如何找到Bash中存在的最深的路径

Question

当我收到如下错误时：

$ ls /var/django-projects/daks/public/media/uploads/bandsaws/sneaks.jpg
ls: /var/django-projects/daks/public/media/uploads/bandsaws/sneaks.jpg: No such file or directory

我希望能够问what-is-the-deepest-path-that-does-exists然后回来，说：

/var/django-projects/daks/public/media/

我认为可以通过在每次迭代中添加../的循环来完成，并在找到存在的路径时退出。

Answer 1

您可能会发现dirname有用。例如：

f=/var/django-projects/daks/public/media/uploads/bandsaws/sneaks.jpg

until [ -e "$f" ]; do f=$(dirname "$f"); done

echo $f

应该给你/var/django-projects/daks/public/media/

Answer 2

尝试：

FILE="/var/django-projects/daks/public/media/uploads/bandsaws/sneaks.jpg"
while true; do [ -e "$FILE" ] && break || FILE=$(dirname "$FILE"); done; echo $FILE

Answer 3

#!/bin/bash
function firstValidParent () { 
    d="$1"
    [ -e "${d}" ] && echo $d || firstValidParent "${d%/*}"
}