目录名后面加/:

　　-F, --classify[=WHEN] append indicator (one of */=>@|) to entries WHEN

但ls -d */是因为bash的expansion. 我们可以写个 ls.sh，其 echo $* 来证实这一点。

我们还可以如下，sadly我解释不动了：

$ ls -F
dir-a/  dir-b/  file-c

$ t=*/; echo $t
dir-a/ dir-b/

$ t='*/'; echo $t
dir-a/ dir-b/

$ t="*/"; echo $t
dir-a/ dir-b/

$ echo */
dir-a/ dir-b/

$ echo '*/'
*/

$ echo "*/"
*/

https://www.gnu.org/software/bash/manual/html_node/Shell-Expansions.html

The order of expansions is:

• brace expansion;
• tilde (~) expansion,
• parameter and variable expansion,
• arithmetic expansion,
• and command substitution (done in a left-to-right fashion);
• word splitting;
• filename expansion;
• and quote removal.