这个会被放到父文件夹中

cd ../

如果你只需要父目录的名称:

parent_dir_name=$(basename $(dirname $PWD))

丑陋但高效

function Parentdir()

{

local lookFor_ parent_ switch_ i_

lookFor_="$1"

#if it is not a file, we need the grand parent
[ -f "$lookFor_" ] || switch_="/.."

#length of search string
i_="${#lookFor_}"

#remove string one by one until it make sens for the system
while [ "$i_" -ge 0 ] && [ ! -d "${lookFor_:0:$i_}" ];
do
    let i_--
done

#get real path
parent_="$(realpath "${lookFor_:0:$i_}$switch_")" 

#done
echo "
lookFor_: $1
{lookFor_:0:$i_}: ${lookFor_:0:$i_}
realpath {lookFor_:0:$i_}: $(realpath ${lookFor_:0:$i_})
parent_: $parent_ 
"

}

    lookFor_: /home/Om Namah Shivaya
{lookFor_:0:6}: /home/
realpath {lookFor_:0:6}: /home
parent_: /home 


lookFor_: /var/log
{lookFor_:0:8}: /var/log
realpath {lookFor_:0:8}: /UNIONFS/var/log
parent_: /UNIONFS/var 


lookFor_: /var/log/
{lookFor_:0:9}: /var/log/
realpath {lookFor_:0:9}: /UNIONFS/var/log
parent_: /UNIONFS/var 


lookFor_: /tmp//res.log/..
{lookFor_:0:6}: /tmp//
realpath {lookFor_:0:6}: /tmp
parent_: / 


lookFor_: /media/sdc8/../sdc8/Debian_Master//a
{lookFor_:0:35}: /media/sdc8/../sdc8/Debian_Master//
realpath {lookFor_:0:35}: /media/sdc8/Debian_Master
parent_: /media/sdc8 


lookFor_: /media/sdc8//Debian_Master/../Debian_Master/a
{lookFor_:0:44}: /media/sdc8//Debian_Master/../Debian_Master/
realpath {lookFor_:0:44}: /media/sdc8/Debian_Master
parent_: /media/sdc8 


lookFor_: /media/sdc8/Debian_Master/../Debian_Master/For_Debian
{lookFor_:0:53}: /media/sdc8/Debian_Master/../Debian_Master/For_Debian
realpath {lookFor_:0:53}: /media/sdc8/Debian_Master/For_Debian
parent_: /media/sdc8/Debian_Master 


lookFor_: /tmp/../res.log
{lookFor_:0:8}: /tmp/../
realpath {lookFor_:0:8}: /
parent_: /

dir=/home/smith/Desktop/Test
parentdir="$(dirname "$dir")"

如果后面有斜杠，也可以。

根据你是否需要绝对路径，你可能需要额外的步骤:

child='/home/smith/Desktop/Test/'
parent=$(dirname "$child")
abs_parent=$(realpath "$parent")

显然，父目录是通过简单地附加点。点文件名来给出的:

/home/smith/Desktop/Test/..     # unresolved path

但你必须要解析路径(没有任何点-点路径组件的绝对路径):

/home/smith/Desktop             # resolved path

使用dirname的顶部答案的问题是，当你输入一个带有点号的路径时，它们不起作用:

$ dir=~/Library/../Desktop/../..
$ parentdir="$(dirname "$dir")"
$ echo $parentdir
/Users/username/Library/../Desktop/..   # not fully resolved

这个更强大:

dir=/home/smith/Desktop/Test
parentdir=$(builtin cd $dir; pwd)

你可以在/home/smith/Desktop/Test/..，但也有更复杂的路径，比如:

$ dir=~/Library/../Desktop/../..
$ parentdir=$(builtin cd $dir; pwd)
$ echo $parentdir
/Users                                  # the fully resolved path!
 

注意:使用内置确保不会调用用户定义的cd函数变体，而是调用没有输出的默认实用程序形式。