An implementation of 'du -s *' in Powershell

While reading about Powershell I noticed that there's no out-of-the-box way(that I know of) to do something similar to 'du -s *' in Unix/Linux. In this post I'm going to show how to implement a similar functionality.

The -s option of the du is used to show only a the total size each argument. This is very useful when trying to determine which directories or files are taking too much space. For example:

$ cd /cygdrive/c/Python25/
$ du -bs *
4794012 DLLs
4160038 Doc
13817   LICENSE.txt
13752327        Lib
88573   NEWS.txt
56691   README.txt
547784  Tools
382592  include
948600  libs
24064   python.exe
24576   pythonw.exe
3248808 tcl
4608    w9xpopen.exe

For better results the output could be combined with sort.

$ du -bs * | sort -n
4608    w9xpopen.exe
13817   LICENSE.txt
24064   python.exe
24576   pythonw.exe
56691   README.txt
88573   NEWS.txt
382592  include
547784  Tools
948600  libs
3248808 tcl
4160038 Doc
4794012 DLLs
13752327        Lib

In order to implement this in Powershell (with the little knowledge I have from it) I wanted to implement the following strategy

1. get all the child elements from the base directory


2. for each element get the total size


3. generate a tuple with the element name and the total size

In order to implement #1 a common get-childitem command was used. To implement #2, a combination of foreach-object + get-childitem -r + measure-object was used. And finally for #3 the select-object command was used.

One implementation for this functionality is the following:

function directory-summary($dir=".") { 
  get-childitem $dir | 
    % { $f = $_ ; 
        get-childitem -r $_.FullName | 
           measure-object -property length -sum | 
             select @{Name="Name";Expression={$f}},Sum}
}

Running this command in the same directory shows:

PS C:\Python25> directory-summary

Name                  Sum
----                  ---
DLLs              4794012
Doc               4160038
include            382592
Lib              13752327
libs               948600
tcl               3248808
Tools              547784
LICENSE.txt         13817
NEWS.txt            88573
python.exe          24064
pythonw.exe         24576
README.txt          56691
w9xpopen.exe         4608

We can also sort the results:

PS C:\Python25> directory-summary | sort sum

Name                  Sum
----                  ---
w9xpopen.exe         4608
LICENSE.txt         13817
python.exe          24064
pythonw.exe         24576
README.txt          56691
NEWS.txt            88573
include            382592
Tools              547784
libs               948600
tcl               3248808
Doc               4160038
DLLs              4794012
Lib              13752327

Maybe there's a shorter/better way to implement this, however it was very interesting and fun to learn a little bit more about Powershell while trying to solve this.