How to SET a variable to the path of parent directory on windows?

Question

Struggling with command line again, I have figure out that I can store the current working directory in a variable like so:

SET current=%cd%

How would I set parent though? SET parent=%..% does not work, as it echoes %..%

Basically, calling a batch script C:\a\b\myscript.bat with the following contents:

@echo off
set current=%cd%
echo %current%

prints C:\a\b and I should like to set a variable parent so that it would print C:\a without changing the current working directory to ..

Is this possible?

Answer 1

Move up a directory, remembering the current, set the parent, and then pop down a directory, back to where you started

@echo off
set current=%cd%
pushd ..
set parent=%cd%
popd

echo current %current%
echo parent %parent%

Answer 2

You could also do something like this:

set current=%CD%
set parent=%CD%\..

It doesn't give you the canonical name of the parent, but it should always be a valid path to the parent folder. It will also be somewhat faster than the solutions involving pushd and popd, but that won't be the primary consideration in a batch file.

Edit: Note that all of the solutions so far, including mine here, will have problems if the current folder is the root of a drive. There is no clean and easy way out of that one, since there really is no parent of a drive visible to user mode.