Fun with scripting shells (how to rename multiple files in PowerShell).

I stumbled across this post by Rob Newcater on RootPrompt.org which points to this post on BasicallyTech.com. It shows the various ways that you can rename or manipulate filenames in groups using the bash shell and a smattering of standard UNIX utilities.

The sample given was renaming a directory full of *.mp3 files such that all the spaces were replaced with underscores – here is the script in BASH:

for FILE in *.mp3 ; do NEWFILE=`echo $FILE | sed ’s/ /_/g’` ; echo “$FILE will be renamed as $NEWFILE” ; done

That is pretty cool, although it is much more concise in PowerShell:

get-childitem *.mp3 | foreach { rename-item $_ $_.Name.Replace(” “, “_”) }

And by concise, I don’t mean shorter. One of the advantages of PowerShell over traditional text-piping shells is that you are dealing with objects which provide a lot more data to the next part of the processing pipeline. If you are into punctuation you could express it as:

gci *.mp3 | % { rename-item $_ $_.Name.Replace(” “, “_”) }

But to be honest, I prefer it the first way.