Getting the parent of a directory in Bash

Question

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

Works if there is a trailing slash, too.

Clearly the parent directory is given by simply appending the dot-dot filename:

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

But you must want the resolved path (an absolute path without any dot-dot path components):

/home/smith/Desktop             # resolved path

The problem with the top answers that use dirname, is that they don't work when you enter a path with dot-dots:

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

This is more powerful:

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

You can feed it /home/smith/Desktop/Test/.., but also more complex paths like:

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

NOTE: use of builtin ensures no user defined function variant of cd is called, but rather the default utility form which has no output.

Just use echo $(cd ../ && pwd) while working in the directory whose parent dir you want to find out. This chain also has the added benefit of not having trailing slashes.

...but what is "seen here" is broken. Here's the fix:

> pwd
/home/me
> x='Om Namah Shivaya'
> mkdir "$x" && cd "$x"
/home/me/Om Namah Shivaya
> parentdir="$(dirname "$(pwd)")"
> echo $parentdir
/home/me