Renaming multiple different file extensions with BASH script

Question

I'm trying to create a bash script that takes a directory full of files (about 500 files) that have all different types of extensions (no seriously, like 30 different types of extensions) and I want get rid of all of the extensions, and replace them with .txt

I've been searching around for a while now, and can only find examples of taking a specified extension, and changing it to another specified extension. Like png --> jpg, or .doc --> .txt

Here's an example I've found:

# Rename all *.txt to *.text
for f in *.txt; do 
mv -- "$f" "${f%.txt}.text"
done

This works, but only if you go from .txt to .text, I have multiple different extensions I'm working with.

My current code is:

directory=$1
for item in $directory/*
do
echo mv -- "$item" "$item.txt";
done

This will append the .txt onto them, but unfortunately I am left with the previous ones still attached. E.G. filename.etc.txt, filename.bla.txt

Am I going about this wrong? Any help is greatly appreciated.

Why not using regex?

bigbounty
– bigbounty

2017-09-19 05:27:14 +00:00
Commented Sep 19, 2017 at 5:27 — bigbounty
– bigbounty, Commented Sep 19, 2017 at 5:27
my knowledge of regex is very limited, could you elaborate?

Brandon
– Brandon

2017-09-19 05:44:03 +00:00
Commented Sep 19, 2017 at 5:44 — Brandon
– Brandon, Commented Sep 19, 2017 at 5:44

o11c · Accepted Answer · 2017-09-19 05:48:52Z

1

It's a trivial change to the first example:

cd "$directory"
# Rename all files to *.txt
for f in *
do 
    mv -- "$f" "${f%.*}.txt"
done

If a file contains multiple extensions, this will replace only the last one. To remove all extensions, use %% in place of %.

answered Sep 19, 2017 at 5:48

o11c

16.5k5 gold badges57 silver badges80 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Brandon Over a year ago

Thanks! That worked great, but I'm not understanding whats happening inside the move function, what does the %.* do to change the situation?

o11c Over a year ago

Read the "Pattern Matching" section of the bash(1) man page or documentation.

Collectives™ on Stack Overflow

Renaming multiple different file extensions with BASH script

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related